THE FRESHWATER CRAYFISH AUSTROPOTAMOBIUS PALLIPESIN SOUTH TYROL: HERITAGE SPECIES AND BIOINDICATOR

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FÜREDER L.

2003-04-01

Full Text Available Rapid decline of crayfish in European freshwaters and continuing threat necessitate integrated actions in conservation and management of native crayfish populations. Besides biological reasons (diseases, plague, the impact of toxic and harmful substances (fertilisers, herbicides or wastewater effluents, habitat alteration or fragmentation have been responsible for their decline in some regions. The same is true for the region of South Tyrol, where compared to previous investigations, only 10 of a former total of 15 crayfish locations in the water bodies could be affirmed. Although two new populations of the non-indigenous Astacus astacus were detected, the native Austropotamobius pallipes continues to decline. While many investigations have focused accurately on causal coherences for the decline of native populations, the properties of crayfish facilitate to reverse the situation. In a few examples, the potential of Austropotamobius pallipes, the native crayfish in South Tyrol, as “surrogate species” for effective biological conservation is discussed. Given the various adequate attributes of freshwater crayfish as surrogate species (including indicator species, umbrella species and flagship species qualities, they may help to advance not only the crayfish situation itself but also freshwater ecosystem properties in general.

Continental-wide distribution of crayfish species in Europe: update and maps

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Kouba A.

2014-01-01

Full Text Available Recently published astacological studies substantially improved available data on distribution of crayfish in various European regions. At the same time, spread of invasive species has been recorded, additional non-indigenous species became established in various countries, and losses of populations of native species due to crayfish plague and other negative factors were observed. We overview recent advances in this knowledge, and provide updated colour maps of the distribution of all crayfish species present in Europe. These maps are originally based on the data from the Atlas of Crayfish in Europe published in 2006 as a result of the CRAYNET project, and were further updated from more recently published reports, grey literature, and especially thanks to contributions and feedback of over 70 specialists from 32 countries. Separate maps are available for all indigenous crayfish species in Europe as well as for three most widespread non-indigenous crayfish species. Additionally, two maps give locations of known findings of crayfish species introduced to Europe after 1980. These newly established alien species have so far restricted distributions; however, the frequency of recent reports suggests that findings of such species resulting from releases of aquarium pets will further increase.

Incomes, Attitudes, and Occurrences of Invasive Species: An Application to Signal Crayfish in Sweden

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Gren, Ing-Marie; Campos, Monica; Edsman, Lennart; Bohman, Patrik

2009-02-01

This article analyzes and carries out an econometric test of the explanatory power of economic and attitude variables for occurrences of the nonnative signal crayfish in Swedish waters. Signal crayfish are a carrier of plague which threatens the native noble crayfish with extinction. Crayfish are associated with recreational and cultural traditions in Sweden, which may run against environmental preferences for preserving native species. Econometric analysis is carried out using panel data at the municipality level with economic factors and attitudes as explanatory variables, which are derived from a simple dynamic harvesting model. A log-normal model is used for the regression analysis, and the results indicate significant impacts on occurrences of waters with signal crayfish of changes in both economic and attitude variables. Variables reflecting environmental and recreational preferences have unexpected signs, where the former variable has a positive and the latter a negative impact on occurrences of waters with signal crayfish. These effects are, however, counteracted by their respective interaction effect with income.

Histological changes and antioxidant enzyme activity in signal crayfish (Pacifastacus leniusculus) associated with sub-acute peracetic acid exposure.

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Chupani, Latifeh; Zuskova, Eliska; Stara, Alzbeta; Velisek, Josef; Kouba, Antonin

2016-01-01

Peracetic acid (PAA) is a powerful disinfectant recently adopted as a therapeutic agent in aquaculture. A concentration of 10 mg L(-1) PAA effectively suppresses zoospores of Aphanomyces astaci, the agent of crayfish plague. To aid in establishing safe therapeutic guideline, the effects of PAA on treated crayfish were investigated through assessment of histological changes and oxidative damage. Adult female signal crayfish Pacifastacus leniusculus (n = 135) were exposed to 2 mg L(-1) and 10 mg L(-1) of PAA for 7 days followed by a 7 day recovery period in clean water. Superoxide dismutase activity was significantly lower in gill and hepatopancreas after three days exposure to 10 mg L(1) PAA than in the group treated with 2 mg L(-1) PAA and a control in only clean water. Catalase activity in gill and hepatopancreas remained unaffected by both exposures. Glutathione reductase was significantly decreased in gill of 10 mg L(-1) PAA treated crayfish and increased in group exposed to 2 mg L(-1) compared to control after 7 days exposure. Antioxidant enzyme activity in exposed groups returned to control values after recovery period. Gill, hepatopancreas, and antennal gland showed slight damage in crayfish treated with 2 mg L(-1) of PAA compared to the control group. The extent and frequency of histological alterations were more pronounced in animals exposed to 10 mg L(-1). The gill was the most affected organ, infiltrated by granular hemocytes and displaying malformations of lamella tips and disorganization of epithelial cells. After a 7 day recovery period, the infiltrating cells in affected tissues of the exposed crayfish began to return to normal levels. Results suggested that the given concentrations could be applied to signal crayfish against crayfish plague agent in aquaculture; however, further studies are required for safe use. Copyright © 2015 Elsevier Ltd. All rights reserved.

REVIEW OF THE NATIONAL RESTOCKING PROGRAMME “ACTIVE PROTECTION OF NATIVE CRAYFISH IN POLAND” 1999-2001

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ŠMIETANA P.

2004-01-01

Full Text Available After the first spread of crayfish plague (aphanomycosis at the end of the nineteenth century, the formerly abundant populations of native crayfish in Poland declined drastically. Analysis of historical data on the occurrence and distribution of crayfish in Poland led to the conclusion that without human intervention the native crayfish species would be at high risk of being made extinct. The largest programme concerning crayfish monitoring and restocking in Poland was “Active protection of native crayfish in Poland” conducted by the Inland Fisheries Institute, the Department of Ecology, University of Szczecin, the Department of Zoology, Warsaw Agricultural University and the University of Warmia and Mazury that was funded by the EkoFundusz Foundation and Inland Fisheries Institute in 1999-2001. One of the main objectives and results of this programme was the determination of indigenous crayfish distribution in Poland (mainly Astacus astacus and Astacus leptodactylus and the restocking of suitable habitats with indigenous crayfish. The densest populations (> 2 500 adult individuals per hectare were used as a source of restocking material. Restocking was performed in 54 water bodies using a total of 45 200 individuals of A. astacus and 9 800 of A. leptodactylus. Between 2001-2002, the success of the restocking programme was monitored. According to the results obtained so far, the restocking exercise has been successful in at least 60.8% of the cases.

Typing methods for the plague pathogen, Yersinia pestis.

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Lindler, Luther E

2009-01-01

Phenotypic and genotypic methodologies have been used to differentiate the etiological agent of plague, Yersinia pestis. Historically, phenotypic methods were used to place isolates into one of three biovars based on nitrate reduction and glycerol fermentation. Classification of Y. pestis into genetic subtypes is problematic due to the relative monomorphic nature of the pathogen. Resolution into groups is dependent on the number and types of loci used in the analysis. The last 5-10 years of research and analysis in the field of Y. pestis genotyping have resulted in a recognition by Western scientists that two basic types of Y. pestis exist. One type, considered to be classic strains that are able to cause human plague transmitted by the normal flea vector, is termed epidemic strains. The other type does not typically cause human infections by normal routes of infection, but is virulent for rodents and is termed endemic strains. Previous classification schemes used outside the Western hemisphere referred to these latter strains as Pestoides varieties of Y. pestis. Recent molecular analysis has definitely shown that both endemic and epidemic strains arose independently from a common Yersinia pseudotuberculosis ancestor. Currently, 11 major groups of Y. pestis are defined globally.

A SURVEY OF THE WHITE-CLAWED CRAYFISH,AUSTROPOTAMOBIUS PALLIPES (LEREBOULLET, AND OF WATERQUALITY IN TWO CATCHMENTS OF EASTERN IRELAND.

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DEMERS A.

2002-07-01

Full Text Available The white-clawed crayfish, Austropotamobius pallipes (Lereboullet, is the only crayfish species found in Ireland. Because of the prohibition on importation of exotic species of crayfish onto the island and of its relatively clean rivers up to now, Ireland has kept an abundant population of crayfish. A survey was conducted in the catchments of the Liffey and Boyne rivers, in eastern Ireland to assess water quality and to sample crayfish populations. The aim of the study was to evaluate the water quality requirements of the white-clawed crayfish in Ireland. Baited traps and nets were used to sample crayfish while water quality was measured with biological indices calculated from samples of macroinvertebrates. Distribution of this crayfish species is patchy in the Liffey catchment and seems to be related to factors such as soil types and water quality. They were not found in the downstream part of the river Liffey possibly due to poor water quality. In the Boyne catchment, no crayfish were found in most of the catchment. They were only present in the Kells Blackwater subcatchment. This may be due to an earlier outbreak of the fungal plague caused by Aphanomyces astaci. The disease was discovered in lakes at the top of some of the tributaries of the Boyne in 1987 and it probably spread from there through the whole catchment.

Plague in China 2014-All sporadic case report of pneumonic plague.

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Li, Yun-Fang; Li, De-Biao; Shao, Hong-Sheng; Li, Hong-Jun; Han, Yue-Dong

2016-02-19

Yersinia pestis is the pathogen of the plague and caused three pandemics worldwide. Pneumonic plague is rarer than bubonic and septicemic plague. We report detailed clinical and pathogenic data for all the three sporadic cases of pneumonic plagues in China in 2014. All the three patients are herders in Gansu province of China. They were all infected by Yersinia pestis and displayed in the form of pneumonic plague respectively without related. We tested patient specimens from the upper (nasopharyngeal swabs) or the lower (sputum) respiratory tract and whole blood, plasma, and serum specimens for Yersinia pestis. All patients had fever, cough and dyspnea, and for patient 2 and 3, unconscious. Respiratory symptoms were predominant with acute respiratory failure. The chest X-ray showed signs consistent with necrotizing inflammation with multiple lobar involvements. Despite emergency treatment, all patients died of refractory multiple organ failure within 24 h after admission to hospital. All the contacts were quarantined immediately and there were no secondary cases. Nowadays, the plague is epidemic in animals and can infect people who contact with the infected animals which may cause an epidemic in human. We think dogs maybe an intermediate vector for plague and as a source of risk for humans who are exposed to pet animals or who work professionally with canines. If a patient has been exposed to a risk factor and has fever and dyspnea, plague should be considered. People who had contact with a confirmed case should be isolated and investigated for F1 antigen analysis and receive post-exposure preventive treatment. A vaccination strategy might be useful for individuals who are occupationally exposed in areas where endemically infected reservoirs of plague-infected small mammals co-exist.

High throughput, multiplexed pathogen detection authenticates plague waves in medieval Venice, Italy.

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Tran, Thi-Nguyen-Ny; Signoli, Michel; Fozzati, Luigi; Aboudharam, Gérard; Raoult, Didier; Drancourt, Michel

2011-03-10

Historical records suggest that multiple burial sites from the 14th-16th centuries in Venice, Italy, were used during the Black Death and subsequent plague epidemics. High throughput, multiplexed real-time PCR detected DNA of seven highly transmissible pathogens in 173 dental pulp specimens collected from 46 graves. Bartonella quintana DNA was identified in five (2.9%) samples, including three from the 16th century and two from the 15th century, and Yersinia pestis DNA was detected in three (1.7%) samples, including two from the 14th century and one from the 16th century. Partial glpD gene sequencing indicated that the detected Y. pestis was the Orientalis biotype. These data document for the first time successive plague epidemics in the medieval European city where quarantine was first instituted in the 14th century.

High Throughput, Multiplexed Pathogen Detection Authenticates Plague Waves in Medieval Venice, Italy

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Tran, Thi-Nguyen-Ny; Signoli, Michel; Fozzati, Luigi; Aboudharam, Gérard; Raoult, Didier; Drancourt, Michel

2011-01-01

Background Historical records suggest that multiple burial sites from the 14th–16th centuries in Venice, Italy, were used during the Black Death and subsequent plague epidemics. Methodology/Principal Findings High throughput, multiplexed real-time PCR detected DNA of seven highly transmissible pathogens in 173 dental pulp specimens collected from 46 graves. Bartonella quintana DNA was identified in five (2.9%) samples, including three from the 16th century and two from the 15th century, and Yersinia pestis DNA was detected in three (1.7%) samples, including two from the 14th century and one from the 16th century. Partial glpD gene sequencing indicated that the detected Y. pestis was the Orientalis biotype. Conclusions These data document for the first time successive plague epidemics in the medieval European city where quarantine was first instituted in the 14th century. PMID:21423736

Effects of depth and crayfish size on predation risk and foraging profitability of a lotic crayfish

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Flinders, C.A.; Magoulick, D.D.

2007-01-01

We conducted field surveys and experiments to determine whether observed distributions of crayfish among habitats were influenced by differential resource availability, foraging profitability, and predation rates and whether these factors differed with crayfish size and habitat depth. We sampled available food resources (detritus and invertebrates) and shelter as rock substrate in deep (>50 cm) and shallow (<30 cm) habitats. We used an enclosure-exclosure experiment to examine the effects of water depth and crayfish size on crayfish biomass and survival, and to determine whether these factors affected silt accrual, algal abundance (chlorophyll a [chl a]), and detritus and invertebrate biomass (g ash-free dry mass) differently from enclosures without crayfish. We conducted tethering experiments to assess predation on small (13-17 mm carapace length [CL]) and large (23-30 mm CL) Orconectes marchandi and to determine whether predation rates differed with water depth. Invertebrate biomass was significantly greater in shallow water than in deep water, whereas detritus biomass did not differ significantly between depths. Cobble was significantly more abundant in shallow than in deep water. Depth and crayfish size had a significant interactive effect on change in size of enclosed crayfish when CL was used as a measure of size but not when biomass was used as a measure of size. CL of small crayfish increased significantly more in enclosures in shallow than in deep water, but CL of large crayfish changed very little at either depth. Silt, chl a, and detritus biomass were significantly lower on tiles in large- than in small- and no-crayfish enclosures, and invertebrate biomass was significantly lower in large- than in no-crayfish enclosures. Significantly more crayfish were consumed in deep than in shallow water regardless of crayfish size. Our results suggest that predation and resource availability might influence the depth distribution of small and large crayfish. Small

[Genodiagnosis and molecular typing of the pathogens for plague, cholera, and anthrax].

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Kutyrev, V V; Smirnova, N I

2003-01-01

The paper contains a survey of published data about the use of DNA-diagnostics in indicating and identifying the causative agents of highly dangerous infections like plague, cholera and anthrax. A discussion of data about the genetic relationship between strains of the mentioned causative agents isolated from different sources by using the molecular-typing methods as well as about the evolution ties between strains of different origins is in the focus of attention. Results of comparative studies of nucleotide sequences of genomes or of individual genomes in different Yersinia pestis, Vibrio cholerae and Bacillus anthracis strains, which are indicative of the evolution of their pathogenicity, are also under discussion.

Antibacterial activity of hemocyanin from red swamp crayfish (Procambarus clarkii).

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Qin, Zhendong; Babu, V Sarath; Wan, Quanyuan; Muhammad, Asim; Li, Jun; Lan, Jiangfeng; Lin, Li

2018-04-01

Hemocyanins (HMC): the copper-containing respiratory proteins present in invertebrate hemolymph, which plays many essential roles in the immune system. Currently, little is known about the HMC domains of Procambarus clarkii (P. clarkii) and their function in antimicrobial immune response. In this present study, we comparatively studied the expression pattern of native PcHMC with the three recombinant proteins of variable domains of crayfish hemocyanin (PcHMC-N, N-terminal domain of hemocyanin; PcHMC-T, tyrosinase domain of hemocyanin; PcHMC-C, C-terminal domain of hemocyanin). The results showed that three purified recombinant proteins had a strong binding to various bacteria and lipopolysaccharides that further highly agglutinated. The HMCs recombinant proteins showed strong antibacterial activity against V. parahaemolyticus and S. aureus by bacterial growth inhibition, phenoloxidase (PO) and phagocytosis assays. Specifically, rPcHMC1-T and rPcHMC1-C inhibited both the bacteria efficiently, rPcHMC1-T was highly upregulated the PO activity than the other recombinant proteins. Whereas, recombinant proteins pretreated crayfish hemocytes participated in phagocytosis activity, rPcHMC1-N and rPcHMC1-C proteins had a profound effect than the rPcHMC1-T on S. aureus and V. parahaemolyticus phagocytosis. The crayfish hemocyanin domains clearly exhibited antibacterial and phagocytic activities against both the bacteria, suggesting that its variable domains of hemocyanin have the different function on specific pathogen during the assault of pathogens. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Macro- and microevolution as related to the problem of origin and global expansion of the plague pathogen Yersinia pestis].

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Suntsov, V V; Suntsova, N I

2008-01-01

The ratio of macro- and microevolutionary processes is considered with reference to the ecological scenario of the origin of the plague pathogen and its subsequent natural and anthropogenic global expansion. The macroevolutionary transformation of the ancestral pseudotuberculosis microbe clone into the initial plague microbe Yersinia pestis tarbagani occurred in Central Asia at the end of the Late Pleistocene by a "vertical" Darwinian way in an inadaptive heterothermal continual intermediate environment--the Mongolian marmot Marmota sibirica-flea Oropsylla silantiewi system--via a sequence of unstable and currently extinct intermediate forms. Its natural geographic expansion on the "oil spot" principle in the postglacial time led to the microevolutionary formation of 20-30 hostal subspecies circulating in populations of the background species of burrowing rodents and pikas in arid areas of Eurasia. The intercontinental spread of the "marmot" and "rat" pathogen subspecies in the past few centuries has been exclusively anthropogenic, with the involvement of synanthropic (ship) rats.

Acute toxicity of chlorantraniliprole to non-target crayfish (Procambarus clarkii) associated with rice-crayfish cropping systems.

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Barbee, Gary C; McClain, W Ray; Lanka, Srinivas K; Stout, Michael J

2010-09-01

Chlorantraniliprole, a novel anthranilic diamide insecticide, was recently introduced into the United States where rice-crayfish crop rotations are practiced to control rice water weevil (Lissorhoptrus oryzophilus Kuschel) infestations. Chlorantraniliprole has high margins of mammalian safety and excellent insecticidal efficacy, but its toxicity to non-target crayfish is uncertain. In this study, the acute toxicity of chlorantraniliprole to the red swamp crayfish Procambarus clarkii Girard was determined using aquatic and feeding assays. The aquatic 96 h median lethal toxicity (LC(50)) data indicate that technical-grade chlorantraniliprole is highly toxic (US EPA category) to crayfish with an LC(50) of 951 microg L(-1) (95% CL = 741-1118 microg L(-1)). A no observed effect concentration (NOEC) of 480 microg L(-1) was recorded. Neither the 36 day chronic feeding study, where crayfish fed on chlorantraniliprole-treated rice seed in aquaria, nor the 144 h acute feeding test, where crayfish fed on rice seeds treated with chlorantraniliprole, produced mortality or abnormal behavior. Chlorantraniliprole is three orders of magnitude less acutely toxic to P. clarkii than lambda-cyhalothrin and etofenprox, two pyrethroid insecticides also used in rice, and is less likely to cause acute crayfish toxicity in rice pond ecosystems. Based on acute toxicity data, the use of chlorantraniliprole should be more compatible with rice-crayfish crop rotations than pyrethroids. (c) 2010 Society of Chemical Industry.

Pneumonic Plague: The Darker Side of Yersinia pestis.

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Pechous, Roger D; Sivaraman, Vijay; Stasulli, Nikolas M; Goldman, William E

2016-03-01

Inhalation of the bacterium Yersinia pestis results in primary pneumonic plague. Pneumonic plague is the most severe manifestation of plague, with mortality rates approaching 100% in the absence of treatment. Its rapid disease progression, lethality, and ability to be transmitted via aerosol have compounded fears of the intentional release of Y. pestis as a biological weapon. Importantly, recent epidemics of plague have highlighted a significant role for pneumonic plague during outbreaks of Y. pestis infections. In this review we describe the characteristics of pneumonic plague, focusing on its disease progression and pathogenesis. The rapid time-course, severity, and difficulty of treating pneumonic plague highlight how differences in the route of disease transmission can enhance the lethality of an already deadly pathogen. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Impacts of flow alterations to crayfishes in Southeastern Oklahoma, with an emphasis on the mena crayfish (orconectes menae)

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Brewer, Shannon K.; Dyer, Joseph J.

2016-01-01

Human activities can alter the environment to the point that it is unsuitable to the native species resulting in a loss of biodiversity. Ecologists understand the importance of biodiversity and the conservation of vulnerable species. Species that are narrowly endemic are considered to be particularly vulnerable because they often use specific habitats that are highly susceptible to human disturbance. The basic components of species conservation are 1) delineation of the spatial distribution of the species, 2) understanding how the species interacts with its environment, and 3) employing management strategies based on the ecology of the species. In this study, we investigated several crayfish species endemic to the Ouachita Mountains in Oklahoma and Arkansas. We established the spatial distributions (i.e., range) of the crayfish using Maximum Entropy species distribution modeling. We then investigated crayfish habitat use with quantitative sampling and a paired movement study. Finally, we evaluated the ability of crayfish to burrow under different environmental conditions in a controlled laboratory setting. Crayfish distribution at the landscape scale was largely driven by climate, geology and elevation. In general, the endemic crayfish in this study occurred above 300-m elevation where the geology was dominated by sandstone and shale, and rainfall totals were the highest compared to the rest of the study region. Our quantitative data indicated crayfish did not select for specific habitat types at the reach scale; however, crayfish appeared to continue to use shallow and dry habitat even as the streams dried. Movement by passive integrated transponder (PIT) tagged crayfish was highly variable but crayfish tended to burrow in response to drought rather than migrate to wet habitat. Controlled laboratory experiments revealed smaller substrate size (pebble) restricted crayfish burrowing more than larger substrates (cobble). We also found excess fine sediment restricted

Invasive crayfish in the Pacific Northwest

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Pearl, Christopher A.; McCreary, Brome; Adams, Michael

2011-01-01

Invasive species directly threaten freshwater biodiversity, particularly in regions of high aquatic richness like the Pacific Northwest (PNW). Crayfish are among the most impactful of aquatic invasive species. Invasive crayfish are considered ecosystem engineers due to their ability to alter basic wetland properties, such as reducing vegetation and bank integrity and increasing turbidity. In areas where invasion is advanced, crayfish pose major economic and ecological problems. Crayfish have been widely introduced for aquaculture and can become established in a wide range of habitat conditions. They also may be spread by anglers who use them as bait. Several non-native crayfish are established in the PNW, but the extent of their invasion is not well known. At least two groups are known from scattered sites in the PNW, and both have proven problematic for native species in other parts of the world: Red swamp crayfish (Procambarus clarkii) and several members of the genus Orconectes. Both groups are native to areas of the eastern United States. Both are identified globally as invasives of high concern and appear on the Oregon Department of Fish and Wildlife's "10 Most Unwanted" and the U.S. Forest Service's "Primary Species of Concern" lists for stream systems in the PNW. Despite the presence of introduced crayfish in the PNW and their high potential for negative effects, the scope of their invasion and effects on aquatic systems are not well known. The U.S. Geological Survey (USGS), along with local groups and state agencies, is working to clarify crayfish distribution and to outline which basins may not yet be invaded. Other goals are to improve understanding of habitat associations of invasive crayfish and their potential effects on native crayfish.

Influences of introduced plague on North American mammals: Implications from ecology of plague in Asia

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Biggins, D.E.; Kosoy, M.Y.

2001-01-01

Intercontinental movements of invasive species continue to modify the world's ecosystems. The plague bacterium (Yersinia pestis) has colonized and altered animal communities worldwide but has received much more attention as a human pathogen. We reviewed studies on the ecology of Y. pestis in ancient foci of central Asia and in western North America, where the bacterium apparently has become established much more recently. Although rodent populations on both continents are affected dramatically by epizootics of plague, the epidemiologically important species of Asia demonstrate resistance in portions of their populations, whereas those of North America are highly susceptible. Individual variation in resistance, which is widespread in Asian rodents and allows a microevolutionary response, has been documented in few North American species of rodents. Plague increases costs of sociality and coloniality in susceptible hosts, increases benefits of disease resistance in general, and increases benefits of adaptability to variable environments for species at higher trophic levels. Prairie dogs (Cynomys) epitomize taxa with high risk to plague because prairie dogs have uniformly low resistance to plague and are highly social. Relationships to plague are poorly understood for many North American rodents, but more than one-half of the species of conservation concern occur within the geographic range of plague.

Testing the generality of a trophic-cascade model for plague

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Collinge, S.K.; Johnson, W.C.; Ray, C.; Matchett, R.; Grensten, J.; Cully, J.F.; Gage, K.L.; Kosoy, M.Y.; Loye, J.E.; Martin, A.P.

2005-01-01

Climate may affect the dynamics of infectious diseases by shifting pathogen, vector, or host species abundance, population dynamics, or community interactions. Black-tailed prairie dogs (Cynomys ludovicianus) are highly susceptible to plague, yet little is known about factors that influence the dynamics of plague epizootics in prairie dogs. We investigated temporal patterns of plague occurrence in black-tailed prairie dogs to assess the generality of links between climate and plague occurrence found in previous analyses of human plague cases. We examined long-term data on climate and plague occurrence in prairie dog colonies within two study areas. Multiple regression analyses revealed that plague occurrence in prairie dogs was not associated with climatic variables in our Colorado study area. In contrast, plague occurrence was strongly associated with climatic variables in our Montana study area. The models with most support included a positive association with precipitation in April-July of the previous year, in addition to a positive association with the number of "warm" days and a negative association with the number of "hot" days in the same year as reported plague events. We conclude that the timing and magnitude of precipitation and temperature may affect plague occurrence in some geographic areas. The best climatic predictors of plague occurrence in prairie dogs within our Montana study area are quite similar to the best climatic predictors of human plague cases in the southwestern United States. This correspondence across regions and species suggests support for a (temperature-modulated) trophic-cascade model for plague, including climatic effects on rodent abundance, flea abundance, and pathogen transmission, at least in regions that experience strong climatic signals. ?? 2005 EcoHealth Journal Consortium.

[Yersinia pestis and plague - an update].

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Stock, Ingo

2014-12-01

The plague of man is a severe, systemic bacterial infectious disease. Without antibacterial therapy, the disease is associated with a high case fatality rate, ranging from 40% (bubonic plague) to nearly 100% (septicemic and pneumonic plague). The disease is caused by Yersinia pestis, a non-motile, gram-negative, facultative anaerobic bacterium belonging to the family of Enterobacteriaceae. In nature, Y. pestis has been found in several rodent species and some other small animals such as shrews. Within its reservoir host, Y. pestis circulates via flea bites. Transmission of Y. pestis to humans occurs by the bite of rat fleas, other flea vectors or by non vectorial routes, e. g., handling infected animals or consumption of contaminated food. Human-to-human transmission of the pathogen occurs primarily through aerosol droplets. Compared to the days when plague was a pandemic scourge, the disease is now relatively rare and limited to some rural areas of Africa. During the last ten years, however, plague outbreaks have been registered repea- tedly in some African regions. For treatment of plague, streptomycin is still considered the drug of choice. Chloramphenicol, doxycycline, gentamicin and ciprofloxacin are also promising drugs. Recombinant vaccines against plague are in clinical development.

Comparative acute toxicity of neonicotinoid and pyrethroid insecticides to non-target crayfish (Procambarus clarkii) associated with rice-crayfish crop rotations.

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Barbee, Gary C; Stout, Michael J

2009-11-01

Most insecticides used to control rice water weevil (Lissorhoptrus oryzophilus Kuscel) infestations are pyrethroids. However, pyrethroids are highly toxic to non-target crayfish associated with rice-crayfish crop rotations. One solution to the near-exclusive reliance on pyrethroids in a rice-crayfish pest management program is to incorporate neonicotinoid insecticides, which are insect specific and effective against weevils but not extremely toxic to crayfish. This study aimed to take the first step to assess neonicotinoids as alternatives to pyrethroids in rice-crayfish crop rotations by measuring the acute toxicities of three candidate neonicotinoid insecticides, clothianidin, dinotefuran and thiamethoxam, to juvenile Procambarus clarkii (Girard) crayfish and comparing them with the acute toxicities of two currently used pyrethroid insecticides, lambda-cyhalothrin and etofenprox. Neonicotinoid insecticides are at least 2-3 orders of magnitude less acutely toxic (96 h LC(50)) than pyrethroids to juvenile Procambarid crayfish: lambda-cyhalothrin (0.16 microg AI L(-1)) = etofenprox (0.29 microg AI L(-1)) > clothianidin (59 microg AI L(-1)) > thiamethoxam (967 microg AI L(-1)) > dinotefuran (2032 microg AI L(-1)). Neonicotinoid insecticides appear to be much less hazardous alternatives to pyrethroids in rice-crayfish crop rotations. Further field-level neonicotinoid acute and chronic toxicity testing with crayfish is needed. (c) 2009 Society of Chemical Industry.

Garden ponds as potential introduction pathway of ornamental crayfish

Directory of Open Access Journals (Sweden)

Patoka J.

2014-01-01

Full Text Available The private stocking of ornamental crayfish in garden ponds was discussed in previous studies, but there is a lack of detailed analysis for better understanding of this introduction pathway. The Czech Republic is one of leading EU countries in trade with ornamental crayfish and private garden ponds are popular among people. The crayfish keepers in the country were interviewed by self-administered questionnaire to gather data about principal characteristics of the keepers and detailed information about crayfish breeding that are of interest for conservation managers. Besides of releasing crayfish into garden ponds, alarming illegal behavior such as releasing of juvenile crayfish into the wild, and capturing of indigenous crayfish from wild populations, were registered. Therefore focusing on public education to increase awareness of possible unwanted consequences of crayfish release and introduction of an obligation to inform customers about hazardousness of non-indigenous crayfish species for retailers and wholesalers is recommended.

[ON SOME DEBATABLE PROBLEMS OF THE NATURAL NIDALITY OF PLAGUE].

Science.gov (United States)

Verzhutsky, D B; Balakhonov, S V

2016-01-01

The communication substantiates the opinion that the theory of natural nidality of plague; which is based on the fundamental recognition that fleas play a leading role in the transmission and accumulation of the plague pathogen, cannot be disproved or substantially changed on the alternative weakly reasoned assumptions and hypotheses. All its "bottlenecks" are quite understandable when considering the long-term volumetric materials that have been gathered directly in nature and generalized in multiple publications. Plague is an obligate transmissive infection; its, agent is a highly specialized parasite that is completely associated in its vital activity with the only group of the blood-sucking insects--fleas and that is transmitted through periodic colonization of warm-blooded animals for a short time. All other types of plague microbe persistence in nature are either occasional or minor and do not play any significant role in pathogen persistence in the natural foci of this disease. There are no strong grounds for seriously considering the attempts to revise the main points of the theory of natural nidality of plague, which are widely held in current academic publications.

ROUNDTABLE SESSION 2B: NATIONAL INTERACTIONS BETWEEN NON-INDIGENOUS AND INDIGENOUS CRAYFISH SPECIES

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GHERARDI F.

2002-07-01

Full Text Available The main object of the present essay is to summarise some aspects underlying the interactions between non-indigenous (NICS and indigenous (ICS crayfish species. The discussion has been also extended to the effects exercised by NICS on the natural habitats they occupy. While doing research on the dyads NICS/ICS, one starting point is to extrapolate common traits that make NICS good invaders from the analysis of their biology, ecology and ethology and the comparison with indigenous species. A subsequent step is to switch attention to the understanding of the characteristics that make ecosystems less vulnerable to invasions and then to analyse both the complex interactions of invaders and target communities and the negative and positive impacts exerted by NICS on the occupied habitats. Examples from Sweden, Britain, and Italy have shown that NICS can replace the native species by a combination of several interacting mechanisms. Besides the transmission of the crayfish plague fungus, mechanisms into action include mostly competitive interference, but also diverse life history traits, recruitment failure, differential susceptibility to predation, and reproductive interference. It has been claimed that invasion theory is full of rules of thumb that, having no precise predictive powers, are thus useless to guide reliable public policy. The solution of the prediction problem requires an in-depth study of every potential invader and target community, trespassing the boundaries among disciplines and having a look at crayfish as a whole and not a single entity. The expectation is thus the return to precise and clear empirical generalisations that can be most useful to develop management strategies.

[A new method of therapy for branchiobdellosis in crayfish].

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Lohniský, K

1979-02-01

Crayfish (Astacus fluviatilis Fabricius, 1793) were treated three times with a bath of diluted ammonia water and proflavine for four and six minutes at a temperature of 18 degrees C to get rid of the ectoparasitic worms of Branchiobdella parasita Henle, 1835; the hatching ability of the Branchiobdella parasita eggs was stopped after the treatment. No lethal effect of the bath on the crayfish of 5 to 14 cm was observed, the lethal effect on the young crayfish borne on the uropods of the female crayfish cannot be eliminated: during the baths the young crayfish died (the death rate was approximately 6% of the average fertility of crayfish); the young crayfish may have been damaged during the treatment operations with the crayfish. The bath of diluted ammonia water and proflavine may be recommended for the treatment of branchiobdellosis in crayfish to be planted, or after several-hour storage of crayfish supplied to the market. One replication of the above cycle is sufficient according to the results obtained. The ammonia content in the ammonia water depends also on the duration of storage and on the storage temperature--it can drop during the storage. Therefore the ammonia water should be used as soon as possible after the despatchment from the place of production; the ammonia content should be determined by means of titration before preparing the bath, and according to this content the dilution ratio should be adjusted.

Habitat associations of three crayfish endemic to the Ouachita Mountain Ecoregion

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Dyer, Joseph J.; Brewer, Shannon K.

2018-01-01

Many crayfish are of conservation concern because of their use of unique habitats and often narrow ranges. In this study, we determined fine-scale habitat use by 3 crayfishes that are endemic to the Ouachita Mountains, in Oklahoma and Arkansas. We sampled Faxonius menae (Mena Crayfish), F. leptogonopodus (Little River Creek Crayfish), and Fallicambarus tenuis (Ouachita Mountain Crayfish) from wet and dry erosional channel units of 29 reaches within the Little River catchment. We compared channel-unit and microhabitat selection for each species. Crayfish of all species and life stages selected erosional channel units more often than depositional units, even though these sites were often dry. Accordingly, crayfish at all life stages typically selected the shallowest available microhabitats. Adult crayfish of all species and juvenile Little River Creek Crayfish selected patches of coarse substrate, and all crayfish tended to use the lowest amount of bedrock available. In general, we showed that these endemic crayfish used erosional channel units of streams, even when the channel units were dry. Conservation efforts that protect erosional channel units and mitigate actions that cause channel downcutting to bedrock would benefit these crayfish, particularly during harsh, summer drying periods.

Flea diversity as an element for persistence of plague bacteria in an East African plague focus.

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Rebecca J Eisen

Full Text Available Plague is a flea-borne rodent-associated zoonotic disease that is caused by Yersinia pestis and characterized by long quiescent periods punctuated by rapidly spreading epidemics and epizootics. How plague bacteria persist during inter-epizootic periods is poorly understood, yet is important for predicting when and where epizootics are likely to occur and for designing interventions aimed at local elimination of the pathogen. Existing hypotheses of how Y. pestis is maintained within plague foci typically center on host abundance or diversity, but little attention has been paid to the importance of flea diversity in enzootic maintenance. Our study compares host and flea abundance and diversity along an elevation gradient that spans from low elevation sites outside of a plague focus in the West Nile region of Uganda (~725-1160 m to higher elevation sites within the focus (~1380-1630 m. Based on a year of sampling, we showed that host abundance and diversity, as well as total flea abundance on hosts was similar between sites inside compared with outside the plague focus. By contrast, flea diversity was significantly higher inside the focus than outside. Our study highlights the importance of considering flea diversity in models of Y. pestis persistence.

SHELTER COMPETITION BETWEEN TWO INVASIVE CRAYFISH SPECIES: A LABORATORY STUDY

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ALONSO F.

2006-01-01

Full Text Available Alien crayfishes represent a common threat to aquatic ecosystems. Their spread in Europe is leading to more frequent contacts between different invasive species populations. Shelter can be an important factor in the resulting interactions. A laboratory experiment was designed to analyse the competition for shelter in similarly sized males of two species that show an invasive behaviour in Spain, Pacifastacus leniusculus and Procambarus clarkii. We carried out 24 heterospecific, six-hour trials, with 30 min behavioural observations per hour. Most often, red swamp crayfish were both the first (70.8% and the long-term winner (62.5%. Usually, the long-term winner was the first winner. Whenever shelter was occupied, a passive behaviour by unsheltered individuals was more frequent in signal crayfish than in red swamp crayfish. When both were unsheltered, signal crayfish displayed more often a passive behaviour. Although the observed behaviour might be explained as the result of dominance by the red swamp crayfish over the signal crayfish, shelter availability and class, as well as different growth patterns and population size structures, could change the intensity and the outcome of the encounters in the wild, where signal crayfish usually reach larger sizes than red swamp crayfish.

Impacts of drought and crayfish invasion on stream ecosystem structure and function

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Magoulick, Daniel D.

2014-01-01

Drought and seasonal drying can be important disturbance events in many small streams, leading to intermittent or isolated habitats. Many small streams contain crayfish populations that are often keystone or dominant species in these systems. I conducted an experiment in stream mesocosms to examine the effects of drought and potential ecological redundancy of a native and invasive crayfish species. I examined the effects of drought (drought or control) and crayfish presence (none, native crayfish Orconectes eupunctus or invasive crayfish Orconectes neglectus) on stream mesocosm structure and function (leaf breakdown, community metabolism, periphyton, sediment and chironomid densities) in a fully factorial design. Each mesocosm contained a deep and shallow section, and drought treatments had surface water present (5-cm depth) in deep sections where tiles and leaf packs were placed. Drought and crayfish presence did not interact for any response variable. Drought significantly reduced leaf breakdown, and crayfish presence significantly increased leaf breakdown. However, the native and invasive crayfish species did not differ significantly in their effects on leaf breakdown. Drought significantly reduced primary production and community respiration overall, whereas crayfish presence did not significantly affect primary production and community respiration. Neither drought nor crayfish presence significantly affected periphyton overall. However, drought significantly reduced autotrophic index (AI), and crayfish presence increased AI. Inorganic sediment and chironomid density were not affected by drought, but both were significantly reduced by crayfish presence. O. eupunctus reduced AI and sediment more than O. neglectus did. Neither drought nor crayfish species significantly affected crayfish growth or survival. Drought can have strong effects on ecosystem function, but weaker effects on benthic structure. Crayfish can have strong effects on ecosystem

Disease limits populations: plague and black-tailed prairie dogs

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Cully, Jack F.; Johnson, T.; Collinge, S.K.; Ray, C.

2010-01-01

Plague is an exotic vector-borne disease caused by the bacterium Yersinia pestis that causes mortality rates approaching 100% in black-tailed prairie dogs (Cynomys ludovicianus). We mapped the perimeter of the active portions of black-tailed prairie dog colonies annually between 1999 and 2005 at four prairie dog colony complexes in areas with a history of plague, as well as at two complexes that were located outside the distribution of plague at the time of mapping and had therefore never been affected by the disease. We hypothesized that the presence of plague would significantly reduce overall black-tailed prairie dog colony area, reduce the sizes of colonies on these landscapes, and increase nearest-neighbor distances between colonies. Within the region historically affected by plague, individual colonies were smaller, nearest-neighbor distances were greater, and the proportion of potential habitat occupied by active prairie dog colonies was smaller than at plague-free sites. Populations that endured plague were composed of fewer large colonies (>100 ha) than populations that were historically plague free. We suggest that these differences among sites in colony size and isolation may slow recolonization after extirpation. At the same time, greater intercolony distances may also reduce intercolony transmission of pathogens. Reduced transmission among smaller and more distant colonies may ultimately enhance long-term prairie dog population persistence in areas where plague is present.

Freshwater crayfish invasions in South Africa: past, present and ...

African Journals Online (AJOL)

Freshwater crayfish invasions have been studied around the world, but less so in Africa, a continent devoid of native freshwater crayfish. The present study reviews historical and current information on alien freshwater crayfish species introduced into South Africa and aims to indicate which areas are at risk from invasion.

Antibacterial properties of extracts of Solidago canadensis and their potential use as dietary supplements in red swamp crayfish (Procambarus clarkii

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Manhong YE,Lei ZHANG,Jiaqi GE,Haifeng SUN,Jingjing NI,Shengmei YANG,Wanhong WEI

2015-12-01

Full Text Available Canadian goldenrod (Solidago canadensis is one of the most destructive invasive weeds in South-eastern China. To evaluate its potential application as dietary supplement in red swamp crayfish (Procambarus clarkii, the antibacterial properties of aqueous and ethanol extracts of this plant against three major pathogenic bacteria in crayfish aquaculture were examined. Inhibition zone tests and determination of minimum inhibitory concentration revealed that the extracts had lower antibacterial activity than extracts from two traditional medicinal plants that possess antibacterial properties, garlic (Allium sativum and cortex phellodendri (Phellodendron chinense. However, they did exhibit greater antibacterial effects than extracts from another widely used medicinal plant, Sophora flavescens, and an aquatic weed, Alternanthera philoxeroides. Aqueous extracts of Canadian goldenrod gave greater inhibition than the ethanol extracts. Crayfish fed a diet with 2% these aqueous extracts exhibited significantly higher enzyme activity of alkaline phosphatase, catalase and phenoloxidase (P<0.05. Based on the results of this study, we conclude that aqueous extracts of Canadian goldenrod are highly promising for the development of new dietary supplement for use in crayfish aquaculture.

Paleoproteomics of the Dental Pulp: The plague paradigm.

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Barbieri, Rémi; Mekni, Rania; Levasseur, Anthony; Chabrière, Eric; Signoli, Michel; Tzortzis, Stéfan; Aboudharam, Gérard; Drancourt, Michel

2017-01-01

Chemical decomposition and fragmentation may limit the detection of ancient host and microbial DNA while some proteins can be detected for extended periods of time. We applied paleoproteomics on 300-year-old dental pulp specimens recovered from 16 individuals in two archeological funeral sites in France, comprising one documented plague site and one documented plague-negative site. The dental pulp paleoproteome of the 16 teeth comprised 439 peptides representative of 30 proteins of human origin and 211 peptides representative of 27 proteins of non-human origin. Human proteins consisted of conjunctive tissue and blood proteins including IgA immunoglobulins. Four peptides were indicative of three presumable Yersinia pestis proteins detected in 3/8 dental pulp specimens from the plague-positive site but not in the eight dental pulp specimens collected in the plague-negative site. Paleoproteomics applied to the dental pulp is a new and innovative approach to screen ancient individuals for the detection of blood-borne pathogens and host inflammatory response.

MINIMISING LOSS OF CRAYFISH AND HABITATDURING WORKS ON WATERCOURSES

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PEAY S.

2003-04-01

Full Text Available Works in watercourses with white-clawed crayfish Austropotamobius pallipes cause temporary or permanent loss of habitat and crayfish. Past modifications can also leave waterbodies unfavourable for crayfish, but sometimes there is scope to improve them. Mitigation measures can reduce the impact and reinstate or even improve habitat. Various case studies show measures used during engineering works and some of the problems. Good planning and supervision are vital. The big issues at river and catchment scales (non-indigenous crayfish, disease, water quality and landuse may be higher priorities than provision of habitat at site or reach level; e.g. fencing in pastures improves riparian areas for crayfish and other species. If necessary, there are various options for natural and artificial refuges, but their success depends on flow characteristics, substrate and accessibility. Microhabitat can make the difference between success and failure.

Invasive crayfish threaten the development of submerged macrophytes in lake restoration.

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van der Wal, Jessica E M; Dorenbosch, Martijn; Immers, Anne K; Vidal Forteza, Constanza; Geurts, Jeroen J M; Peeters, Edwin T H M; Koese, Bram; Bakker, Elisabeth S

2013-01-01

Submerged macrophytes enhance water transparency and aquatic biodiversity in shallow water ecosystems. Therefore, the return of submerged macrophytes is the target of many lake restoration projects. However, at present, north-western European aquatic ecosystems are increasingly invaded by omnivorous exotic crayfish. We hypothesize that invasive crayfish pose a novel constraint on the regeneration of submerged macrophytes in restored lakes and may jeopardize restoration efforts. We experimentally investigated whether the invasive crayfish (Procambarus clarkii Girard) affects submerged macrophyte development in a Dutch peat lake where these crayfish are expanding rapidly. Seemingly favourable abiotic conditions for macrophyte growth existed in two 0.5 ha lake enclosures, which provided shelter and reduced turbidity, and in one lake enclosure iron was added to reduce internal nutrient loading, but macrophytes did not emerge. We transplanted three submerged macrophyte species in a full factorial exclosure experiment, where we separated the effect of crayfish from large vertebrates using different mesh sizes combined with a caging treatment stocked with crayfish only. The three transplanted macrophytes grew rapidly when protected from grazing in both lake enclosures, demonstrating that abiotic conditions for growth were suitable. Crayfish strongly reduced biomass and survival of all three macrophyte species while waterfowl and fish had no additive effects. Gut contents showed that crayfish were mostly carnivorous, but also consumed macrophytes. We show that P. clarkii strongly inhibit macrophyte development once favourable abiotic conditions for macrophyte growth are restored. Therefore, expansion of invasive crayfish poses a novel threat to the restoration of shallow water bodies in north-western Europe. Prevention of introduction and spread of crayfish is urgent, as management of invasive crayfish populations is very difficult.

A synthetic phylogeny of freshwater crayfish: insights for conservation

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Owen, Christopher L.; Bracken-Grissom, Heather; Stern, David; Crandall, Keith A.

2015-01-01

Phylogenetic systematics is heading for a renaissance where we shift from considering our phylogenetic estimates as a static image in a published paper and taxonomies as a hardcopy checklist to treating both the phylogenetic estimate and dynamic taxonomies as metadata for further analyses. The Open Tree of Life project (opentreeoflife.org) is developing synthesis tools for harnessing the power of phylogenetic inference and robust taxonomy to develop a synthetic tree of life. We capitalize on this approach to estimate a synthesis tree for the freshwater crayfish. The crayfish make an exceptional group to demonstrate the utility of the synthesis approach, as there recently have been a number of phylogenetic studies on the crayfishes along with a robust underlying taxonomic framework. Importantly, the crayfish have also been extensively assessed by an IUCN Red List team and therefore have accurate and up-to-date area and conservation status data available for analysis within a phylogenetic context. Here, we develop a synthesis phylogeny for the world's freshwater crayfish and examine the phylogenetic distribution of threat. We also estimate a molecular phylogeny based on all available GenBank crayfish sequences and use this tree to estimate divergence times and test for divergence rate variation. Finally, we conduct EDGE and HEDGE analyses and identify a number of species of freshwater crayfish of highest priority in conservation efforts. PMID:25561670

Genome sequence of Yersinia pestis, the causative agent of plague.

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Parkhill, J; Wren, B W; Thomson, N R; Titball, R W; Holden, M T; Prentice, M B; Sebaihia, M; James, K D; Churcher, C; Mungall, K L; Baker, S; Basham, D; Bentley, S D; Brooks, K; Cerdeño-Tárraga, A M; Chillingworth, T; Cronin, A; Davies, R M; Davis, P; Dougan, G; Feltwell, T; Hamlin, N; Holroyd, S; Jagels, K; Karlyshev, A V; Leather, S; Moule, S; Oyston, P C; Quail, M; Rutherford, K; Simmonds, M; Skelton, J; Stevens, K; Whitehead, S; Barrell, B G

2001-10-04

The Gram-negative bacterium Yersinia pestis is the causative agent of the systemic invasive infectious disease classically referred to as plague, and has been responsible for three human pandemics: the Justinian plague (sixth to eighth centuries), the Black Death (fourteenth to nineteenth centuries) and modern plague (nineteenth century to the present day). The recent identification of strains resistant to multiple drugs and the potential use of Y. pestis as an agent of biological warfare mean that plague still poses a threat to human health. Here we report the complete genome sequence of Y. pestis strain CO92, consisting of a 4.65-megabase (Mb) chromosome and three plasmids of 96.2 kilobases (kb), 70.3 kb and 9.6 kb. The genome is unusually rich in insertion sequences and displays anomalies in GC base-composition bias, indicating frequent intragenomic recombination. Many genes seem to have been acquired from other bacteria and viruses (including adhesins, secretion systems and insecticidal toxins). The genome contains around 150 pseudogenes, many of which are remnants of a redundant enteropathogenic lifestyle. The evidence of ongoing genome fluidity, expansion and decay suggests Y. pestis is a pathogen that has undergone large-scale genetic flux and provides a unique insight into the ways in which new and highly virulent pathogens evolve.

Cethromycin-mediated protection against the plague pathogen Yersinia pestis in a rat model of infection and comparison with levofloxacin.

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Rosenzweig, Jason A; Brackman, Sheri M; Kirtley, Michelle L; Sha, Jian; Erova, Tatiana E; Yeager, Linsey A; Peterson, Johnny W; Xu, Ze-Qi; Chopra, Ashok K

2011-11-01

The Gram-negative plague bacterium, Yersinia pestis, has historically been regarded as one of the deadliest pathogens known to mankind, having caused three major pandemics. After being transmitted by the bite of an infected flea arthropod vector, Y. pestis can cause three forms of human plague: bubonic, septicemic, and pneumonic, with the latter two having very high mortality rates. With increased threats of bioterrorism, it is likely that a multidrug-resistant Y. pestis strain would be employed, and, as such, conventional antibiotics typically used to treat Y. pestis (e.g., streptomycin, tetracycline, and gentamicin) would be ineffective. In this study, cethromycin (a ketolide antibiotic which inhibits bacterial protein synthesis and is currently in clinical trials for respiratory tract infections) was evaluated for antiplague activity in a rat model of pneumonic infection and compared with levofloxacin, which operates via inhibition of bacterial topoisomerase and DNA gyrase. Following a respiratory challenge of 24 to 30 times the 50% lethal dose of the highly virulent Y. pestis CO92 strain, 70 mg of cethromycin per kg of body weight (orally administered twice daily 24 h postinfection for a period of 7 days) provided complete protection to animals against mortality without any toxic effects. Further, no detectable plague bacilli were cultured from infected animals' blood and spleens following cethromycin treatment. The antibiotic was most effective when administered to rats 24 h postinfection, as the animals succumbed to infection if treatment was further delayed. All cethromycin-treated survivors tolerated 2 subsequent exposures to even higher lethal Y. pestis doses without further antibiotic treatment, which was related, in part, to the development of specific antibodies to the capsular and low-calcium-response V antigens of Y. pestis. These data demonstrate that cethromycin is a potent antiplague drug that can be used to treat pneumonic plague.

Oral vaccination against plague using Yersinia pseudotuberculosis.

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Demeure, Christian E; Derbise, Anne; Carniel, Elisabeth

2017-04-01

Yersinia pestis, the agent of plague, is among the deadliest bacterial pathogens affecting humans, and is a potential biological weapon. Because antibiotic resistant strains of Yersinia pestis have been observed or could be engineered for evil use, vaccination against plague might become the only means to reduce mortality. Although plague is re-emerging in many countries, a vaccine with worldwide license is currently lacking. The vaccine strategy described here is based on an oral vaccination with an attenuated strain of Yersinia pseudotuberculosis. Indeed, this species is genetically almost identical to Y. pestis, but has a much lower pathogenicity and a higher genomic stability. Gradual modifications of the wild-type Yersinia pseudotuberculosis strain IP32953 were performed to generate a safe and immunogenic vaccine. Genes coding for three essential virulence factors were deleted from this strain. To increase cross-species immunogenicity, an F1-encapsulated Y. pseudotuberculosis strain was then generated. For this, the Y. pestis caf operon, which encodes F1, was inserted first on a plasmid, and subsequently into the chromosome. The successive steps achieved to reach maximal vaccine potential are described, and how each step affected bacterial virulence and the development of a protective immune response is discussed. The final version of the vaccine, named VTnF1, provides a highly efficient and long-lasting protection against both bubonic and pneumonic plague after a single oral vaccine dose. Since a Y. pestis strain deprived of F1 exist or could be engineered, we also analyzed the protection conferred by the vaccine against such strain and found that it also confers full protection against the two forms of plague. Thus, the properties of VTnF1 makes it one of the most efficient candidate vaccine for mass vaccination in tropical endemic areas as well as for populations exposed to bioterrorism. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Signal crayfish as zoogeomorphic agents: diel patterns of fine sediment suspension in a crayfish-affected river and the implications for fine sediment fluxes and dynamics

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Rice, Stephen; Johnson, Matthew; Reeds, Jake; Longstaff, Holly; Extence, Chris

2013-04-01

The signal crayfish (Pacifasticus leniusculus) is a formidable invasive species that has had a deleterious impact on native freshwater fauna across Europe. We contend that the impact of this animal extends beyond ecology into geomorphology and hypothesise that crayfish are significant agents of fine sediment recruitment and mobilisation, with potentially profound impacts on water quality, substrate quality and fine sediment fluxes. Building on pioneering work by colleagues at Queen Mary University, London this poster considers the role of crayfish in fine sediment suspension in a lowland, gravel-bed river. The hypothesis that nocturnal increases in crayfish activity are associated with a greater frequency of sediment suspension events and increases in ambient turbidity, is tested. Strong diel fluctuations in water turbidity were recorded at several sites on the Brampton Arm of the River Nene in England, a river heavily populated by signal crayfish, during August and September 2012. With the exception of three summer flood events, stage measurements during the same period were essentially flat, ruling out a hydraulic cause for overnight rises in turbidity. Water samples collected at midnight and at midday at one site confirm this diel pattern for suspended sediment concentration. Higher mean turbidity values overnight are associated with an increase in the magnitude and frequency of isolated turbidity spikes or events and this is consistent with crayfish nocturnalism. In particular, we suspect that turbidity events are caused by the construction and maintenenance of burrows and by interactions between crayfish and the river bed while foraging, fighting and avoiding each other. Tying the diel SSC signal directly to crayfish activity proved difficult, but several lines of argument presented here suggest that crayfish are the most likely cause of the diel pattern. These results provide substantial support for the idea that signal crayfish are important zoogeomorphic

Visual shape recognition in crayfish as revealed by habituation.

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Cinzia Chiandetti

2017-08-01

Full Text Available To cope with the everyday challenges that they encounter in their evolutionary niche, crayfish are considered to rely mainly on chemical information or, alternatively, on tactile information, but not much on vision. Hence, research has focused on chemical communication, whereas crayfish visual abilities remain poorly understood and investigated. To fill in this gap, we tested whether crayfish (Procambarus clarkii can distinguish between two different visual shapes matched in terms of luminance. To this aim, we measured both the habituation response to a repeated presentation of a given shape, a downright Y, and the response recovery when a novel shape was presented. The novel shape could be either a Möbius or the same Y-shape but upright rotated. Our results demonstrate that, after habituation to the downright Y, crayfish showed a significantly higher response recovery to the Möbius as compared to the upright rotated Y. Hence, besides relying on chemo-haptic information, we found that crayfish can use sight alone to discriminate between different abstract geometrical shapes when macroscopically different. Failure to discriminate between the downright Y and its inversion or a generalization from the presence of a shape with three points creating a simple category, are both likely parsimonious explanations that should be investigated systematically in further studies. A future challenge will be understanding whether crayfish are capable of generalized shape recognition.

Molecular history of plague.

Science.gov (United States)

Drancourt, M; Raoult, D

2016-11-01

Plague, a deadly zoonose caused by the bacterium Yersinia pestis, has been firmly documented in 39 historical burial sites in Eurasia that date from the Bronze Age to two historical pandemics spanning the 6th to 18th centuries. Palaeomicrobiologic data, including gene and spacer sequences, whole genome sequences and protein data, confirmed that two historical pandemics swept over Europe from probable Asian sources and possible two-way-ticket journeys back from Europe to Asia. These investigations made it possible to address questions regarding the potential sources and routes of transmission by completing the standard rodent and rodent-flea transmission scheme. This suggested that plague was transmissible by human ectoparasites such as lice, and that Y. pestis was able to persist for months in the soil, which is a source of reinfection for burrowing mammals. The analyses of seven complete genome sequences from the Bronze Age indicated that Y. pestis was probably not an ectoparasite-borne pathogen in these populations. Further analyses of 14 genomes indicated that the Justinian pandemic strains may have formed a clade distinct from the one responsible for the second pandemic, spanning in Y. pestis branch 1, which also comprises the third pandemic strains. Further palaeomicrobiologic studies must tightly connect with historical and anthropologic studies to resolve questions regarding the actual sources of plague in ancient populations, alternative routes of transmission and resistance traits. Answering these questions will broaden our understanding of plague epidemiology so we may better face the actuality of this deadly infection in countries where it remains epidemic. Copyright © 2016. Published by Elsevier Ltd.

A review of ecological interactions between crayfish and fish, indigenous and introduced

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Reynolds J.D.

2011-05-01

Full Text Available Crayfish (decapods and fish are both long-lived large members of freshwater communities, often functioning as keystone species. This paper reviews interactions between these, with emphasis on the European context. Native crayfish and fish are in ecological balance, which may involve mutual predation, competition and sometimes habitat disturbance. This balance is disrupted by range extensions and translocations of native fish or crayfish into exotic situations. Some fish and crayfish have been translocated globally, chiefly from North America to other continents. Non-indigenous crayfish species (NICS may impact on native fish, just as introduced fish impact on indigenous crayfish species (ICS. Competition between ICS and NICS may result in making the former susceptible to various mechanisms of interaction with fish, indigenous or introduced. In Europe, long-established NICS – signals, spiny-cheek and red swamp crayfish – may occur in greater densities than ICS; they are more tolerant and aggressive and show more interactions with fish. More recent introductions, still restricted in distribution, have not yet received enough study for their impacts to be assessed. Interactions between fish and crayfish in North and South America, Madagascar and Australasia are also explored. Mechanisms of interaction between fish and crayfish include mutual predation, competition for food and spatial resources, food-web alteration and habitat modification. Resultant changes in communities and ecosystems may be physical or biotal, and affect both ecosystem services and exploitation potential.

Parasites of crayfish ( P. clarki ) and lobsters ( Macrobrachium ...

African Journals Online (AJOL)

Studies on parasites of crayfish and lobsters as indicators of metal pollution in Great Kwa River, Nigeria was evaluated using appropriate instruments for determination of Physicochemical parameters and detection of metals. Formol ether centrifugation method was used for isolation of parasites. A total of 150 crayfish and ...

Double blow: Alien crayfish infected with invasive temnocephalan in South African waters

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Louis du Preez

2013-09-01

Full Text Available Trade in live, freshwater crayfish for ornamental markets, as well as for aquaculture, has grown rapidly and has become the major pathway for the introduction of non-indigenous crayfish species to several countries worldwide. Here we report on the first record of the Australian "redclaw" Cherax quadracarinatus in the natural waters of a game reserve in South Africa. To compound the situation, these redclaw crayfish were infected with a non-indigenous temnocephalan flatworm parasite. Both crayfish and temnocephalan were in full breeding condition, with young. Further spreading of this crayfish to the subtropical, water-rich, northern KwaZulu-Natal Province of South Africa and southern Mozambique is predicted. Not only might the crayfish compete with indigenous aquatic invertebrates but the non-host-specific temnocephalan might transfer to local decapods, such as freshwater crabs.

[Origin of the plague microbe Yersinia pestis: structure of the process of speciation].

Science.gov (United States)

Suntsov, V V

2012-01-01

The origin and evolution of the plague microbe Yersinia pestis are considered in the context of propositions of modern Darwinism. It was shown that the plague pathogen diverged from the pseudotuberculous microbe Yersinia pseudotuberculosis O:1b in the mountain steppe landscapes of Central Asia in the Sartan: 22000-15000 years ago. Speciation occurred in the tarbagan (Marmota sibirica)--flea (Oropsylla silantiewi) parasitic system. The structure of the speciation process included six stages: isolation, genetic drift, enhancement of intrapopulational polymorphism, the beginning of pesticin synthesis (genetic conflict and emergence of hiatus), specialization (stabilization of characteristics), and adaptive irradiation (transformation of the monotypic species Y. pestis tarbagani into a polytypic species). The scenario opens up wide prospects for construction of the molecular phylogeny of the plague microbe Y. pestis and for investigation of the biochemical and molecular-genetic aspects of "Darwinian" evolution of pathogens from many other nature-focal infections.

[The epidemiology and etiology research of Tibetan sheep plague in Qinghai plateau].

Science.gov (United States)

Wei, Baiqing; Xiong, Haoming; Yang, Xiaoyan; Yang, Yonghai; Qi, Meiying; Jin, Juan; Xin, Youquan; Li, Xiang; Yang, Hanqing; Han, Xiumin; Dai, Ruixia

2015-03-01

county were genomovar 5 and genomovar 7, while those isolated Delingha region were genomovar 8. Tibetan sheep were vulnerable to plague infection, hence causing human plague as the infectious source. The Yersinia pestis strains isolated from Tibetan sheep plague carried pathogen characteristics of Qinghai-Tibet plateau plague, developing many new characteristics of such plague.

Outbreak of Plague in a High Malaria Endemic Region - Nyimba District, Zambia, March-May 2015.

Science.gov (United States)

Sinyange, Nyambe; Kumar, Ramya; Inambao, Akatama; Moonde, Loveness; Chama, Jonathan; Banda, Mapopa; Tembo, Elliot; Nsonga, Beron; Mwaba, John; Fwoloshi, Sombo; Musokotwane, Kebby; Chizema, Elizabeth; Kapin'a, Muzala; Hang'ombe, Benard Mudenda; Baggett, Henry C; Hachaambwa, Lottie

2016-08-12

Outbreaks of plague have been recognized in Zambia since 1917 (1). On April 10, 2015, Zambia's Ministry of Health was notified by the Eastern Provincial Medical Office of possible bubonic plague cases in Nyimba District. Eleven patients with acute fever and cervical lymphadenopathy had been evaluated at two rural health centers during March 28-April 9, 2015; three patients died. To confirm the outbreak and develop control measures, the Zambia Ministry of Health's Field Epidemiology Training Program (ZFETP) conducted epidemiologic and laboratory investigations in partnership with the University of Zambia's schools of Medicine and Veterinary Medicine and the provincial and district medical offices. Twenty-one patients with clinically compatible plague were identified, with symptom onset during March 26-May 5, 2015. The median age was 8 years, and all patients were from the same village. Blood specimens or lymph node aspirates from six (29%) patients tested positive for Yersinia pestis by polymerase chain reaction (PCR). There is an urgent need to improve early identification and treatment of plague cases. PCR is a potential complementary tool for identifying plague, especially in areas with limited microbiologic capacity. Twelve (57%) patients, including all six with PCR-positive plague and all three who died, also tested positive for malaria by rapid diagnostic test (RDT). Plague patients coinfected with malaria might be misdiagnosed as solely having malaria, and appropriate antibacterial treatment to combat plague might not be given, increasing risk for mortality. Because patients with malaria might be coinfected with other pathogens, broad spectrum antibiotic treatment to cover other pathogens is recommended for all children with severe malaria, until a bacterial infection is excluded.

Different aspects of reproduction strategies in crayfish: A review

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Yazicioglu B.

2016-01-01

Full Text Available Study of the reproductive strategy of crayfish species is of great importance in the current astacological world. Crayfish are among the largest freshwater invertebrates, and as keystone species, they are able to regulate the structure of the benthic fauna in the freshwaters, demonstrating different ecological strategies and life spans ranging up to 20+ years. In order to bring together the various pieces of information related to this issue, this overview of published scientific reports was conducted. The majority of crayfish species studied show sexual dimorphism, with approximately equal numbers of males and females. However, over some decades numerous observations have been made for a few species that may have different modes of reproduction, such as hermaphroditism or intersex (e.g. Cherax quadricarinatus, Samastacus spinifrons, Parastacus virilastacus and Pacifastacus leniusculus and parthenogenesis (only Procambarus fallax f. virginalis. A recent study showed a new case of parthenogenesis as apomictic parthenogenesis (only Orconectes limosus. In addition, there are many investigations into the reproduction biology of crayfish, including using eyestalk ablation or androgenic gland ablation under various lab conditions and hybridization under natural conditions (e.g. Astacus astacus X Astacus leptodactylus, Orconectes rusticus X Orconectes propinquus. There are also some chemical factors which could possibly affect the reproduction system of crayfish in the wild.

The potential for using red claw crayfish and hybrid African catfish as ...

African Journals Online (AJOL)

The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After 15 days, both crayfish and ...

Plague: Frequently Asked Questions

Science.gov (United States)

... a vaccine available to prevent plague? What is plague? Plague is an infectious disease that affects rodents, ... United States. How do people become infected with plague? People most commonly acquire plague when they are ...

Do culverts impact the movements of the endangered white-clawed crayfish?

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Louca V.

2014-01-01

Full Text Available Culverts can impact the migration and dispersal of aquatic animals and result in population fragmentation, increasing the risk of local extinction for endangered species such as the white-clawed crayfish Austropotamobius pallipes. This study used radio telemetry and passive integrated transponder (PIT telemetry to determine whether existing and experimental covered culverts affect the upstream and downstream movements of adult white-clawed crayfish. Daily crayfish movement rates did not differ significantly between an unlit 363-m long culvert and open stream channel sections. Crayfish moved into dark, covered sections volitionally. However, limited upstream movement occurred at sudden transitions of bed height or smooth-concrete box culvert sections with fast flow, suggesting partial barrier effects. In the 20-m long experimental in-stream culvert, also dark, but with natural stream bed, 70% of radio-tagged crayfish released downstream entered the culvert, as did 60% of those released upstream. Overall 35% passed through, with similar numbers in each direction. We conclude that dark culverts up to several hundred metres do not inhibit dispersal of white-clawed crayfish, provided stream slope, bed type and water velocity are amenable for movement and refuge. Care is required to ensure that culverts are bioengineered to ensure that average water velocity is sufficiently low and local hydraulic variation high, the bed and/or sidewalls contain refuge structures, and there are no cross-channel steps in bed level. Smooth-bedded box culverts are unlikely to be suitable for white-clawed crayfish.

Intensive removal of signal crayfish (Pacifastacus leniusculus) from rivers increases numbers and taxon richness of macroinvertebrate species.

Science.gov (United States)

Moorhouse, Tom P; Poole, Alison E; Evans, Laura C; Bradley, David C; Macdonald, David W

2014-02-01

Invasive species are a major cause of species extinction in freshwater ecosystems, and crayfish species are particularly pervasive. The invasive American signal crayfish Pacifastacus leniusculus has impacts over a range of trophic levels, but particularly on benthic aquatic macroinvertebrates. Our study examined the effect on the macroinvertebrate community of removal trapping of signal crayfish from UK rivers. Crayfish were intensively trapped and removed from two tributaries of the River Thames to test the hypothesis that lowering signal crayfish densities would result in increases in macroinvertebrate numbers and taxon richness. We removed 6181 crayfish over four sessions, resulting in crayfish densities that decreased toward the center of the removal sections. Conversely in control sections (where crayfish were trapped and returned), crayfish density increased toward the center of the section. Macroinvertebrate numbers and taxon richness were inversely correlated with crayfish densities. Multivariate analysis of the abundance of each taxon yielded similar results and indicated that crayfish removals had positive impacts on macroinvertebrate numbers and taxon richness but did not alter the composition of the wider macroinvertebrate community. Synthesis and applications: Our results demonstrate that non-eradication-oriented crayfish removal programmes may lead to increases in the total number of macroinvertebrates living in the benthos. This represents the first evidence that removing signal crayfish from riparian systems, at intensities feasible during control attempts or commercial crayfishing, may be beneficial for a range of sympatric aquatic macroinvertebrates.

FEEDING PREFERENCES OF THE INVASIVE CRAYFISH, PROCAMBARUS CLARKII

Directory of Open Access Journals (Sweden)

Gherardi Francesca

2007-10-01

Full Text Available This laboratory study analyzes feeding preferences of a crayfish species with high invasive potentials, the red swamp crayfish Procambarus clarkii. We first conducted a series of multiple-choice tests among fresh plants (3 tests, one per each of three seasons, i.e. spring, summer, and autumn and animals (1 test in summer. In the first tests, crayfish were simultaneously offered fresh pieces of seven plants of different growth forms and taxonomic groups, selected on the basis of their availability in the habitat. In the second test, the offered animals were dead earthworms, rainbow trout fry, and toad tadpoles. Then, a binary choice test was run in autumn between the most preferred plant (Urtica sp. and earthworms. The percentages of organic C and N contents were measured for each food category using a gas-chromatography technique and the assimilation efficiency of both dry mass and organic content was assessed in a dedicated experiment. The results showed that P. clarkii is selective when offered fresh plants, consuming a relatively larger biomass of Urtica (in the three seasons examined, green algae (in spring, and Polygonum (in summer and autumn. Surprisingly, crayfish did not exhibit preference for any animal prey. Also, P. clarkii’s feeding decisions seemed not to be associated with either the availability of plants in the habitat or their occurrence in the gut contents of wild crayfish. Neither did their ingested biomass depend on the organic content or assimilation efficiency. Procambarus clarkii preferred Urtica sp. over earthworms, notwithstanding the higher nutritional value and assimilation efficiency of the latter. The above results might suggest that feeding preferences of the species often depend on factors other than nutritional value and digestibility. Future studies will analyze all the possible factors together in order to unravel the rules that govern feeding preferences in crayfish. In the case of invasive species, such

Molecular techniques for characterisation of pathogens

DEFF Research Database (Denmark)

Kampmann, Marie-Louise

Pathogens have always had a major interest to humans due to their central role in sickness and death. Influenza A annually kills at least 250,000 humans, and has been the cause of millions of further deaths during pandemic years in the past. Plague (Yersinia pestis) has been the cause of the Black...... capture for the detection of Y. pestis in samples from the Justinian plague (600 AD) as an attempt to detect this pathogen as a cause of death in the victims....

Distribution of native and exotic branchiobdellidans (Annelida: Clitellata on their respective crayfish hosts in northern Italy, with the first record of native Branchiobdella species on an exotic North American crayfish.

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Joy N. RAYBURN

1999-02-01

Full Text Available Branchiobdellidans were found on crayfish at the 18 sites examined in northern Italy. At 15 of the sites the native crayfish, Austropotamobius pallipes, was collected and all supported specimens of Branchiobdella italica. A few specimens of B. parasita were found at only two of these sites and no specimens of B. hexodonta were observed during the survey. The North American Louisiana red swamp crayfish, Procambarus (Scapulicambarus clarkii has been found in three additional sites around Carmagnola, south of Torino. The exotic Cambarincola mesochoreus was recovered from red crayfish at two sites. However, no specimens of C. mesochoreus were found at the third site, but specimens B. italica and B. parasita were identified. This is the first record of native Branchiobdella spp. on an exotic and wild crayfish in northern Italy.

Plague

Science.gov (United States)

Abbott, Rachel C.; Rocke, Tonie E.

2012-01-01

Plague offers readers an overview of this highly complex disease caused by the bacteria Yersinia pestis. The history of the disease, as well as information about Yersinia pestis and its transmission by fleas, is described. The section Geographic Distribution presents areas of the world and United States where plague occurs most commonly in rodents and humans. Species Susceptibility describes infection and disease rates in rodents, humans, and other animals. Disease Ecology considers the complex relationship among rodents, domestic and wild animals, and humans and explores possible routes of transmission and maintenance of the organism in the environment. The effects of climate change, the potential for Y. pestis to be used as a bioweapon, and the impact of plague on conservation of wildlife are considered in Points to Ponder. Disease Prevention and Control outlines methods of prevention and treatment including vaccination for prairie dogs and black-footed ferrets. A glossary of technical terms is included. Tonie E. Rocke, the senior author and an epizootiologist at the USGS National Wildlife Health Center (NWHC), is a prominent researcher on oral vaccination of prairie dogs to prevent plague. She is currently working to transfer her success in the laboratory to the field to control plague in prairie dogs. Rachel C. Abbott, a biologist at the NWHC, is assisting Dr. Rocke in this process and will coordinate field trials of the vaccine. Milt Friend, first director of the NWHC, wrote the foreword. Plague is intended for scholars and the general public. The material is presented in a simple, straightforward manner that serves both audiences. Numerous illustrations and tables provide easily understood summaries of key points and information.

Assessing the importance of food for improving noble crayfish culture conditions

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Rusch J.C.

2015-01-01

Full Text Available Captive breeding and crayfish culture are considered important measures in species protection activities. Thus, knowledge on optimal feeding of crayfish in captivity is needed in order to secure minimal mortality and prevent detrimental effects to health. To optimize conditions of crayfish prior to subsequent stocking, feeding trials were conducted with the aim of investigating the connection between food intake, food preference and temperature under near natural conditions. During a five-month period, noble crayfish were fed on fish, carrots, algae and chironomid-larvae according to a pre-defined rotation system, whereby the ambient water temperature ranged from 5 °C to 13 °C, following the natural temperature regime. The results of these feeding trials demonstrate a direct correlation between rising temperature and increasing food intake for water temperatures exceeding 8 °C. Food intake is further influenced by the variety of food items available at any one time. The results also confirm that Astacus astacus has a strong preference for fish and that alternation of food types has an impact on consumption. Our results prompt the following recommendations for optimized feeding conditions of crayfish in captivity prior to their release: (1 a balanced diet containing not only plant tissue but also a significant proportion of animal tissue and (2 the amount of available food must be adjusted according to the carapace length of the crayfish.

The Effect of Seasonal Weather Variation on the Dynamics of the Plague Disease

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Rigobert C. Ngeleja

2017-01-01

Full Text Available Plague is a historic disease which is also known to be the most devastating disease that ever occurred in human history, caused by gram-negative bacteria known as Yersinia pestis. The disease is mostly affected by variations of weather conditions as it disturbs the normal behavior of main plague disease transmission agents, namely, human beings, rodents, fleas, and pathogens, in the environment. This in turn changes the way they interact with each other and ultimately leads to a periodic transmission of plague disease. In this paper, we formulate a periodic epidemic model system by incorporating seasonal transmission rate in order to study the effect of seasonal weather variation on the dynamics of plague disease. We compute the basic reproduction number of a proposed model. We then use numerical simulation to illustrate the effect of different weather dependent parameters on the basic reproduction number. We are able to deduce that infection rate, progression rates from primary forms of plague disease to more severe forms of plague disease, and the infectious flea abundance affect, to a large extent, the number of bubonic, septicemic, and pneumonic plague infective agents. We recommend that it is more reasonable to consider these factors that have been shown to have a significant effect on RT for effective control strategies.

Stream permanence influences crayfish occupancy and abundance in the Ozark Highlands, USA

Science.gov (United States)

Yarra, Allyson N.; Magoulick, Daniel D.

2018-01-01

Crayfish use of intermittent streams is especially important to understand in the face of global climate change. We examined the influence of stream permanence and local habitat on crayfish occupancy and species densities in the Ozark Highlands, USA. We sampled in June and July 2014 and 2015. We used a quantitative kick–seine method to sample crayfish presence and abundance at 20 stream sites with 32 surveys/site in the Upper White River drainage, and we measured associated local environmental variables each year. We modeled site occupancy and detection probabilities with the software PRESENCE, and we used multiple linear regressions to identify relationships between crayfish species densities and environmental variables. Occupancy of all crayfish species was related to stream permanence. Faxonius meeki was found exclusively in intermittent streams, whereas Faxonius neglectus and Faxonius luteushad higher occupancy and detection probability in permanent than in intermittent streams, and Faxonius williamsi was associated with intermittent streams. Estimates of detection probability ranged from 0.56 to 1, which is high relative to values found by other investigators. With the exception of F. williamsi, species densities were largely related to stream permanence rather than local habitat. Species densities did not differ by year, but total crayfish densities were significantly lower in 2015 than 2014. Increased precipitation and discharge in 2015 probably led to the lower crayfish densities observed during this year. Our study demonstrates that crayfish distribution and abundance is strongly influenced by stream permanence. Some species, including those of conservation concern (i.e., F. williamsi, F. meeki), appear dependent on intermittent streams, and conservation efforts should include consideration of intermittent streams as an important component of freshwater biodiversity.

MANAGEMENT STRATEGIES, YIELD AND POPULATION DEVELOPMENT OF THE NOBLE CRAYFISH ASTACUS ASTACUS IN LAKE STEINSFJORDEN

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SKURDAL J.

2002-07-01

Full Text Available Lake Steinsfjorden is the most important noble crayfish locality in Norway. The crayfish population has been monitored annually since 1979 including data on total trapping effort, yield and population composition before and after the catching season. The harvest has ranged from 0.7-4.7 kg.ha-1. The catch per trap night decreased prior to 1991 and the yield was reduced by some 50% over the years 1987-1992 as compared to 1979-1986. This was due to removal of small crayfish, high exploitation and the establishment of dense stands of Canadian pondweed (Elodea canadensis. Baited traps catch a large fraction of crayfish < 95 mm total length minimum size. These should according to the regulations immediately be released into the lake. However, it is apparent from the size composition that release of these small crayfish was rather incomplete. In 1983, trap mesh size was increased from 17.5 mm to 21 mm to reduce the fraction of undersized crayfish in the trap catches, yet no effects of this increased mesh size on crayfish size distribution were observed. The legal season has been reduced three times during the study period. In 1983, the closing date was changed from 31 December to 15 September. In 1989 the legal season was further reduced to two weeks and finally in 1995 to 10 days. This reduced total trap effort by 45%. The shorter season allow many crayfish to moult twice instead of once between seasons and the fraction of large crayfish has thus increased and so has the catch per trap night. Canadian pondweed has established dense annual stands and thus has made large parts of the shallow areas unsuitable for crayfish, causing an overall decrease in crayfish population size and production.

Investigation of plutonium concentration and distribution in burrowing crayfish from the White Oak Creek floodplain

International Nuclear Information System (INIS)

Delaney, M.S.; Dahlman, R.C.; Craig, R.B.

1979-01-01

The White Oak floodplain was contaminated with several radionuclides, including 239 Pu, during the Manhattan Project in 1944. Plutonium distribution in the soil is nonhomogeneous. An investigation was conducted to deterine Pu accumulation in a resident animal population. Crayfish were chosen because they complete their life-cycle within the contaminated environment, they directly contact contaminated muds, and they function in a food chain of significance to man. Two major conclusions of the research were that Pu concentrations in contaminated crayfish typically exceed those of control crayfish by two orders of magnitude and that if an incident were to occur in which a standard man ingested the soft tissues of ten crayfish from the floodplain, an insignificant whole body dose would accrue over the subsequent 50 years of life. The digestive tract of contaminated crayfish contained 21 to 33% of the Pu body burden, soft tissues contained 11 to 31% of the Pu body burden, and 48 to 62% of the Pu body burden of contaminated crayfish was associated with the carapace. Therefore, at a molt a large proportion of its accumulated Pu is deposited in the environment. A supplementary laboratory investigation using 237 Pu included a chronic Pu uptake study by uncontaminated crayfish. In these crayfish, from 64 to 82% of the 237 Pu was associated with the body tissues. Complementary data for 237 Pu associated with the carapace ranged from 18 to 37% of the distribution. An inventory of 239 Pu in crayfish at two sites on the floodplain was calculated by multiplying the estimated biomass of the crayfish by their average 239 Pu concentration. This evaluation of Pu associated with the crayfish population was compared to an inventory of 239 Pu in the soil in which they burrow and was found to be eight orders of magnitude less

Investigation of plutonium concentration and distribution in burrowing crayfish from the White Oak Creek floodplain

Energy Technology Data Exchange (ETDEWEB)

Delaney, M.S.; Dahlman, R.C.; Craig, R.B.

1979-01-01

The White Oak floodplain was contaminated with several radionuclides, including /sup 239/Pu, during the Manhattan Project in 1944. Plutonium distribution in the soil is nonhomogeneous. An investigation was conducted to deterine Pu accumulation in a resident animal population. Crayfish were chosen because they complete their life-cycle within the contaminated environment, they directly contact contaminated muds, and they function in a food chain of significance to man. Two major conclusions of the research were that Pu concentrations in contaminated crayfish typically exceed those of control crayfish by two orders of magnitude and that if an incident were to occur in which a standard man ingested the soft tissues of ten crayfish from the floodplain, an insignificant whole body dose would accrue over the subsequent 50 years of life. The digestive tract of contaminated crayfish contained 21 to 33% of the Pu body burden, soft tissues contained 11 to 31% of the Pu body burden, and 48 to 62% of the Pu body burden of contaminated crayfish was associated with the carapace. Therefore, at a molt a large proportion of its accumulated Pu is deposited in the environment. A supplementary laboratory investigation using /sup 237/Pu included a chronic Pu uptake study by uncontaminated crayfish. In these crayfish, from 64 to 82% of the /sup 237/Pu was associated with the body tissues. Complementary data for /sup 237/Pu associated with the carapace ranged from 18 to 37% of the distribution. An inventory of /sup 239/Pu in crayfish at two sites on the floodplain was calculated by multiplying the estimated biomass of the crayfish by their average /sup 239/Pu concentration. This evaluation of Pu associated with the crayfish population was compared to an inventory of /sup 239/Pu in the soil in which they burrow and was found to be eight orders of magnitude less.

A new ostracod (Entocytheridae, Notocytherinae) on New Guinea crayfish1)

NARCIS (Netherlands)

Hart, D.G.; Hart, C.W.

1970-01-01

In 1967 we examined the crayfish collections in the Rijksmuseum van Natuurlijke Historie, Leiden, to determine if the crayfishes collected in New Guinea in 1954 by Dr. L. B. Holthuis, Dr. L. D. Brongersma, and Dr. M. Boeseman (Boeseman, 1963) were hosts to commensal ostracods. Of the collections

EXPERIMENTAL EVIDENCE FOR HOMING IN THE RED SWAMP CRAYFISH, PROCAMBARUS CLARKII

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BARBARESI S.

2006-01-01

Full Text Available The red swamp crayfish, Procambarus clarkii, is an efficient burrower, but its burrow fidelity has been recently questioned. In this study, we aimed at investigating whether individuals of this species are capable to learn the position of a goal (a wet burrow hidden to their sight in experimental tanks and to make more efficient with time their oriented movement towards it. We also analyzed crayfish behavior after having closed one of the two accesses to the goal. Indeed, in successive trials we recorded the crayfish tendency to reduce the distance covered to reach the goal and the time taken, except when they were already familiar to the experimental setting. Memory of the spatial configuration lasted for 16 hours at least and crayfish learned and maintained individual trajectories. The interruption of their usual path always caused a drastic increase of distance and time that however decreased in the successive trials. This study provided also some information of the sensory channels used by P. clarkii to orient. This crayfish, which can be active also during daytime, seemed to adopt a combination of tactile and visual information, together with the possible use of cues (i.e. humidity cues emitted by the goal. Future studies should clarify the paradox of a crayfish species whose individuals, although being physiologically capable to home, seem not to return to the previously occupied burrows at the end of their foraging excursions, notwithstanding the time and energy expended to excavate them.

Plague Symptoms

Science.gov (United States)

... Search Form Controls Cancel Submit Search the CDC Plague Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . Plague Home Ecology & Transmission Symptoms Diagnosis & Treatment Maps & Statistics ...

Novel Insights into Antiviral Gene Regulation of Red Swamp Crayfish, Procambarus clarkii, Infected with White Spot Syndrome Virus

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Shaokui Yi

2017-11-01

Full Text Available White spot syndrome virus (WSSV, one of the major pathogens of Procambarus clarkii, has caused severe disruption to the aquaculture industry of P. clarkii in China. To reveal the gene regulatory mechanisms underlying WSSV infection, a comparative transcriptome analysis was performed among WSSV-infected susceptible individuals (GS, viral resistant individuals (GR, and a non-infected control group (GC. A total of 61,349 unigenes were assembled from nine libraries. Subsequently, 515 and 1033 unigenes exhibited significant differential expression in sensitive and resistant crayfish individuals compared to the control group (GC. Many differentially expressed genes (e.g., C-type lectin 4, Peroxinectin, Prophenoloxidase, and Serine/threonine-protein kinase observed in GR and GS play critical roles in pathogen recognition and viral defense reactions after WSSV infection. Importantly, the glycosaminoglycan biosynthesis-chondroitin sulfate/dermatan sulfate pathway was identified to play critical roles in defense to WSSV infection for resistant crayfish individuals by upregulating the chondroitin sulfate related genes for the synthesis of WSSV-sensitive, functional chondroitin sulfate chains containing E units. Numerous genes and the key pathways identified between resistant and susceptible P. clarkii individuals provide valuable insights regarding antiviral response mechanisms of decapoda species and may help to improve the selective breeding of P. clarkii WSSV-resistance.

Observations on the endemicity of plague in Karatu and Ngorongoro ...

African Journals Online (AJOL)

have been exposed to Yersinia pestis, the plague pathogen, in the recent past. Since home range of rodents is known to be fairly short as previously demonstrated in Muheza, Morogoro and Lushoto districts (Kilonzo, 1984; Leirs, 1992; R.H. Makundi, unpubl.), the current observations can be justifiably interpreted to suggest ...

Spread of plague among black-tailed prairie dogs is associated with colony spatial characteristics

Science.gov (United States)

Johnson, T.L.; Cully, J.F.; Collinge, S.K.; Ray, C.; Frey, C.M.; Sandercock, B.K.

2011-01-01

Sylvatic plague (Yersinia pestis) is an exotic pathogen that is highly virulent in black-tailed prairie dogs (Cynomys ludovicianus) and causes widespread colony losses and individual mortality rates >95%. We investigated colony spatial characteristics that may influence inter-colony transmission of plague at 3 prairie dog colony complexes in the Great Plains. The 4 spatial characteristics we considered include: colony size, Euclidean distance to nearest neighboring colony, colony proximity index, and distance to nearest drainage (dispersal) corridor. We used multi-state mark-recapture models to determine the relationship between these colony characteristics and probability of plague transmission among prairie dog colonies. Annual mapping of colonies and mark-recapture analyses of disease dynamics in natural colonies led to 4 main results: 1) plague outbreaks exhibited high spatial and temporal variation, 2) the site of initiation of epizootic plague may have substantially influenced the subsequent inter-colony spread of plague, 3) the long-term effect of plague on individual colonies differed among sites because of how individuals and colonies were distributed, and 4) colony spatial characteristics were related to the probability of infection at all sites although the relative importance and direction of relationships varied among sites. Our findings suggest that conventional prairie dog conservation management strategies, including promoting large, highly connected colonies, may need to be altered in the presence of plague. ?? 2011 The Wildlife Society.

STUDIES ON THE WHITE-CLAWED CRAYFISH (AUSTROPOTAMOBIUS PALLIPES ASSOCIATED WITH MUDDY HABITATS

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HOLDICH D. M.

2006-01-01

Full Text Available The white-clawed crayfish, Austropotamobius pallipes, is usually found associated with stony habitats containing obvious refuges in the form of gaps between and under rocks, macrophytes and marginal tree roots, particularly in streams and lakes with clear water and little marginal mud. If the banks are composed of suitable material, then they may also construct and live in burrows. However, the white-clawed crayfish is also found to be abundant in streams, rivers, canals and millraces with deep, anoxic mud and with very little aquatic vegetation. Foraging on the surface of mud may be the only way they can obtain sufficient food in the form of macroinvertebrates and decaying plant matter. Where do crayfish live in this restricted habitat? Dewatering such waterways for essential engineering works, such as desilting, bridge and weir repairs, bank reinforcements, and maintenance of outfalls can provide an excellent opportunity to study the available habitat and the crayfish populations, in addition good estimates of population size and age class distribution can be obtained, although, as with other methods, juveniles tend to be underrepresented. A number of case studies will be given to illustrate the fact that white-clawed crayfish are able to colonize muddy habitats in some numbers. The value of retaining trees with their roots hanging into waterways as a refuge for both crayfish and small fish is highlighted.

Are the effects of an invasive crayfish on lake littoral macroinvertebrate communities consistent over time?

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Ruokonen T. J.

2016-01-01

Full Text Available Management of invasive species requires assessment of their effects on recipient ecosystems. However, impact assessment of invasive species commonly lacks a long-term perspective which can potentially lead to false conclusions. We examined the effects of the invasive signal crayfish (Pacifastacus leniusculus Dana on the stony littoral macroinvertebrate communities of a large boreal lake and assessed the extent to which the patterns observed in previous short-term studies were stable over time. We used temporal macroinvertebrate data collected in five consecutive years from a site with a well-established crayfish population, a site with no crayfish and a site where crayfish had been recently introduced. Our results revealed that signal crayfish had temporally rather consistent negative effects on the benthic macroinvertebrate assemblages but that the effects might be limited to certain taxa, in particular Gastropoda and Coleoptera. We also observed increases in Gastropoda density and taxa richness following a decline in crayfish density, indicating that the recovery of invertebrate assemblages might be fast. Hence, negative effects on benthic macroinvertebrates can likely be minimized by effective control of the signal crayfish population.

[A NATURAL PLAGUE FOCUS. IN GORNYI ALTAI: FORMATION, DEVELOPMENT, AND FUNCTIONING].

Science.gov (United States)

Korzun, V M; Balakhoiov, S V; Chpanin, E V; Denisov, A V; Mikhailov, E P; Mischenko, A J; Yarygina, M B; Rozhdestvensky, E N; Fomina, L A

2016-01-01

The paper gives the results of analyzing the data of long-term studies of the natural focal pattern of plague in the Gornyi Altai natural focus. It describes a wide range of biological processes occurring in the focus and shows the most important patterns of its functioning as a complex multilevel ecological system. The key features of the formation of the focus have been revealed. The plague focus in South-Western Altai has formed relatively, recently, about half a century ago, then it has intensively developed and its enzootic area and the activity of epizootic manifestations have considerably increased. This process is due to the space-time transformations of the basic ecological and population characteristics of Pallas' pika (Ochotoma pallasi), the principal vector of the pathogen of plague and fleas parasitizing the mammal, which is in turn related to the aridization of mountain steppes in South-Western Altai.

Wildlife Plague Surveillance Near the China-Kazakhstan Border: 2012-2015.

Science.gov (United States)

Zhao, S-S; Pulati, Y; Yin, X-P; Li, W; Wang, B-J; Yang, K; Chen, C-F; Wang, Y-Z

2017-12-01

Plague is a zoonotic disease caused by the bacterium Yersinia pestis. This pathogen can be transmitted by fleas and has an enzootic cycle, circulating among small mammals, and occasionally epizootic cycles, infecting other species. In China, infected wild rodents are primarily reservoirs of Y. Pestis and are related to human infection (Int. J. Infect. Dis., 33, 2015 and 67; BMC Microbiol., 9, 2009 and 205). Because shepherd dogs prey on and eat rodents (e.g. marmots and mice), they are valuable sentinel animals for plague serosurveillance in endemic disease foci, although their infections are usually asymptomatic (Vet. Microbiol., 172, 2014 and 339). © 2017 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

Zoonoses As Ecological Entities: A Case Review of Plague.

Science.gov (United States)

Zeppelini, Caio Graco; de Almeida, Alzira Maria Paiva; Cordeiro-Estrela, Pedro

2016-10-01

As a zoonosis, Plague is also an ecological entity, a complex system of ecological interactions between the pathogen, the hosts, and the spatiotemporal variations of its ecosystems. Five reservoir system models have been proposed: (i) assemblages of small mammals with different levels of susceptibility and roles in the maintenance and amplification of the cycle; (ii) species-specific chronic infection models; (ii) flea vectors as the true reservoirs; (iii) Telluric Plague, and (iv) a metapopulation arrangement for species with a discrete spatial organization, following a source-sink dynamic of extinction and recolonization with naïve potential hosts. The diversity of the community that harbors the reservoir system affects the transmission cycle by predation, competition, and dilution effect. Plague has notable environmental constraints, depending on altitude (500+ meters), warm and dry climates, and conditions for high productivity events for expansion of the transmission cycle. Human impacts are altering Plague dynamics by altering landscape and the faunal composition of the foci and adjacent areas, usually increasing the presence and number of human cases and outbreaks. Climatic change is also affecting the range of its occurrence. In the current transitional state of zoonosis as a whole, Plague is at risk of becoming a public health problem in poor countries where ecosystem erosion, anthropic invasion of new areas, and climate change increase the contact of the population with reservoir systems, giving new urgency for ecologic research that further details its maintenance in the wild, the spillover events, and how it links to human cases.

Zoonoses As Ecological Entities: A Case Review of Plague.

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Caio Graco Zeppelini

2016-10-01

Full Text Available As a zoonosis, Plague is also an ecological entity, a complex system of ecological interactions between the pathogen, the hosts, and the spatiotemporal variations of its ecosystems. Five reservoir system models have been proposed: (i assemblages of small mammals with different levels of susceptibility and roles in the maintenance and amplification of the cycle; (ii species-specific chronic infection models; (ii flea vectors as the true reservoirs; (iii Telluric Plague, and (iv a metapopulation arrangement for species with a discrete spatial organization, following a source-sink dynamic of extinction and recolonization with naïve potential hosts. The diversity of the community that harbors the reservoir system affects the transmission cycle by predation, competition, and dilution effect. Plague has notable environmental constraints, depending on altitude (500+ meters, warm and dry climates, and conditions for high productivity events for expansion of the transmission cycle. Human impacts are altering Plague dynamics by altering landscape and the faunal composition of the foci and adjacent areas, usually increasing the presence and number of human cases and outbreaks. Climatic change is also affecting the range of its occurrence. In the current transitional state of zoonosis as a whole, Plague is at risk of becoming a public health problem in poor countries where ecosystem erosion, anthropic invasion of new areas, and climate change increase the contact of the population with reservoir systems, giving new urgency for ecologic research that further details its maintenance in the wild, the spillover events, and how it links to human cases.

Distribution of native and exotic branchiobdellidans (Annelida: Clitellata) on their respective crayfish hosts in northern Italy, with the first record of native Branchiobdella species on an exotic North American crayfish.

OpenAIRE

Joy N. RAYBURN; Giovanni B. DELMASTRO; Stuart R. GELDER

1999-01-01

Branchiobdellidans were found on crayfish at the 18 sites examined in northern Italy. At 15 of the sites the native crayfish, Austropotamobius pallipes, was collected and all supported specimens of Branchiobdella italica. A few specimens of B. parasita were found at only two of these sites and no specimens of B. hexodonta were observed during the survey. The North American Louisiana red swamp crayfish, Procambarus (Scapulicambarus) clarkii has been found in three additional sites around Carma...

ZEBRA MUSSEL COLONIZATION OF RUSTY CRAYFISH IN GREEN BAY, LAKE MICHIGAN

Science.gov (United States)

In August, 1995 six rusty crayfish colonized with zebra mussels were captured in small-meshed fyke-nets sets set apart as of a fish sampling effort at Peter's Marsh and Long-Tail Point Wetland in lower Green Bay. Mussels colonized virtually all areas of the crayfish bodies, but ...

Plague Maps and Statistics

Science.gov (United States)

... and Statistics Recommend on Facebook Tweet Share Compartir Plague in the United States Plague was first introduced ... them at higher risk. Reported Cases of Human Plague - United States, 1970-2016 Since the mid–20th ...

Effects of mining-derived metals on riffle-dwelling crayfish in southwestern Missouri and southeastern Kansas, USA

Science.gov (United States)

Allert, Ann L.; DiStefano, Robert J.; Schmitt, Christopher J.; Fairchild, James F.; Brumbaugh, William G.

2012-01-01

Riffle-dwelling crayfish populations were sampled at 16 sites in 4 tributaries of the Spring River located within the Tri-State Mining District in southwest Missouri. Crayfish density, physical habitat quality, and water quality were examined at each site to assess the ecological effects of mining-derived metals on crayfish. Metals (lead, zinc, and cadmium) were analyzed in samples of surface water, sediment, detritus, and whole crayfish. Sites were classified a posteriori into reference, mining, and downstream sites primarily based on metal concentrations in the materials analyzed. Three species of crayfish (Orconectes neglectus neglectus, O. macrus, and O. virilis) were collected during the study; however, only O. n. neglectus was collected at all sites. Mean crayfish densities were significantly lower at mining sites than at reference sites. Mean concentrations of metals were significantly correlated among the materials analyzed and were significantly greater at mining and downstream sites than at reference sites. Principal component analyses showed a separation of sites due to an inverse relationship among crayfish density, metals concentrations, and physical habitat quality variables. Sediment probable-effects quotients and surface-water toxic unit scores were significantly correlated; both indicated risk of toxicity to aquatic biota at several sites. Metals concentrations in whole crayfish at several sites exceeded concentrations known to be toxic to carnivorous wildlife. Mining-derived metals have the potential to impair ecosystem function through decreased organic matter processing and nutrient cycling in streams due to decreased crayfish densities.

WHITE-CLAWED CRAYFISH IN MUDDY HABITATS: MONITORING THE POPULATION IN THE RIVER IVEL, BEDFORDSHIRE, UK

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PEAY S.

2006-01-01

Full Text Available White-clawed crayfish Austropotamobius pallipes are usually associated with stony substrates, tree roots, or refuges in submerged banks. The River Ivel has the last known population of white-clawed crayfish in Bedfordshire. Prior to 2005, much of the bed comprised uniform silt, plus leaf-litter. Stands of reedmace Typha latifolia and other emergent vegetation were localised in less shaded areas. Initial survey results suggested a population at low abundance. A low-cost monitoring strategy was started in 2001 and continued three times a year to 2005, using engineering bricks, which offer artificial refuges. Crayfish are counted when bricks are lifted periodically. De-silting of c. 430 m river was carried out in February 2005, to improve habitat and to maintain the flood capacity in the channel upstream of a mill weir. Additional bricks were deployed a few weeks in advance of de-silting, then bricks and crayfish were lifted prior to dredging and were returned the next day. Starting upstream, soft, wet mud was dredged out, placed on the bank and searched manually for crayfish. Banks, tree roots and shallow margins were left undisturbed. In all, 4,142 crayfish were found in dredgings from a 430 m length of the mid channel. Crayfish were strongly associated with emergent vegetation, but many were present below the surface of the silt. Crayfish released in the dredged channel immediately burrowed into the silt retained on the channel margins. Monitoring after dredging showed no change in abundance in the main area with in-bank refuges and lots of bricks, but there was an increase in occupancy of bricks in an area where most crayfish had been in emergent vegetation.

Yersinia pestis endowed with increased cytotoxicity is avirulent in a bubonic plague model and induces rapid protection against pneumonic plague.

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Ayelet Zauberman

Full Text Available An important virulence strategy evolved by bacterial pathogens to overcome host defenses is the modulation of host cell death. Previous observations have indicated that Yersinia pestis, the causative agent of plague disease, exhibits restricted capacity to induce cell death in macrophages due to ineffective translocation of the type III secretion effector YopJ, as opposed to the readily translocated YopP, the YopJ homologue of the enteropathogen Yersinia enterocolitica Oratio8. This led us to suggest that reduced cytotoxic potency may allow pathogen propagation within a shielded niche, leading to increased virulence. To test the relationship between cytotoxic potential and virulence, we replaced Y. pestis YopJ with YopP. The YopP-expressing Y. pestis strain exhibited high cytotoxic activity against macrophages in vitro. Following subcutaneous infection, this strain had reduced ability to colonize internal organs, was unable to induce septicemia and exhibited at least a 10(7-fold reduction in virulence. Yet, upon intravenous or intranasal infection, it was still as virulent as the wild-type strain. The subcutaneous administration of the cytotoxic Y. pestis strain appears to activate a rapid and potent systemic, CTL-independent, immunoprotective response, allowing the organism to overcome simultaneous coinfection with 10,000 LD(50 of virulent Y. pestis. Moreover, three days after subcutaneous administration of this strain, animals were also protected against septicemic or primary pneumonic plague. Our findings indicate that an inverse relationship exists between the cytotoxic potential of Y. pestis and its virulence following subcutaneous infection. This appears to be associated with the ability of the engineered cytotoxic Y. pestis strain to induce very rapid, effective and long-lasting protection against bubonic and pneumonic plague. These observations have novel implications for the development of vaccines/therapies against Y. pestis and shed

Identification of exotic North American crayfish in Europe by DNA barcoding

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Filipová L.

2011-05-01

Full Text Available Several alien crayfish of North American origin have become established in Europe in recent decades, but their identification is often confusing. Our aim was to verify the taxonomic status of their European populations by DNA barcoding. We sequenced the cytochrome c oxidase subunit I (COI gene fragment of individuals representing all American crayfish known from European waters, and compared the results with reference sequences from North America. Our results confirm the morphological identification of Orconectes juvenilis from a population in eastern France, and of the marbled crayfish (Marmorkrebs, i.e., a parthenogenetic form of Procambarus fallax, from south-western Germany. Sequences of most individuals of presumed Procambarus acutus from the Netherlands were similar to American P. cf. acutus, but one was divergent, closer to a sequence of a reference individual of P. cf. zonangulus. However, divergences among three American P. cf. zonangulus samples were also high, comparable to interspecific variation within cambarid species complexes. The divergence between O. immunis from Europe and America also reached values corresponding to those observed among distinct Orconectes species. Genetic variation in the American range of these crayfish should therefore be further studied. Our study shows that DNA barcoding is useful for the rapid and accurate identification of exotic crayfish in Europe, and also provides insights into overall variation within these taxa.

Cadmium-binding proteins in midgut gland of freshwater crayfish Procambarus clarkii

Energy Technology Data Exchange (ETDEWEB)

Del Ramo, J.; Pastor, A.; Torreblanca, A.; Medina, J.; Diza-Mayans, J.

1989-02-01

Metallothioneins, metal binding proteins, were originally isolated and characterized by Margoshes and Vallee. These proteins have a high affinity for various heavy metals, particularly cadmium and mercury and have extensively been studied in mammals. Metal binding proteins have been observed in a variety of marine invertebrates; however, there is very little information available on metal binding proteins in freshwater invertebrates, and particularly in freshwater crustaceans. Cadmium is an ubiquitous non essential element which possesses high toxicity to aquatic organisms. Cadmium binding proteins observed in invertebrates have similar characteristics to mammalian metallothioneins. In 1978, the American red crayfish appeared in Albufera Lake and the surrounding rice fields (Valencia, Spain). Albufera Lake and the surrounding rice fields waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and wastewaters in this area. In previous reports the authors studied the toxicity and accumulation of cadmium on Procambarus clarkii of Albufera Lake. This crayfish shows a high resistance to cadmium and a great accumulation rate of this metal in several tissues, including midgut gland. Since Procambarus clarkii shows a high resistance to cadmium, the presence of cadmium binding proteins (Cd-BP) in midgut gland of these crayfish would be expected. This report describes results on the characterization of Cd-BPs obtained from cadmium exposed crayfish Procambarus clarkii, demonstrating their presence in this freshwater crayfish.

CRAYFISH PREDATION EXPERIMENTS ON THE INTRODUCED ZEBRA MUSSEL, DREISSENA POLYMORPHA, IN IRELAND, AND THEIR POTENTIAL FOR BIOCONTROL.

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REYNOLDS J. D.

2001-04-01

Full Text Available The zebra mussel Dreissena polymorpha, native to the Aralo-Caspian region, has spread across Europe in the last 180 years. Although it reached England in 1820, it only arrived in Ireland in around 1995, probably attached to the hull of pleasure boats, and since then has spread through the lowland Shannon and Erne systems, which are linked by canal. While White-clawed crayfish Austropotamobius pallipes (Lereboullet occur in these systems, Dreissena has not yet colonized sites with large crayfish populations. In laboratory experiments crayfish of both sexes ranging in size from 32-48 mm carapace length (CL were offered zebra mussels in 7 size classes spanning a range from 3-17 mm total length. Crayfish fed most on small mussels, although there was some correlation between size of crayfish and largest mussels attacked. When eaten mussels were not replaced, crayfish shifted to larger sizes. In the presence of alternative prey, experienced crayfish ate mussels and alternative foods in similar amounts while those who had never encountered zebra mussels nearly always chose the alternative foods first. The possibility of crayfish exerting significant controlling impacts on expanding mussel populations is discussed.

Phylogenetic species delimitation for crayfishes of the genus Pacifastacus.

Science.gov (United States)

Larson, Eric R; Castelin, Magalie; Williams, Bronwyn W; Olden, Julian D; Abbott, Cathryn L

2016-01-01

Molecular genetic approaches are playing an increasing role in conservation science by identifying biodiversity that may not be evident by morphology-based taxonomy and systematics. So-called cryptic species are particularly prevalent in freshwater environments, where isolation of dispersal-limited species, such as crayfishes, within dendritic river networks often gives rise to high intra- and inter-specific genetic divergence. We apply here a multi-gene molecular approach to investigate relationships among extant species of the crayfish genus Pacifastacus, representing the first comprehensive phylogenetic study of this taxonomic group. Importantly, Pacifastacus includes both the widely invasive signal crayfish Pacifastacus leniusculus, as well as several species of conservation concern like the Shasta crayfish Pacifastacus fortis. Our analysis used 83 individuals sampled across the four extant Pacifastacus species (omitting the extinct Pacifastacus nigrescens), representing the known taxonomic diversity and geographic distributions within this genus as comprehensively as possible. We reconstructed phylogenetic trees from mitochondrial (16S, COI) and nuclear genes (GAPDH), both separately and using a combined or concatenated dataset, and performed several species delimitation analyses (PTP, ABGD, GMYC) on the COI phylogeny to propose Primary Species Hypotheses (PSHs) within the genus. All phylogenies recovered the genus Pacifastacus as monophyletic, within which we identified a range of six to 21 PSHs; more abundant PSHs delimitations from GMYC and ABGD were always nested within PSHs delimited by the more conservative PTP method. Pacifastacus leniusculus included the majority of PSHs and was not monophyletic relative to the other Pacifastacus species considered. Several of these highly distinct P. leniusculus PSHs likely require urgent conservation attention. Our results identify research needs and conservation priorities for Pacifastacus crayfishes in western

Are Chinese consumers at risk due to exposure to metals in crayfish? A bioaccessibility-adjusted probabilistic risk assessment.

Science.gov (United States)

Peng, Qian; Nunes, Luís M; Greenfield, Ben K; Dang, Fei; Zhong, Huan

2016-03-01

Freshwater crayfish, the world's third largest crustacean species, has been reported to accumulate high levels of metals, while the current knowledge of potential risk associated with crayfish consumption lags behind that of finfish. We provide the first estimate of human health risk associated with crayfish (Procambarus clarkii) consumption in China, the world's largest producer and consumer of crayfish. We performed Monte Carlo Simulation on a standard risk model parameterized with local data on metal concentrations, bioaccessibility (φ), crayfish consumption rate, and consumer body mass. Bioaccessibility of metals in crayfish was found to be variable (68-95%) and metal-specific, suggesting a potential influence of metal bioaccessibility on effective metal intake. However, sensitivity analysis suggested risk of metals via crayfish consumption was predominantly explained by consumption rate (explaining >92% of total risk estimate variability), rather than metals concentration, bioaccessibility, or body mass. Mean metal concentrations (As, Cd, Cu, Ni, Pb, Se and Zn) in surveyed crayfish samples from 12 provinces in China conformed to national safety standards. However, risk calculation of φ-modified hazard quotient (HQ) and hazard index (HI) suggested that crayfish metals may pose a health risk for very high rate consumers, with a HI of over 24 for the highest rate consumers. Additionally, the φ-modified increased lifetime risk (ILTR) for carcinogenic effects due to the presence of As was above the acceptable level (10(-5)) for both the median (ILTR=2.5×10(-5)) and 90th percentile (ILTR=1.8×10(-4)), highlighting the relatively high risk of As in crayfish. Our results suggest a need to consider crayfish when assessing human dietary exposure to metals and associated health risks, especially for high crayfish-consuming populations, such as in China, USA and Sweden. Copyright © 2016 Elsevier Ltd. All rights reserved.

Partition of ruthenium-106 between the fresh water environment and crayfish

International Nuclear Information System (INIS)

Berg, G.G.; Ginsberg, E.

1976-01-01

Crayfish of two species, Orconectes obscurus and Cambarus robustus, were identified in West Valley, New York, in streams contaminated with radioactive wastes. 106 Ru accounted for over 90% of the gamma radioactivity in specimens collected in 1972, and had higher concentrations in the crayfish than in fish from that site. Crayfish are suggested as indicator organisms for 106 Ru. In subsequent aquarium experiments, crayfish exposed to water labeled with inorganic complexes of 106 Ru concentrated the dissolved ruthenium an average of 9 x and accumulated 50% of the equilibrium body burden in approximately 10 hr, with the bulk of the isotope bound at the surface of the exoskeleton. If food was also exposed to the labeled water, uptake was faster and high concentrations were found in the digestive gland, which showed concentration factors in excess of 25 x. Releases were slower and bimodal, with approximately 10% of body burden remaining after 1 or 2 months in repeated changes of water. Data describe the partition of 106 Ru to colloidal aggregates and organically-bound sediments, and its availability for bioconcentration. (author)

Accumulation of Heavy Metals in Crayfish and Fish from Selected Czech Reservoirs

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Iryna Kuklina

2014-01-01

Full Text Available To evaluate the accumulation of aluminium, cadmium, chromium, copper, lead, mercury, nickel, and zinc in crayfish and fish organ tissues, specimens from three drinking water reservoirs (Boskovice, Landštejn, and Nová Říše and one contaminated site (Darkovské moře in the Czech Republic were examined. Crayfish hepatopancreas was confirmed to be the primary accumulating site for the majority of metals (Cu > Zn > Ni > Cd > Cr, while Hg and Cr were concentrated in abdominal muscle, and Al and Pb were concentrated in gill. Metals found in Nová Říše specimens included Cu > Zn > Ni and those found in Boskovice included Zn > Hg > Cr. Cd concentrations were observed only in Landštejn specimens, while contaminated Darkovské moře specimens showed the highest levels of accumulation (Cu > Al > Zn > Pb. The majority of evaluated metals were found in higher concentrations in crayfish: Cu > Al > Zn > Ni > Cr > Cd > Pb, with Hg being the only metal accumulating higher in fish. Due to accumulation similarities of Al in crayfish and fish gill, differences of Hg in muscle, and features noted for the remaining metals in examined tissues, biomonitoring should incorporate both crayfish and fish to produce more relevant water quality surveys.

Toxicological studies of cadmium and zinc on the crayfish Orconectes virilis

International Nuclear Information System (INIS)

Mirenda, R.J.

1985-01-01

The acute toxicities of cadmium and of zinc to the crayfish Oronectes virilis were determined. Adult, intermolt crayfish were exposed to a series of concentrations of either cadmium or zinc for a two week period. Cadmium was found to be a cumulative poison to the crayfish; LC50 values decreased from 6.1 mg Cd/I for 96 hours to 0.7 mg Cd/I for two weeks. An incipient LC50 was also estimated to be 0.0604 mg Cd/I. Zinc was found to have a relatively low toxicity to O. virilis under the present exposure conditions. Whole animal and tissue analyses for cadmium or zinc were performed on the crayfish used in the acute toxicity tests. Whole animals concentrations both for cadmium and for zinc exhibited a linear relationship to exposure concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations of cadmium and zinc, and displayed a linear relationship to exposure concentrations (r = 0.82 and 0.87 respectively). The hepatopancreas displayed a plateau in metal concentrations and is probably the main storage site for both metals in the crayfish. The relationship of cadmium concentration to exposure concentration in the antennal glands also showed linearity (r = 0.65), while zinc levels reached a steady state level. All the remaining tissues analyzed exhibited a plateau in metal concentration

A Trial of Natural Habitat Enclosure Traps as a Sampling Tool for Juvenile Crayfish

OpenAIRE

Fjälling, Arne; Engdahl, Fredrik; Edsman, Lennart; Bohman, Patrik; Sandström, Alfred

2013-01-01

Recruitment is a vital factor in the assessment, management and population dynamics of decapods. Since the juvenile stages of crayfish often prefer heterogeneous habitats, sampling with quantitative and reproducible methods have so far been challenging. We evaluate a new quantitative sampling method for juvenile crayfish; the enclosure trap. A field test was carried out during two consecutive years on a population of signal crayfish, Pacifastacus leniusculus, in littoral areas of Swedish Lake...

Plague and the Human Flea, Tanzania

DEFF Research Database (Denmark)

Laudisoit, Anne; Leirs, Herwig; Makundi, Rhodes H

2007-01-01

Domestic fleas were collected in 12 villages in the western Usambara Mountains in Tanzania. Of these, 7 are considered villages with high plague frequency, where human plague was recorded during at least 6 of the 17 plague seasons between 1986 and 2004. In the remaining 5 villages with low plague...... frequency, plague was either rare or unrecorded. Pulex irritans, known as the human flea, was the predominant flea species (72.4%) in houses. The density of P. irritans, but not of other domestic fleas, was significantly higher in villages with a higher plague frequency or incidence. Moreover, the P....... irritans index was strongly positively correlated with plague frequency and with the logarithmically transformed plague incidence. These observations suggest that in Lushoto District human fleas may play a role in plague epidemiology. These findings are of immediate public health relevance because...

Diet of the crayfish Paranephrops zealandicus in bush and pasture streams : insights from stable isotopes and stomach analysis

International Nuclear Information System (INIS)

Hollows, J.W.; Townsend, C.R.; Collier, K.J.

2002-01-01

Crayfish (Paranephrops zealandicus White) stomachs from streams in both native bush (mainly tree leaves and dicotyledonous seeds) and exotic pasture settings (mainly grass stems and monocotyledonous seeds) were dominated by allochthonous material. More detritus occurred in stomachs in autumn-winter than in spring-summer, but quantities were similar in crayfish from native bush and pasture streams. The stomachs of larger crayfish contained a significantly greater proportion of detritus than smaller individuals. Aquatic invertebrates were the second most abundant dietary category by volume, with highest values in winter, but there were no significant differences between land uses or crayfish size classes. A wide range of invertebrates was eaten by crayfish, with mayfly nymphs, chironomid larvae, and snails predominating. The latter were numerically more prominent in crayfish from bush than pasture streams. Terrestrial invertebrates were recorded from 4% of stomachs, but there were no significant differences in relation to land use, season, or crayfish size class. Despite aquatic invertebrates making up 13 C and perhaps of microfloral origin, seems to be an important energy source for crayfish in both stream types. (author). 52 refs., 5 figs., 2 tabs

[Plague in Zaire].

Science.gov (United States)

Janssens, P G; Pattyn, S R

1994-01-01

Two endemic foci of plague have been discovered in Zaïre, the first in the Ituri in 1928, the other in North-Kivu in 1938. They are situated in the region of the great East-African Rift and are adjacent to the Ugandan focus, identified in 1877. A strict surveillance of these endemic foci makes it possible to state that, between 1928 and 1959, 632 cases of plague have been diagnosed in the Ituri, or 20 a year, and 190 in the N-Kivu, or 8 a year. Since then several flare ups have been notified. This situation is very remote from the "black death" concept. Yersinia pestis presents, besides its bipolar staining, many other characteristics such as the indispensable presence of iron to produce virulence, or the fermentation of glycerine and reduction of nitrates as parameters for the identification of 3 biovars, corresponding with a specific geographic distribution: antiqua, medievalis, orientalis or maritima. The antigenic structure has been discussed and also the role of plasmids. Plague is a disease of rats, a variegated gathering of rodents with different degrees of tolerance and sensitiveness to Y.pestis, living in a frail equilibrium. The multimammate houserat was in the Ituri the principal agent until the black rat Rattus rattus invaded the region and a new balance came into being. The frequent changes in taxonomy of Mastomys caused uncertainties. The transmission is due to fleas subject to a blocking of their ventriculum by Y.pestis. Fleas play an active part in the process. Man is only a casual intruder. The pathogenicity is related to its invasiveness and its intracellular localization in macrophages and other R.E. cells, in which Y.pestis can survive. The bubo is characteristic of the disease. In Zaïre a septicaemic tendency has been observed, with a possible involvement of the C.N.S. and of the lungs. The latter may produce among the surrounding relatives primary pneumonic plague. The clinical diagnosis ought to be confirmed by bacteriologic investigation

Enzymatic production of N-acetyl-d-glucosamine from crayfish shell wastes pretreated via high pressure homogenization.

Science.gov (United States)

Wei, Guoguang; Zhang, Alei; Chen, Kequan; Ouyang, Pingkai

2017-09-01

This study presents an efficient pretreatment of crayfish shell using high pressure homogenization that enables N-acetyl-d-glucosamine (GlcNAc) production by chitinase. Firstly, the chitinase from Serratia proteamaculans NJ303 was screened for its ability to degrade crayfish shell and produce GlcNAc as the sole product. Secondly, high pressure homogenization, which caused the crayfish shell to adopt a fluffy netted structure that was characterized by Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), was evaluated as the best pretreatment method. In addition, the optimal conditions of high pressure homogenization of crayfish shell were determined to be five cycles at a pressure of 400bar, which achieved a yield of 3.9g/L of GlcNAc from 25g/L of crayfish shell in a batch enzymatic reaction over 1.5h. The results showed high pressure homogenization might be an efficient method for direct utilization of crayfish shell for enzymatic production of GlcNAc. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transmission efficiency of the plague pathogen (Y. pestis) by the flea, Xenopsylla skrjabini, to mice and great gerbils.

Science.gov (United States)

Zhang, Yujiang; Dai, Xiang; Wang, Qiguo; Chen, Hongjian; Meng, Weiwei; Wu, Kemei; Luo, Tao; Wang, Xinhui; Rehemu, Azhati; Guo, Rong; Yu, Xiaotao; Yang, Ruifu; Cao, Hanli; Song, Yajun

2015-05-01

Plague, a zoonotic disease caused by Yersinia pestis, is characterized by its ability to persist in the plague natural foci. Junggar Basin plague focus was recently identified in China, with Rhombomys opimus (great gerbils) and Xenopsylla skrjabini as the main reservoir and vector for plague. No transmission efficiency data of X. skrjabini for Y. pestis is available till now. In this study, we estimated the median infectious dose (ID50) and the blockage rates of X. skrjabini with Y. pestis, by using artificial feeders. We then evaluated the flea transmission ability of Y. pestis to the mice and great gerbils via artificial bloodmeal feeding. Finally, we investigated the transmission of Y. pestis to mice with fleas fed by infected great gerbils. ID50 of Y. pestis to X. skrjabini was estimated as 2.04 × 10(5) CFU (95% CI, 1.45 × 10(5) - 3.18 × 10(5) CFU), around 40 times higher than that of X. cheopis. Although fleas fed by higher bacteremia bloodmeal had higher infection rates for Y. pestis, they lived significantly shorter than their counterparts. X. skrjabini could get fully blocked as early as day 3 post of infection (7.1%, 3/42 fleas), and the overall blockage rate of X. cheopis was estimated as 14.9% (82/550 fleas) during the 14 days of investigation. For the fleas infected by artificial feeders, they seemed to transmit plague more efficiently to great gerbils than mice. Our single flea transmission experiments also revealed that, the transmission capacity of naturally infected fleas (fed by infected great gerbils) was significantly higher than that of artificially infected ones (fed by artificial feeders). Our results indicated that ID50 of Y. pestis to X. skrjabini was higher than other fleas like X. cheopis, and its transmission efficiency to mice might be lower than other flea vectors in the artificial feeding modes. We also found different transmission potentials in the artificially infected fleas and the naturally infected ones. Further studies are

Effects of Different Social and Environmental Conditions on Established Dominance Relationships in Crayfish.

Science.gov (United States)

Herberholz, Jens; Swierzbinski, Matthew E; Birke, Juliane M

2016-04-01

Like most social animals, crayfish readily form dominance relationships and linear social hierarchies when competing for limited resources. Competition often entails dyadic aggressive interactions, from which one animal emerges as the dominant and one as the subordinate. Once dominance relationships are formed, they typically remain stable for extended periods of time; thus, access to future resources is divided unequally among conspecifics. We previously showed that firmly established dominance relationships in juvenile crayfish can be disrupted by briefly adding a larger conspecific to the original pair. This finding suggested that the stability of social relationships in crayfish was highly context-dependent and more transient than previously assumed. We now report results that further identify the mechanisms underlying the destabilization of crayfish dominance relationships. We found that rank orders remained stable when conspecifics of smaller or equal size were added to the original pair, suggesting that both dominant and subordinate must be defeated by a larger crayfish in order to destabilize dominance relationships. We also found that dominance relationships remained stable when both members of the original pair were defeated by larger conspecifics in the absence of their original opponent. This showed that dominance relationships are not destabilized unless both animals experience defeat together. Lastly, we found that dominance relationships of pairs were successfully disrupted by larger intruders, although with reduced magnitude, after all chemical cues associated with earlier agonistic experiences were eliminated. These findings provide important new insights into the contextual features that regulate the stability of social dominance relationships in crayfish and probably in other species as well. © 2016 Marine Biological Laboratory.

Determination of lead in treated crayfish Procambarus clarkii: accumulation in different tissues

Energy Technology Data Exchange (ETDEWEB)

Pastor, A.; Medina, J.; Del Ramo, J.; Torreblanca, A.; Diaz-Mayans, J.; Hernandez, F.

1988-09-01

The continual loading of trace metals into our environment represents a water pollution problem due to their toxic effects on aquatic biota. In addition, metal ions can be incorporated into food chains and concentrated by aquatic organisms to a level that affects their physiological state. There are several investigations on the toxic effects and bioaccumulation of lead in fishes, molluscs, and crustaceans. Lake Albufera (Valencia, Spain) and the surrounding rice-field waters are subjected to large loads of sewage and toxic industrial residues (including heavy metals) from many urban wastewaters in the area. In 1978, the American red crayfish Procambarus clarkii (Girard) appeared in Lake Albufera. The crayfish have reached a high density producing ecological and agricultural economic problems in rice crops. The crayfish is being fished commercially for human consumption without adequate protection to human health. The purpose of the present study was to investigate the accumulation of lead in tissues of the crayfish P. clarkii following short term lead exposure at several sublethal concentrations. The gills, midgut glands, antennal glands and muscle were analyzed by atomic absorption spectrophotometry.

Plague: Clinics, Diagnosis and Treatment.

Science.gov (United States)

Nikiforov, Vladimir V; Gao, He; Zhou, Lei; Anisimov, Andrey

2016-01-01

Plague still poses a significant threat to human health and as a reemerging infection is unfamiliar to the majority of the modern medical doctors. In this chapter, the plague is described according to Dr. Nikiforov's experiences in the diagnosis and treatment of patients, and also a review of the relevant literature on this subject is provided. The main modern methods and criteria for laboratory diagnosis of plague are briefly described. The clinical presentations include the bubonic and pneumonic form, septicemia, rarely pharyngitis, and meningitis. Early diagnosis and the prompt initiation of treatment reduce the mortality rate associated with bubonic plague and septicemic plague to 5-50 %; although a delay of more than 24 h in the administration of antibiotics and antishock treatment can be fatal for plague patients. Most human cases can successfully be treated with antibiotics.

A comprehensive study on the role of the Yersinia pestis virulence markers in an animal model of pneumonic plague

NARCIS (Netherlands)

Kaman, W.E.; Hawkey, S.; van der Kleij, D.; Broekhuijsen, M.P.; Silman, N.J.; Bikker, F.J.

2011-01-01

Yersinia pestis, the Gram-negative bacterial agent of plague, is a zoonotic pathogen that primarily infects wild rodents and is transmitted by fleas. Y. pestis is one of the most invasive and virulent bacterial pathogens and has caused devastating pandemics, including the Black Death of 14th century

Sylvatic plague vaccine: combating plague in prarie dogs and black-footed ferrets

Science.gov (United States)

Rocke, Tonie E.; Abbott, Rachel C.

2012-01-01

After achieving promising results in laboratory trials, researchers at the USGS National Wildlife Health Center (NWHC) and University of Wisconsin at Madison will soon begin field testing a new oral vaccine for sylvatic plague, a devastating disease affecting prairie dogs and other mammals, particularly the endangered black-footed ferret. Our team has developed and is currently registering a sylvatic plague vaccine (SPV) that uses raccoon poxvirus (RCN) to express two key antigens of the Yersinia pestis bacterium, the causative agent of plague.

Human plague occurrences in Africa

DEFF Research Database (Denmark)

Neerinckx, Simon; Bertherat, Eric; Leirs, Herwig

2010-01-01

Plague remains a public health concern worldwide, but particularly in Africa. Despite the long-standing history of human plague, it is difficult to get a historical and recent overview of the general situation. We searched and screened available information sources on human plague occurrences in ...

Plague and Climate: Scales Matter

Science.gov (United States)

Ben Ari, Tamara; Neerinckx, Simon; Gage, Kenneth L.; Kreppel, Katharina; Laudisoit, Anne; Leirs, Herwig; Stenseth, Nils Chr.

2011-01-01

Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts) of the plague system and is a likely factor to explain some of plague's variability from small and regional to large scales. Here, we review effects of climate variables on plague hosts and vectors from individual or population scales to studies on the whole plague system at a large scale. Upscaled versions of small-scale processes are often invoked to explain plague variability in time and space at larger scales, presumably because similar scale-independent mechanisms underlie these relationships. This linearity assumption is discussed in the light of recent research that suggests some of its limitations. PMID:21949648

Spatial dynamics of the noble crayfish (Astacus astacus, L. in the Paklenica National Park

Directory of Open Access Journals (Sweden)

G.I.V. Klobucar

2008-07-01

Full Text Available The aim of this work was to analyse the spatial dynamics of a noble crayfish population inhabiting the Velika Paklenica Stream (Paklenica National Park, Croatia. The study was conducted in July 2000, and between March and September 2002. Crayfish were trapped by baited LiNi traps and hand-made traps at two localities over 25 nights. We recorded the precise position of the captured crayfish, their sex, and total length. Crayfish were individually marked and then released back into the stream at the same spot where they were caught. Spatial analyses included determination of movement direction, distribution type, home range, total distance travelled, and mean daily movement. A mean home range of approximately 19 m was calculated. No difference in home range between the sexes was found. There was a large individual variation in the extent of movement without any effect of sex or size.

Cadmium accumulation in the crayfish, Procambarus clarkii, using graphite furnace atomic absorption spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Diaz-Mayans, J.; Hernandez, F.; Medina, J.; Del Ramo, J.; Torreblanca, A.

1986-11-01

Lake Albufera and the surrounding rice-field waters are being subject to very heavy loads of sewage and toxic industrial residues (including heavy metals and pesticides) from the many urban and wastewaters in this area. The American red crayfish Procambarus clarkii is native to the Louisiana marshes (USA). In 1978, the crayfish appeared in Lake Albufera near Valencia (Spain), and presently, without adequate sanitary controls, the crayfish is being fished commercially for human consumption. In view of this interest, it is important to have accurate information on concentrations of cadmium in natural waters and cadmium levels of tissues of freshwaters animals used as human food, as well as the accumulation rates of this metal in this animal. In the present study, the authors investigated the accumulation of cadmium in several tissues of the red crayfish, P clarkii (Girard) from Lake Albufera following cadmium exposure. Determinations of cadmium were made by flameless atomic absorption spectroscopy and the standard additions method. Digestion of samples was made by wet ashing in open flasks with concentrated HNO/sub 3/ at 80-90/sup 0/C.

Plague Diagnosis and Treatment

Science.gov (United States)

... Search Form Controls Cancel Submit Search the CDC Plague Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . Plague Home Ecology & Transmission Symptoms Diagnosis & Treatment Maps & Statistics ...

Effects of historical lead–zinc mining on riffle-dwelling benthic fish and crayfish in the Big River of southeastern Missouri, USA

Science.gov (United States)

Allert, A.L.; DiStefano, R.J.; Fairchild, J.F.; Schmitt, C.J.; McKee, M.J.; Girondo, J.A.; Brumbaugh, W.G.; May, T.W.

2013-01-01

The Big River (BGR) drains much of the Old Lead Belt mining district (OLB) in southeastern Missouri, USA, which was historically among the largest producers of lead–zinc (Pb–Zn) ore in the world. We sampled benthic fish and crayfish in riffle habitats at eight sites in the BGR and conducted 56-day in situ exposures to the woodland crayfish (Orconectes hylas) and golden crayfish (Orconectes luteus) in cages at four sites affected to differing degrees by mining. Densities of fish and crayfish, physical habitat and water quality, and the survival and growth of caged crayfish were examined at sites with no known upstream mining activities (i.e., reference sites) and at sites downstream of mining areas (i.e., mining and downstream sites). Lead, zinc, and cadmium were analyzed in surface and pore water, sediment, detritus, fish, crayfish, and other benthic macro-invertebrates. Metals concentrations in all materials analyzed were greater at mining and downstream sites than at reference sites. Ten species of fish and four species of crayfish were collected. Fish and crayfish densities were significantly greater at reference than mining or downstream sites, and densities were greater at downstream than mining sites. Survival of caged crayfish was significantly lower at mining sites than reference sites; downstream sites were not tested. Chronic toxic-unit scores and sediment probable effects quotients indicated significant risk of toxicity to fish and crayfish, and metals concentrations in crayfish were sufficiently high to represent a risk to wildlife at mining and downstream sites. Collectively, the results provided direct evidence that metals associated with historical mining activities in the OLB continue to affect aquatic life in the BGR.

First record of the invasive Australian redclaw crayfish Cherax quadricarinatus (von Martens, 1868 in the Crocodile River, Kruger National Park, South Africa

Directory of Open Access Journals (Sweden)

Robin M. Petersen

2017-03-01

Full Text Available The redclaw crayfish Cherax quadricarinatus (von Martens, 1868, a robust freshwater crayfish native to Australia and Papua New Guinea, has now been recorded from the Kruger National Park (KNP. Previously absent from the Crocodile River, SAN Parks received a report in February 2016 of redclaw crayfish below the Van Graan Dam on the border of the KNP. Here, we provide evidence of the presence of redclaw crayfish in the Crocodile River. A better understanding of the redclaw crayfish distribution, habitat preferences, rate of spread and impacts on the local aquatic ecosystems in the Crocodile River is urgently required to develop mitigation strategies that minimise the spread of this invasive crayfish in the KNP and the Komati Catchment. The negative impacts of global crayfish introductions justify efforts to discourage further introductions and prevent their secondary spread. Conservation implications: A better understanding of the redclaw crayfish distribution, habitat preferences, rate of spread and impacts on the local aquatic ecosystems in the Crocodile River is urgently required to develop mitigation strategies that minimise the spread of this invasive crayfish in the Kruger National Park and the Komati Catchment.

Distribution of crayfish species in Hungarian waters

NARCIS (Netherlands)

Mercédesz, Ludányi; Peeters, E.T.H.M.; Kiss, B.; Roessink, I.

2016-01-01

Three native crayfish species, i.e.~Astacus astacus, Astacus leptodactylus and Austropotamobius torrentium, occur in Hungary. Lately, however, non-indigenous crustaceans have also invaded the country Their most recent distribution and impact on the occurrences of the native species is not clear.

Modeling the epidemiological history of plague in Central Asia: Palaeoclimatic forcing on a disease system over the past millennium

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Kausrud Kyrre

2010-08-01

Full Text Available Abstract Background Human cases of plague (Yersinia pestis infection originate, ultimately, in the bacterium's wildlife host populations. The epidemiological dynamics of the wildlife reservoir therefore determine the abundance, distribution and evolution of the pathogen, which in turn shape the frequency, distribution and virulence of human cases. Earlier studies have shown clear evidence of climatic forcing on contemporary plague abundance in rodents and humans. Results We find that high-resolution palaeoclimatic indices correlate with plague prevalence and population density in a major plague host species, the great gerbil (Rhombomys opimus, over 1949-1995. Climate-driven models trained on these data predict independent data on human plague cases in early 20th-century Kazakhstan from 1904-1948, suggesting a consistent impact of climate on large-scale wildlife reservoir dynamics influencing human epidemics. Extending the models further back in time, we also find correspondence between their predictions and qualitative records of plague epidemics over the past 1500 years. Conclusions Central Asian climate fluctuations appear to have had significant influences on regional human plague frequency in the first part of the 20th century, and probably over the past 1500 years. This first attempt at ecoepidemiological reconstruction of historical disease activity may shed some light on how long-term plague epidemiology interacts with human activity. As plague activity in Central Asia seems to have followed climate fluctuations over the past centuries, we may expect global warming to have an impact upon future plague epidemiology, probably sustaining or increasing plague activity in the region, at least in the rodent reservoirs, in the coming decades. See commentary: http://www.biomedcentral.com/1741-7007/8/108

A comparison of two gears for quantifying abundance of lotic-dwelling crayfish

Science.gov (United States)

Williams, Kristi; Brewer, Shannon K.; Ellersieck, Mark R.

2014-01-01

Crayfish (saddlebacked crayfish, Orconectes medius) catch was compared using a kick seine applied two different ways with a 1-m2 quadrat sampler (with known efficiency and bias in riffles) from three small streams in the Missouri Ozarks. Triplicate samples (one of each technique) were taken from two creeks and one headwater stream (n=69 sites) over a two-year period. General linear mixed models showed the number of crayfish collected using the quadrat sampler was greater than the number collected using either of the two seine techniques. However, there was no significant interaction with gear suggesting year, stream size, and channel unit type did not relate to different catches of crayfish by gear type. Variation in catch among gears was similar, as was the proportion of young-of-year individuals across samples taken with different gears or techniques. Negative binomial linear regression provided the appropriate relation between the gears which allows correction factors to be applied, if necessary, to relate catches by the kick seine to those of the quadrat sampler. The kick seine appears to be a reasonable substitute to the quadrat sampler in these shallow streams, with the advantage of ease of use and shorter time required per sample.

Duck plague

Science.gov (United States)

Friend, M.

1999-01-01

Duck plague is caused by a herpesvirus. Infection often results in an acute, contagious, and fatal disease. As with many other herpesviruses, duck plague virus can establish inapparent infections in birds that survive exposure to it, a state referred to as latency. During latency, the virus cannot be detected by standard methods for virus isolation. Studies of domestic species of waterfowl have detected multiple strains of the virus that vary in their ability to cause disease and death. Little is known about the response of wild waterfowl to strain differences.Duck plague outbreaks are thought to be caused when birds that carry the virus shed it through fecal or oral discharge, thus releasing the virus into food and water with which susceptible birds may have contact. Experimental studies have demonstrated spontaneous virus shedding by duck plague carriers during spring. Changes in the duration of daylight and onset of breeding are thought to be physiological stresses that stimulate virus shedding at this time of year. The carriers are immune to the disease, but the virus shed by them causes infection and disease among susceptible waterfowl. Bird-to-bird contact and contact with virus that has contaminated the environment perpetuate an outbreak. Scavenging and decomposition of carcasses of infected birds also contaminate the environment by releasing viruses from tissues and body fluids. Virus transmission through the egg has been reported, but the role of the egg in the disease cycle remains to be resolved.

Comparing macrophyte herbivory by introduced Louisiana crayfish ...

African Journals Online (AJOL)

The omnivorous Louisiana crayfish, Procambarus clarkii, has caused significant changes to macrophyte communities worldwide and may have similar negative effects in Kenya if used as a biological control agent for snails harbouring human schistosomes. Here we examine how herbivory by the introduced Louisiana ...

Water chemistry and endangered white-clawed Crayfish: a literature review and field study of water chemistry association in Austropotamobius pallipes

Directory of Open Access Journals (Sweden)

Haddaway N.R.

2015-01-01

Full Text Available Populations of the endangered white-clawed crayfish (Austropotamobius pallipes have rapidly declined in distribution and density in recent decades as a result of invasive crayfish, disease and habitat degradation. The species is thought to be particularly sensitive to water chemistry, and has been proposed as a bio-indicator of water quality. Here we detail the results of a systematic review of the literature regarding the chemistry of waterbodies inhabited by white-clawed crayfish, along with a wide-scale field study of the chemistry of crayfish-inhabited waterbodies in the UK. We use these data to examine potentially significant variables influencing crayfish distribution. Several variables appear to have thresholds that affect crayfish distribution; crayfish presence was associated with high dissolved oxygen, low conductivity, ammonium, sodium, and phosphate, and to a lesser extent low sulphate, nitrate, and total suspended solids. Some variables (magnesium, potassium, sodium, sulphate, nitrate, and total suspended solids may be tolerated at moderate to high concentrations in isolation (indicated by the presence of some populations in high levels of these variables, but suites of chemical conditions may act synergistically in situ and must be considered together. Recent efforts to conserve white-clawed crayfish have included relocations to Ark Sites; novel protected habitats with reduced risk of the introduction of disease, invasive crayfish and habitat degradation. We use our findings to propose the first detailed guidelines for common water chemistry variables of potential Ark Sites for the conservation of the species throughout its European range.

Crayfish impact desert river ecosystem function and litter-dwelling invertebrate communities through association with novel detrital resources.

Directory of Open Access Journals (Sweden)

Eric K Moody

Full Text Available Shifts in plant species distributions due to global change are increasing the availability of novel resources in a variety of ecosystems worldwide. In semiarid riparian areas, hydric pioneer tree species are being replaced by drought-tolerant plant species as water availability decreases. Additionally, introduced omnivorous crayfish, which feed upon primary producers, allochthonous detritus, and benthic invertebrates, can impact communities at multiple levels through both direct and indirect effects mediated by drought-tolerant plants. We tested the impact of both virile crayfish (Orconectes virilis and litter type on benthic invertebrates and the effect of crayfish on detrital resources across a gradient of riparian vegetation drought-tolerance using field cages with leaf litter bags in the San Pedro River in Southeastern Arizona. Virile crayfish increased breakdown rate of novel drought-tolerant saltcedar (Tamarix ramosissima, but did not impact breakdown of drought-tolerant seepwillow (Baccharis salicifolia or hydric Fremont cottonwood (Populus fremontii and Gooding's willow (Salix goodingii. Effects on invertebrate diversity were observed at the litter bag scale, but no effects were found at the cage scale. Crayfish decreased alpha diversity of colonizing macroinvertebrates, but did not affect beta diversity. In contrast, the drought-tolerant litter treatment decreased beta diversity relative to hydric litter. As drought-tolerant species become more abundant in riparian zones, their litter will become a larger component of the organic matter budget of desert streams which may serve to homogenize the litter-dwelling community and support elevated populations of virile crayfish. Through impacts at multiple trophic levels, crayfish have a significant effect on desert stream ecosystems.

Historical Y. pestis Genomes Reveal the European Black Death as the Source of Ancient and Modern Plague Pandemics.

Science.gov (United States)

Spyrou, Maria A; Tukhbatova, Rezeda I; Feldman, Michal; Drath, Joanna; Kacki, Sacha; Beltrán de Heredia, Julia; Arnold, Susanne; Sitdikov, Airat G; Castex, Dominique; Wahl, Joachim; Gazimzyanov, Ilgizar R; Nurgaliev, Danis K; Herbig, Alexander; Bos, Kirsten I; Krause, Johannes

2016-06-08

Ancient DNA analysis has revealed an involvement of the bacterial pathogen Yersinia pestis in several historical pandemics, including the second plague pandemic (Europe, mid-14(th) century Black Death until the mid-18(th) century AD). Here we present reconstructed Y. pestis genomes from plague victims of the Black Death and two subsequent historical outbreaks spanning Europe and its vicinity, namely Barcelona, Spain (1300-1420 cal AD), Bolgar City, Russia (1362-1400 AD), and Ellwangen, Germany (1485-1627 cal AD). Our results provide support for (1) a single entry of Y. pestis in Europe during the Black Death, (2) a wave of plague that traveled toward Asia to later become the source population for contemporary worldwide epidemics, and (3) the presence of an historical European plague focus involved in post-Black Death outbreaks that is now likely extinct. Copyright © 2016 Elsevier Inc. All rights reserved.

Range extensions of three crayfishes (Faxonius yanahlindus, F. placidus, and F. erichsonianus) into Mississippi

Science.gov (United States)

Susan B. Adams; Robert L. Jones

2018-01-01

We report 3 new state crayfish records from the Tennessee River drainage in Tishomingo County, Mississippi: 1 is a re-identification of previously published material, and 2 are from unpublished collections. Faxonius yanahlindus (Spinywrist Crayfish), recently described from the middle Tennessee River drainage in northwest Alabama and southern...

Protect Yourself from Plague

Science.gov (United States)

... rodents. Plague can also infect humans and their pets. How do people get plague? • • Bites of infected fleas • • Touching or ... be treated successfully with antibiotics, but an infected person must be treated ... your pets 1. Eliminate nesting places for rodents around homes, ...

Nutritional treatment of cancer cachexia in rats. Use of a diet formulated with a crayfish enzymatic extract.

Science.gov (United States)

Cremades, Olga; Parrado, Juan; Jover, María; Collantes de Terán, Laura; Gutiérrez, Juan Francisco; Bautista Palomas, Juan D

2007-09-01

Terminal cancer-associated cachexia, characterized by a marked weight loss, anorexia, asthenia and anemia, is usually associated with a malnutrition status. To investigate whether a diet formulated with a crayfish enzymatic extract, enriched in essential amino acids, omega-3 fatty acids, and astaxanthin, would be effective for the treatment of cancer-associated cachexias, by decreasing mortality and morbidity rates in cachectic rats and/or improving survival. Two types of diet were used: a standard diet and one formulated with crayfish enzymatic extract. Rats were divided into two groups (24 animals per group): one without tumor (T-) and the other with tumor (T+) (AH-130 Yoshida ascites hepatoma). Each group was further divided into two subgroups (12 animals per subgroup). Two subgroups (T-(standard) and T+(standard)) were fed the standard diet and the other two (T-(CFEE) and T+(CFEE)) the crayfish enzymatic extract one for four weeks, after which different tissue and plasma parameters were studied. The implantation of the tumor resulted in a considerable loss of muscle and adipose tissue mass in both groups, but the loss of muscle and fat was lower in the group fed the crayfish enzymatic extract diet. There was also a concomitant increase in the plasma concentration of TNF-alpha, although the increase was smaller in the crayfish enzymatic extract-treated group. This study shows that although the treatment of cachetic rats with the crayfish enzymatic extract diet did not revert the cachexia, it increased survival (57.1% vs. 25.9% in the group treated with crayfish enzymatic extract and standard diets, respectively) and meliorated the cachexia symptoms--anorexia and body mass loss (muscle and adipose tissue).

Bioaccumulation of lead nitrate in freshwater crayfish (Astacus leptodactylus) tissues under aquaculture conditions.

Science.gov (United States)

Naghshbandi, N; Zare, S; Heidari, R; Soleimani Palcheglu, S

2007-09-15

The aim of this research was to evaluate the amount of lead in the tissue of Astacus leptodactylus especially in their muscle which the consumed part of their body. In this study the crayfish was exposed to intermediate concentration of lead nitrate (500 microg L(-1)) for periods up to 3 weeks. In the first, second and third weeks bioaccumulation in various tissues was under investigation. The data of toxicological analysis obtained by the method of atomic absorption revealed that the levels of bioaccumulation of metal are different in various tissues of this crayfish. The accumulation of the lead in gills was the highest and in muscles was lowest degree. The amount of heavy metals in the tissues of crayfish was as follow. Gills>exoskeleton>hepatopancreas (digestive glands)>digestive tract>green gland>testis and ovary>muscles.

Mechanism study on a plague outbreak driven by the construction of a large reservoir in southwest china (surveillance from 2000-2015.

Directory of Open Access Journals (Sweden)

Xin Wang

2017-03-01

Full Text Available Plague, a Yersinia pestis infection, is a fatal disease with tremendous transmission capacity. However, the mechanism of how the pathogen stays in a reservoir, circulates and then re-emerges is an enigma.We studied a plague outbreak caused by the construction of a large reservoir in southwest China followed 16-years' surveillance.The results show the prevalence of plague within the natural plague focus is closely related to the stability of local ecology. Before and during the decade of construction the reservoir on the Nanpan River, no confirmed plague has ever emerged. With the impoundment of reservoir and destruction of drowned farmland and vegetation, the infected rodent population previously dispersed was concentrated together in a flood-free area and turned a rest focus alive. Human plague broke out after the enzootic plague via the flea bite. With the construction completed and ecology gradually of human residential environment, animal population and type of vegetation settling down to a new balance, the natural plague foci returned to a rest period. With the rodent density decreased as some of them died, the flea density increased as the rodents lived near or in local farm houses where had more domestic animals, and human has a more concentrated population. In contrast, in the Himalayan marmot foci of the Qinghai-Tibet Plateau in the Qilian Mountains. There are few human inhabitants and the local ecology is relatively stable; plague is prevalence, showing no rest period. Thus the plague can be significantly affected by ecological shifts.

Mechanism study on a plague outbreak driven by the construction of a large reservoir in southwest china (surveillance from 2000-2015).

Science.gov (United States)

Wang, Xin; Wei, Xiaoyu; Song, Zhizhong; Wang, Mingliu; Xi, Jinxiao; Liang, Junrong; Liang, Yun; Duan, Ran; Tian, Kecheng; Zhao, Yong; Tang, Guangpeng; You, Lv; Yang, Guirong; Liu, Xuebin; Chen, Yuhuang; Zeng, Jun; Wu, Shengrong; Luo, Shoujun; Qin, Gang; Hao, Huijing; Jing, Huaiqi

2017-03-01

Plague, a Yersinia pestis infection, is a fatal disease with tremendous transmission capacity. However, the mechanism of how the pathogen stays in a reservoir, circulates and then re-emerges is an enigma. We studied a plague outbreak caused by the construction of a large reservoir in southwest China followed 16-years' surveillance. The results show the prevalence of plague within the natural plague focus is closely related to the stability of local ecology. Before and during the decade of construction the reservoir on the Nanpan River, no confirmed plague has ever emerged. With the impoundment of reservoir and destruction of drowned farmland and vegetation, the infected rodent population previously dispersed was concentrated together in a flood-free area and turned a rest focus alive. Human plague broke out after the enzootic plague via the flea bite. With the construction completed and ecology gradually of human residential environment, animal population and type of vegetation settling down to a new balance, the natural plague foci returned to a rest period. With the rodent density decreased as some of them died, the flea density increased as the rodents lived near or in local farm houses where had more domestic animals, and human has a more concentrated population. In contrast, in the Himalayan marmot foci of the Qinghai-Tibet Plateau in the Qilian Mountains. There are few human inhabitants and the local ecology is relatively stable; plague is prevalence, showing no rest period. Thus the plague can be significantly affected by ecological shifts.

Predatory functional response and prey choice identify predation differences between native/invasive and parasitised/unparasitised crayfish.

Science.gov (United States)

Haddaway, Neal R; Wilcox, Ruth H; Heptonstall, Rachael E A; Griffiths, Hannah M; Mortimer, Robert J G; Christmas, Martin; Dunn, Alison M

2012-01-01

Invasive predators may change the structure of invaded communities through predation and competition with native species. In Europe, the invasive signal crayfish Pacifastacus leniusculus is excluding the native white clawed crayfish Austropotamobius pallipes. This study compared the predatory functional responses and prey choice of native and invasive crayfish and measured impacts of parasitism on the predatory strength of the native species. Invasive crayfish showed a higher (>10%) prey (Gammarus pulex) intake rate than (size matched) natives, reflecting a shorter (16%) prey handling time. The native crayfish also showed greater selection for crustacean prey over molluscs and bloodworm, whereas the invasive species was a more generalist predator. A. pallipes parasitised by the microsporidian parasite Thelohania contejeani showed a 30% reduction in prey intake. We suggest that this results from parasite-induced muscle damage, and this is supported by a reduced (38%) attack rate and increased (30%) prey handling time. Our results indicate that the per capita (i.e., functional response) difference between the species may contribute to success of the invader and extinction of the native species, as well as decreased biodiversity and biomass in invaded rivers. In addition, the reduced predatory strength of parasitized natives may impair their competitive abilities, facilitating exclusion by the invader.

Early emergence of Yersinia pestis as a severe respiratory pathogen.

Science.gov (United States)

Zimbler, Daniel L; Schroeder, Jay A; Eddy, Justin L; Lathem, Wyndham W

2015-06-30

Yersinia pestis causes the fatal respiratory disease pneumonic plague. Y. pestis recently evolved from the gastrointestinal pathogen Y. pseudotuberculosis; however, it is not known at what point Y. pestis gained the ability to induce a fulminant pneumonia. Here we show that the acquisition of a single gene encoding the protease Pla was sufficient for the most ancestral, deeply rooted strains of Y. pestis to cause pneumonic plague, indicating that Y. pestis was primed to infect the lungs at a very early stage in its evolution. As Y. pestis further evolved, modern strains acquired a single amino-acid modification within Pla that optimizes protease activity. While this modification is unnecessary to cause pneumonic plague, the substitution is instead needed to efficiently induce the invasive infection associated with bubonic plague. These findings indicate that Y. pestis was capable of causing pneumonic plague before it evolved to optimally cause invasive infections in mammals.

[The Antonine plague].

Science.gov (United States)

Haas, Charles

2006-01-01

During the reign of Marcus Aurelius, the Roman Empire was struck by a long and destructive epidemic. It began in Mesopotamia in late AD 165 or early AD 166 during Verus' Parthian campaign, and quickly spread to Rome. It lasted at least until the death of Marcus Aurelius in AD 180 and likely into the early part of Commodus' reign. Its victims were "innumerable". Galen had first-hand knowledge of the disease. He was in Rome when the plague reached the city in AD 166. He was also present during an outbreak among troops stationed at Aquileia during the winter of AD 168-169. His references to the plague are scattered and brief but enough information is available to firmly identify the plague as smallpox. His description of the exanthema is fairly typical of the smallpox rash, particularly in the hemorrhagic phase of the disease.

Comparative analysis of crayfish marketing in selected markets of ...

African Journals Online (AJOL)

Comparative analysis of crayfish marketing in selected markets of Akwa Ibom and Abia States, Nigeria. ... It specifically looked at market integration, costs and return, marketing margin, marketing ... EMAIL FULL TEXT EMAIL FULL TEXT

Differences in aggression, activity and boldness between native and introduced populations of an invasive crayfish

Science.gov (United States)

Pintor, L.M.; Sih, A.; Bauer, M.L.

2008-01-01

Aggressiveness, along with foraging voracity and boldness, are key behavioral mechanisms underlying the competitive displacement and invasion success of exotic species. However, do aggressiveness, voracity and boldness of the invader depend on the presence of an ecologically similar native competitor in the invaded community? We conducted four behavioral assays to compare aggression, foraging voracity, threat response and boldness to forage under predation risk of multiple populations of exotic signal crayfish Pacifastacus leniusculus across its native and invaded range with and without a native congener, the Shasta crayfish P. fortis. We predicted that signal crayfish from the invaded range and sympatric with a native congener (IRS) should be more aggressive to outcompete a close competitor than populations from the native range (NR) or invaded range and allopatric to a native congener (IRA). Furthermore, we predicted that IRS populations of signal crayfish should be more voracious, but less bold to forage under predation risk since native predators and prey likely possess appropriate behavioral responses to the invader. Contrary to our predictions, results indicated that IRA signal crayfish were more aggressive towards conspecifics and more voracious and active foragers, yet also bolder to forage under predation risk in comparison to NR and IRS populations, which did not differ in behavior. Higher aggression/voracity/ boldness was positively correlated with prey consumption rates, and hence potential impacts on prey. We suggest that the positive correlations between aggression/voracity/boldness are the result of an overall aggression syndrome. Results of stream surveys indicated that IRA streams have significantly lower prey biomass than in IRS streams, which may drive invading signal crayfish to be more aggressive/voracious/bold to acquire resources to establish a population. ?? 2008 The Authors.

ECOLOGICAL CHARACTERISATION OF STREAMS IN TUSCANY (ITALY FOR THE MANAGEMENT OF THE THREATENED CRAYFISH AUSTROPOTAMOBIUS PALLIPES COMPLEX

Directory of Open Access Journals (Sweden)

RENAI B.

2006-01-01

Full Text Available Any initiative aimed at the management of a threatened species needs a good knowledge of its environmental requirements. Aims of this study were to individuate suitable areas for the reintroduction of crayfish species belonging to the Austropotamobius pallipes complex and to evaluate the causes of the local extinction in Tuscany (Italy of some populations. Between May 2003 and September 2004, we collected ecological data from 19 streams of 4 catchments, 9 watercourses where crayfish were present (WI and 10 where they were present in the recent past and absent now (WO, and we compared them. Multivariate analyses were performed using chemico-physical and biotic parameters to examine the relationships between their values and the presence of crayfish. The results did not allow us to find significant differences between the two categories of streams, suggesting their suitability for crayfish reintroduction.

Comparative study of freshwater crayfish, Cherax spp. (crustaceae: decapoda: parastacidae) from Papua, Indonesia based on length-weight analysis

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Hamidah, H.; Abinawanto, Bowolaksono, A.

2017-07-01

The freshwater crayfish is one of the most important fish species as the protein resources. Lake and rivers are the habitat of crayfish in Papua. Morphological characters of crayfish, such as color, total body lengths (L) and body weight (W) were influenced by the habitat. The purpose of the study, therefore, was to compare the total body length and body weight as well as the unique color of crayfish from Uter lake (Atinjo district), Seremuk river (Haha village), Baliem river (Pike village; Hubukiak district, Jayawijaya), and Baliem river (Wesaput village; Wesaput district). Length-weight (body length; LB versus wet weight; WWT) relationships were determined for male and female crayfish (Cherax spp.) The length-weight relationships of total individuals was W = 0,022215.L3,159. This regression differed significantly (R2 = 97.5 %) between locations. Both males and females exhibited positive allometric growth as statistical difference was observed in the mean of the wet weight and body length between males and females. Besides, Canonical function was subjected to determine population distribution based on length-weight data.

Enzootic plague foci, Algeria

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M.A. Malek

2015-03-01

Full Text Available In Algeria, PCR sequencing of pla, glpD and rpoB genes found Yersinia pestis in 18/237 (8% rodents of five species, including Apodemus sylvaticus, previously undescribed as pestiferous; and disclosed three new plague foci. Multiple spacer typing confirmed a new Orientalis variant. Rodent survey should be reinforced in this country hosting reemerging plague.

The future of the indigenous freshwater crayfish Austropotamobius italicus in Basque Country streams: Is it possible to survive being an inconvenient species?

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L. García-Arberas

2009-01-01

Full Text Available The white-clawed freshwater crayfish Austropotamobius italicus is listed as “vulnerable” in the Spanish Red List of threatened species, but local legislation varies among Spanish regions. Thus, while in some places the species is classified as “in risk of extinction” and various plans of conservation and restoration have been implemented, in the Basque Country and other regions the species is not listed. The distribution of the white-clawed crayfish in the province of Biscay (Basque Country was studied from 1993 to 2007 at more than 600 sampling locations. Results show that 108 streams were inhabited by the native crayfish species A. italicus while 137 streams were inhabited by non-native signal crayfish Pacifastacus leniusculus or red-swamp crayfish Procambarus clarkii. The spread of non-native crayfish is not the only threat to the native species whose survival is also closely dependent on how watersheds are managed. Most A. italicus populations inhabit headwaters, where forestry activities are very important. The presence of native crayfish in heavily forested areas results in a conflict of interests and makes its conservation particularly difficult. We employed a SWOT analysis – an assessment and decision tool commonly used in marketing and business – to evaluate the situation of the native white-clawed crayfish in Biscay, a province characterized by very high demographic pressure. SWOT analysis has proved to be a useful diagnostic tool and can help develop better and more accurate management strategies for the conservation of native crayfish threatened by multiple stressors.

Plague Vaccines: Status and Future.

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Sun, Wei

2016-01-01

Three major plague pandemics caused by the gram-negative bacterium Yersinia pestis have killed nearly 200 million people in human history. Due to its extreme virulence and the ease of its transmission, Y. pestis has been used purposefully for biowarfare in the past. Currently, plague epidemics are still breaking out sporadically in most of parts of the world, including the United States. Approximately 2000 cases of plague are reported each year to the World Health Organization. However, the potential use of the bacteria in modern times as an agent of bioterrorism and the emergence of a Y. pestis strain resistant to eight antibiotics bring out severe public health concerns. Therefore, prophylactic vaccination against this disease holds the brightest prospect for its long-term prevention. Here, we summarize the progress of the current vaccine development for counteracting plague.

ANNUAL ACTIVITY OF THE NOBLE CRAYFISH (ASTACUS ASTACUS IN THE ORLJAVA RIVER (CROATIA

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FALLER M.

2006-07-01

Full Text Available We studied the annual activity of the noble crayfish (Astacus astacus at three sites along the Orljava River, in the continental part of Croatia, between August 2003 and September 2004. Each site represented the typical characteristics of the upper, middle and lower section of the river (5, 24 and 37 km from the spring, respectively. The biggest population size was recorded on the most upstream site, with greatest structural variability of bottom, high biotic index, and the lowest mean water temperature. Males dominated in catch during the whole research period (total sex ratio was 1.77 males: 1 female. The number of caught crayfish fluctuated during the year and their activity was positively correlated with the water temperature. The crayfish catch within the two downstream sites was dramatically lower in the autumn 2004 then the year before. No obvious reason could be found; therefore we concluded that this was probably result of natural fluctuations in population. Males were significantly longer than females on all three sites. Males and females had similar percentages of injuries, mainly on claws and antennae. Crayfish were active during the whole year, even when water temperature was just 1°C. Phases of life cycle (moulting, active cement glands, mating, hatchlings occurred a month later in our population than in the Northern Europe populations, probably as a consequence of differences in the climate.

Histological analysis of thelohaniasis in white-clawed crayfish Austropotamobius pallipes complex

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Quaglio F.

2011-09-01

Full Text Available From 2004 to 2006, a parasitological survey aimed at the detection of the microsporidian parasite Thelohania contejeani Henneguy was carried out on 177 wild white-clawed crayfish (Austropotamobius pallipes complex captured in six streams and rivers of the province of Belluno in north-eastern Italy. Microscopical examination of the skeletal muscles, and histological analysis applying different histochemical stains to full transverse and sagittal sections of the cephalothorax and abdomen were carried out. Transmission electron microscopy (TEM was also conducted on the parasites recovered during the survey. Out of 177 crayfish examined, Thelohania contejeani (Microsporidia, Thelohaniidae was present in only one crayfish from the Vena d’oro creek. The parasite was detected in the skeletal muscles in several developmental stages, including mature spores, which represented the most common stage recovered. Sporophorous vesicles were also present. Histological examination revealed that the fibres of the skeletal, cardiac and intestinal muscles were filled with spores. Melanin infiltrations were focally present in the infected striated muscles. The gill phagocytic nephrocytes were engulfed by small masses of spores. Among the staining techniques applied, Crossman’s trichrome stain represented the most effective method of detecting T. contejeani.

Patterns of Human Plague in Uganda, 2008-2016.

Science.gov (United States)

Forrester, Joseph D; Apangu, Titus; Griffith, Kevin; Acayo, Sarah; Yockey, Brook; Kaggwa, John; Kugeler, Kiersten J; Schriefer, Martin; Sexton, Christopher; Ben Beard, C; Candini, Gordian; Abaru, Janet; Candia, Bosco; Okoth, Jimmy Felix; Apio, Harriet; Nolex, Lawrence; Ezama, Geoffrey; Okello, Robert; Atiku, Linda; Mpanga, Joseph; Mead, Paul S

2017-09-01

Plague is a highly virulent fleaborne zoonosis that occurs throughout many parts of the world; most suspected human cases are reported from resource-poor settings in sub-Saharan Africa. During 2008-2016, a combination of active surveillance and laboratory testing in the plague-endemic West Nile region of Uganda yielded 255 suspected human plague cases; approximately one third were laboratory confirmed by bacterial culture or serology. Although the mortality rate was 7% among suspected cases, it was 26% among persons with laboratory-confirmed plague. Reports of an unusual number of dead rats in a patient's village around the time of illness onset was significantly associated with laboratory confirmation of plague. This descriptive summary of human plague in Uganda highlights the episodic nature of the disease, as well as the potential that, even in endemic areas, illnesses of other etiologies might be being mistaken for plague.

A global review of freshwater crayfish temperature tolerance, preference, and optimal growth

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Westhoff, Jacob T.; Rosenberger, Amanda E.

2016-01-01

Conservation efforts, environmental planning, and management must account for ongoing ecosystem alteration due to a changing climate, introduced species, and shifting land use. This type of management can be facilitated by an understanding of the thermal ecology of aquatic organisms. However, information on thermal ecology for entire taxonomic groups is rarely compiled or summarized, and reviews of the science can facilitate its advancement. Crayfish are one of the most globally threatened taxa, and ongoing declines and extirpation could have serious consequences on aquatic ecosystem function due to their significant biomass and ecosystem roles. Our goal was to review the literature on thermal ecology for freshwater crayfish worldwide, with emphasis on studies that estimated temperature tolerance, temperature preference, or optimal growth. We also explored relationships between temperature metrics and species distributions. We located 56 studies containing information for at least one of those three metrics, which covered approximately 6 % of extant crayfish species worldwide. Information on one or more metrics existed for all 3 genera of Astacidae, 4 of the 12 genera of Cambaridae, and 3 of the 15 genera of Parastacidae. Investigations employed numerous methodological approaches for estimating these parameters, which restricts comparisons among and within species. The only statistically significant relationship we observed between a temperature metric and species range was a negative linear relationship between absolute latitude and optimal growth temperature. We recommend expansion of studies examining the thermal ecology of freshwater crayfish and identify and discuss methodological approaches that can improve standardization and comparability among studies.

The first record of translocated white-clawed crayfish from the Austropotamobius pallipes complex in Sardinia (Italy

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Julien Amouret

2015-03-01

Full Text Available The white-clawed crayfish Austropotamobius pallipes complex is native to Europe, being present in 18 European countries, Italy included. However, the number and abundance of its populations are today restricted and it has been recently classified as “endangered” by IUCN (International Union for Conservation of Nature. Here, we report the first record of this freshwater crayfish in Sardinia Island (Italy. Using a fragment of the mitochondrial DNA 16S rRNA gene, we identified three haplotypes that correspond to the A. italicus meridionalis subclade. We provide information about the sampling area, population density and finally discuss hypotheses about the occurrence of this population in Sardinia, comparing it with other Mediterranean populations. Our results improve the existing knowledge about the phylogeography of the taxon across Italy, confirming its complex pattern of distribution. In addition to the non-native status of the Sardinian A. i. meridionalis crayfish, we showed that the most proximal Mediterranean population of white-clawed crayfish existing in Corsica belongs to A. pallipes from Southern France.

[The plague: An overview and hot topics].

Science.gov (United States)

Galy, A; Loubet, P; Peiffer-Smadja, N; Yazdanpanah, Y

2018-04-05

Plague is a bacterial zoonosis caused by Yersinia pestis, usually found in fleas and small rodents that constitute the reservoir of the disease. It is transmitted to humans by flea bite, contact with rodents or inhalation of infected droplets. There are three clinical forms: bubonic plague, pulmonary plague and septicemic plague. The usual presentation is a flu-like syndrome possibly accompanied by an inflammatory lymphadenopathy which appears after 1 to 7days of incubation. Bubonic plague has a case fatality rate of about 50% while other forms of plague are almost always fatal without treatment. Diagnosis can be confirmed by usual bacteriological techniques (Gram examination, culture) but also by serological examination, use of rapid diagnostic tests or PCR. Although aminoglycosides are traditionally regarded as the most effective treatment, fluoroquinolones or cyclins are currently recommended in France. Plague is one of the re-emerging diseases according to the WHO and Madagascar suffered in 2017 the most important plague epidemic of the 21st century with more than 2000 cases and 200 deaths. Peru and the Democratic Republic of Congo are also considered endemic areas. Public health measures and a relentless fight against poverty are the cornerstone of the control of the disease. Vaccine improvement in endemic areas may also play an important role. Copyright © 2018 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Trade routes and plague transmission in pre-industrial Europe.

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Yue, Ricci P H; Lee, Harry F; Wu, Connor Y H

2017-10-11

Numerous historical works have mentioned that trade routes were to blame for the spread of plague in European history, yet this relationship has never been tested by quantitative evidence. Here, we resolve the hypothetical role of trade routes through statistical analysis on the geo-referenced major trade routes in the early modern period and the 6,656 geo-referenced plague outbreak records in AD1347-1760. Ordinary Least Square (OLS) estimation results show that major trade routes played a dominant role in spreading plague in pre-industrial Europe. Furthermore, the negative correlation between plague outbreaks and their distance from major trade ports indicates the absence of a permanent plague focus in the inland areas of Europe. Major trade routes decided the major plague outbreak hotspots, while navigable rivers determined the geographic pattern of sporadic plague cases. A case study in Germany indicates that plague penetrated further into Europe through the local trade route network. Based on our findings, we propose the mechanism of plague transmission in historical Europe, which is imperative in demonstrating how pandemics were spread in recent human history.

Vector control improves survival of three species of prairie dogs (Cynomys) in areas considered enzootic for plague

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Biggins, Dean E.; Godbey, Jerry L.; Gage, Kenneth L.; Carter, Leon G.; Montenieri, John A.

2010-01-01

Plague causes periodic epizootics that decimate populations of prairie dogs (PDs) (Cynomys), but the means by which the causative bacterium (Yersinia pestis) persists between epizootics are poorly understood. Plague epizootics in PDs might arise as the result of introductions of Y. pestis from sources outside PD colonies. However, it remains possible that plague persists in PDs during interepizootic periods and is transmitted at low rates among highly susceptible individuals within and between their colonies. If this is true, application of vector control to reduce flea numbers might reduce mortality among PDs. To test whether vector control enhances PD survival in the absence of obvious plague epizootics, we reduced the numbers of fleas (vectors for Y. pestis) 96–98% (1 month posttreatment) on 15 areas involving three species of PDs (Cynomys leucurus, Cynomys parvidens in Utah, and Cynomys ludovicianus in Montana) during 2000–2004 using deltamethrin dust delivered into burrows as a pulicide. Even during years without epizootic plague, PD survival rates at dusted sites were 31–45% higher for adults and 2–34% higher for juveniles compared to survival rates at nondusted sites. Y. pestis was cultured from 49 of the 851 flea pools tested (6882 total fleas) and antibodies against Y. pestis were identified in serum samples from 40 of 2631 PDs. Although other explanations are possible, including transmission of other potentially fatal pathogens by fleas, ticks, or other ectoparasites, our results suggest that plague might be maintained indefinitely in PD populations in the absence of free epizootics and widespread mortality among these animals. If PDs and their fleas support enzootic cycles of plague transmission, there would be important implications for the conservation of these animals and other species.

Natural crayfish clone as emerging model for various biological ...

Indian Academy of Sciences (India)

Home; Journals; Journal of Biosciences; Volume 36; Issue 2. Marmorkrebs: Natural crayfish clone as emerging model for various biological disciplines. Günter Vogt. Mini-review Volume 36 Issue 2 June 2011 pp 377-382. Fulltext. Click here to view fulltext PDF. Permanent link:

A Taxonomic Update of Small Mammal Plague Reservoirs in South America.

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Bonvicino, Cibele R; Oliveira, João A; Cordeiro-Estrela, Pedro; D'andrea, Paulo S; Almeida, Alzira M P

2015-10-01

Plague is a disease of epidemic potential that may emerge with discontinuous outbreaks. In South America, 50 wild rodent species have been identified as plague reservoirs, in addition to one lagomorph and two marsupials. To review the nomenclature of plague reservoirs, we examined specimens collected in plague foci, carried out new surveys in Brazilian plague regions, and re-evaluated the nomenclature of South American reservoirs on the basis of the current literature. Five of the 15 species involved with plague in Argentina, three of 10 species involved with plague in Bolivia, three of the seven species involved with plague in Peru, five of the nine species involved with plague in Ecuador, and six of the nine species involved with plague in Brazil have undergone taxonomic changes. In the last 20 years, plague cases were recorded in Bolivia, Brazil, Ecuador, and Peru. These four countries have a high rodent species richness in plague foci, a fact that may be decisive for the maintenance of plague in the wild.

Who is the boss? Individual recognition memory and social hierarchy formation in crayfish.

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Jiménez-Morales, Nayeli; Mendoza-Ángeles, Karina; Porras-Villalobos, Mercedes; Ibarra-Coronado, Elizabeth; Roldán-Roldán, Gabriel; Hernández-Falcón, Jesús

2018-01-01

Under laboratory conditions, crayfish establish hierarchical orders through agonistic encounters whose outcome defines the dominant one and one, or more, submissive animals. These agonistic encounters are ritualistic, based on threats, pushes, attacks, grabs, and avoidance behaviors that include retreats and escape responses. Agonistic behavior in a triad of unfamiliar, size-matched animals is intense on the first day of social interaction and the intensity fades on daily repetitions. The dominant animal keeps its status for long periods, and the submissive ones seem to remember 'who the boss is'. It has been assumed that animals remember and recognize their hierarchical status by urine signals, but the putative substance mediating this recognition has not been reported. The aim of this work was to characterize this hierarchical recognition memory. Triads of unfamiliar crayfish (male animals, size and weight-matched) were faced during standardized agonistic protocols for five consecutive days to analyze memory acquisition dynamics (Experiment 1). In Experiment 2, dominant crayfish were shifted among triads to disclose whether hierarchy depended upon individual recognition memory or recognition of status. The maintenance of the hierarchical structure without behavioral reinforcement was assessed by immobilizing the dominant animal during eleven daily agonistic encounters, and considering any shift in the dominance order (Experiment 3). Standard amnesic treatments (anisomycin, scopolamine or cold-anesthesia) were given to all members of the triads immediately after the first interaction session to prevent individual recognition memory consolidation and evaluate its effect on the hierarchical order (Experiment 4). Acquisition of hierarchical recognition occurs at the first agonistic encounter and agonistic behavior gradually diminishes in the following days; animals keep their hierarchical order despite the inability of the dominant crayfish to attack the submissive

Plague Prevention

Science.gov (United States)

... visit this page: About CDC.gov . Plague Home Ecology & Transmission Symptoms Diagnosis & Treatment Maps & Statistics Info for ... or working outdoors. Products containing DEET can be applied to the skin as well as clothing and ...

It takes time to see the menu from the body: an experiment on stable isotope composition in freshwater crayfishes

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Jussila J.

2015-01-01

Full Text Available For many applications and ecological studies in which wild individuals are brought to laboratory it would be essential to know accurately how fast novel diet is reflected in composition of different tissues. To study the effects of two different diets on the stable isotope composition of freshwater crayfish muscle and hemolymph, we conducted a three month experiment on noble crayfish (Astacus astacus and signal crayfish (Pacifastacus leniusculus by feeding them sweet corn (Zea mays or Baltic herring (Clupea harengus membras as novel food. During the experiment, the crayfish were given 0.4 g of selected food daily and the amount consumed was recorded. The samples for the stable isotope analyses were taken at the commencement of the experiment (initial control and three times (hemolymph or twice (muscle tissue during the experiment. We found that stable isotope changes can be similarly, and rather slowly, detected from muscle tissue and hemolymph under studied conditions. Hemolymph sampling, being non-lethal, can be recommended as a practical sampling method. Our results confirm earlier reports according to which diet changes reflect to crayfish isotope ratios slowly implying that isotope ratios indicate long-term diet.

The Sensitivity of the Crayfish Reward System to Mammalian Drugs of Abuse.

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Shipley, Adam T; Imeh-Nathaniel, Adebobola; Orfanakos, Vasiliki B; Wormack, Leah N; Huber, Robert; Nathaniel, Thomas I

2017-01-01

The idea that addiction occurs when the brain is not able to differentiate whether specific reward circuits were triggered by adaptive natural rewards or falsely activated by addictive drugs exist in several models of drug addiction. The suitability of crayfish ( Orconectes rusticus ) for drug addiction research arises from developmental variation of growth, life span, reproduction, behavior and some quantitative traits, especially among isogenic mates reared in the same environment. This broad spectrum of traits makes it easier to analyze the effect of mammalian drugs of abuse in shaping behavioral phenotype. Moreover, the broad behavioral repertoire allows the investigation of self-reinforcing circuitries involving appetitive and exploratory motor behavior, while the step-wise alteration of the phenotype by metamorphosis allows accurate longitudinal analysis of different behavioral states. This paper reviews a series of recent experimental findings that evidence the suitability of crayfish as an invertebrate model system for the study of drug addiction. Results from these studies reveal that unconditioned exposure to mammalian drugs of abuse produces a variety of stereotyped behaviors. Moreover, if presented in the context of novelty, drugs directly stimulate exploration and appetitive motor patterns along with molecular processes for drug conditioned reward. Findings from these studies indicate the existence of drug sensitive circuitry in crayfish that facilitates exploratory behavior and appetitive motor patterns via increased incentive salience of environmental stimuli or by increasing exploratory motor patterns. This work demonstrates the potential of crayfish as a model system for research into the neural mechanisms of addiction, by contributing an evolutionary, comparative context to our understanding of natural reward as an important life-sustaining process.

The Sensitivity of the Crayfish Reward System to Mammalian Drugs of Abuse

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Adam T. Shipley

2017-12-01

Full Text Available The idea that addiction occurs when the brain is not able to differentiate whether specific reward circuits were triggered by adaptive natural rewards or falsely activated by addictive drugs exist in several models of drug addiction. The suitability of crayfish (Orconectes rusticus for drug addiction research arises from developmental variation of growth, life span, reproduction, behavior and some quantitative traits, especially among isogenic mates reared in the same environment. This broad spectrum of traits makes it easier to analyze the effect of mammalian drugs of abuse in shaping behavioral phenotype. Moreover, the broad behavioral repertoire allows the investigation of self-reinforcing circuitries involving appetitive and exploratory motor behavior, while the step-wise alteration of the phenotype by metamorphosis allows accurate longitudinal analysis of different behavioral states. This paper reviews a series of recent experimental findings that evidence the suitability of crayfish as an invertebrate model system for the study of drug addiction. Results from these studies reveal that unconditioned exposure to mammalian drugs of abuse produces a variety of stereotyped behaviors. Moreover, if presented in the context of novelty, drugs directly stimulate exploration and appetitive motor patterns along with molecular processes for drug conditioned reward. Findings from these studies indicate the existence of drug sensitive circuitry in crayfish that facilitates exploratory behavior and appetitive motor patterns via increased incentive salience of environmental stimuli or by increasing exploratory motor patterns. This work demonstrates the potential of crayfish as a model system for research into the neural mechanisms of addiction, by contributing an evolutionary, comparative context to our understanding of natural reward as an important life-sustaining process.

Short Note Invasive Australian crayfish Cherax quadricarinatus in ...

African Journals Online (AJOL)

Most crayfish were between 50 and 59.9 mm carapace length. Males (average 82.6 g) were significantly heavier than females (37.2 g) and males were larger in carapace length, carapace width, chela length and chela width. A feral population of C. quadricarinatus is now established in the Sanyati Basin. Possible modes of ...

Paltry past-precipitation: Predisposing prairie dogs to plague?

Science.gov (United States)

Eads, David; Biggins, Dean E.

2017-01-01

The plague bacterium Yersinia pestis was introduced to California in 1900 and spread rapidly as a sylvatic disease of mammalian hosts and flea vectors, invading the Great Plains in the United States by the 1930s to 1940s. In grassland ecosystems, plague causes periodic, devastating epizootics in colonies of black-tailed prairie dogs (Cynomys ludovicianus), sciurid rodents that create and maintain subterranean burrows. In doing so, plague inhibits prairie dogs from functioning as keystone species of grassland communities. The rate at which fleas transmit Y. pestis is thought to increase when fleas are abundant. Flea densities can increase during droughts when vegetative production is reduced and herbivorous prairie dogs are malnourished and have weakened defenses against fleas. Epizootics of plague have erupted frequently in prairie dogs during years in which precipitation was plentiful, and the accompanying cool temperatures might have facilitated the rate at which fleas transmitted Y. pestis. Together these observations evoke the hypothesis that transitions from dry-to-wet years provide conditions for plague epizootics in prairie dogs. Using generalized linear models, we analyzed a 24-year dataset on the occurrence of plague epizootics in 42 colonies of prairie dogs from Colorado, USA, 1982–2005. Of the 33 epizootics observed, 52% erupted during years with increased precipitation in summer. For the years with increased summer precipitation, if precipitation in the prior growing season declined from the maximum of 502 mm to the minimum of 200 mm, the prevalence of plague epizootics was predicted to increase 3-fold. Thus, reduced precipitation may have predisposed prairie dogs to plague epizootics when moisture returned. Biologists sometimes assume dry conditions are detrimental for plague. However, 48% of epizootics occurred during years in which precipitation was scarce in summer. In some cases, an increased abundance of fleas during dry years might

Enhanced Macrophage M1 Polarization and Resistance to Apoptosis Enable Resistance to Plague.

Science.gov (United States)

Pachulec, Emilia; Abdelwahed Bagga, Rym Ben; Chevallier, Lucie; O'Donnell, Hope; Guillas, Chloé; Jaubert, Jean; Montagutelli, Xavier; Carniel, Elisabeth; Demeure, Christian E

2017-09-15

Susceptibility to infection is in part genetically driven, and C57BL/6 mice resist various pathogens through the proinflammatory response of their M1 macrophages (MPs). However, they are susceptible to plague. It has been reported elsewhere that Mus spretus SEG mice resist plague and develop an immune response characterized by a strong recruitment of MPs. The responses of C57BL/6 and SEG MPs exposed to Yersinia pestis in vitro were examined. SEG MPs exhibit a stronger bactericidal activity with higher nitric oxide production, a more proinflammatory polarized cytokine response, and a higher resistance to Y. pestis-induced apoptosis. This response was not specific to Y. pestis and involved a reduced sensitivity to M2 polarization/signal transducer and activator of transcription 6 activation and inhibition of caspase 8. The enhanced M1 profile was inducible in C57BL/6 MPs in vitro, and when transferred to susceptible C57BL/6 mice, these MPs significantly increased survival of bubonic plague. MPs can develop an enhanced functional profile beyond the prototypic M1, characterized by an even more potent proinflammatory response coordinated with resistance to killing. This programming plays a key role in the plague-resistance phenotype and may be similarly significant in other highly lethal infections, suggesting that orienting the MP response may represent a new therapeutic approach. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

ROUNDTABLE SESSION 3: PHYLOGENY OF EUROPEAN CRAYFISH – IMPROVING THE TAXONOMY OF EUROPEAN CRAYFISH FOR A BETTER CONSERVATION

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SCHULZ H. K.

2005-07-01

Full Text Available This paper summarizes the various themes discussed in a roundtable session on the uses and usefulness of genetics for conservation of our European crayfish heritage. After reviewing the importance of characterizing the different genetic stocks (ESU: Evolutionary Significant Units of a species, where morphological criteria used for taxonomy, are utilizable with caution, the present state of knowledge of the phylogeny of European species was determined, in particular for the genus Austropotamobius which occupies most studies. There was a lively debate on the elevation to species rank of A. italicus. The status of knowledge of the taxonomy of Astacus astacus has been presented. Finally, given a major increase in works describing the genetic variability of natural populations of European crayfish, it was evident that an up to date inventory of the different research teams in this field should be developed, for several reasons – (i to describe these teams and their managers (thus facilitating contact (ii to list the species studied and the markers used (iii to give some recommendations on standardizing the use of certain markers or genes so as to allow comparison between the results collected by the various teams, and to apply them on a broader geographic scale.

Glutathionylation of Yersinia pestis LcrV and Its Effects on Plague Pathogenesis.

Science.gov (United States)

Mitchell, Anthony; Tam, Christina; Elli, Derek; Charlton, Thomas; Osei-Owusu, Patrick; Fazlollahi, Farbod; Faull, Kym F; Schneewind, Olaf

2017-05-16

Glutathionylation, the formation of reversible mixed disulfides between glutathione and protein cysteine residues, is a posttranslational modification previously observed for intracellular proteins of bacteria. Here we show that Yersinia pestis LcrV, a secreted protein capping the type III secretion machine, is glutathionylated at Cys 273 and that this modification promotes association with host ribosomal protein S3 (RPS3), moderates Y. pestis type III effector transport and killing of macrophages, and enhances bubonic plague pathogenesis in mice and rats. Secreted LcrV was purified and analyzed by mass spectrometry to reveal glutathionylation, a modification that is abolished by the codon substitution Cys 273 Ala in lcrV Moreover, the lcrV C273A mutation enhanced the survival of animals in models of bubonic plague. Investigating the molecular mechanism responsible for these virulence attributes, we identified macrophage RPS3 as a ligand of LcrV, an association that is perturbed by the Cys 273 Ala substitution. Furthermore, macrophages infected by the lcrV C273A variant displayed accelerated apoptotic death and diminished proinflammatory cytokine release. Deletion of gshB , which encodes glutathione synthetase of Y. pestis , resulted in undetectable levels of intracellular glutathione, and we used a Y. pestis Δ gshB mutant to characterize the biochemical pathway of LcrV glutathionylation, establishing that LcrV is modified after its transport to the type III needle via disulfide bond formation with extracellular oxidized glutathione. IMPORTANCE Yersinia pestis , the causative agent of plague, has killed large segments of the human population; however, the molecular bases for the extraordinary virulence attributes of this pathogen are not well understood. We show here that LcrV, the cap protein of bacterial type III secretion needles, is modified by host glutathione and that this modification contributes to the high virulence of Y. pestis in mouse and rat

Interspecific comparisons of sylvatic plague in prairie dogs

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Cully, J.F.; Williams, E.S.

2001-01-01

Of the 3 major factors (habitat loss, poisoning, and disease) that limit abundance of prairie dogs today, sylvatic plague caused by Yersinia pestis is the 1 factor that is beyond human control. Plague epizootics frequently kill >99% of prairie dogs in infected colonies. Although epizootics of sylvatic plague occur throughout most of the range of prairie dogs in the United States and are well described, long-term maintenance of plague in enzootic rodent species is not well documented or understood. We review dynamics of plague in white-tailed (Cynomys leucurus), Gunnison's (C. gunnisoni), and black-tailed (C. ludovicianus) prairie dogs, and their rodent and flea associates. We use epidemiologic concepts to support an enzootic hypothesis in which the disease is maintained in a dynamic state, which requires transmission of Y. pestis to be slower than recruitment of new susceptible mammal hosts. Major effects of plague are to reduce colony size of black-tailed prairie dogs and increase intercolony distances within colony complexes. In the presence of plague, black-tailed prairie dogs will probably survive in complexes of small colonies that are usually >3 km from their nearest neighbor colonies.

Crayfish: a newly recognized vehicle for vibrio infections.

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Bean, N H; Maloney, E K; Potter, M E; Korazemo, P; Ray, B; Taylor, J P; Seigler, S; Snowden, J

1998-10-01

We conducted a 1-year case-control study of sporadic vibrio infections to identify risk factors related to consumption of seafood products in two coastal areas of Louisiana and Texas. Twenty-six persons with sporadic vibrio infections and 77 matched controls were enrolled. Multivariate analysis revealed that crayfish (P Vibrio parahemolyticus infection (OR 9.24, P vibrio infection.

CRAYFISH AND ITS CULTURE IN UKRAINE. THEMATIC REFERENCES LIST

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I. Hrytsyniak

2014-09-01

Full Text Available Purpose. To compile a thematic references list on the problems of biology, physiology, pathology and crayfish breeding in Ukraine. Methodology. As the search base for the realization of the purpose was the scientific library stock of the Institute of Fisheries NAAS. The methods that have been preferred were both integrated and selective. Findings. We prepared a thematic reference list of the main scientific works, such as collections of scientific papers, proceedings of international scientific conferences, articles and candidate’s thesis abstracts on the biology of crustaceans and their cultivation in Ukraine, including the literature sources since 1958. The bibliography contains 37 publications of the Institute of Fisheries NAAS scientific library stock, in alphabetical order, and described according to DSTU GOST 7.1:2006 «System of standards on information, librarianship and publishing. Bibliographic entry. Bibliographic description. General requirements and rules». Practical value. The list may be helpful for experts, scientists, students, who are interested in problems of crayfish biology and culture.

[ON THE ORIGIN OF HYPERVIRULENCE OF THE CAUSATIVE AGENT OF PLAGUE].

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Anisimov, N V; Kislichkina, A A; Platonov, M E; Evseeva, V V; Kadnikova, L A; Lipatnikova, N A; Bogun, A G; Dentovskaya, S V; Anisimov, A P

2016-01-01

The attempt to combine Yersinia pseudotuberculosis and Yersinia pestis into one species has been unsupported by microbiologists due to the specific features of the epidemiology and clinical presentations of their induced diseases and to basic differences in their virulence. Pseudotuberculosis is predominantly a relatively mild human intestinal infection transmitted through contaminated food and plague is an acute generalized disease with high mortality, which is most frequently transmitted by the bites of infected fleas. Y. pestis hypervirulence, the ability of single bacteria to ensure the development of predagonal bacteriemia in rodents, which is sufficient to contaminate the fleas, is one of the main events during pathogen adaptation to a new ecological niche. By analyzing the data of molecular typing of the representative kits of naturally occurring Y. pestis isolates, the authois consider the issues of formation of intraspecies groups with universal hypervirulence, as well as biovars that are highly virulent only to their major host. A strategy for searching for selective virulence factors, the potential molecular targets for vaccination and etiotropic treatment of plague, is discussed.

Patterns of Human Plague in Uganda, 2008–2016

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Forrester, Joseph D.; Apangu, Titus; Griffith, Kevin; Acayo, Sarah; Yockey, Brook; Kaggwa, John; Kugeler, Kiersten J.; Schriefer, Martin; Sexton, Christopher; Ben Beard, C.; Candini, Gordian; Abaru, Janet; Candia, Bosco; Okoth, Jimmy Felix; Apio, Harriet; Nolex, Lawrence; Ezama, Geoffrey; Okello, Robert; Atiku, Linda; Mpanga, Joseph

2017-01-01

Plague is a highly virulent fleaborne zoonosis that occurs throughout many parts of the world; most suspected human cases are reported from resource-poor settings in sub-Saharan Africa. During 2008–2016, a combination of active surveillance and laboratory testing in the plague-endemic West Nile region of Uganda yielded 255 suspected human plague cases; approximately one third were laboratory confirmed by bacterial culture or serology. Although the mortality rate was 7% among suspected cases, it was 26% among persons with laboratory-confirmed plague. Reports of an unusual number of dead rats in a patient’s village around the time of illness onset was significantly associated with laboratory confirmation of plague. This descriptive summary of human plague in Uganda highlights the episodic nature of the disease, as well as the potential that, even in endemic areas, illnesses of other etiologies might be being mistaken for plague. PMID:28820134

Mapping risk of plague in Qinghai-Tibetan Plateau, China.

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Qian, Quan; Zhao, Jian; Fang, Liqun; Zhou, Hang; Zhang, Wenyi; Wei, Lan; Yang, Hong; Yin, Wenwu; Cao, Wuchun; Li, Qun

2014-07-10

Qinghai-Tibetan Plateau of China is known to be the plague endemic region where marmot (Marmota himalayana) is the primary host. Human plague cases are relatively low incidence but high mortality, which presents unique surveillance and public health challenges, because early detection through surveillance may not always be feasible and infrequent clinical cases may be misdiagnosed. Based on plague surveillance data and environmental variables, Maxent was applied to model the presence probability of plague host. 75% occurrence points were randomly selected for training model, and the rest 25% points were used for model test and validation. Maxent model performance was measured as test gain and test AUC. The optimal probability cut-off value was chosen by maximizing training sensitivity and specificity simultaneously. We used field surveillance data in an ecological niche modeling (ENM) framework to depict spatial distribution of natural foci of plague in Qinghai-Tibetan Plateau. Most human-inhabited areas at risk of exposure to enzootic plague are distributed in the east and south of the Plateau. Elevation, temperature of land surface and normalized difference vegetation index play a large part in determining the distribution of the enzootic plague. This study provided a more detailed view of spatial pattern of enzootic plague and human-inhabited areas at risk of plague. The maps could help public health authorities decide where to perform plague surveillance and take preventive measures in Qinghai-Tibetan Plateau.

Drug-sensitive reward in crayfish: an invertebrate model system for the study of SEEKING, reward, addiction, and withdrawal.

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Huber, Robert; Panksepp, Jules B; Nathaniel, Thomas; Alcaro, Antonio; Panksepp, Jaak

2011-10-01

In mammals, rewarding properties of drugs depend on their capacity to activate appetitive motivational states. With the underlying mechanisms strongly conserved in evolution, invertebrates have recently emerged as a powerful new model in addiction research. In crayfish natural reward has proven surprisingly sensitive to human drugs of abuse, opening an unlikely avenue of research into the basic biological mechanisms of drug addiction. In a series of studies we first examined the presence of natural reward systems in crayfish, then characterized its sensitivity to a wide range of human drugs of abuse. A conditioned place preference (CPP) paradigm was used to demonstrate that crayfish seek out those environments that had previously been paired with the psychostimulants cocaine and amphetamine, and the opioid morphine. The administration of amphetamine exerted its effects at a number of sites, including the stimulation of circuits for active exploratory behaviors (i.e., SEEKING). A further study examined morphine-induced reward, extinction and reinstatement in crayfish. Repeated intra-circulatory infusions of morphine served as a reward when paired with distinct visual or tactile cues. Morphine-induced CPP was extinguished after repeated saline injections. Following this extinction phase, morphine-experienced crayfish were once again challenged with the drug. The priming injections of morphine reinstated CPP at all tested doses, suggesting that morphine-induced CPP is unrelenting. In an exploration of drug-associated behavioral sensitization in crayfish we concurrently mapped measures of locomotion and rewarding properties of morphine. Single and repeated intra-circulatory infusions of morphine resulted in persistent locomotory sensitization, even 5 days following the infusion. Moreover, a single dose of morphine was sufficient to induce long-term behavioral sensitization. CPP for morphine and context-dependent cues could not be disrupted over a drug free period of 5

The potential for using red claw crayfish and hybrid African catfish as biological control agents for Schistosoma host snails

NARCIS (Netherlands)

Monde, C.; Syampungani, S.; Rico, A.; Brink, van den P.J.

2017-01-01

The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After

Sylvatic plague vaccine and management of prairie dogs

Science.gov (United States)

Rocke, Tonie E.

2012-01-01

Scientists at the USGS National Wildlife Health Center (NWHC), in collaboration with colleagues at the University of Wisconsin (UW), have developed a sylvatic plague vaccine that shows great promise in protecting prairie dogs against plague (Mencher and others, 2004; Rocke and others, 2010). Four species of prairie dogs reside in the United States and Canada, and all are highly susceptible to plague and regularly experience outbreaks with devastating losses. Along with habitat loss and poisoning, plague has contributed to a significant historical decline in prairie dog populations. By some estimates, prairie dogs now occupy only 1 to 2 percent of their former range (Proctor and others, 2006), with prairie dog colonies being now much smaller and fragmented than they were historically, making individual colonies more vulnerable to elimination by plague (Antolin and others, 2002). At least one species, the Utah prairie dog (Cynomys parvidens) is listed by the U.S. Fish and Wildlife Service (FWS) as "threatened." Controlling plague is a vital concern for ongoing management and conservation efforts for prairie dogs. Current efforts to halt the spread of plague in prairie dog colonies typically rely on dusting individual prairie dog burrows with pesticides to kill plague-infected fleas. Although flea-control insecticides, such as deltamethrin, are useful in stopping plague outbreaks in these prairie dog colonies, dusting of burrows is labor intensive and time consuming and may affect other insects and arthropods. As an alternative approach, NWHC and UW scientists developed a sylvatic plague vaccine (SPV) for prairie dogs that can be delivered via oral bait. Laboratory studies have shown that consumption of this vaccine-laden bait by different prairie dog species results in significant protection against plague infection that can last for at least 9 months (Rocke and others, 2010; Rocke, unpublished). Work has now shifted to optimizing baits and distribution methods for

Plague in Iran: its history and current status

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Abdolrazagh Hashemi Shahraki

2016-07-01

Full Text Available OBJECTIVES: Plague remains a public health concern worldwide, particularly in old foci. Multiple epidemics of this disease have been recorded throughout the history of Iran. Despite the long-standing history of human plague in Iran, it remains difficult to obtain an accurate overview of the history and current status of plague in Iran. METHODS: In this review, available data and reports on cases and outbreaks of human plague in the past and present in Iran and in neighboring countries were collected, and information was compiled regarding when, where, and how many cases occurred. RESULTS: This paper considers the history of plague in Persia (the predecessor of today’s Iran and has a brief review of plague in countries in the World Health Organization Eastern Mediterranean Region, including a range of countries in the Middle East and North Africa. CONCLUSIONS: Since Iran has experienced outbreaks of plague for several centuries, neighboring countries have reported the disease in recent years, the disease can be silent for decades, and the circulation of Yersinia pestis has been reported among rodents and dogs in western Iran, more attention should be paid to disease monitoring in areas with previously reported human cases and in high-risk regions with previous epizootic and enzootic activity.

Plague in Iran: its history and current status.

Science.gov (United States)

Hashemi Shahraki, Abdolrazagh; Carniel, Elizabeth; Mostafavi, Ehsan

2016-01-01

Plague remains a public health concern worldwide, particularly in old foci. Multiple epidemics of this disease have been recorded throughout the history of Iran. Despite the long-standing history of human plague in Iran, it remains difficult to obtain an accurate overview of the history and current status of plague in Iran. In this review, available data and reports on cases and outbreaks of human plague in the past and present in Iran and in neighboring countries were collected, and information was compiled regarding when, where, and how many cases occurred. This paper considers the history of plague in Persia (the predecessor of today's Iran) and has a brief review of plague in countries in the World Health Organization Eastern Mediterranean Region, including a range of countries in the Middle East and North Africa. Since Iran has experienced outbreaks of plague for several centuries, neighboring countries have reported the disease in recent years, the disease can be silent for decades, and the circulation of Yersinia pestis has been reported among rodents and dogs in western Iran, more attention should be paid to disease monitoring in areas with previously reported human cases and in high-risk regions with previous epizootic and enzootic activity.

Can heat waves change the trophic role of the world's most invasive crayfish? Diet shifts in Procambarus clarkii.

Science.gov (United States)

Carreira, Bruno M; Segurado, Pedro; Laurila, Anssi; Rebelo, Rui

2017-01-01

In the Mediterranean basin, the globally increasing temperatures are expected to be accompanied by longer heat waves. Commonly assumed to benefit cold-limited invasive alien species, these climatic changes may also change their feeding preferences, especially in the case of omnivorous ectotherms. We investigated heat wave effects on diet choice, growth and energy reserves in the invasive red swamp crayfish, Procambarus clarkii. In laboratory experiments, we fed juvenile and adult crayfish on animal, plant or mixed diets and exposed them to a short or a long heat wave. We then measured crayfish survival, growth, body reserves and Fulton's condition index. Diet choices of the crayfish maintained on the mixed diet were estimated using stable isotopes (13C and 15N). The results suggest a decreased efficiency of carnivorous diets at higher temperatures, as juveniles fed on the animal diet were unable to maintain high growth rates in the long heat wave; and a decreased efficiency of herbivorous diets at lower temperatures, as juveniles in the cold accumulated less body reserves when fed on the plant diet. Heat wave treatments increased the assimilation of plant material, especially in juveniles, allowing them to sustain high growth rates in the long heat wave. Contrary to our expectations, crayfish performance decreased in the long heat wave, suggesting that Mediterranean summer heat waves may have negative effects on P. clarkii and that they are unlikely to boost its populations in this region. Although uncertain, it is possible that the greater assimilation of the plant diet resulted from changes in crayfish feeding preferences, raising the hypotheses that i) heat waves may change the predominant impacts of this keystone species and ii) that by altering species' trophic niches, climate change may alter the main impacts of invasive alien species.

Can heat waves change the trophic role of the world's most invasive crayfish? Diet shifts in Procambarus clarkii.

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Bruno M Carreira

Full Text Available In the Mediterranean basin, the globally increasing temperatures are expected to be accompanied by longer heat waves. Commonly assumed to benefit cold-limited invasive alien species, these climatic changes may also change their feeding preferences, especially in the case of omnivorous ectotherms. We investigated heat wave effects on diet choice, growth and energy reserves in the invasive red swamp crayfish, Procambarus clarkii. In laboratory experiments, we fed juvenile and adult crayfish on animal, plant or mixed diets and exposed them to a short or a long heat wave. We then measured crayfish survival, growth, body reserves and Fulton's condition index. Diet choices of the crayfish maintained on the mixed diet were estimated using stable isotopes (13C and 15N. The results suggest a decreased efficiency of carnivorous diets at higher temperatures, as juveniles fed on the animal diet were unable to maintain high growth rates in the long heat wave; and a decreased efficiency of herbivorous diets at lower temperatures, as juveniles in the cold accumulated less body reserves when fed on the plant diet. Heat wave treatments increased the assimilation of plant material, especially in juveniles, allowing them to sustain high growth rates in the long heat wave. Contrary to our expectations, crayfish performance decreased in the long heat wave, suggesting that Mediterranean summer heat waves may have negative effects on P. clarkii and that they are unlikely to boost its populations in this region. Although uncertain, it is possible that the greater assimilation of the plant diet resulted from changes in crayfish feeding preferences, raising the hypotheses that i heat waves may change the predominant impacts of this keystone species and ii that by altering species' trophic niches, climate change may alter the main impacts of invasive alien species.

COMPARISON AMONG PRE-GELATINIZED STARCHES OF DIFFERENT BOTANICAL ORIGINS USED IN NOBLE CRAYFISH ASTACUS ASTACUS DIETS

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D’AGARO E.

2006-01-01

Full Text Available The objective of the present experiment was to compare the biological value and the binding functionality of four pre-gelatinized starches (wheat, diet 1; waxy maize, diet 2; maize, diet 3 and potato, diet 4 used in crayfish diets. 360 juvenile of A. astacus (initial b.w.: 0.70 ± 0.15 g were cultured in 12 tanks for 43d. Growth performance were significantly higher in crayfish fed diets containing wheat and waxy maize compared to those containing maize and potato pre-gelatinized starches. Disintegration in water and shear force tests of diets confirmed the superior binding capability of pre-gelatinized starches obtained from wheat and waxy maize. These results suggest that the pregelatinized wheat and waxy maize starches are the best choice for the production of diets for the noble crayfish.

Small mammals distribution and diversity in a plague endemic area ...

African Journals Online (AJOL)

Small mammals play a role in plague transmission as hosts in all plague endemic areas. Information on distribution and diversity of small mammals is therefore important for plague surveillance and control in such areas. The objective of this study was to investigate small mammals' diversity and their distribution in plague ...

Conservation status of crayfishes of the United States and Canada

Science.gov (United States)

Christopher A. Taylor; Melvin L. Warren; J. F. Fitzpatrick; Horton H. Hobbs; Raymond F. Jezerinac; William L. Pflieger; Henry W. Robinson

1996-01-01

The American Fisheries Society (AFS) Endangered Species Committee herein provides a list of all crayfishes (families and Cambaridae) in the United States and Canada that includes state provincial distributions; a comprehensive review of the conservation status of all taxa; and references on biology, conservation, and...

Potential impacts of alien freshwater crayfish in South Africa | de ...

African Journals Online (AJOL)

The habitat preferences and life history characteristics of four alien species of freshwater crayfish (Cherax tenuimanus, C. destructor, C. quadricarinatus and Procambarus clarkii) are reviewed. The potential impact of these species on South African freshwater ecosystems is assessed and the desirability of allowing their ...

Where does human plague still persist in Latin America?

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Maria Cristina Schneider

2014-02-01

Full Text Available Plague is an epidemic-prone disease with a potential impact on public health, international trade, and tourism. It may emerge and re-emerge after decades of epidemiological silence. Today, in Latin America, human cases and foci are present in Bolivia, Brazil, Ecuador, and Peru.The objective of this study is to identify where cases of human plague still persist in Latin America and map areas that may be at risk for emergence or re-emergence. This analysis will provide evidence-based information for countries to prioritize areas for intervention.Evidence of the presence of plague was demonstrated using existing official information from WHO, PAHO, and Ministries of Health. A geo-referenced database was created to map the historical presence of plague by country between the first registered case in 1899 and 2012. Areas where plague still persists were mapped at the second level of the political/administrative divisions (counties. Selected demographic, socioeconomic, and environmental variables were described.Plague was found to be present for one or more years in 14 out of 25 countries in Latin America (1899-2012. Foci persisted in six countries, two of which have no report of current cases. There is evidence that human cases of plague still persist in 18 counties. Demographic and poverty patterns were observed in 11/18 counties. Four types of biomes are most commonly found. 12/18 have an average altitude higher than 1,300 meters above sea level.Even though human plague cases are very localized, the risk is present, and unexpected outbreaks could occur. Countries need to make the final push to eliminate plague as a public health problem for the Americas. A further disaggregated risk evaluation is recommended, including identification of foci and possible interactions among areas where plague could emerge or re-emerge. A closer geographical approach and environmental characterization are suggested.

Where does human plague still persist in Latin America?

Science.gov (United States)

Schneider, Maria Cristina; Najera, Patricia; Aldighieri, Sylvain; Galan, Deise I; Bertherat, Eric; Ruiz, Alfonso; Dumit, Elsy; Gabastou, Jean Marc; Espinal, Marcos A

2014-02-01

Plague is an epidemic-prone disease with a potential impact on public health, international trade, and tourism. It may emerge and re-emerge after decades of epidemiological silence. Today, in Latin America, human cases and foci are present in Bolivia, Brazil, Ecuador, and Peru. The objective of this study is to identify where cases of human plague still persist in Latin America and map areas that may be at risk for emergence or re-emergence. This analysis will provide evidence-based information for countries to prioritize areas for intervention. Evidence of the presence of plague was demonstrated using existing official information from WHO, PAHO, and Ministries of Health. A geo-referenced database was created to map the historical presence of plague by country between the first registered case in 1899 and 2012. Areas where plague still persists were mapped at the second level of the political/administrative divisions (counties). Selected demographic, socioeconomic, and environmental variables were described. Plague was found to be present for one or more years in 14 out of 25 countries in Latin America (1899-2012). Foci persisted in six countries, two of which have no report of current cases. There is evidence that human cases of plague still persist in 18 counties. Demographic and poverty patterns were observed in 11/18 counties. Four types of biomes are most commonly found. 12/18 have an average altitude higher than 1,300 meters above sea level. Even though human plague cases are very localized, the risk is present, and unexpected outbreaks could occur. Countries need to make the final push to eliminate plague as a public health problem for the Americas. A further disaggregated risk evaluation is recommended, including identification of foci and possible interactions among areas where plague could emerge or re-emerge. A closer geographical approach and environmental characterization are suggested.

Knowledge and practices related to plague in an endemic area of Uganda

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Kiersten J. Kugeler

2017-11-01

Full Text Available Background: Plague is a virulent zoonosis reported most commonly from Sub-Saharan Africa. Early treatment with antibiotics is important to prevent mortality. Understanding knowledge gaps and common behaviors informs the development of educational efforts to reduce plague mortality. Methods: A multi-stage cluster-sampled survey of 420 households was conducted in the plague-endemic West Nile region of Uganda to assess knowledge of symptoms and causes of plague and health care-seeking practices. Results: Most (84% respondents were able to correctly describe plague symptoms; approximately 75% linked plague with fleas and dead rats. Most respondents indicated that they would seek health care at a clinic for possible plague; however plague-like symptoms were reportedly common, and in practice, persons sought care for those symptoms at a health clinic infrequently. Conclusions: Persons in the plague-endemic region of Uganda have a high level of understanding of plague, yet topics for targeted educational messages are apparent. Keywords: Plague, Yersinia pestis, Knowledge, Practices, Behaviors, Africa

Fluoride bioaccumulation and toxic effects on the survival and behavior of the endangered white-clawed crayfish Austropotamobius pallipes (Lereboullet).

Science.gov (United States)

Aguirre-Sierra, Arantxa; Alonso, Alvaro; Camargo, Julio A

2013-08-01

Laboratory experiments were performed to examine the toxic effects of fluoride (F(-)) on the survival and behavior of white-clawed crayfish (Austropotamobius pallipes). Body fluoride contents (bioaccumulation) of test crayfish were also examined. No significant differences between male and female crayfish regarding mortality, escape (tail-flip) response, and fluoride bioaccumulation were detected. For mortality, 48-, 72-, 96-, 120-, 144-, 168-, and 192-h median lethal concentrations (LC50) were estimated to be 93.0, 55.3, 42.7, 36.5, 32.9, 30.6, and 28.9 mg F(-)/l, respectively. For the escape response, 48-, 72-, 96-, 120-, 144-, 168- and 192-h median effective concentrations (EC50) were estimated to be 18.4, 11.1, 8.6, 7.4, 6.7, 6.2 and 5.9 mg F(-)/l, respectively. Average food consumption in test crayfish tended to decrease with increasing water fluoride concentration with a 192-h lowest-observed effect concentration of 10.7 mg F(-)/l. These results indicate that the escape response was the most sensitive end point to fluoride toxicity followed by food consumption and mortality. Fluoride bioaccumulation in test crayfish increased with increasing water fluoride concentration and exposure time. The exoskeleton accumulated more fluoride than muscle. A comparison of the obtained results with previous data for other freshwater invertebrates shows that white-clawed crayfish are relatively tolerant to fluoride toxicity. We conclude that fluoride pollution in freshwater ecosystems should not be viewed as an important risk factor contributing to the catastrophic decrease of A. pallipes in many European countries. Our results indicate that fluoride bioaccumulation in A. pallipes might be used as a bioindicator of fluoride pollution in freshwater ecosystems where it is present.

Plague metapopulation dynamics in a natural reservoir

DEFF Research Database (Denmark)

Davis, S; Klassovskiy, N; Ageyev, V

2007-01-01

The ecology of plague (Yersinia pestis infection) in its ancient foci in Central Asia remains poorly understood. We present field data from two sites in Kazakhstan where the great gerbil (Rhombomys opimus) is the major natural host. Family groups inhabit and defend burrow systems spaced throughout...... the landscape, such that the host population may be considered a metapopulation, with each occupied burrow system a subpopulation. We examine plague transmission within and between family groups and its effect on survival. Transmission of plague occurred disproportionately within family groups although not all...... gerbils became infected once plague entered a burrow system. There were no spatial patterns to suggest that family groups in close proximity to infected burrow systems were more at risk of infection than those far away. At one site, infection increased the chances of burrow-system extinction. Overall...

MANAGEMENT OF THE WHITE-CLAWED CRAYFISH (AUSTROPOTAMOBIUS PALLIPES IN WESTERN FRANCE: ABIOTIC AND BIOTIC FACTORS STUDY

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TROUILHE M. C.

2003-04-01

Full Text Available In France, the distribution of the white-clawed crayfish, Austropotamobius pallipes (Lereboullet, 1858, is restricted, fragmented and mainly located in headwaters. To preserve this indigenous species, it is necessary to characterize its ecological requirements (water and habitat quality. With this aim in view, a two-year study is being conducted in the Deux-Sèvres department (Western France since November 2002. Nine brooks from four different catchments are monitored regularly; eight of the nine brooks harbour whiteclawed crayfish populations. Two sampling sites are surveyed per brook, the first being where the crayfish population is located and the second 2 to 3 km downstream. Physicochemical parameters (18 are measured twice monthly and biotic factors are estimated twice yearly. In this study, the I.B.G.N. (Indice Biologique Global Normalisé protocol based on the determination of macroinvertebrates was used as a biotic index of biological water quality. Results of this preliminary study on two brooks (Thouet and Verdonnière show that physico-chemical and biological data considered separately do not provide reliable information about A. pallipes ecological requirements. However, the use of multivariate analyses (Principal Component Analysis to combine abiotic and biotic factors highlights a good correlation between these parameters. Organic matter appears to be a better discriminating factor than mineral matter affecting presence or absence of the whiteclawed crayfish.

Trapping for invasive crayfish: comparisons of efficacy and selectivity of baited traps versus novel artificial refuge traps

Directory of Open Access Journals (Sweden)

Green Nicky

2018-01-01

Full Text Available Non-native crayfish can dominate the invertebrate biomass of invaded freshwaters, with their high ecological impacts resulting in their populations being controlled by numerous methods, especially trapping. Although baited funnel traps (BTs are commonly used, they tend to be selective in mainly catching large-bodied males. Here, the efficacy and selectivity of BTs were tested against an alternative trapping method based on artificial refuges (ARTs that comprised of a metal base with several tubes (refuges attached. The target species was signal crayfish Pacifastacus leniusculus in an upland river in southwest England. Trapping was completed in April to October over two consecutive years. In total, 5897 crayfish were captured, with 87% captured in ARTs. Comparison of the catch per unit effort (CPUE between the trapping methods in the same 24 hour periods revealed significantly higher CPUE in ARTs than of BTs. ARTs fished for 6 consecutive days had higher catches than both methods over 24 hours. Whilst catches in BTs were significantly dominated by males (1.49M:1F, the sex ratio of catches in ARTs was 0.99M:1F. The mean carapace length of crayfish was also significantly larger in BTs (43.2 ± 0.6 mm than in ARTs (33.6 ± 0.2 mm. Thus, ARTs had higher CPUE over 24 hour and 6 day periods versus BTs and also captured a greater proportion of smaller and female individuals. These results indicate that when trapping methods are deployed for managing invasions, the use of ARTs removes substantial numbers of crayfish of both sexes and of varying body sizes.

Pneumonic Plague Transmission, Moramanga, Madagascar, 2015.

Science.gov (United States)

Ramasindrazana, Beza; Andrianaivoarimanana, Voahangy; Rakotondramanga, Jean Marius; Birdsell, Dawn N; Ratsitorahina, Maherisoa; Rajerison, Minoarisoa

2017-03-01

During a pneumonic plague outbreak in Moramanga, Madagascar, we identified 4 confirmed, 1 presumptive, and 9 suspected plague case-patients. Human-to-human transmission among close contacts was high (reproductive number 1.44) and the case fatality rate was 71%. Phylogenetic analysis showed that the Yersinia pestis isolates belonged to group q3, different from the previous outbreak.

Identification of Chinese plague foci from long-term epidemiological data

Science.gov (United States)

Ben-Ari, Tamara; Neerinckx, Simon; Agier, Lydiane; Cazelles, Bernard; Xu, Lei; Zhang, Zhibin; Fang, Xiye; Wang, Shuchun; Liu, Qiyong; Stenseth, Nils C.

2012-01-01

Carrying out statistical analysis over an extensive dataset of human plague reports in Chinese villages from 1772 to 1964, we identified plague endemic territories in China (i.e., plague foci). Analyses rely on (i) a clustering method that groups time series based on their time-frequency resemblances and (ii) an ecological niche model that helps identify plague suitable territories characterized by value ranges for a set of predefined environmental variables. Results from both statistical tools indicate the existence of two disconnected plague territories corresponding to Northern and Southern China. Altogether, at least four well defined independent foci are identified. Their contours compare favorably with field observations. Potential and limitations of inferring plague foci and dynamics using epidemiological data is discussed. PMID:22570501

Empirical assessment of a threshold model for sylvatic plague

DEFF Research Database (Denmark)

Davis, Stephen; Leirs, Herwig; Viljugrein, H.

2007-01-01

Plague surveillance programmes established in Kazakhstan, Central Asia, during the previous century, have generated large plague archives that have been used to parameterize an abundance threshold model for sylvatic plague in great gerbil (Rhombomys opimus) populations. Here, we assess the model...... examine six hypotheses that could explain the resulting false positive predictions, namely (i) including end-of-outbreak data erroneously lowers the estimated threshold, (ii) too few gerbils were tested, (iii) plague becomes locally extinct, (iv) the abundance of fleas was too low, (v) the climate...

Burrowing Owls, Pulex irritans, and Plague.

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Belthoff, James R; Bernhardt, Scott A; Ball, Christopher L; Gregg, Michael; Johnson, David H; Ketterling, Rachel; Price, Emily; Tinker, Juliette K

2015-09-01

Western Burrowing Owls (Athene cunicularia hypugaea) are small, ground-dwelling owls of western North America that frequent prairie dog (Cynomys spp.) towns and other grasslands. Because they rely on rodent prey and occupy burrows once or concurrently inhabited by fossorial mammals, the owls often harbor fleas. We examined the potential role of fleas found on burrowing owls in plague dynamics by evaluating prevalence of Yersinia pestis in fleas collected from burrowing owls and in owl blood. During 2012-2013, fleas and blood were collected from burrowing owls in portions of five states with endemic plague-Idaho, Oregon, Washington, Colorado, and South Dakota. Fleas were enumerated, taxonomically identified, pooled by nest, and assayed for Y. pestis using culturing and molecular (PCR) approaches. Owl blood underwent serological analysis for plague antibodies and nested PCR for detection of Y. pestis. Of more than 4750 fleas collected from owls, Pulex irritans, a known plague vector in portions of its range, comprised more than 99.4%. However, diagnostic tests for Y. pestis of flea pools (culturing and PCR) and owl blood (PCR and serology) were negative. Thus, even though fleas were prevalent on burrowing owls and the potential for a relationship with burrowing owls as a phoretic host of infected fleas exists, we found no evidence of Y. pestis in sampled fleas or in owls that harbored them. We suggest that studies similar to those reported here during plague epizootics will be especially useful for confirming these results.

A review of plague persistence with special emphasis on fleas

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Wimsatt, Jeffrey; Biggins, Dean E.

2009-01-01

Sylvatic plague is highly prevalent during infrequent epizootics that ravage the landscape of western North America. During these periods, plague dissemination is very efficient. Epizootics end when rodent and flea populations are decimated and vectored transmission declines. A second phase (enzootic plague) ensues when plague is difficult to detect from fleas, hosts or the environment, and presents less of a threat to public health.

Knowledge and practices related to plague in an endemic area of Uganda.

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Kugeler, Kiersten J; Apangu, Titus; Forrester, Joseph D; Griffith, Kevin S; Candini, Gordian; Abaru, Janet; Okoth, Jimmy F; Apio, Harriet; Ezama, Geoffrey; Okello, Robert; Brett, Meghan; Mead, Paul

2017-11-01

Plague is a virulent zoonosis reported most commonly from Sub-Saharan Africa. Early treatment with antibiotics is important to prevent mortality. Understanding knowledge gaps and common behaviors informs the development of educational efforts to reduce plague mortality. A multi-stage cluster-sampled survey of 420 households was conducted in the plague-endemic West Nile region of Uganda to assess knowledge of symptoms and causes of plague and health care-seeking practices. Most (84%) respondents were able to correctly describe plague symptoms; approximately 75% linked plague with fleas and dead rats. Most respondents indicated that they would seek health care at a clinic for possible plague; however plague-like symptoms were reportedly common, and in practice, persons sought care for those symptoms at a health clinic infrequently. Persons in the plague-endemic region of Uganda have a high level of understanding of plague, yet topics for targeted educational messages are apparent. Published by Elsevier Ltd.

Laboratory and field assessment of uranium trophic transfer efficiency in the crayfish Orconectes limosus fed the bivalve C. fluminea

International Nuclear Information System (INIS)

Simon, Olivier; Garnier-Laplace, Jacqueline

2005-01-01

At present, ecotoxicological information regarding the impact of natural uranium (U) on freshwater ecosystems via the trophic contamination route is scarce. We generated an experimental trophic food chain involving the prey species, Corbicula fluminea, and a predator, Orconectes limosus, for a 10-day and a 30-day feeding periods (food ration: one whole soft body/day/crayfish). We studied the efficiency of U trophic transfer and the distribution of U in the predator. During the test, we varied the quantity of dietary U (from beforehand contaminated bivalves at concentrations ranging from 0.9 ± 0.1 to 20.2 ± 9 μg/g fw provided to each crayfish over the 10 days) applying a daily feeding rate equal to 3.9 ± 0.8% fw. The efficiency of U trophic transfer from clams to crayfish varied between 1 and 13% depending on the prey exposure modalities. Accumulation of U was observed in the digestive gland but also in gills, in the muscle, and in the molt of the crayfish after trophic exposure treatments. Under high-level exposure conditions, the digestive gland was the main target-organ, however a significant accumulation was also observed in the stomach. With regard to low levels of trophic exposure, accumulation of U in gills, in the stomach, and in the digestive gland was of the same order of magnitude. Longer exposure period which incorporated a crayfish molt, resulted in a decrease of trophic transfer ratio and a modified U tissue distribution

DISTRIBUTION, RECENT MORTALITIES AND CONSERVATION MEASURES OF CRAYFISH IN HELLENIC FRESH WATERS

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KOUTRAKIS E.

2007-04-01

Full Text Available Freshwater crayfish are found in 20 out of 53 Prefectures of Greece (38% and they form isolated populations in relatively pristine water bodies. Three indigenous crayfish species (ICS occur in Greek waters: Astacus astacus, Astacus leptodactylus and Austropotamobius torrentium, as well as one non-indigenous crayfish species (NICS Pacifastacus leniusculus. Greece represents probably the most southern natural distribution limit for A. astacus and A. torrentium in the world. Concerning NICS, P. leniusculus was imported, at least in two cases, from Sweden and Germany during the early and late 1980’s respectively, in order to replace A. astacus stocks impoverished by human activities. Recently, Cherax quadricarinatus specimens have been seen in a restaurant’s aquarium and pet shop, raising fears about uncontrolled imports of alien pet species. During our 2004-2005 survey, we found that P. leniusculus established not only a thriving population in the artificial Lake Agra (Region of Central Macedonia, but also they co-occur with A. torrentium there. It is also suspected that A. astacus may co-occur there with these two species, as three large male specimens of A. astacus were caught in a creek close to the lake. Concerning A. leptodactylus, there are three sets of preserved samples from the River Evros (state border with Turkey in Thrace today, dated back to the 19th century, but no recent information about occurrence was available. But the accidental catch of six specimens of A. leptodactylus during May 2005 in that river re-documented the occurrence of the species. Finally, a deep-dwelling A. torrentium population with bluish legs was found to live in depths up to 7,800 meters inside the Aggitis Cave in northeastern Greece. There is a lot of work to be done on geographic distribution, population dynamics, genetics, reproduction, nutrition, diseases, and farming of crayfish species in Greece. Moreover, several actions should be undertaken to

Where Does Human Plague Still Persist in Latin America?

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Schneider, Maria Cristina; Najera, Patricia; Aldighieri, Sylvain; Galan, Deise I.; Bertherat, Eric; Ruiz, Alfonso; Dumit, Elsy; Gabastou, Jean Marc; Espinal, Marcos A.

2014-01-01

Background Plague is an epidemic-prone disease with a potential impact on public health, international trade, and tourism. It may emerge and re-emerge after decades of epidemiological silence. Today, in Latin America, human cases and foci are present in Bolivia, Brazil, Ecuador, and Peru. Aims The objective of this study is to identify where cases of human plague still persist in Latin America and map areas that may be at risk for emergence or re-emergence. This analysis will provide evidence-based information for countries to prioritize areas for intervention. Methods Evidence of the presence of plague was demonstrated using existing official information from WHO, PAHO, and Ministries of Health. A geo-referenced database was created to map the historical presence of plague by country between the first registered case in 1899 and 2012. Areas where plague still persists were mapped at the second level of the political/administrative divisions (counties). Selected demographic, socioeconomic, and environmental variables were described. Results Plague was found to be present for one or more years in 14 out of 25 countries in Latin America (1899–2012). Foci persisted in six countries, two of which have no report of current cases. There is evidence that human cases of plague still persist in 18 counties. Demographic and poverty patterns were observed in 11/18 counties. Four types of biomes are most commonly found. 12/18 have an average altitude higher than 1,300 meters above sea level. Discussion Even though human plague cases are very localized, the risk is present, and unexpected outbreaks could occur. Countries need to make the final push to eliminate plague as a public health problem for the Americas. A further disaggregated risk evaluation is recommended, including identification of foci and possible interactions among areas where plague could emerge or re-emerge. A closer geographical approach and environmental characterization are suggested. PMID:24516682

Habitat and co-occurrence of native and invasive crayfish in the Pacific Northwest, USA

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Pearl, Christopher A.; Adams, Michael J.; McCreary, Brome

2013-01-01

Biological invasions can have dramatic effects on freshwater ecosystems and introduced crayfish can be particularly impacting. We document crayfish distribution in three large hydrographic basins (Rogue, Umpqua, Willamette/Columbia) in the Pacific Northwest USA. We used occupancy analyses to investigate habitat relationships and evidence for displacement of native Pacifastacus leniusculus (Dana, 1852) by two invaders. We found invasive Procambarus clarkii (Girard, 1852), in 51 of 283 sites and in all three hydrographic basins. We found invasive Orconectes n. neglectus (Faxon, 1885) at 68% of sites in the Rogue basin and provide first documentation of their broad distribution in the Umpqua basin. We found P. clarkii in both lentic and lotic habitats, and it was positively associated with manmade sites. P. leniusculus was positively associated with lotic habitats and negatively related to manmade sites. In the Rogue and Umpqua basins, O. n. neglectus and P. leniusculus were similar in their habitat associations. We did not find a negative relationship in site occupancy between O. n. neglectus and P. leniusculus. Our data suggest that P. clarkii has potential to locally displace P. leniusculus. There is still time for preventive measures to limit the spread of the invasive crayfish in this region.

[Epidemics and risk factors of plague in Junggar Basin, Xinjiang Uygur Autonomous Region, 2007-2016].

Science.gov (United States)

Zhang, Y J; Wang, C; Luo, T; Guo, R; Meng, W W

2017-10-10

Objective: To explore the epidemic situation of animal plague in Junggar Basin natural plague foci. Methods: Data on epidemics of plague and on population involved, as well as results on antibodies and pathogens, were analyzed. Samples on animals and vectors were collected from 18 counties in Junggar Basin plague natural foci between 2007 and 2016. Results: The density of Rhombomys (R.) opimus was temporally fluctuant, from 2.1/hm(2) to 22.6/hm(2) respectively. However, the spatial distribution appeared asymmetrical, with the highest seen in Kelamayi and Wumuqi-midong counties, as 14.2/hm(2) and 13.0/hm(2) respectively. Rates of capture on nocturnal rodents were from 4.2 % to 10.1 % , with the highest rate as 10.1 % in 2014. Meriones meridianus appeared the dominant species in the nocturnal community of rodents, which accounted for 81.9 % . Regarding the spatial and temporal distributions, rates of R. opimus with fleas appeared fluctuant, with an average rate as 90.7 % and the average total flea index was 10.44. In flea community of R. opimus , Xenopsylla (X.) skrjabini was found the dominant species, popular in distribution and accounted for 47.8 % . The average rate of nocturnal rodents with flea was 20.2 % , with total flea index as 1.20 and the dominant fleas were X. conformis conformis and Nosopsyllus laeviceps . A total of 13 species with 9 087 serum samples from rodents were detected as having Y. pestis antibody by IHA, with 617 positive samples. Of them, the positive rate of having R. opimus appeared the highest (9.4 % ), followed by D. sagitta (1.1 % ). Spatially, two clustered areas were found, with one in the eastern Junggar Basin from Changji to Mulei county, with the antibody positive rates of R. opimus as 14.3 % . The other one was in the central area of Junggar Basin, including Kelamayi, Shawan and Wusu counties, with the antibody positive rate as 13.6 % . The prevalence of plague on R. opimus was fluctuant, with the lowest seen in 2008, with the

Plague dynamics are driven by climate variation

DEFF Research Database (Denmark)

Stenseth, Nils Chr.; Samia, Noelle I.; Viljugrein, Hildegunn

2006-01-01

The bacterium Yersinia pestis causes bubonic plague. In Central Asia, where human plague is still reported regularly, the bacterium is common in natural populations of great gerbils. By using field data from 1949-1995 and previously undescribed statistical techniques, we show that Y. pestis...

Crayfish Behavior: Observing Arthropods to Learn about Science & Scientific Inquiry

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Rop, Charles J.

2010-01-01

This is a set of animal behavior investigations in which students will practice scientific inquiry as they observe crayfish, ask questions, and discuss territoriality, social interactions, and other behaviors. In doing this, they hone their skills of observation, learn to record and analyze data, control for variables, write hypotheses, make…

REDUCING THE THREAT TO CONTROL INVASIVE SIGNAL CRAYFISH REDUCING: THE POTENTIAL USE OF PHEROMONES

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STEBBING P. D.

2003-04-01

Full Text Available The need for an effective method of controlling invasive species of crayfish is of utmost importance given the plight of Europe’s native crayfish species. Many techniques have been applied to the growing problem with little success. Pheromones have been used to control terrestrial insect pests for a number of years with many success stories. The concept of applying pheromone control methods to the aquatic environment is by no means new, but has not been previously developed. This paper discusses the preliminary results from field trials testing traps baited with Pacifastacus leniusculus pheromones, and the potential application of the pheromones in controlling P. leniusculus populations.

Resistance to plague among black-tailed prairie dog populations

Science.gov (United States)

Rocke, Tonie E.; Williamson, Judy; Cobble, Kacy R.; Busch, Joseph D.; Antolin, Michael F.; Wagner, David M.

2012-01-01

In some rodent species frequently exposed to plague outbreaks caused by Yersinia pestis, resistance to the disease has evolved as a population trait. As a first step in determining if plague resistance has developed in black-tailed prairie dogs (Cynomys ludovicianus), animals captured from colonies in a plague-free region (South Dakota) and two plague-endemic regions (Colorado and Texas) were challenged with Y. pestis at one of three doses (2.5, 250, or 2500 mouse LD50s). South Dakota prairie dogs were far more susceptible to plague than Colorado and Texas prairie dogs (pdogs were quite similar in their response, with overall survival rates of 50% and 60%, respectively. Prairie dogs from these states were heterogenous in their response, with some animals dying at the lowest dose (37% and 20%, respectively) and some surviving even at the highest dose (29% and 40%, respectively). Microsatellite analysis revealed that all three groups were distinct genetically, but further studies are needed to establish a genetic basis for the observed differences in plague resistance.

[The plague in Finland in 1710].

Science.gov (United States)

Engström, N G

1994-01-01

In the autumn of 1710 Helsinki was struck by the so-called oriental plague during four months. The infection was transferred by black rats which harboured fleas. The flea-bites caused boils. It was believed that the plague was air-borne, and the air was very humid that autumn. Big fires were lit in order to reduce the humidity, the purpose being to make it easier for the infected to breathe. Attempts were also made to dissect the boils. The carriers of the contamination came as refugees from Estland over the Gulf of Finland. The infection had spread from Turkey to Poland and Balticum after the defeat of the Finnish-Swedish army in the summer of 1709 at Poltava in Ucraine. Helsingfors (Helsinki) was struck extremely hard. About two-thirds of the inhabitants died of the pestilence. Some escaped by fleeing to the countryside. The plague spread through the country as far north as to Uleåborg (Oulu) and Cajana (Kajaani). Marketplaces became important centres of infection. With the advent of the frost in December the plague dwindled. At that time Helsinki was practically a dead town.

[Monitoring the Microtus fuscus plague epidemic in Sichuan province during 2000 - 2008.

DEFF Research Database (Denmark)

Wang, Li-Mao; Song, Xiao-Yu; Zhu, Xiao-Ping

2009-01-01

OBJECTIVE: To analyze the epidemic tendency of Microtus fuscus plague during 2000 - 2008 in Sichuan province. METHODS: To investigate the plague each year according to "overall Plan of the Plague in the Whole Nation" and "Surveillance Program of Sichuan Province Plague". RESULTS: There were plague...... of fleas, Callopsylla sparsilis, Amphipsylla tutua tutua and Rhadinopsylla dahurica vicina, with the overall infection rate as 0.054%. CONCLUSION: Plague among Microtus fuscus showed a continuous epidemic in Sichuan province during 2000 - 2008....

Electrophysiological Investigation of Different Methods of Anesthesia in Lobster and Crayfish

Science.gov (United States)

Fregin, Torsten; Bickmeyer, Ulf

2016-01-01

Objectives In search for methods of anesthesia of crustaceans, an implanted electrode into lobster and crayfish CNS enabled us to monitor signal propagation in the nerve system of animals undergoing different protocols. Results Cooling (tap water 0°C, sea water -1,8°C) and anesthesia with MgCl2 (10%) were both discarded as anesthetic procedures because responses to external stimuli were still detectable under treatment. Contrarily, bubbling the aquarium water with CO2 can be considered a “partially successful” anesthesia, because signal propagation is inhibited but before that the animals show discomfort. The procedure of “electro-stunning” induces epileptic-form seizures in the crustacean CNS (lobster, crayfish), which overlay but do not mitigate the response to external stimuli. After several minutes the activity declines before the nervous system starts to recover. A feasible way to sacrifice lobsters is to slowly raise the water temperature (1°C min-1), as all electrical activities in the CNS cease at temperatures above ~30°C, whereas below this temperature the animals do not show signs of stress or escape behavior (e.g. tail flips) in the warming water. Conclusion CO2 is efficient to anaesthetize lobster and crayfish but due to low pH in water is stressful to the animals previous to anesthesia. Electrical stunning induces epileptiform seizures but paralyses the animals and leads to a reversible decline of nerve system activity after seizure. Electric stunning or slowly warming just before preparation may meet ethical expectations regarding anaesthesia and to sacrifice crustaceans. PMID:27642755

Plague in Uganda

Centers for Disease Control (CDC) Podcasts

2018-01-25

Dr. Paul Mead, a medical officer at CDC, discusses his article on Plague in Uganda.  Created: 1/25/2018 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 1/25/2018.

Human Plague Risk: Spatial-Temporal Models

Science.gov (United States)

Pinzon, Jorge E.

2010-01-01

This chpater reviews the use of spatial-temporal models in identifying potential risks of plague outbreaks into the human population. Using earth observations by satellites remote sensing there has been a systematic analysis and mapping of the close coupling between the vectors of the disease and climate variability. The overall result is that incidence of plague is correlated to positive El Nino/Southem Oscillation (ENSO).

Geographic distribution and ecological niche of plague in sub-Saharan Africa

DEFF Research Database (Denmark)

Neerinckx, Simon B; Peterson, Andrew T; Gulinck, Hubert

2008-01-01

Background Plague is a rapidly progressing, serious illness in humans that is likely to be fatal if not treated. It remains a public health threat, especially in sub-Saharan Africa. In spite of plague's highly focal nature, a thorough ecological understanding of the general distribution pattern...... of plague across sub-Saharan Africa has not been established to date. In this study, we used human plague data from sub-Saharan Africa for 1970-2007 in an ecological niche modeling framework to explore the potential geographic distribution of plague and its ecological requirements across Africa. Results We...... predict a broad potential distributional area of plague occurrences across sub-Saharan Africa. General tests of model's transferability suggest that our model can anticipate the potential distribution of plague occurrences in Madagascar and northern Africa. However, generality and predictive ability tests...

Effects of chronic cocaine, morphine and methamphetamine on the mobility, immobility and stereotyped behaviors in crayfish.

Science.gov (United States)

Imeh-Nathaniel, Adebobola; Rincon, Natalia; Orfanakos, Vasiliki Bessie; Brechtel, Leanne; Wormack, Leah; Richardson, Erika; Huber, Robert; Nathaniel, Thomas I

2017-08-14

The worth of crayfish as a model system for studies of addiction was not previously recognized because a drug-reward phenomenon had not been documented in this model system. In our previous experiments, we demonstrate that the crayfish natural reward pathways are sensitive to human drugs of abuse. This finding supports crayfish as a suitable model to characterize specific behaviors that are relevant in drug addiction research, and the current study builds on our previous findings. The aim of the present study was to investigate unconditioned neurobehavioral effects of repeated treatment regimens using cocaine, morphine, and methamphetamine for three consecutive days. We analyzed mobility, immobility and characterized stereotypic behaviors following intracardial infusions of 2.0μg/g or 10.0μg/g doses of cocaine, morphine, and methamphetamine for three days. The results showed that systemic cocaine, morphine, and methamphetamine increased mobility at a low dose of 2.0μg/g more effectively than a high dose of 10.0μg/g, while simultaneously showing that the high dose exerted a more prominent effect in increasing immobility. Moreover, systemic cocaine, morphine, and methamphetamine injections have discerning effects towards a group of defined unconditioned stereotyped behavioral patterns associated with each drug, rather than a shared universal behavioral effect. These findings provide insight into the behavioral and pharmacological basis responsible for the unconditioned effects of these drugs in crayfish. Copyright © 2017. Published by Elsevier B.V.

New distributional records of the stygobitic crayfish Cambarus cryptodytes (Decapoda: Cambaridae) in the Floridan Aquifer System of southwestern Georgia

Science.gov (United States)

Fenolio, Dante B.; Niemiller, Matthew L.; Gluesenkamp, Andrew G.; Mckee, Anna; Taylor, Steven J.

2017-01-01

Cambarus cryptodytes (Dougherty Plain Cave Crayfish) is an obligate inhabitant of groundwater habitats (i.e., a stygobiont) with troglomorphic adaptations in the Floridan aquifer system of southwestern Georgia and adjacent Florida panhandle, particularly in the Dougherty Plain and Marianna Lowlands. Documented occurrences of Dougherty Plain Cave Crayfish are spatially distributed as 2 primary clusters separated by a region where few caves and springs have been documented; however, the paucity of humanly accessible karst features in this intermediate region has inhibited investigation of the species' distribution. To work around this constraint, we employed bottle traps to sample for Dougherty Plain Cave Crayfish and other groundwater fauna in 18 groundwater-monitoring wells that access the Floridan aquifer system in 10 counties in southwestern Georgia. We captured 32 Dougherty Plain Cave Crayfish in 9 wells in 8 counties between September 2014 and August 2015. We detected crayfish at depths ranging from 17.9 m to 40.6 m, and established new county records for Early, Miller, Mitchell, and Seminole counties in Georgia, increasing the number of occurrences in Georgia from 8 to 17 sites. In addition, a new US Geological Survey (USGS) Hydrologic Unit Code 8 (HUC8) watershed record was established for the Spring Creek watershed. These new records fill in the distribution gap between the 2 previously known clusters in Georgia and Jackson County, FL. Furthermore, this study demonstrates that deployment of bottle traps in groundwater-monitoring wells can be an effective approach to presence—absence surveys of stygobionts, especially in areas where surface access to groundwater is limited.

Neuromodulation of activity-dependent synaptic enhancement at crayfish neuromuscular junction.

Science.gov (United States)

Qian, S M; Delaney, K R

1997-10-17

Action potential-evoked transmitter release is enhanced for many seconds after moderate-frequency stimulation (e.g. 15 Hz for 30 s) at the excitor motorneuron synapse of the crayfish dactyl opener muscle. Beginning about 1.5 s after a train, activity-dependent synaptic enhancement (ADSE) is dominated by a process termed augmentation (G.D. Bittner, D.A. Baxter, Synaptic plasticity at crayfish neuromuscular junctions: facilitation and augmentation, Synapse 7 (1991) 235-243'[4]; K.L. Magleby, Short-term changes in synaptic efficacy, in: G.M. Edelman, L.E. Gall, C.W. Maxwell (Eds.), Synaptic Function, John Wiley and Sons, New York, 1987, pp. 21-56; K.L. Magleby; J.E. Zengel, Augmentation: a process that acts to increase transmitter release at the frog neuromuscular junction, J. Physiol. (Lond.) 257 (1976) 449-470) which decays approximately exponentially with a time constant of about 10 s at 16 degrees C, reflecting the removal of Ca2+ which accumulates during the train in presynaptic terminals (K.R. Delaney, D.W. Tank, R.S. Zucker, Serotonin-mediated enhancement of transmission at crayfish neuromuscular junction is independent of changes in calcium, J. Neurosci. 11 (1991) 2631-2643). Serotonin (5-HT, 1 microM) increases evoked and spontaneous transmitter release several-fold (D. Dixon, H.L. Atwood, Crayfish motor nerve terminal's response to serotonin examined by intracellular microelectrode, J. Neurobiol. 16 (1985) 409-424; J. Dudel, Modulation of quantal synaptic release by serotonin and forskolin in crayfish motor nerve terminals, in: Modulation of Synaptic Transmission and Plasticity in Nervous Systems, G. Hertting, H.-C. Spatz (Eds.), Springer-Verlag, Berlin, 1988; S. Glusman, E.A. Kravitz. The action of serotonin on excitatory nerve terminals in lobster nerve-muscle preparations, J. Physiol. (Lond.) 325 (1982) 223-241). We found that ADSE persists about 2-3 times longer after moderate-frequency presynaptic stimulation in the presence of 5-HT. This slowing of the

Plague: A Millenary Infectious Disease Reemerging in the XXI Century.

Science.gov (United States)

Grácio, A J Dos Santos; Grácio, Maria Amélia A

2017-01-01

Plague, in the Middle Ages known as Black Death, continues to occur at permanent foci in many countries, in Africa, Asia, South America, and even the USA. During the last years outbreaks were reported from at least 3 geographical areas, in all cases after tens of years without reported cases. The recent human plague outbreaks in Libya and Algeria suggest that climatic and other environmental changes in Northern Africa may be favourable for Y. pestis epidemiologic cycle. If so, other Northern Africa countries with plague foci also may be at risk for outbreaks in the near future. It is important to remember that the danger of plague reoccurrence is not limited to the known natural foci, for example, those of Algeria, Angola, and Madagascar. In a general context, it is important that governments know the dangerous impact that this disease may have and that the health and medical community be familiar with the epidemiology, symptoms, treatment, and control of plague, so an appropriated and timely response can be delivered should the worst case happen. Plague can be used as a potential agent of bioterrorism. We have concluded that plague is without a doubt a reemerging infectious disease.

Ecology of Yersinia pestis and the Epidemiology of Plague.

Science.gov (United States)

Dubyanskiy, Vladimir M; Yeszhanov, Aidyn B

2016-01-01

This chapter summarizes information about the natural foci of plague in the world. We describe the location, main hosts, and vectors of Yersinia pestis. The ecological features of the hosts and vectors of plague are listed, including predators - birds and mammals and their role in the epizootic. The epizootic process in plague and the factors affecting the dynamics of epizootic activity of natural foci of Y. pestis are described in detail. The mathematical models of the epizootic process in plague and predictive models are briefly described. The most comprehensive list of the hosts and vectors of Y. pestis in the world is presented as well.

Inhalational Gentamicin Treatment Is Effective Against Pneumonic Plague in a Mouse Model

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David Gur

2018-04-01

treatment against this rapidly progressing infectious disease. We suggest the inhalational administration route as a clinically relevant treatment modality against pneumonic plague and other respiratory bacterial pathogens.

Stress reaction in crayfish: chlorides help to withstand stress in high nitrite concentration conditions – preliminary study

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Kozák P.

2011-06-01

Full Text Available A non-invasive method of recording cardiac activity (heart rate – HR and stress reaction (stress index – SI was used to understand the immediate and ongoing stress reaction of crayfish to the chemical stimuli. This method detects changes in the shape and amplitude parameters of the response to the stress factors, which characterized the crayfish functional state. Experimental animals (Astacus leptodactylus were divided to the two groups with (400 mg·L-1 Cl− and without added chlorides and then exposed to a stepwise increased level of nitrite to the final (sublethal-lethal concentration of 60 mg·L-1 N-NO\\hbox{$_{2}^{-}$}−2 within 24 hours. The course of crayfish reaction was evident and provided information about their reaction to the sublethal-lethal concentration over time. As expected, a less prominent stress reaction was detected in the group with chlorides. The non-invasive method successfully evaluated the sensing of chemical stimuli in water through HR and SI changes.

Evaluation of different marking methods for spiny-cheek crayfish (Orconectes limosus

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Buřič M.

2008-10-01

Full Text Available Different methods of marking were evaluated for Orconectes limosus (CL = carapace length, 12–37 mm under laboratory conditions: the use of passive integrated transponders, visible implant elastomers, visible implant alphanumeric tags, and cauterization. High survival (> 90% was obtained with all methods tested. Tag retention and readability were evaluated immediately after marking, before and after ecdysis, with moult increments and number of moults been recorded. Marking using cauterization negatively affects the percent moult increment (PMI of crayfish. The average PMI of 15 ± 0.88% did not differ between males (15 ± 1.41 mm and females (15 ± 1.12 mm. It was found that PMI gradually decreased with an increase in CL. Sixty-one moults were observed, with 12 crayfish (6 juveniles and 6 adults presenting two moults. Time between moults varied from 3 to 7 weeks. CL was increased with over 28 ± 2.68% due to two moults. Three females moulted twice after successful hatching and carrying of juveniles.

Plague in Yosemite

Centers for Disease Control (CDC) Podcasts

2017-03-23

Dr. Vicki Kramer, with the California Department of Public Health, discusses two cases of plague in Yosemite National Park.  Created: 3/23/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 3/23/2017.

Wild felids as hosts for human plague, Western United States

Science.gov (United States)

Bevins, S.N.; Tracey, J.A.; Franklin, S.P.; Schmit, V.L.; MacMillan, M.L.; Gage, K.L.; Schriefer, M.E.; Logan, K.A.; Sweanor, L.L.; Alldredge, M.W.; Krumm, C.; Boyce, W.M.; Vickers, W.; Riley, S.P.D.; Lyren, L.M.; Boydston, E.E.; Fisher, R.N.; Roelke, M.E.; Salman, M.; Crooks, K.R.; VandeWoude, S.

2009-01-01

Plague seroprevalence was estimated in populations pumas and bobcats in the western United States. High levels of exposure in plague-endemic regions indicate the need to consider the ecology and pathobiology of plague nondomestic felid hosts to better understand the role of these species in disease persistence and transmission.

Influence of human activity patterns on epidemiology of plague in ...

African Journals Online (AJOL)

Human plague has been a recurring public health threat in some villages in the Western Usambara Mountains, Tanzania, in the period between 1980 and 2004. Despite intensive past biological and medical research, the reasons for the plague outbreaks in the same set of villages remain unknown. Plague research needs ...

Effects of dietary propolis on the number and size of pleopadal egg, oxidative stress and antioxidant status of freshwater crayfish (Astacus leptodactylus Eschscholtz).

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Mişe Yonar, Serpil; Köprücü, Kenan; Yonar, Muhammet Enis; Silici, Sibel

2017-09-01

Four different crayfish diets; control, E1, E2 and E3, respectively containing 0, 1, 2 and 4% propolis, were tested to determine the effects of dietary propolis on the number and size of pleopadal egg, and malondialdehyde (MDA) level, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities in the freshwater crayfish (Astacus leptodactylus). The crayfish were kept at 9.6±5.3°C water temperature and fed three times daily during a six month period The pleopodal egg number (from 7 to 9) produced per gram of the body weight and total pleopodal egg number (from 201 to 263) significantly increased (Pegg size (from 3.22mm to 2.76mm). MDA level significantly (Pegg. The dietary propolis improves reproductive efficiency in the crayfish and decreases the oxidative stress under controlled hatchery conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Plague: A Millenary Infectious Disease Reemerging in the XXI Century

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A. J. dos Santos Grácio

2017-01-01

Full Text Available Plague, in the Middle Ages known as Black Death, continues to occur at permanent foci in many countries, in Africa, Asia, South America, and even the USA. During the last years outbreaks were reported from at least 3 geographical areas, in all cases after tens of years without reported cases. The recent human plague outbreaks in Libya and Algeria suggest that climatic and other environmental changes in Northern Africa may be favourable for Y. pestis epidemiologic cycle. If so, other Northern Africa countries with plague foci also may be at risk for outbreaks in the near future. It is important to remember that the danger of plague reoccurrence is not limited to the known natural foci, for example, those of Algeria, Angola, and Madagascar. In a general context, it is important that governments know the dangerous impact that this disease may have and that the health and medical community be familiar with the epidemiology, symptoms, treatment, and control of plague, so an appropriated and timely response can be delivered should the worst case happen. Plague can be used as a potential agent of bioterrorism. We have concluded that plague is without a doubt a reemerging infectious disease.

Differences found in the macroinvertebrate community composition in the presence or absence of the invasive alien crayfish, Orconectes hylas

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Freeland-Riggert, Brandye T.; Cairns, Stefan H.; Poulton, Barry C.; Riggert, Chris M.

2016-01-01

Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

Understanding the Persistence of Plague Foci in Madagascar

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Andrianaivoarimanana, Voahangy; Kreppel, Katharina; Elissa, Nohal; Duplantier, Jean-Marc; Carniel, Elisabeth; Rajerison, Minoarisoa; Jambou, Ronan

2013-01-01

Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar. PMID:24244760

[Advance to the research of the climate factor effect on the distribution of plague].

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Zhang, A P; Wei, R J; Xiong, H M; Wang, Z Y

2016-05-01

Plague is an anthropozoonotic disease caused by the Yersinia pestis ,which developed by many factors including local climate factors. In recent years, more and more studies on the effects of climate on plague were conducted. According to the researches, climate factors (mainly the rainfall and temperature) affected the development and distribution of plague by influencing the abundance of plague host animals and fleas index. The climate also affected the epidemic dynamics and the scope of plague. There were significant differences existing in the influence of climate on the palgue developed in the north and south China. In the two different plague epidemic systems, the solitary Daurian ground squirrel-flea-plague and the social Mongolian gerbil-flea-plague, the obvious population differences existed among the responses of the host animal to the climate changes. Although the internal relationship between the rainfall, the flea index, the density of rodents and the plague supported the nutritional cascade hypothesis, it can not prove that there is a clear causality between the occurrence of plague and rainfall. So the influence of climate factors on plague distribution can only be used for early forecasting and warning of the plague.

RNA-seq comparative analysis of Peking ducks spleen gene expression 24 h post-infected with duck plague virulent or attenuated virus.

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Liu, Tian; Cheng, Anchun; Wang, Mingshu; Jia, Renyong; Yang, Qiao; Wu, Ying; Sun, Kunfeng; Zhu, Dekang; Chen, Shun; Liu, Mafeng; Zhao, XinXin; Chen, Xiaoyue

2017-09-13

Duck plague virus (DPV), a member of alphaherpesvirus sub-family, can cause significant economic losses on duck farms in China. DPV Chinese virulent strain (CHv) is highly pathogenic and could induce massive ducks death. Attenuated DPV vaccines (CHa) have been put into service against duck plague with billions of doses in China each year. Researches on DPV have been development for many years, however, a comprehensive understanding of molecular mechanisms underlying pathogenicity of CHv strain and protection of CHa strain to ducks is still blank. In present study, we performed RNA-seq technology to analyze transcriptome profiling of duck spleens for the first time to identify differentially expressed genes (DEGs) associated with the infection of CHv and CHa at 24 h. Comparison of gene expression with mock ducks revealed 748 DEGs and 484 DEGs after CHv and CHa infection, respectively. Gene pathway analysis of DEGs highlighted valuable biological processes involved in host immune response, cell apoptosis and viral invasion. Genes expressed in those pathways were different in CHv infected duck spleens and CHa vaccinated duck spleens. The results may provide valuable information for us to explore the reasons of pathogenicity caused by CHv strain and protection activated by CHa strain.

Plague in Arab Maghreb, 1940-2015: a review

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Maliya Alia Malek

2016-06-01

Full Text Available We reviewed the epidemiology of 49 plague outbreaks which resulted in about 7,612 cases in 30 localities in the Arabic Maghreb (Mauritania, Morocco, Algeria, Tunisia, Libya and Egypt over 75 years. Between 1940 and 1950, most cases recorded in Morocco (75% and Egypt (20%, resulted from plague imported to Mediterranean harbours and transmitted by rat ectoparasites. In contrast, the re-emergence of plague in the southern part of Western Sahara in 1953 and in northeast Libya in 1976, was traced to direct contact between nomadic populations and infected goats and camels in natural foci, including the consumption of contaminated meat, illustrating this neglected oral route of contamination. Further familial outbreaks were traced to human ectoparasite transmission. Efforts to identify the factors contributing to natural foci may guide where to focus the surveillance of sentinel animals in order to eradicate human plague, if not Y. pestis from the Arab Maghreb.

The climatic context of major plague outbreaks in late medieval England

Science.gov (United States)

Pribyl, Kathleen

2017-04-01

The climatological triggers of major plague outbreaks in late medieval and early modern Europe remain unclear; recent studies have been inconclusive. Plague is primarily a rodent disease and due to the involvement of rodent hosts and insect vectors, the epidemiology of plague is complicated, but research on outbreaks in the Third Pandemic, which began in the late nineteenth century, has shown that in central and eastern Asia plague is linked to specific meteorological conditions. The disease adapts to a varied spectrum of ecological and climatological settings, which influence the development of plague waves, and due to Europe's geographical diversity, this paper focuses on one region, England, in its search for meteorological parameters contributing to plague outbreaks. The study period of this paper is defined by the arrival of Yersinia pestis in the British Isles in 1348 and the end of the fifteenth century. During this time, England's population dynamics were mortality-driven due to recurrent epidemic disease; and public health measures, such as quarantining, had not yet been introduced, hence the influence of social factors on the formation of major plague waves was very limited. The geographical and temporal focus of this study allows for the combination of the series of English major plague outbreaks, verified in the original texts, with the high-quality climate reconstructions based on both documentary sources and proxy data available for this region. The detailed analysis of the mechanisms contributing to English plague waves presented in this paper, reveals a complex interplay of time-lag responses and concurrent conditions involving temperature and precipitation parameters.

Red Plague Control Plan (RPCP)

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Cooke, Robert W.

2010-01-01

SCOPE: Prescribes the minimum requirements for the control of cuprous / cupric oxide corrosion (a.k.a. Red Plague) of silver-coated copper wire, cable, and harness assemblies. PURPOSE: Targeted for applications where exposure to assembly processes, environmental conditions, and contamination may promote the development of cuprous / cupric oxide corrosion (a.k.a. Red Plague) in silver-coated copper wire, cable, and harness assemblies. Does not exclude any alternate or contractor-proprietary documents or processes that meet or exceed the baseline of requirements established by this document. Use of alternate or contractor-proprietary documents or processes shall require review and prior approval of the procuring NASA activity.

Successful plague control in Namibia | Shangula | South African ...

African Journals Online (AJOL)

Objective. To demonstrate that plague can be successfully controlled. Design. A descriptive study outlining patterns of plague occurrence in relation to variables such as age group, gender, place and time. Setting. Two northern districts, namely Engela in Ohangwena region and Onandjokwe in Oshikoto region, an area of 2 ...

Travel history key to picking up on signs of bubonic plague.

Science.gov (United States)

2015-11-01

Health officials note an uptick in cases of bubonic plague in the United States this year, with at least 12 reported human cases reported since April 1. The CDC notes that healthcare providers should consider plague in patients who have traveled to plague-endemic areas and exhibit fever, headache, chills, weakness, and one or more swollen or tender and painful lymph nodes, referred to as buboes. Officials note that the disease rarely passes from person to person, but that this is a concern with patients who have developed the pneumonic form of the disease. Health officials note that in recent years there has been an average of seven cases of human plague each year in the United States, and that most of these cases are the bubonic form of the illness. Four patients confirmed to have plague this year have died, including the most recent case, a Utah man in his 70s. Most cases of plague in the United States occur in two regions. The first includes northern New Mexico, northern Arizona, and southern Colorado, and the second includes California, southern Oregon, and far western Nevada. When plague is suspected, treatment with antibiotics should begin immediately.

Impact of the Pla protease substrate α2-antiplasmin on the progression of primary pneumonic plague.

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Eddy, Justin L; Schroeder, Jay A; Zimbler, Daniel L; Bellows, Lauren E; Lathem, Wyndham W

2015-12-01

Many pathogens usurp the host hemostatic system during infection to promote pathogenesis. Yersinia pestis, the causative agent of plague, expresses the plasminogen activator protease Pla, which has been shown in vitro to target and cleave multiple proteins within the fibrinolytic pathway, including the plasmin inhibitor α2-antiplasmin (A2AP). It is not known, however, if Pla inactivates A2AP in vivo; the role of A2AP during respiratory Y. pestis infection is not known either. Here, we show that Y. pestis does not appreciably cleave A2AP in a Pla-dependent manner in the lungs during experimental pneumonic plague. Furthermore, following intranasal infection with Y. pestis, A2AP-deficient mice exhibit no difference in survival time, bacterial burden in the lungs, or dissemination from wild-type mice. Instead, we found that in the absence of Pla, A2AP contributes to the control of the pulmonary inflammatory response during infection by reducing neutrophil recruitment and cytokine production, resulting in altered immunopathology of the lungs compared to A2AP-deficient mice. Thus, our data demonstrate that A2AP is not significantly affected by the Pla protease during pneumonic plague, and although A2AP participates in immune modulation in the lungs, it has limited impact on the course or ultimate outcome of the infection. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Circadian rhythm in melatonin release as a mechanism to reinforce the temporal organization of the circadian system in crayfish.

Science.gov (United States)

Mendoza-Vargas, Leonor; Báez-Saldaña, Armida; Alvarado, Ramón; Fuentes-Pardo, Beatriz; Flores-Soto, Edgar; Solís-Chagoyán, Héctor

2017-06-01

Melatonin (MEL) is a conserved molecule with respect to its synthesis pathway and functions. In crayfish, MEL content in eyestalks (Ey) increases at night under the photoperiod, and this indoleamine synchronizes the circadian rhythm of electroretinogram amplitude, which is expressed by retinas and controlled by the cerebroid ganglion (CG). The aim of this study was to determine whether MEL content in eyestalks and CG or circulating MEL in hemolymph (He) follows a circadian rhythm under a free-running condition; in addition, it was tested whether MEL might directly influence the spontaneous electrical activity of the CG. Crayfish were maintained under constant darkness and temperature, a condition suitable for studying the intrinsic properties of circadian systems. MEL was quantified in samples obtained from He, Ey, and CG by means of an enzyme-linked immunosorbent assay, and the effect of exogenous MEL on CG spontaneous activity was evaluated by electrophysiological recording. Variation of MEL content in He, Ey, and CG followed a circadian rhythm that peaked at the same circadian time (CT). In addition, a single dose of MEL injected into the crayfish at different CTs reduced the level of spontaneous electrical activity in the CG. Results suggest that the circadian increase in MEL content directly affects the CG, reducing its spontaneous electrical activity, and that MEL might act as a periodical signal to reinforce the organization of the circadian system in crayfish.

Plague in Guinea Pigs and Its Prevention by Subunit Vaccines

Science.gov (United States)

Quenee, Lauriane E.; Ciletti, Nancy; Berube, Bryan; Krausz, Thomas; Elli, Derek; Hermanas, Timothy; Schneewind, Olaf

2011-01-01

Human pneumonic plague is a devastating and transmissible disease for which a Food and Drug Administration–approved vaccine is not available. Suitable animal models may be adopted as a surrogate for human plague to fulfill regulatory requirements for vaccine efficacy testing. To develop an alternative to pneumonic plague in nonhuman primates, we explored guinea pigs as a model system. On intranasal instillation of a fully virulent strain, Yersinia pestis CO92, guinea pigs developed lethal lung infections with hemorrhagic necrosis, massive bacterial replication in the respiratory system, and blood-borne dissemination to other organ systems. Expression of the Y. pestis F1 capsule was not required for the development of pulmonary infection; however, the capsule seemed to be important for the establishment of bubonic plague. The mean lethal dose (MLD) for pneumonic plague in guinea pigs was estimated to be 1000 colony-forming units. Immunization of guinea pigs with the recombinant forms of LcrV, a protein that resides at the tip of Yersinia type III secretion needles, or F1 capsule generated robust humoral immune responses. Whereas LcrV immunization resulted in partial protection against pneumonic plague challenge with 250 MLD Y. pestis CO92, immunization with recombinant F1 did not. rV10, a vaccine variant lacking LcrV residues 271-300, elicited protection against pneumonic plague, which seemed to be based on conformational antibodies directed against LcrV. PMID:21406168

Predicting probability of occurrence and factors affecting distribution and abundance of three Ozark endemic crayfish species at multiple spatial scales

Science.gov (United States)

Nolen, Matthew S.; Magoulick, Daniel D.; DiStefano, Robert J.; Imhoff, Emily M.; Wagner, Brian K.

2014-01-01

Crayfishes and other freshwater aquatic fauna are particularly at risk globally due to anthropogenic demand, manipulation and exploitation of freshwater resources and yet are often understudied. The Ozark faunal region of Missouri and Arkansas harbours a high level of aquatic biological diversity, especially in regard to endemic crayfishes. Three such endemics, Orconectes eupunctus,Orconectes marchandi and Cambarus hubbsi, are threatened by limited natural distribution and the invasions of Orconectes neglectus.

Hong Kong Junk: Plague and the Economy of Chinese Things.

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Peckham, Robert

2016-01-01

Histories of the Third Plague Pandemic, which diffused globally from China in the 1890s, have tended to focus on colonial efforts to regulate the movement of infected populations, on the state's draconian public health measures, and on the development of novel bacteriological theories of disease causation. In contrast, this article focuses on the plague epidemic in Hong Kong and examines colonial preoccupations with Chinese "things" as sources of likely contagion. In the 1890s, laboratory science invested plague with a new identity as an object to be collected, cultivated, and depicted in journals. At the same time, in the increasingly vociferous anti-opium discourse, opium was conceived as a contagious Chinese commodity: a plague. The article argues that rethinking responses to the plague through the history of material culture can further our understanding of the political consequences of disease's entanglement with economic and racial categories, while demonstrating the extent to which colonial agents "thought through things."

CONFIRMATION OF OCCURRENCE OF THE NARROW-CLAWED CRAYFISH ? STACUS LEPTODACTYLUS ESCHSCHOLTZ, 1823 IN THE RIVER EVROS IN GREECE

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PERDIKARIS C.

2007-04-01

Full Text Available The narrow-clawed crayfish Astacus leptodactylus Eschscholtz, 1823, is widely distributed in eastern European and western Asian countries. However, species presence in Greece was documented only by limited museum conserved specimens dating back to 1893. Recently (May 2005 several crayfish were captured in the Evros River (close to city of Didimotiho and these were identified as A. leptodactylus. The present work confirms the presence of A. leptodactylus in the Evros River still hundred and twelve years later and introduces the possibility of A. leptodactylus being indigenous to Greece.

Lovastatin protects against experimental plague in mice.

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Saravanan Ayyadurai

Full Text Available BACKGROUND: Plague is an ectoparasite-borne deadly infection caused by Yersinia pestis, a bacterium classified among the group A bioterrorism agents. Thousands of deaths are reported every year in some African countries. Tetracyclines and cotrimoxazole are used in the secondary prophylaxis of plague in the case of potential exposure to Y. pestis, but cotrimoxazole-resistant isolates have been reported. There is a need for additional prophylactic measures. We aimed to study the effectiveness of lovastatin, a cholesterol-lowering drug known to alleviate the symptoms of sepsis, for plague prophylaxis in an experimental model. METHODOLOGY: Lovastatin dissolved in Endolipide was intraperitoneally administered to mice (20 mg/kg every day for 6 days prior to a Y. pestis Orientalis biotype challenge. Non-challenged, lovastatin-treated and challenged, untreated mice were also used as control groups in the study. Body weight, physical behavior and death were recorded both prior to infection and for 10 days post-infection. Samples of the blood, lungs and spleen were collected from dead mice for direct microbiological examination, histopathology and culture. The potential antibiotic effect of lovastatin was tested on blood agar plates. CONCLUSIONS/SIGNIFICANCE: Lovastatin had no in-vitro antibiotic effect against Y. pestis. The difference in the mortality between control mice (11/15; 73.5% and lovastatin-treated mice (3/15; 20% was significant (P<0.004; Mantel-Haenszel test. Dead mice exhibited Y. pestis septicemia and inflammatory destruction of lung and spleen tissues not seen in lovastatin-treated surviving mice. These data suggest that lovastatin may help prevent the deadly effects of plague. Field observations are warranted to assess the role of lovastatin in the prophylaxis of human plague.

Nonlinear effect of climate on plague during the third pandemic in China

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Xu, Lei; Liu, Qiyong; Stige, Leif Chr.; Ben Ari, Tamara; Fang, Xiye; Chan, Kung-Sik; Wang, Shuchun; Stenseth, Nils Chr.; Zhang, Zhibin

2011-01-01

Over the years, plague has caused a large number of deaths worldwide and subsequently changed history, not the least during the period of the Black Death. Of the three plague pandemics, the third is believed to have originated in China. Using the spatial and temporal human plague records in China from 1850 to 1964, we investigated the association of human plague intensity (plague cases per year) with proxy data on climate condition (specifically an index for dryness/wetness). Our modeling analysis demonstrates that the responses of plague intensity to dry/wet conditions were different in northern and southern China. In northern China, plague intensity generally increased when wetness increased, for both the current and the previous year, except for low intensity during extremely wet conditions in the current year (reflecting a dome-shaped response to current-year dryness/wetness). In southern China, plague intensity generally decreased when wetness increased, except for high intensity during extremely wet conditions of the current year. These opposite effects are likely related to the different climates and rodent communities in the two parts of China: In northern China (arid climate), rodents are expected to respond positively to high precipitation, whereas in southern China (humid climate), high precipitation is likely to have a negative effect. Our results suggest that associations between human plague intensity and precipitation are nonlinear: positive in dry conditions, but negative in wet conditions. PMID:21646523

Potential corridors and barriers for plague spread in central Asia

Science.gov (United States)

2013-01-01

Background Plague (Yersinia pestis infection) is a vector-borne disease which caused millions of human deaths in the Middle Ages. The hosts of plague are mostly rodents, and the disease is spread by the fleas that feed on them. Currently, the disease still circulates amongst sylvatic rodent populations all over the world, including great gerbil (Rhombomys opimus) populations in Central Asia. Great gerbils are social desert rodents that live in family groups in burrows, which are visible on satellite images. In great gerbil populations an abundance threshold exists, above which plague can spread causing epizootics. The spatial distribution of the host species is thought to influence the plague dynamics, such as the direction of plague spread, however no detailed analysis exists on the possible functional or structural corridors and barriers that are present in this population and landscape. This study aims to fill that gap. Methods Three 20 by 20 km areas with known great gerbil burrow distributions were used to analyse the spatial distribution of the burrows. Object-based image analysis was used to map the landscape at several scales, and was linked to the burrow maps. A novel object-based method was developed – the mean neighbour absolute burrow density difference (MNABDD) – to identify the optimal scale and evaluate the efficacy of using landscape objects as opposed to square cells. Multiple regression using raster maps was used to identify the landscape-ecological variables that explain burrow density best. Functional corridors and barriers were mapped using burrow density thresholds. Cumulative resistance of the burrow distribution to potential disease spread was evaluated using cost distance analysis. A 46-year plague surveillance dataset was used to evaluate whether plague spread was radially symmetric. Results The burrow distribution was found to be non-random and negatively correlated with Greenness, especially in the floodplain areas. Corridors and

Complete Protection against Pneumonic and Bubonic Plague after a Single Oral Vaccination.

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Anne Derbise

Full Text Available No efficient vaccine against plague is currently available. We previously showed that a genetically attenuated Yersinia pseudotuberculosis producing the Yersinia pestis F1 antigen was an efficient live oral vaccine against pneumonic plague. This candidate vaccine however failed to confer full protection against bubonic plague and did not produce F1 stably.The caf operon encoding F1 was inserted into the chromosome of a genetically attenuated Y. pseudotuberculosis, yielding the VTnF1 strain, which stably produced the F1 capsule. Given orally to mice, VTnF1 persisted two weeks in the mouse gut and induced a high humoral response targeting both F1 and other Y. pestis antigens. The strong cellular response elicited was directed mostly against targets other than F1, but also against F1. It involved cells with a Th1-Th17 effector profile, producing IFNγ, IL-17, and IL-10. A single oral dose (108 CFU of VTnF1 conferred 100% protection against pneumonic plague using a high-dose challenge (3,300 LD50 caused by the fully virulent Y. pestis CO92. Moreover, vaccination protected 100% of mice from bubonic plague caused by a challenge with 100 LD50 Y. pestis and 93% against a high-dose infection (10,000 LD50. Protection involved fast-acting mechanisms controlling Y. pestis spread out of the injection site, and the protection provided was long-lasting, with 93% and 50% of mice surviving bubonic and pneumonic plague respectively, six months after vaccination. Vaccinated mice also survived bubonic and pneumonic plague caused by a high-dose of non-encapsulated (F1- Y. pestis.VTnF1 is an easy-to-produce, genetically stable plague vaccine candidate, providing a highly efficient and long-lasting protection against both bubonic and pneumonic plague caused by wild type or un-encapsulated (F1-negative Y. pestis. To our knowledge, VTnF1 is the only plague vaccine ever reported that could provide high and durable protection against the two forms of plague after a single

Complete Protection against Pneumonic and Bubonic Plague after a Single Oral Vaccination.

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Derbise, Anne; Hanada, Yuri; Khalifé, Manal; Carniel, Elisabeth; Demeure, Christian E

2015-01-01

No efficient vaccine against plague is currently available. We previously showed that a genetically attenuated Yersinia pseudotuberculosis producing the Yersinia pestis F1 antigen was an efficient live oral vaccine against pneumonic plague. This candidate vaccine however failed to confer full protection against bubonic plague and did not produce F1 stably. The caf operon encoding F1 was inserted into the chromosome of a genetically attenuated Y. pseudotuberculosis, yielding the VTnF1 strain, which stably produced the F1 capsule. Given orally to mice, VTnF1 persisted two weeks in the mouse gut and induced a high humoral response targeting both F1 and other Y. pestis antigens. The strong cellular response elicited was directed mostly against targets other than F1, but also against F1. It involved cells with a Th1-Th17 effector profile, producing IFNγ, IL-17, and IL-10. A single oral dose (108 CFU) of VTnF1 conferred 100% protection against pneumonic plague using a high-dose challenge (3,300 LD50) caused by the fully virulent Y. pestis CO92. Moreover, vaccination protected 100% of mice from bubonic plague caused by a challenge with 100 LD50 Y. pestis and 93% against a high-dose infection (10,000 LD50). Protection involved fast-acting mechanisms controlling Y. pestis spread out of the injection site, and the protection provided was long-lasting, with 93% and 50% of mice surviving bubonic and pneumonic plague respectively, six months after vaccination. Vaccinated mice also survived bubonic and pneumonic plague caused by a high-dose of non-encapsulated (F1-) Y. pestis. VTnF1 is an easy-to-produce, genetically stable plague vaccine candidate, providing a highly efficient and long-lasting protection against both bubonic and pneumonic plague caused by wild type or un-encapsulated (F1-negative) Y. pestis. To our knowledge, VTnF1 is the only plague vaccine ever reported that could provide high and durable protection against the two forms of plague after a single oral

Sylvatic plague vaccine: A new tool for conservation of threatened and endangered species?

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Abbott, Rachel C.; Osorio, Jorge E.; Bunck, Christine M.; Rocke, Tonie E.

2012-01-01

Plague, a disease caused by Yersinia pestis introduced into North America about 100 years ago, is devastating to prairie dogs and the highly endangered black-footed ferret. Current attempts to control plague in these species have historically relied on insecticidal dusting of prairie dog burrows to kill the fleas that spread the disease. Although successful in curtailing outbreaks in most instances, this method of plague control has significant limitations. Alternative approaches to plague management are being tested, including vaccination. Currently, all black-footed ferret kits released for reintroduction are vaccinated against plague with an injectable protein vaccine, and even wild-born kits are captured and vaccinated at some locations. In addition, a novel, virally vectored, oral vaccine to prevent plague in wild prairie dogs has been developed and will soon be tested as an alternative, preemptive management tool. If demonstrated to be successful, oral vaccination of selected prairie dog populations could decrease the occurrence of plague epizootics in key locations, thereby reducing the source of bacteria while avoiding the indiscriminate environmental effects of dusting. Just as rabies in wild carnivores has largely been controlled through an active surveillance and oral vaccination program, we believe an integrated plague management strategy would be similarly enhanced with the addition of a cost-effective, bait-delivered, sylvatic plague vaccine for prairie dogs. Control of plague in prairie dogs, and potentially other rodents, would significantly advance prairie dog conservation and black-footed ferret recovery.

EVALUATION OF THE AMERICAN WATERWEED (ELODEA CANADENSIS MICHX. AS SUPPLEMENTAL FOOD FOR THE NOBLE CRAYFISH, ASTACUS ASTACUS

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D’AGARO E.

2004-01-01

Full Text Available We conducted a preliminary study to evaluate the capacity of summerling Astacus astacus to consume the American waterweed (Elodea canadensis Michx..under artificial rearing conditions. Summerling A. astacus (initial b.w.: 0.32 ± 0.02 g were cultured (50 crayfish/m2 in 600l tanks for 89 days. The experimental design was composed of three treatments as follows: control diet (D (crude protein: 40.9% DM; ether extract: 7.4% DM, elodea (E (crude protein: 25.8% DM; ether extract: 1.4% DM and control diet + elodea (D + E with three replicates per treatment. Temperature, dissolved oxygen, and other water parameters were measured weekly (T: 20.1°C; O2: 7.2 mg/l; pH: 7.5; N-NH4: 0.05 mg/l; N-NO2: 0.01 mg/l; N-NO3: 29.9 mg/l. The relative growth rate was significantly (P < 0.01 higher in treatment D + E (195% and D (143% than in E (65%. The reduced growth observed in crayfish fed elodea only can probably be due to the lower dietary lipid level of the plant respect to the standard crayfish requirements. At the end of the experiment, the survival rate of A. astacus was higher (P < 0.05 for the treatment D + E (87% and D (81%, compared to E (56%. Our results suggest that E. canadensis can be used as a non-expensive supplemental food in order to increase growth and survival in summerling noble crayfish. They also showed that A. astacus has the potential to consume this macrophyte in nature.

Hfq-dependent, co-ordinate control of cyclic diguanylate synthesis and catabolism in the plague pathogen Yersinia pestis.

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Bellows, Lauren E; Koestler, Benjamin J; Karaba, Sara M; Waters, Christopher M; Lathem, Wyndham W

2012-11-01

Yersinia pestis, the cause of the disease plague, forms biofilms to enhance flea-to-mammal transmission. Biofilm formation is dependent on exopolysaccharide synthesis and is controlled by the intracellular levels of the second messenger molecule cyclic diguanylate (c-di-GMP), but the mechanisms by which Y. pestis regulates c-di-GMP synthesis and turnover are not fully understood. Here we show that the small RNA chaperone Hfq contributes to the regulation of c-di-GMP levels and biofilm formation by modulating the abundance of both the c-di-GMP phosphodiesterase HmsP and the diguanylate cyclase HmsT. To do so, Hfq co-ordinately promotes hmsP mRNA accumulation while simultaneously decreasing the stability of the hmsT transcript. Hfq-dependent regulation of HmsP occurs at the transcriptional level while the regulation of HmsT is post-transcriptional and is localized to the 5' untranslated region/proximal coding sequence of the hmsT transcript. Decoupling HmsP from Hfq-based regulation is sufficient to overcome the effects of Δhfq on c-di-GMP and biofilm formation. We propose that Y. pestis utilizes Hfq to link c-di-GMP levels to environmental conditions and that the disregulation of c-di-GMP turnover in the absence of Hfq may contribute to the severe attenuation of Y. pestis lacking this RNA chaperone in animal models of plague. © 2012 Blackwell Publishing Ltd.

The Use of Fresh Cogongrass as Transportation Media with Level Dry System for Broodstock of Crayfish on Various Old Time

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Ferdinand Hukama Taqwa

2015-01-01

Full Text Available The research was to determine the effect of the use of fresh cogongrass as media packaging filler on survival rate of broodstock of crayfish that transported with level dry system for 24, 48, dan 72 hours which randomized completely design experiment. The research preparation were media preparation of pond water, preparation of filler material and preparation of experimental animal (3 days adaptation after arrived from producer and starvation for 24 hours. The major research were anestetion of broodstock of crayfish with direct sock of low temperature at 12oC for ±5 minutes, transportation experiment of broodstock with fresh cogongrass as material filler. The result showed that the use of fresh cogongrass on various old time of dry level system has a significantly different to time of recovery and survival rate of broodstock of crayfish after tranforted. The fastest time of recovery was 89.55 seconds for 24 hours transportation and significantly different with time of transportation for 48 hours and 72 hours. The survival rate after tranported the highest was 98.89% for 24 hours transportation and significantly different with time of transportation for 48 hours and 72 hours. This research showed that the use of fresh cogongrass as material packaging filler of dry level system was still effective until 48 hours.Keywords: afresh cogongrass, broodstock of crayfish, various old time transportation, level dry system

Comparative Ultrastructure and Carbohydrate Composition of Gastroliths from Astacidae, Cambaridae and Parastacidae Freshwater Crayfish (Crustacea, Decapoda

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Gérard Alcaraz

2012-12-01

Full Text Available Crustaceans have to cyclically replace their rigid exoskeleton in order to grow. Most of them harden this skeleton by a calcification process. Some decapods (land crabs, lobsters and crayfish elaborate calcium storage structures as a reservoir of calcium ions in their stomach wall, as so-called gastroliths. For a better understanding of the cyclic elaboration of these calcium deposits, we studied the ultrastructure of gastroliths from freshwater crayfish by using a combination of microscopic and physical techniques. Because sugars are also molecules putatively involved in the elaboration process of these biomineralizations, we also determined their carbohydrate composition. This study was performed in a comparative perspective on crayfish species belonging to the infra-order Astacidea (Decapoda, Malacostraca: three species from the Astacoidea superfamily and one species from the Parastacoidea superfamily. We observed that all the gastroliths exhibit a similar dense network of protein-chitin fibers, from macro- to nanoscale, within which calcium is precipitated as amorphous calcium carbonate. Nevertheless, they are not very similar at the molecular level, notably as regards their carbohydrate composition. Besides glucosamine, the basic carbohydrate component of chitin, we evidenced the presence of other sugars, some of which are species-specific like rhamnose and galacturonic acid whereas xylose and mannose could be linked to proteoglycan components.

A non-stationary relationship between global climate phenomena and human plague incidence in Madagascar.

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Kreppel, Katharina S; Caminade, Cyril; Telfer, Sandra; Rajerison, Minoarison; Rahalison, Lila; Morse, Andy; Baylis, Matthew

2014-10-01

Plague, a zoonosis caused by Yersinia pestis, is found in Asia and the Americas, but predominantly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. Plague's occurrence is affected by local climate factors which in turn are influenced by large-scale climate phenomena such as the El Niño Southern Oscillation (ENSO). The effects of ENSO on regional climate are often enhanced or reduced by a second large-scale climate phenomenon, the Indian Ocean Dipole (IOD). It is known that ENSO and the IOD interact as drivers of disease. Yet the impacts of these phenomena in driving plague dynamics via their effect on regional climate, and specifically contributing to the foci of transmission on Madagascar, are unknown. Here we present the first analysis of the effects of ENSO and IOD on plague in Madagascar. We use a forty-eight year monthly time-series of reported human plague cases from 1960 to 2008. Using wavelet analysis, we show that over the last fifty years there have been complex non-stationary associations between ENSO/IOD and the dynamics of plague in Madagascar. We demonstrate that ENSO and IOD influence temperature in Madagascar and that temperature and plague cycles are associated. The effects on plague appear to be mediated more by temperature, but precipitation also undoubtedly influences plague in Madagascar. Our results confirm a relationship between plague anomalies and an increase in the intensity of ENSO events and precipitation. This work widens the understanding of how climate factors acting over different temporal scales can combine to drive local disease dynamics. Given the association of increasing ENSO strength and plague anomalies in Madagascar it may in future be possible to forecast plague outbreaks in Madagascar. The study gives insight into the complex and changing relationship between climate factors and plague in Madagascar.

A non-stationary relationship between global climate phenomena and human plague incidence in Madagascar.

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Katharina S Kreppel

2014-10-01

Full Text Available Plague, a zoonosis caused by Yersinia pestis, is found in Asia and the Americas, but predominantly in Africa, with the island of Madagascar reporting almost one third of human cases worldwide. Plague's occurrence is affected by local climate factors which in turn are influenced by large-scale climate phenomena such as the El Niño Southern Oscillation (ENSO. The effects of ENSO on regional climate are often enhanced or reduced by a second large-scale climate phenomenon, the Indian Ocean Dipole (IOD. It is known that ENSO and the IOD interact as drivers of disease. Yet the impacts of these phenomena in driving plague dynamics via their effect on regional climate, and specifically contributing to the foci of transmission on Madagascar, are unknown. Here we present the first analysis of the effects of ENSO and IOD on plague in Madagascar.We use a forty-eight year monthly time-series of reported human plague cases from 1960 to 2008. Using wavelet analysis, we show that over the last fifty years there have been complex non-stationary associations between ENSO/IOD and the dynamics of plague in Madagascar. We demonstrate that ENSO and IOD influence temperature in Madagascar and that temperature and plague cycles are associated. The effects on plague appear to be mediated more by temperature, but precipitation also undoubtedly influences plague in Madagascar. Our results confirm a relationship between plague anomalies and an increase in the intensity of ENSO events and precipitation.This work widens the understanding of how climate factors acting over different temporal scales can combine to drive local disease dynamics. Given the association of increasing ENSO strength and plague anomalies in Madagascar it may in future be possible to forecast plague outbreaks in Madagascar. The study gives insight into the complex and changing relationship between climate factors and plague in Madagascar.

Development of crayfish bio-based plastic materials processed by small-scale injection moulding.

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Felix, Manuel; Romero, Alberto; Cordobes, Felipe; Guerrero, Antonio

2015-03-15

Protein has been investigated as a source for biodegradable polymeric materials. This work evaluates the development of plastic materials based on crayfish and glycerol blends, processed by injection moulding, as a fully biodegradable alternative to conventional polymer-based plastics. The effect of different additives, namely sodium sulfite or bisulfite as reducing agents, urea as denaturing agent and L-cysteine as cross-linking agent, is also analysed. The incorporation of any additive always yields an increase in energy efficiency at the mixing stage, but its effect on the mechanical properties of the bioplastics is not so clear, and even dampened. The additive developing a greater effect is L-cysteine, showing higher Young's modulus values and exhibiting a remnant thermosetting potential. Thus, processing at higher temperature yields a remarkable increase in extensibility. This work illustrates the feasibility of crayfish-based green biodegradable plastics, thereby contributing to the search for potential value-added applications for this by-product. © 2014 Society of Chemical Industry.

A multigear protocol for sampling crayfish assemblages in Gulf of Mexico coastal streams

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William R. Budnick; William E. Kelso; Susan B. Adams; Michael D. Kaller

2018-01-01

Identifying an effective protocol for sampling crayfish in streams that vary in habitat and physical/chemical characteristics has proven problematic. We evaluated an active, combined-gear (backpack electrofishing and dipnetting) sampling protocol in 20 Coastal Plain streams in Louisiana. Using generalized linear models and rarefaction curves, we evaluated environmental...

Interactions between crayfish, benthic invertebrates, macrophyte roots and sediment in a littoral zone

Czech Academy of Sciences Publication Activity Database

Ságová-Marečková, Markéta

2002-01-01

Roč. 155, č. 4 (2002), s. 645-665 ISSN 0003-9136 Grant - others:GA the Center for Limnology of the UW-Madison(XX) BSR8514330 Institutional research plan: CEZ:AV0Z5020903 Keywords : predation * food * crayfish Subject RIV: EE - Microbiology, Virology Impact factor: 1.195, year: 2002

Human activity spaces and plague risks in three contrasting ...

African Journals Online (AJOL)

Since 1980 plague has been a human threat in the Western Usambara Mountains in Tanzania. However, the spatial-temporal pattern of plague occurrence remains poorly understood. The main objective of this study was to gain understanding of human activity patterns in relation to spatial distribution of fleas in Lushoto ...

Intranasal delivery of a protein subunit vaccine using a Tobacco Mosaic Virus platform protects against pneumonic plague.

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Arnaboldi, Paul M; Sambir, Mariya; D'Arco, Christina; Peters, Lauren A; Seegers, Jos F M L; Mayer, Lloyd; McCormick, Alison A; Dattwyler, Raymond J

2016-11-11

Yersinia pestis, one of history's deadliest pathogens, has killed millions over the course of human history. It has attributes that make it an ideal choice to produce mass casualties and is a prime candidate for use as a biological weapon. When aerosolized, Y. pestis causes pneumonic plague, a pneumonia that is 100% lethal if not promptly treated with effective antibiotics. Currently, there is no FDA approved plague vaccine. The current lead vaccine candidate, a parenterally administered protein subunit vaccine comprised of the Y. pestis virulence factors, F1 and LcrV, demonstrated variable levels of protection in primate pneumonic plague models. As the most likely mode of exposure in biological attack with Y. pestis is by aerosol, this raises a question of whether this parenteral vaccine will adequately protect humans against pneumonic plague. In the present study we evaluated two distinct mucosal delivery platforms for the intranasal (IN) administration of LcrV and F1 vaccine proteins, a live bacterial vector, Lactobacillus plantarum, and a Tobacco Mosaic Virus (TMV) based delivery platform. IN administration of L. plantarum expressing LcrV, or TMV-conjugated to LcrV and F1 (TMV-LcrV+TMV-F1) resulted in the similar induction of high titers of IgG antibodies and evidence of proinflammatory cytokine secretion. However, only the TMV-conjugate delivery platform protected against subsequent lethal challenge with Y. pestis. TMV-LcrV+TMV-F1 co-vaccinated mice had no discernable morbidity and no mortality, while mice vaccinated with L. plantarum expressing LcrV or rLcrV+rF1 without TMV succumbed to infection or were only partially protected. Thus, TMV is a suitable mucosal delivery platform for an F1-LcrV subunit vaccine that induces complete protection against pneumonic infection with a lethal dose of Y. pestis in mice. Copyright © 2016 Elsevier Ltd. All rights reserved.

[The plague: A disease that is still haunting our collective memory].

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Peiffer-Smadja, N; Thomas, M

2017-06-01

Although the plague has practically disappeared from Europe since the beginning of the 20th century, it is still present in everyone's memory. Owing to three pandemics, it has left an indelible mark on mankind and has given rise to many popular phrases, paintings, books or more recently movies and video games. After a brief description of the plague as a disease, we will try to trace the history of the plague through some of the works of art it inspired and then to show how the plague is still haunting our collective memory. Copyright © 2017 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Tritium uptake kinetics in crayfish (Orconectes immunis)

International Nuclear Information System (INIS)

Patrick, P.H.

1985-06-01

Uptake of tritiated water (HTO) by Orconectes immunis was investigated under laboratory conditions. Tritium uptake in the tissue-free water fraction (TFWT) was described using an exponential model. When steady-state was reached, the ratio of TFWT to HTO was approximately 0.9. Uptake of tritium in the organically-bound fraction (OBT) proceeded slowly, and had not reached steady-state after 117 days of culture. Although steady-state was never reached, the maximum observed ration of OBT to TFWT in whole animals was approximately 0.6. However, this ratio exceeded unity in the exoskeleton. Specific activity ratios of OBT between crayfish and lettuce (food source) were less than or at unity for various test conditions

A Field Study of Plague and Tularemia in Rodents, Western Iran.

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Mostafavi, Ehsan; Shahraki, Abdolrazagh Hashemi; Japoni-Nejad, Alireza; Esmaeili, Saber; Darvish, Jamshid; Sedaghat, Mohammad Mehdi; Mohammadi, Ali; Mohammadi, Zeinolabedin; Mahmoudi, Ahmad; Pourhossein, Behzad; Ghasemi, Ahmad; Gyuranecz, Miklós; Carniel, Elisabeth

2017-04-01

Kurdistan Province in Iran is a historical focus for plague and tularemia. This study aimed at assessing the current status of these two foci by studying their rodent reservoirs. Rodents were trapped and their ectoparasites were collected. The genus and species of both rodents and ectoparasites were determined. Serological analyses of rodent blood samples were done by enzyme-linked immunosorbent assay for plague and by standard tube agglutination assay for tularemia. Rodent spleen samples were subjected to bacterial culture, microscopic examination, and real-time PCR to search for active plague or tularemia infection. During this study, 245 rodents were trapped, of which the most abundant genera were Apodemus (40%), Mus (24.49%), and Meriones (12.65%). One hundred fifty-three fleas, 37 mites, and 54 ticks were collected on these rodents. The results of all direct and indirect tests were negative for plague. Serological tests were positive for tularemia in 4.8% of trapped rodents. This study is the first report on the presence of tularemia infection in rodents in Western Iran. Since Meriones persicus is a known reservoir for plague and tularemia, and this rodent carried plague and tularemia vectors in Marivan and Sanandaj districts, there is a real potential for the occurrence of these two diseases in this region.

Human anti-plague monoclonal antibodies protect mice from Yersinia pestis in a bubonic plague model.

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Xiaodong Xiao

2010-10-01

Full Text Available Yersinia pestis is the etiologic agent of plague that has killed more than 200 million people throughout the recorded history of mankind. Antibiotics may provide little immediate relief to patients who have a high bacteremia or to patients infected with an antibiotic resistant strain of plague. Two virulent factors of Y. pestis are the capsid F1 protein and the low-calcium response (Lcr V-protein or V-antigen that have been proven to be the targets for both active and passive immunization. There are mouse monoclonal antibodies (mAbs against the F1- and V-antigens that can passively protect mice in a murine model of plague; however, there are no anti-Yersinia pestis monoclonal antibodies available for prophylactic or therapeutic treatment in humans. We identified one anti-F1-specific human mAb (m252 and two anti-V-specific human mAb (m253, m254 by panning a naïve phage-displayed Fab library against the F1- and V-antigens. The Fabs were converted to IgG1s and their binding and protective activities were evaluated. M252 bound weakly to peptides located at the F1 N-terminus where a protective mouse anti-F1 mAb also binds. M253 bound strongly to a V-antigen peptide indicating a linear epitope; m254 did not bind to any peptide from a panel of 53 peptides suggesting that its epitope may be conformational. M252 showed better protection than m253 and m254 against a Y, pestis challenge in a plague mouse model. A synergistic effect was observed when the three antibodies were combined. Incomplete to complete protection was achieved when m252 was given at different times post-challenge. These antibodies can be further studied to determine their potential as therapeutics or prophylactics in Y. pestis infection in humans.

CRAYFISH PREDATION ON TADPOLES : A COMPARISON BETWEEN A NATIVE (AUSTROPOTAMOBIUS PALLIPES AND AN ALIEN SPECIES (PROCAMBARUS CLARKII.

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GHERARDI F.

2001-04-01

Full Text Available In the laboratory, the motivation and/or ability to prey on anuran larvae (Bufo bufo, Rana kl. esculenta and R. italica were compared between a native European (Austropotamobius pallipes and an alien North American crayfish species (Procambarus clarkii. Both were skilled predators of tadpoles, adopting a sit-and-wait strategy. However, because P. clarkii displayed lower latency times in the presence of one of the three amphibians (Rana kl. esculenta here tested, the hypothesis is raised that invasive crayfish are more opportunistic predators and possibly faster in switching to different prey than those species they are displacing. From a conservation perspective, these preliminary results further emphasise the importance of studies centred on the invasion-displacement dichotomy.

Stone crayfish in the Czech Republic: how does its population density depend on basic chemical and physical properties of water?

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Vlach P.

2013-03-01

Full Text Available The stone crayfish (Austropotamobius torrentium Schrank is one of the two native crayfish species in the Czech Republic. The populations as well as physical and chemical parameters of water (pH, conductivity, dissolved oxygen, undissolved particles, NH3, NH4+, NO2−, NO3−, phosphorus, Ca2+ and SO42 −  of 33 streams were examined to find the ecological plasticity of this crayfish and some relations between these parameters and population densities. The mentioned parameters often significantly varied at the sites. Two approaches were applied to find relations between these parameters and observed abundance. At first, the observed streams were compared using RDA (streams  ×  physical-chemical parameters. No significance was found while testing relationship between the streams grouped along the 1st axis of model and the observed abundances of stone crayfish. However, some correlations between abundance and conductivity, calcium, nitrates and sulphates were found using polynomial regression. These relationships are explicable in terms of mutual correlations, underlying geology and other factors which affect abundances. In conclusion, A. torrentium is able to inhabit waters with a large range of physical and chemical parameters of the water without any fundamental influence on population densities. Water properties play an indisputable role as limiting ecological factors at uncommon concentrations, but population densities are probably influenced much more by the types of habitats, habitat features, predation and other ecological factors.

EFFECTS OF RATION SIZE AND TEMPERATURE ON MOULT INCREMENT AND METABOLIC PARAMETERS OF JUVENILE NOBLE CRAYFISH, ASTACUS ASTACUS

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RENAI B.

2007-07-01

Full Text Available A laboratory experiment was carried out to test the combined effects of ration size (1 vs 3% body weight, b.w. and temperature (15 ± 2 vs 22 ± 2 °C on moult increment and metabolic parameters of 80 juvenile noble crayfish (Astacus astacus. The maximum daily consumption (Cmax and respiration rate (R were used to calculate the growth scope (i.e. the difference between maximum daily energy consumption and energy costs at a given temperature. The conversion of R into a food-equivalent unit allowed the comparison with Cmax. Results showed that crayfish obtained the maximum moult increment when fed 3% b.w. while temperature seemed to play a less relevant role on growth rate per moult, affecting only the moulting frequency. Crayfish A. astacus fed ad libitum showed a relative insensitivity to the metabolic parameters (oxygen uptake, R and Cmax within the analysed range of temperatures, possibly as a reflection of this “species” distribution across a broad variety of habitats with different thermal regimes. In the present study, A. astacus displayed characteristics proper of a K-selected species, as slow to moderate growth.

Investigating the genetic and epigenetic basis of big biological questions with the parthenogenetic marbled crayfish: A review and perspectives.

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Vogt, Gunter

2018-03-01

In the last 15 years, considerable attempts have been undertaken to develop the obligately parthenogenetic marbled crayfish Procambarus virginalis as a new model in biology. Its main advantage is the production of large numbers of offspring that are genetically identical to the mother, making this crustacean particularly suitable for research in epigenetics. Now, a draft genome, transcriptome and genome-wide methylome are available opening new windows for research. In this article, I summarize the biological advantages and genomic and epigenetic features of marbled crayfish and, based on first promising data, discuss what this new model could contribute to answering of ''big'' biological questions. Genome mining is expected to reveal new insights into the genetic specificities of decapod crustaceans, the genetic basis of arthropod reproduction, moulting and immunity, and more general topics such as the genetic underpinning of adaptation to fresh water, omnivory, biomineralization, sexual system change, behavioural variation, clonal genome evolution, and resistance to cancer. Epigenetic investigations with the marbled crayfish can help clarifying the role of epigenetic mechanisms in gene regulation, tissue specification, adult stem cell regulation, cell ageing, organ regeneration and disease susceptibility. Marbled crayfish is further suitable to elucidate the relationship between genetic and epigenetic variation, the transgenerational inheritance of epigenetic signatures and the contribution of epigenetic phenotype variation to the establishment of social hierarchies, environmental adaptation and speciation. These issues can be tackled by experiments with highly standardized laboratory lineages, comparison of differently adapted wild populations and the generation of genetically and epigenetically edited strains.

The Stone Age Plague and Its Persistence in Eurasia.

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Andrades Valtueña, Aida; Mittnik, Alissa; Key, Felix M; Haak, Wolfgang; Allmäe, Raili; Belinskij, Andrej; Daubaras, Mantas; Feldman, Michal; Jankauskas, Rimantas; Janković, Ivor; Massy, Ken; Novak, Mario; Pfrengle, Saskia; Reinhold, Sabine; Šlaus, Mario; Spyrou, Maria A; Szécsényi-Nagy, Anna; Tõrv, Mari; Hansen, Svend; Bos, Kirsten I; Stockhammer, Philipp W; Herbig, Alexander; Krause, Johannes

2017-12-04

Yersinia pestis, the etiologic agent of plague, is a bacterium associated with wild rodents and their fleas. Historically it was responsible for three pandemics: the Plague of Justinian in the 6 th century AD, which persisted until the 8 th century [1]; the renowned Black Death of the 14 th century [2, 3], with recurrent outbreaks until the 18 th century [4]; and the most recent 19 th century pandemic, in which Y. pestis spread worldwide [5] and became endemic in several regions [6]. The discovery of molecular signatures of Y. pestis in prehistoric Eurasian individuals and two genomes from Southern Siberia suggest that Y. pestis caused some form of disease in humans prior to the first historically documented pandemic [7]. Here, we present six new European Y. pestis genomes spanning the Late Neolithic to the Bronze Age (LNBA; 4,800 to 3,700 calibrated years before present). This time period is characterized by major transformative cultural and social changes that led to cross-European networks of contact and exchange [8, 9]. We show that all known LNBA strains form a single putatively extinct clade in the Y. pestis phylogeny. Interpreting our data within the context of recent ancient human genomic evidence that suggests an increase in human mobility during the LNBA, we propose a possible scenario for the early spread of Y. pestis: the pathogen may have entered Europe from Central Eurasia following an expansion of people from the steppe, persisted within Europe until the mid-Bronze Age, and moved back toward Central Eurasia in parallel with human populations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Plague: Infections of Companion Animals and Opportunities for Intervention

Directory of Open Access Journals (Sweden)

Petra C.F. Oyston

2011-06-01

Full Text Available Plague is a zoonotic disease, normally circulating in rodent populations, transmitted to humans most commonly through the bite of an infected flea vector. Secondary infection of the lungs results in generation of infectious aerosols, which pose a significant hazard to close contacts. In enzootic areas, plague infections have been reported in owners and veterinarians who come into contact with infected pets. Dogs are relatively resistant, but can import infected fleas into the home. Cats are acutely susceptible, and can present a direct hazard to health. Reducing roaming and hunting behaviours, combined with flea control measures go some way to reducing the risk to humans. Various vaccine formulations have been developed which may be suitable to protect companion animals from contracting plague, and thus preventing onward transmission to man. Since transmission has resulted in a number of fatal cases of plague, the vaccination of domestic animals such as cats would seem a low cost strategy for reducing the risk of infection by this serious disease in enzootic regions.

The effect of sensory feedback on crayfish posture and locomotion: II. Neuromechanical simulation of closing the loop.

Science.gov (United States)

Bacqué-Cazenave, Julien; Chung, Bryce; Cofer, David W; Cattaert, Daniel; Edwards, Donald H

2015-03-15

Neuromechanical simulation was used to determine whether proposed thoracic circuit mechanisms for the control of leg elevation and depression in crayfish could account for the responses of an experimental hybrid neuromechanical preparation when the proprioceptive feedback loop was open and closed. The hybrid neuromechanical preparation consisted of a computational model of the fifth crayfish leg driven in real time by the experimentally recorded activity of the levator and depressor (Lev/Dep) nerves of an in vitro preparation of the crayfish thoracic nerve cord. Up and down movements of the model leg evoked by motor nerve activity released and stretched the model coxobasal chordotonal organ (CBCO); variations in the CBCO length were used to drive identical variations in the length of the live CBCO in the in vitro preparation. CBCO afferent responses provided proprioceptive feedback to affect the thoracic motor output. Experiments performed with this hybrid neuromechanical preparation were simulated with a neuromechanical model in which a computational circuit model represented the relevant thoracic circuitry. Model simulations were able to reproduce the hybrid neuromechanical experimental results to show that proposed circuit mechanisms with sensory feedback could account for resistance reflexes displayed in the quiescent state and for reflex reversal and spontaneous Lev/Dep bursting seen in the active state. Copyright © 2015 the American Physiological Society.

Efficacy of Primate Humoral Passive Transfer in a Murine Model of Pneumonic Plague Is Mouse Strain-Dependent

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V. A. Graham

2014-01-01

Full Text Available New vaccines against biodefense-related and emerging pathogens are being prepared for licensure using the US Federal Drug Administration’s “Animal Rule.” This allows licensure of drugs and vaccines using protection data generated in animal models. A new acellular plague vaccine composed of two separate recombinant proteins (rF1 and rV has been developed and assessed for immunogenicity in humans. Using serum obtained from human volunteers immunised with various doses of this vaccine and from immunised cynomolgus macaques, we assessed the pharmacokinetic properties of human and cynomolgus macaque IgG in BALB/c and the NIH Swiss derived Hsd:NIHS mice, respectively. Using human and cynomolgus macaque serum with known ELISA antibody titres against both vaccine components, we have shown that passive immunisation of human and nonhuman primate serum provides a reproducible delay in median time to death in mice exposed to a lethal aerosol of plague. In addition, we have shown that Hsd:NIHS mice are a better model for humoral passive transfer studies than BALB/c mice.

Effects of temperature on the acute toxicity of heavy metals (Cr, Cd, and Hg) to the freshwater crayfish, Procambarus clarkii (Girard)

Energy Technology Data Exchange (ETDEWEB)

Del Ramo, J.; Diaz-Mayans, J.; Torreblanca, A.; Nunez, A.

1987-05-01

Chromium, an essential trace element for humans and animals is involved in normal carbohydrate metabolism; however, it is toxic at high concentrations. There is no evidence that cadmium and mercury are biologically essential but their toxicity for organisms is well known. Both cause toxic effects at low concentrations to most organisms, especially in combination with other environmental variables such as temperature. Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and waste waters in this area. In 1978, the American red crayfish Procambarus clarkii appeared in lake Albufera and in the surrounding rice fields. Without adequate sanitary control, the crayfish is presently being fished commercially for human consumption. The purpose of the present study is to evaluate the degree of toxicity of various heavy metals (chromium, cadmium and mercury) to freshwater crayfish Procambarus clarkii at various temperatures.

Roles of Chaperone/Usher Pathways of Yersinia pestis in a Murine Model of Plague and Adhesion to Host Cells

Science.gov (United States)

Hatkoff, Matthew; Runco, Lisa M.; Pujol, Celine; Jayatilaka, Indralatha; Furie, Martha B.; Bliska, James B.

2012-01-01

Yersinia pestis and many other Gram-negative pathogenic bacteria use the chaperone/usher (CU) pathway to assemble virulence-associated surface fibers termed pili or fimbriae. Y. pestis has two well-characterized CU pathways: the caf genes coding for the F1 capsule and the psa genes coding for the pH 6 antigen. The Y. pestis genome contains additional CU pathways that are capable of assembling pilus fibers, but the roles of these pathways in the pathogenesis of plague are not understood. We constructed deletion mutations in the usher genes for six of the additional Y. pestis CU pathways. The wild-type (WT) and usher deletion strains were compared in the murine bubonic (subcutaneous) and pneumonic (intranasal) plague infection models. Y. pestis strains containing deletions in CU pathways y0348-0352, y1858-1862, and y1869-1873 were attenuated for virulence compared to the WT strain by the intranasal, but not subcutaneous, routes of infection, suggesting specific roles for these pathways during pneumonic plague. We examined binding of the Y. pestis WT and usher deletion strains to A549 human lung epithelial cells, HEp-2 human cervical epithelial cells, and primary human and murine macrophages. Y. pestis CU pathways y0348-0352 and y1858-1862 were found to contribute to adhesion to all host cells tested, whereas pathway y1869-1873 was specific for binding to macrophages. The correlation between the virulence attenuation and host cell binding phenotypes of the usher deletion mutants identifies three of the additional CU pathways of Y. pestis as mediating interactions with host cells that are important for the pathogenesis of plague. PMID:22851745

Diverse Genotypes of Yersinia pestis Caused Plague in Madagascar in 2007.

Science.gov (United States)

Riehm, Julia M; Projahn, Michaela; Vogler, Amy J; Rajerison, Minoaerisoa; Andersen, Genevieve; Hall, Carina M; Zimmermann, Thomas; Soanandrasana, Rahelinirina; Andrianaivoarimanana, Voahangy; Straubinger, Reinhard K; Nottingham, Roxanne; Keim, Paul; Wagner, David M; Scholz, Holger C

2015-06-01

Yersinia pestis is the causative agent of human plague and is endemic in various African, Asian and American countries. In Madagascar, the disease represents a significant public health problem with hundreds of human cases a year. Unfortunately, poor infrastructure makes outbreak investigations challenging. DNA was extracted directly from 93 clinical samples from patients with a clinical diagnosis of plague in Madagascar in 2007. The extracted DNAs were then genotyped using three molecular genotyping methods, including, single nucleotide polymorphism (SNP) typing, multi-locus variable-number tandem repeat analysis (MLVA), and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) analysis. These methods provided increasing resolution, respectively. The results of these analyses revealed that, in 2007, ten molecular groups, two newly described here and eight previously identified, were responsible for causing human plague in geographically distinct areas of Madagascar. Plague in Madagascar is caused by numerous distinct types of Y. pestis. Genotyping method choice should be based upon the discriminatory power needed, expense, and available data for any desired comparisons. We conclude that genotyping should be a standard tool used in epidemiological investigations of plague outbreaks.

[Primary pneumonic plague with nosocomial transmission in La Libertad, Peru 2010].

Science.gov (United States)

Donaires, Luis F; Céspedes, Manuel; Valencia, Pedro; Salas, Juan Carlos; Luna, María E; Castañeda, Alex; Peralta, Víctor; Cabezas, César; Pachas, Paul E

2010-09-01

Pneumonic plague is one of the clinical forms of plague, of low frequency and high mortality, transmitted by direct inhalation of Yersinia pestis coming from an animal or from person to person. To describe the clinical and epidemiological characteristics of the cases of primary pneumonic plague in an outbreak in the north of Peru. The clinical records of the confirmed cases of primary pneumonic plague presenting in an outbreak occurring in La Libertad, in July 2010, were reviewed, also the search and contact investigation was performed. The index case was identified, as well as three additional cases, out of these, two were nosocomial infections related to the index case. The initial clinical presentation was characterized by sudden onset of fever, chills, myalgia and chest pain, which in less than 24 hours evolved to hypotension and cyanosis. The initiation of specific treatment varied from 2 to 12 days, and cases with prompt initiation of treatment had a better clinical outcome. The lethality was 50% (2/4). Nosocomial transmission of pneumonic plague in Peru is evidenced, with severe clinical manifestations and high lethality.

Epidemiological analysis of the Eyam plague outbreak of 1665-1666.

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Whittles, Lilith K; Didelot, Xavier

2016-05-11

Plague, caused by the bacterium Yersinia pestis, is one of the deadliest infectious diseases in human history, and still causes worrying outbreaks in Africa and South America. Despite the historical and current importance of plague, several questions remain unanswered concerning its transmission routes and infection risk factors. The plague outbreak that started in September 1665 in the Derbyshire village of Eyam claimed 257 lives over 14 months, wiping out entire families. Since previous attempts at modelling the Eyam plague, new data have been unearthed from parish records revealing a much more complete record of the disease. Using a stochastic compartmental model and Bayesian analytical methods, we found that both rodent-to-human and human-to-human transmission played an important role in spreading the infection, and that they accounted, respectively, for a quarter and three-quarters of all infections, with a statistically significant seasonality effect. We also found that the force of infection was stronger for infectious individuals living in the same household compared with the rest of the village. Poverty significantly increased the risk of disease, whereas adulthood decreased the risk. These results on the Eyam outbreak contribute to the current debate on the relative importance of plague transmission routes. © 2016 The Authors.

The trophic responses of two different rodent-vector-plague systems to climate change.

Science.gov (United States)

Xu, Lei; Schmid, Boris V; Liu, Jun; Si, Xiaoyan; Stenseth, Nils Chr; Zhang, Zhibin

2015-02-07

Plague, the causative agent of three devastating pandemics in history, is currently a re-emerging disease, probably due to climate change and other anthropogenic changes. Without understanding the response of plague systems to anthropogenic or climate changes in their trophic web, it is unfeasible to effectively predict years with high risks of plague outbreak, hampering our ability for effective prevention and control of the disease. Here, by using surveillance data, we apply structural equation modelling to reveal the drivers of plague prevalence in two very different rodent systems: those of the solitary Daurian ground squirrel and the social Mongolian gerbil. We show that plague prevalence in the Daurian ground squirrel is not detectably related to its trophic web, and that therefore surveillance efforts should focus on detecting plague directly in this ecosystem. On the other hand, plague in the Mongolian gerbil is strongly embedded in a complex, yet understandable trophic web of climate, vegetation, and rodent and flea densities, making the ecosystem suitable for more sophisticated low-cost surveillance practices, such as remote sensing. As for the trophic webs of the two rodent species, we find that increased vegetation is positively associated with higher temperatures and precipitation for both ecosystems. We furthermore find a positive association between vegetation and ground squirrel density, yet a negative association between vegetation and gerbil density. Our study thus shows how past surveillance records can be used to design and improve existing plague prevention and control measures, by tailoring them to individual plague foci. Such measures are indeed highly needed under present conditions with prevailing climate change. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

The trophic responses of two different rodent–vector–plague systems to climate change

Science.gov (United States)

Xu, Lei; Schmid, Boris V.; Liu, Jun; Si, Xiaoyan; Stenseth, Nils Chr.; Zhang, Zhibin

2015-01-01

Plague, the causative agent of three devastating pandemics in history, is currently a re-emerging disease, probably due to climate change and other anthropogenic changes. Without understanding the response of plague systems to anthropogenic or climate changes in their trophic web, it is unfeasible to effectively predict years with high risks of plague outbreak, hampering our ability for effective prevention and control of the disease. Here, by using surveillance data, we apply structural equation modelling to reveal the drivers of plague prevalence in two very different rodent systems: those of the solitary Daurian ground squirrel and the social Mongolian gerbil. We show that plague prevalence in the Daurian ground squirrel is not detectably related to its trophic web, and that therefore surveillance efforts should focus on detecting plague directly in this ecosystem. On the other hand, plague in the Mongolian gerbil is strongly embedded in a complex, yet understandable trophic web of climate, vegetation, and rodent and flea densities, making the ecosystem suitable for more sophisticated low-cost surveillance practices, such as remote sensing. As for the trophic webs of the two rodent species, we find that increased vegetation is positively associated with higher temperatures and precipitation for both ecosystems. We furthermore find a positive association between vegetation and ground squirrel density, yet a negative association between vegetation and gerbil density. Our study thus shows how past surveillance records can be used to design and improve existing plague prevention and control measures, by tailoring them to individual plague foci. Such measures are indeed highly needed under present conditions with prevailing climate change. PMID:25540277

Fishes, mussels, crayfishes, and aquatic habitats of the Hoosier-Shawnee ecological assessment area

Science.gov (United States)

M. Burr Brooks; Justin T. Sipiorski; Matthew R. Thomas; Kevin S. Cummings; Christopher A. Taylor

2004-01-01

The Hoosier-Shawnee Ecological Assessment Area, part of the Coastal Plain and Interior Low Plateau physiographic provinces, includes 194 native fish species, 76 native mussel species, and 34 native crayfish species. Five of the subregions (e.g., Mississippi Embayment) that make up the assessment area were recently ranked as either globally or bioregionally outstanding...

Was Plague an Exclusively Urban Phenomenon? Plague Mortality in the Seventeenth-Century Low Countries

NARCIS (Netherlands)

Curtis, D.R.

2016-01-01

Current scholarship reinforces the notion that by the early modern period, plague had become largely an urban concern in northwestern Europe. However, a data set comprised of burial information from the seventeenth-century Low Countries suggests that plague’s impact on the countryside was far more

Climatic and evolutionary drivers of phase shifts in the plague epidemics of colonial India.

Science.gov (United States)

Lewnard, Joseph A; Townsend, Jeffrey P

2016-12-20

Immune heterogeneity in wild host populations indicates that disease-mediated selection is common in nature. However, the underlying dynamic feedbacks involving the ecology of disease transmission, evolutionary processes, and their interaction with environmental drivers have proven challenging to characterize. Plague presents an optimal system for interrogating such couplings: Yersinia pestis transmission exerts intense selective pressure driving the local persistence of disease resistance among its wildlife hosts in endemic areas. Investigations undertaken in colonial India after the introduction of plague in 1896 suggest that, only a decade after plague arrived, a heritable, plague-resistant phenotype had become prevalent among commensal rats of cities undergoing severe plague epidemics. To understand the possible evolutionary basis of these observations, we developed a mathematical model coupling environmentally forced plague dynamics with evolutionary selection of rats, capitalizing on extensive archival data from Indian Plague Commission investigations. Incorporating increased plague resistance among rats as a consequence of intense natural selection permits the model to reproduce observed changes in seasonal epidemic patterns in several cities and capture experimentally observed associations between climate and flea population dynamics in India. Our model results substantiate Victorian era claims of host evolution based on experimental observations of plague resistance and reveal the buffering effect of such evolution against environmental drivers of transmission. Our analysis shows that historical datasets can yield powerful insights into the transmission dynamics of reemerging disease agents with which we have limited contemporary experience to guide quantitative modeling and inference.

Eighteenth century Yersinia pestis genomes reveal the long-term persistence of an historical plague focus

OpenAIRE

Bos, Kirsten I; Herbig, Alexander; Sahl, Jason; Waglechner, Nicholas; Fourment, Mathieu; Forrest, Stephen A; Klunk, Jennifer; Schuenemann, Verena J; Poinar, Debi; Kuch, Melanie; Golding, G Brian; Dutour, Olivier; Keim, Paul; Wagner, David M; Holmes, Edward C

2016-01-01

eLife digest A bacterium called Yersina pestis is responsible for numerous human outbreaks of plague throughout history. It is carried by rats and other rodents and can spread to humans causing what we conventionally refer to as plague. The most notorious of these plague outbreaks ? the Black Death ? claimed millions of lives in Europe in the mid-14th century. Several other plague outbreaks emerged in Europe over the next 400 years. Then, there was a large gap before the plague re-emerged as ...

Crayfish Self-Administer Amphetamine in a Spatially Contingent Task

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Udita Datta

2018-05-01

Full Text Available Natural reward is an essential element of any organism’s ability to adapt to environmental variation. Its underlying circuits and mechanisms guide the learning process as they help associate an event, or cue, with the perception of an outcome’s value. More generally, natural reward serves as the fundamental generator of all motivated behavior. Addictive plant alkaloids are able to activate this circuitry in taxa ranging from planaria to humans. With modularly organized nervous systems and confirmed vulnerabilities to human drugs of abuse, crayfish have recently emerged as a compelling model for the study of the addiction cycle, including psychostimulant effects, sensitization, withdrawal, reinstatement, and drug reward in conditioned place preference paradigms. Here we extend this work with the demonstration of a spatially contingent, operant drug self-administration paradigm for amphetamine. When the animal enters a quadrant of the arena with a particular textured substrate, a computer-based control system delivers amphetamine through an indwelling fine-bore cannula. Resulting reward strength, dose-response, and the time course of operant conditioning were assessed. Individuals experiencing the drug contingent on their behavior, displayed enhanced rates of operant responses compared to that of their yoked (non-contingent counterparts. Application of amphetamine near the supra-esophageal ganglion elicited stronger and more robust increases in operant responding than did systemic infusions. This work demonstrates automated implementation of a spatially contingent self-administration paradigm in crayfish, which provides a powerful tool to explore comparative perspectives in drug-sensitive reward, the mechanisms of learning underlying the addictive cycle, and phylogenetically conserved vulnerabilities to psychostimulant compounds.

Highly pathogenic avian influenza.

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Swayne, D E; Suarez, D L

2000-08-01

Highly pathogenic (HP) avian influenza (AI) (HPAI) is an extremely contagious, multi-organ systemic disease of poultry leading to high mortality, and caused by some H5 and H7 subtypes of type A influenza virus, family Orthomyxoviridae. However, most AI virus strains are mildly pathogenic (MP) and produce either subclinical infections or respiratory and/or reproductive diseases in a variety of domestic and wild bird species. Highly pathogenic avian influenza is a List A disease of the Office International des Epizooties, while MPAI is neither a List A nor List B disease. Eighteen outbreaks of HPAI have been documented since the identification of AI virus as the cause of fowl plague in 1955. Mildly pathogenic avian influenza viruses are maintained in wild aquatic bird reservoirs, occasionally crossing over to domestic poultry and causing outbreaks of mild disease. Highly pathogenic avian influenza viruses do not have a recognised wild bird reservoir, but can occasionally be isolated from wild birds during outbreaks in domestic poultry. Highly pathogenic avian influenza viruses have been documented to arise from MPAI viruses through mutations in the haemagglutinin surface protein. Prevention of exposure to the virus and eradication are the accepted methods for dealing with HPAI. Control programmes, which imply allowing a low incidence of infection, are not an acceptable method for managing HPAI, but have been used during some outbreaks of MPAI. The components of a strategy to deal with MPAI or HPAI include surveillance and diagnosis, biosecurity, education, quarantine and depopulation. Vaccination has been used in some control and eradication programmes for AI.

Pattern and spatial distribution of plague in Lushoto, north-eastern ...

African Journals Online (AJOL)

A review of plague records from 1986 to 2002 and household interviews were carried out in the plague endemic villages to establish a pattern and spatial distribution of the disease in Lushoto district, Tanzania. Spatial data of households and village centres were collected and mapped using a hand held Global Positioning ...

Towards a theoretically informed policy against a rakghoul plague outbreak.

Science.gov (United States)

Kontopoulos, Dimitrios-Georgios; Kontopoulou, Theano; Ho, Hsi-Cheng; García-Carreras, Bernardo

2017-12-11

A long time ago in a galaxy far, far away, the Sith Lord Karness Muur engineered the rakghoul plague, a disease that transformed infected humans into near-mindless predatory rakghouls. At its peak, the disease infected millions of individuals, giving rise to armies of rakghouls on a number of planets. Whether rakghoul populations have persisted until this day is not known, making a rakghoul invasion on Earth not completely improbable. Further, a strategy for defence against an outbreak of the disease on Earth has not yet been proposed. To fill this glaring gap, we developed the first mathematical model of the population dynamics of humans and rakghouls during a rakghoul plague outbreak. Using New South Wales as a model site, we then obtained ensembles of model predictions for the outcome of the rakghoul plague in two different disease control strategy scenarios (population evacuation and military intervention), and in the absence thereof. Finally, based on these predictions, we propose a set of policy guidelines for successfully controlling and eliminating outbreaks of the rakghoul plague in Australian states.

The Formula of Plague Narratives

DEFF Research Database (Denmark)

Christensen, Jørgen Riber

2015-01-01

The article is a narratological investigation of a selection of plague tales. The selection spans millennia and different text types, technologies and genres, from The Bible to apocalyptical films, iPhone games and testimonials from Médecins Sans Frontières. The research question is whether...

Genetic characterization of Western European noble crayfish populations (Astacus astacus) for advanced conservation management strategies

NARCIS (Netherlands)

Schrimpf, A.; Piscione, M.; Cammaerts, R.; Collas, M.; Herman, D.; Jung, A.; Ottburg, F.; Roessink, I.; Rollin, X.; Schulz, R.; Theissinger, K.

2017-01-01

One central goal of conservation biology is to conserve the genetic diversity of species in order to protect their adaptive potential. The main objective of this study was to identify management units (MUs) for the threatened noble crayfish (Astacus astacus) in Western Europe by utilizing

Increased microsporidian parasitism of the crayfish Orconectes virilis in an experimentally acidified lake. [Thelohania contejeani

Energy Technology Data Exchange (ETDEWEB)

France, R.L.; Graham, L.

1985-10-01

Orconectes virilis has been identified as a host of the microsporidian Thelohania contejeani in four lakes in the Experimental Lakes Area (ELA), northwestern Ontario. Prevalence of parasitism increased from 1.7% in autumn 1979, to 6.5% and 7.7% in autumns 1980 and 1981 concomitant with experimental acidification of Lake 223 to pH 5.1. By comparison, mean infection rates observed within three reference lakes were between 0.3 to 0.6%. Enhanced microsporidosis is believed to have contributed to a reduction in annual crayfish survival rates for the Lake 223 population of 8% in 1979 and 18% in 1980 compared to averages calculated for the non-acidified lakes. Hypotheses to explain the ten-fold increase in Thelohania parasitism in Lake 223 over background levels for the ELA region include a) increased probagative ability due to elevated rate of crayfish cannibalism or low pH-favored parasite life cycle, and b) decreased host resistance when under sublethal stress.

Sylvatic plague vaccine partially protects prairie dogs (Cynomys spp.) in field trials

Science.gov (United States)

Rocke, Tonie E.; Tripp, Daniel W.; Russell, Robin E.; Abbott, Rachel C.; Richgels, Katherine; Matchett, Marc R.; Biggins, Dean E.; Griebel, Randall; Schroeder, Greg; Grassel, Shaun M.; Pipkin, David R.; Cordova, Jennifer; Kavalunas, Adam; Maxfield, Brian; Boulerice, Jesse; Miller, Michael W.

2017-01-01

Sylvatic plague, caused by Yersinia pestis, frequently afflicts prairie dogs (Cynomys spp.), causing population declines and local extirpations. We tested the effectiveness of bait-delivered sylvatic plague vaccine (SPV) in prairie dog colonies on 29 paired placebo and treatment plots (1–59 ha in size; average 16.9 ha) in 7 western states from 2013 to 2015. We compared relative abundance (using catch per unit effort (CPUE) as an index) and apparent survival of prairie dogs on 26 of the 29 paired plots, 12 with confirmed or suspected plague (Y. pestis positive carcasses or fleas). Even though plague mortality occurred in prairie dogs on vaccine plots, SPV treatment had an overall positive effect on CPUE in all three years, regardless of plague status. Odds of capturing a unique animal were 1.10 (95% confidence interval [C.I.] 1.02–1.19) times higher per trap day on vaccine-treated plots than placebo plots in 2013, 1.47 (95% C.I. 1.41–1.52) times higher in 2014 and 1.19 (95% C.I. 1.13–1.25) times higher in 2015. On pairs where plague occurred, odds of apparent survival were 1.76 (95% Bayesian credible interval [B.C.I.] 1.28–2.43) times higher on vaccine plots than placebo plots for adults and 2.41 (95% B.C.I. 1.72–3.38) times higher for juveniles. Our results provide evidence that consumption of vaccine-laden baits can protect prairie dogs against plague; however, further evaluation and refinement are needed to optimize SPV use as a management tool.

Influence of human activity patterns on epidemiology of plague in Western Usambara Mountains, Tanzania.

Science.gov (United States)

Hubeau, Marianne; Gulinck, Hubert; Kimaro, Didas N; Hieronimo, Proches; Meliyo, Joel

2014-07-01

Human plague has been a recurring public health threat in some villages in the Western Usambara Mountains, Tanzania, in the period between 1980 and 2004. Despite intensive past biological and medical research, the reasons for the plague outbreaks in the same set of villages remain unknown. Plague research needs to broaden its scope and formulate new hypotheses. This study was carried out to establish relationships between the nature and the spatial extent of selected human activities on one hand, and the reported plague cases on the other hand. Three outdoor activities namely, fetching water, collecting firewood and going to the market, were selected. Through enquiries the activity patterns related to these activities were mapped in 14 villages. Standard deviation ellipses represent the extent of action spaces. Over 130 activity types were identified and listed. Of these, fetching water, collecting firewood and going to the market were used for further analysis. The results indicate a significant correlation between the plague frequency and the size of these action spaces. Different characteristics of land use and related human activities were correlated with the plague frequency at village and hamlet levels. Significant relationships were found between plague frequency and specific sources of firewood and water, and specific market places.

Role of the Yersinia pestis yersiniabactin iron acquisition system in the incidence of flea-borne plague.

Directory of Open Access Journals (Sweden)

Florent Sebbane

2010-12-01

Full Text Available Plague is a flea-borne zoonosis caused by the bacterium Yersinia pestis. Y. pestis mutants lacking the yersiniabactin (Ybt siderophore-based iron transport system are avirulent when inoculated intradermally but fully virulent when inoculated intravenously in mice. Presumably, Ybt is required to provide sufficient iron at the peripheral injection site, suggesting that Ybt would be an essential virulence factor for flea-borne plague. Here, using a flea-to-mouse transmission model, we show that a Y. pestis strain lacking the Ybt system causes fatal plague at low incidence when transmitted by fleas. Bacteriology and histology analyses revealed that a Ybt-negative strain caused only primary septicemic plague and atypical bubonic plague instead of the typical bubonic form of disease. The results provide new evidence that primary septicemic plague is a distinct clinical entity and suggest that unusual forms of plague may be caused by atypical Y. pestis strains.

Genetic variation at the MHC DRB1 locus is similar across Gunnison's prairie dog (Cynomys gunnisoni) colonies regardless of plague history

Science.gov (United States)

Cobble, Kacy R.; Califf, Katy J.; Stone, Nathan E.; Shuey, Megan M.; Birdsell, Dawn; Colman, Rebecca E.; Schupp, James M.; Aziz, Maliha; Van Andel, Roger; Rocke, Tonie E.; Wagner, David M.; Busch, Joseph D.

2016-01-01

Yersinia pestis was introduced to North America around 1900 and leads to nearly 100% mortality in prairie dog (Cynomys spp.) colonies during epizootic events, which suggests this pathogen may exert a strong selective force. We characterized genetic diversity at an MHC class II locus (DRB1) in Gunnison's prairie dog (C. gunnisoni) and quantified population genetic structure at the DRB1versus 12 microsatellite loci in three large Arizona colonies. Two colonies, Seligman (SE) and Espee Ranch (ES), have experienced multiple plague-related die-offs in recent years, whereas plague has never been documented at Aubrey Valley (AV). We found fairly low allelic diversity at the DRB1 locus, with one allele (DRB1*01) at high frequency (0.67–0.87) in all colonies. Two otherDRB1 alleles appear to be trans-species polymorphisms shared with the black-tailed prairie dog (C. ludovicianus), indicating that these alleles have been maintained across evolutionary time frames. Estimates of genetic differentiation were generally lower at the MHC locus (FST = 0.033) than at microsatellite markers (FST = 0.098). The reduced differentiation at DRB1 may indicate that selection has been important for shaping variation at MHC loci, regardless of the presence or absence of plague in recent decades. However, genetic drift has probably also influenced theDRB1 locus because its level of differentiation was not different from that of microsatellites in anFST outlier analysis. We then compared specific MHC alleles to plague survivorship in 60C. gunnisoni that had been experimentally infected with Y. pestis. We found that survival was greater in individuals that carried at least one copy of the most common allele (DRB1*01) compared to those that did not (60% vs. 20%). Although the sample sizes of these two groups were unbalanced, this result suggests the possibility that this MHC class II locus, or a nearby linked gene, could play a role in plague survival.

Enzootic plague reduces black-footed ferret (Mustela nigripes) survival in Montana

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Matchett, Marc R.; Biggins, Dean E.; Carlson, Valerie; Powell, Bradford; Rocke, Tonie E.

2010-01-01

Black-footed ferrets (Mustela nigripes) require extensive prairie dog colonies (Cynomys spp.) to provide habitat and prey. Epizootic plague kills both prairie dogs and ferrets and is a major factor limiting recovery of the highly endangered ferret. In addition to epizootics, we hypothesized that enzootic plague, that is, presence of disease-causing Yersinia pestis without any noticeable prairie dog die off, may also affect ferret survival. We reduced risk of plague on portions of two ferret reintroduction areas by conducting flea control for 3 years. Beginning in 2004, about half of the ferrets residing on dusted and nondusted colonies were vaccinated against plague with an experimental vaccine (F1-V fusion protein). We evaluated 6-month reencounter rates (percentage of animals observed at the end of an interval that were known alive at the beginning of the interval), an index to survival, for ferrets in four treatment groups involving all combinations of vaccination and flea control. For captive-reared ferrets (115 individuals observed across 156 time intervals), reencounter rates were higher for vaccinates (0.44) than for nonvaccinates (0.23, p = 0.044) on colonies without flea control, but vaccination had no detectable effect on colonies with flea control (vaccinates = 0.41, nonvaccinates = 0.42, p = 0.754). Flea control resulted in higher reencounter rates for nonvaccinates (p = 0.026), but not for vaccinates (p = 0.508). The enhancement of survival due to vaccination or flea control supports the hypothesis that enzootic plague reduces ferret survival, even when there was no noticeable decline in prairie dog abundance. The collective effects of vaccination and flea control compel a conclusion that fleas are required for maintenance, and probably transmission, of plague at enzootic levels. Other studies have demonstrated similar effects of flea control on several species of prairie dogs and, when combined with this study, suggest

Climate-driven introduction of the Black Death and successive plague reintroductions into Europe.

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Schmid, Boris V; Büntgen, Ulf; Easterday, W Ryan; Ginzler, Christian; Walløe, Lars; Bramanti, Barbara; Stenseth, Nils Chr

2015-03-10

The Black Death, originating in Asia, arrived in the Mediterranean harbors of Europe in 1347 CE, via the land and sea trade routes of the ancient Silk Road system. This epidemic marked the start of the second plague pandemic, which lasted in Europe until the early 19th century. This pandemic is generally understood as the consequence of a singular introduction of Yersinia pestis, after which the disease established itself in European rodents over four centuries. To locate these putative plague reservoirs, we studied the climate fluctuations that preceded regional plague epidemics, based on a dataset of 7,711 georeferenced historical plague outbreaks and 15 annually resolved tree-ring records from Europe and Asia. We provide evidence for repeated climate-driven reintroductions of the bacterium into European harbors from reservoirs in Asia, with a delay of 15 ± 1 y. Our analysis finds no support for the existence of permanent plague reservoirs in medieval Europe.

Climate-driven introduction of the Black Death and successive plague reintroductions into Europe

Science.gov (United States)

Büntgen, Ulf; Easterday, W. Ryan; Ginzler, Christian; Walløe, Lars; Bramanti, Barbara; Stenseth, Nils Chr.

2015-01-01

The Black Death, originating in Asia, arrived in the Mediterranean harbors of Europe in 1347 CE, via the land and sea trade routes of the ancient Silk Road system. This epidemic marked the start of the second plague pandemic, which lasted in Europe until the early 19th century. This pandemic is generally understood as the consequence of a singular introduction of Yersinia pestis, after which the disease established itself in European rodents over four centuries. To locate these putative plague reservoirs, we studied the climate fluctuations that preceded regional plague epidemics, based on a dataset of 7,711 georeferenced historical plague outbreaks and 15 annually resolved tree-ring records from Europe and Asia. We provide evidence for repeated climate-driven reintroductions of the bacterium into European harbors from reservoirs in Asia, with a delay of 15 ± 1 y. Our analysis finds no support for the existence of permanent plague reservoirs in medieval Europe. PMID:25713390

The influence of coarse-scale environmental features on current and predicted future distributions of narrow-range endemic crayfish populations

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Dyer, Joseph J.; Brewer, Shannon K.; Worthington, Thomas A.; Bergey, Elizabeth A.

2013-01-01

1.A major limitation to effective management of narrow-range crayfish populations is the paucity of information on the spatial distribution of crayfish species and a general understanding of the interacting environmental variables that drive current and future potential distributional patterns. 2.Maximum Entropy Species Distribution Modeling Software (MaxEnt) was used to predict the current and future potential distributions of four endemic crayfish species in the Ouachita Mountains. Current distributions were modelled using climate, geology, soils, land use, landform and flow variables thought to be important to lotic crayfish. Potential changes in the distribution were forecast by using models trained on current conditions and projecting onto the landscape predicted under climate-change scenarios. 3.The modelled distribution of the four species closely resembled the perceived distribution of each species but also predicted populations in streams and catchments where they had not previously been collected. Soils, elevation and winter precipitation and temperature most strongly related to current distributions and represented 6587% of the predictive power of the models. Model accuracy was high for all models, and model predictions of new populations were verified through additional field sampling. 4.Current models created using two spatial resolutions (1 and 4.5km2) showed that fine-resolution data more accurately represented current distributions. For three of the four species, the 1-km2 resolution models resulted in more conservative predictions. However, the modelled distributional extent of Orconectes leptogonopodus was similar regardless of data resolution. Field validations indicated 1-km2 resolution models were more accurate than 4.5-km2 resolution models. 5.Future projected (4.5-km2 resolution models) model distributions indicated three of the four endemic species would have truncated ranges with low occurrence probabilities under the low-emission scenario

[The spread of the plague: A sciento-historiographic review].

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Cuadrada, Coral

2015-01-01

There is still uncertainty about the diagnosis and nature of the plague; some scholars have been forced to abandon certainties and be filled with doubts: from believing that the mediaeval Black Plague was, in reality, the bubonic plague (although with unusual characteristics) to stating that there is very little evidence to support a retro-diagnosis. This article looks at this in depth, not only reviewing the historiography but also giving new interpretations which question previous hypotheses through research on images of the time, comparing them to the most recent investigative data. Two primary sources are analysed: Renaissance treaties written by four Italian doctors: Michele Savonarola, Marsilio Ficino, Leonardo Fioravanti and Gioseffo Daciano; and iconography: an illustrated manuscript of the Decameron by Giovanni Boccaccio and a Hebrew Haggadah from the XIVth century. The results are compared to the most recent research on DNA and in micropaleontology.

Age at Vaccination May Influence Response to Sylvatic Plague Vaccine (SPV) in Gunnison's Prairie Dogs (Cynomys gunnisoni).

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Rocke, Tonie E; Tripp, Dan; Lorenzsonn, Faye; Falendysz, Elizabeth; Smith, Susan; Williamson, Judy; Abbott, Rachel

2015-06-01

Gunnison's prairie dogs (Cynomys gunnisoni) have been considered at greater risk from Yersinia pestis (plague) infection in the montane portion of their range compared to populations at lower elevations, possibly due to factors related to flea transmission of the bacteria or greater host susceptibility. To test the latter hypothesis and determine whether vaccination against plague with an oral sylvatic plague vaccine (SPV) improved survival, we captured prairie dogs from a C. g. gunnisoni or "montane" population and a C. g. zuniensis or "prairie" population for vaccine efficacy and challenge studies. No differences (P = 0.63) were found in plague susceptibility in non-vaccinated animals between these two populations; however, vaccinates from the prairie population survived plague challenge at significantly higher rates (P plague challenge at a much higher rate than adults (P plague in the C. g. gunnisoni or "montane" populations of Gunnison's prairie dogs, and that SPV could be a useful plague management tool for this species, particularly if targeted at younger cohorts.

Plague in Egypt: Disease biology, history and contemporary analysis: A minireview

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Wael M. Lotfy

2015-07-01

Full Text Available Plague is a zoonotic disease with a high mortality rate in humans. Unfortunately, it is still endemic in some parts of the world. Also, natural foci of the disease are still found in some countries. Thus, there may be a risk of global plague re-emergence. This work reviews plague biology, history of major outbreaks, and threats of disease re-emergence in Egypt. Based on the suspected presence of potential natural foci in the country, the global climate change, and the threat posed by some neighbouring countries disease re-emergence in Egypt should not be excluded. The country is in need for implementation of some preventive measures.

Ecologic Features of Plague Outbreak Areas, Democratic Republic of the Congo, 2004–2014

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Shako, Jean-Christophe; Gaudart, Jean; Sudre, Bertrand; Ilunga, Benoit Kebela; Shamamba, Stomy Karhemere Bi; Diatta, Georges; Davoust, Bernard; Tamfum, Jean-Jacques Muyembe; Piarroux, Renaud; Piarroux, Martine

2018-01-01

During 2004–2014, the Democratic Republic of the Congo (DRC) declared 54% of plague cases worldwide. Using national data, we characterized the epidemiology of human plague in DRC for this period. All 4,630 suspected human plague cases and 349 deaths recorded in DRC came from Orientale Province. Pneumonic plague cases (8.8% of total) occurred during 2 major outbreaks in mining camps in the equatorial forest, and some limited outbreaks occurred in the Ituri highlands. Epidemics originated in 5 health zones clustered in Ituri, where sporadic bubonic cases were recorded throughout every year. Classification and regression tree characterized this cluster by the dominance of ecosystem 40 (mountain tropical climate). In conclusion, a small, stable, endemic focus of plague in the highlands of the Ituri tropical region persisted, acting as a source of outbreaks in DRC. PMID:29350136

[The Antonine Plague and the decline of the Roman Empire].

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Sabbatani, S; Fiorino, S

2009-12-01

The Antonine Plague, which flared up during the reign of Marcus Aurelius from 165 AD and continued under the rule of his son Commodus, played such a major role that the pathocenosis in the Ancient World was changed. The spread of the epidemic was favoured by the occurrence of two military episodes in which Marcus Aurelius himself took part: the Parthian War in Mesopotamia and the wars against the Marcomanni in northeastern Italy, in Noricum and in Pannonia. Accounts of the clinical features of the epidemic are scant and disjointed, with the main source being Galen, who witnessed the plague. Unfortunately, the great physician provides us with only a brief presentation of the disease, his aim being to supply therapeutic approaches, thus passing over the accurate description of the disease symptoms. Although the reports of some clinical cases treated by Galen lead us to think that the Antonine plague was caused by smallpox, palaeopathological confirmation is lacking. Some archaeological evidence (such as terracotta finds) from Italy might reinforce this opinion. In these finds, some details can be observed, suggesting the artist's purpose to represent the classic smallpox pustules, typical signs of the disease. The extent of the epidemic has been extensively debated: the majority of authors agree that the impact of the plague was severe, influencing military conscription, the agricultural and urban economy, and depleting the coffers of the State. The Antonine plague affected ancient Roman traditions, also leaving a mark on artistic expression; a renewal of spirituality and religiousness was recorded. These events created the conditions for the spread of monotheistic religions, such as Mithraism and Christianity. This period, characterized by health, social and economic crises, paved the way for the entry into the Empire of neighbouring barbarian tribes and the recruitment of barbarian troops into the Roman army; these events particularly favoured the cultural and

Where does human plague still persist in Latin America?

OpenAIRE

Maria Cristina Schneider; Patricia Najera; Sylvain Aldighieri; Deise I Galan; Eric Bertherat; Alfonso Ruiz; Elsy Dumit; Jean Marc Gabastou; Marcos A Espinal

2014-01-01

Background Plague is an epidemic-prone disease with a potential impact on public health, international trade, and tourism. It may emerge and re-emerge after decades of epidemiological silence. Today, in Latin America, human cases and foci are present in Bolivia, Brazil, Ecuador, and Peru. Aims The objective of this study is to identify where cases of human plague still persist in Latin America and map areas that may be at risk for emergence or re-emergence. This analysis will provide evidence...

Predicting Potential Risk Areas of Human Plague for the Western Usambara Mountains, Lushoto District, Tanzania

DEFF Research Database (Denmark)

Neerinckx, Simon; Peterson, A Townsend; Gulinck, Hubert

2010-01-01

A natural focus of plague exists in the Western Usambara Mountains of Tanzania. Despite intense research, questions remain as to why and how plague emerges repeatedly in the same suite of villages. We used human plague incidence data for 1986-2003 in an ecological-niche modeling framework to expl...

Spatiotemporal modelling and mapping of the bubonic plague epidemic in India

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Christakos George

2006-03-01

Full Text Available Abstract Background This work studies the spatiotemporal evolution of bubonic plague in India during 1896–1906 using stochastic concepts and geographical information science techniques. In the past, most investigations focused on selected cities to conduct different kinds of studies, such as the ecology of rats. No detailed maps existed incorporating the space-time dependence structure and uncertainty sources of the epidemic system and providing a composite space-time picture of the disease propagation characteristics. Results Informative spatiotemporal maps were generated that represented mortality rates and geographical spread of the disease, and epidemic indicator plots were derived that offered meaningful characterizations of the spatiotemporal disease distribution. The bubonic plague in India exhibited strong seasonal and geographical features. During its entire duration, the plague continued to invade new geographical areas, while it followed a re-emergence pattern at many localities; its rate changed significantly during each year and the mortality distribution exhibited space-time heterogeneous patterns; prevalence usually occurred in the autumn and spring, whereas the plague stopped moving towards new locations during the summers. Conclusion Modern stochastic modelling and geographical information science provide powerful means to study the spatiotemporal distribution of the bubonic plague epidemic under conditions of uncertainty and multi-sourced databases; to account for various forms of interdisciplinary knowledge; and to generate informative space-time maps of mortality rates and propagation patterns. To the best of our knowledge, this kind of plague maps and plots become available for the first time, thus providing novel perspectives concerning the distribution and space-time propagation of the deadly epidemic. Furthermore, systematic maps and indicator plots make possible the comparison of the spatial-temporal propagation

Human activity spaces and plague risks in three contrasting landscapes in Lushoto District, Tanzania.

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Hieronimo, Proches; Gulinck, Hubert; Kimaro, Didas N; Mulungu, Loth S; Kihupi, Nganga I; Msanya, Balthazar M; Leirs, Herwig; Deckers, Jozef A

2014-07-01

Since 1980 plague has been a human threat in the Western Usambara Mountains in Tanzania. However, the spatial-temporal pattern of plague occurrence remains poorly understood. The main objective of this study was to gain understanding of human activity patterns in relation to spatial distribution of fleas in Lushoto District. Data were collected in three landscapes differing in plague incidence. Field survey coupled with Geographic Information System (GIS) and physical sample collections were used to collect data in wet (April to June 2012) and dry (August to October 2012) seasons. Data analysis was done using GIS, one-way ANOVA and nonparametric statistical tools. The degree of spatial co-occurrence of potential disease vectors (fleas) and humans in Lushoto focus differs significantly (p ≤ 0.05) among the selected landscapes, and in both seasons. This trend gives a coarse indication of the possible association of the plague outbreaks and the human frequencies of contacting environments with fleas. The study suggests that plague surveillance and control programmes at landscape scale should consider the existence of plague vector contagion risk gradient from high to low incidence landscapes due to human presence and intensity of activities.

Earthquakes and plague during Byzantine times: can lessons from the past improve epidemic preparedness.

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Tsiamis, Costas; Poulakou-Rebelakou, Effie; Marketos, Spyros

2013-01-01

Natural disasters have always been followed by a fear of infectious diseases. This raised historical debate about one of the most feared scenarios: the outbreak of bubonic plague caused by Yersinia pestis. One such event was recorded in the Indian state Maharashtra in 1994 after an earthquake. In multidisciplinary historical approach to the evolution of plague, many experts ignore the possibility of natural foci and their activation. This article presents historical records from the Byzantine Empire about outbreaks of the Plague of Justinian occurring months or even up to a year after high-magnitude earthquakes. Historical records of plague outbreaks can be used to document existence of natural foci all over the world. Knowledge of these historical records and the contemporary examples of plague support the assumption that, in terms of organising humanitarian aid, poor monitoring of natural foci could lead to unpredictable epidemiological consequences after high-magnitude earthquakes.

[Analysis on the results of etiology and serology of plague in Qinghai province from 2001 to 2010].

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Yang, Yonghai; Wang, Mei; Zhao, Xiaolong; Zhao, Zhongzhi; Zhang, Aiping; Wei, Rongjie; Wei, Baiqing; Wang, Zuyun

2014-02-01

To analyze the results of etiology and serology of plague among human and infected animals in Qinghai province from 2001 to 2010. Thirty-seven cases of human infected with plague, 53 541 different animal samples, 5 685 sets of vector insects flea and 49 039 different animal serum samples were obtained between 2001 and 2010. A total of 7 811 samples of serum from healthy farmers and herdsmen in 14 counties in Qinghai from 2005 to 2007 were collected. Yersinia pestis (Y. pestis) were detected in visceral and secretions from human, infected animals and vector insects, respectively. Plague antigen was detected by reverse indirect hemagglutination assay (RIHA) in those samples. Indirect hemagglutination assay (IHA) was used to test plague FI antibody in serum of human and infected animals. 37 human plague cases were confirmed, 21 strains of plague Y. pestis were isolated from human cases and 14 positive were detected out. 133 of 7 811 samples of human serum were IHA positive, with the positive rate at 1.7%. A total of 146 strains of plague were isolated from infected animals and vector insects, 99 out of which were from infected animals, with a ratio of Marmota himalayan at 72.7% (72/99) and the other 47 were from vector insects, with a ratio of callopsylla solaris at 68.1% (32/47). The number of IHA and PIHA positive were 300 and 10, respectively. A total of 3 animals and 3 insects species were identified as new epidemic hosts for plague. The natural plague focus of Microtus fuscus was discovered and confirmed and coexisted with natural focus of Marmota himalayan in Chengduo county, Yushu prefecture. The epidemic situation of plague is distributed mainly in Haixi, Yushu and Hainan prefectures. From 2001 to 2010, animal infected with plague was detected in successive years and human plague was very common in Qinghai. New infected animals and vector insects species and new epidemic areas were confirmed, hence the trend of plague prevalence for humans and animals is very

Identification of risk factors for plague in the West Nile Region of Uganda.

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Eisen, Rebecca J; MacMillan, Katherine; Atiku, Linda A; Mpanga, Joseph T; Zielinski-Gutierrez, Emily; Graham, Christine B; Boegler, Karen A; Enscore, Russell E; Gage, Kenneth L

2014-06-01

Plague is an often fatal, primarily flea-borne rodent-associated zoonosis caused by Yersinia pestis. We sought to identify risk factors for plague by comparing villages with and without a history of human plague cases within a model-defined plague focus in the West Nile Region of Uganda. Although rat (Rattus rattus) abundance was similar inside huts within case and control villages, contact rates between rats and humans (as measured by reported rat bites) and host-seeking flea loads were higher in case villages. In addition, compared with persons in control villages, persons in case villages more often reported sleeping on reed or straw mats, storing food in huts where persons sleep, owning dogs and allowing them into huts where persons sleep, storing garbage inside or near huts, and cooking in huts where persons sleep. Compared with persons in case villages, persons in control villages more commonly reported replacing thatch roofing, and growing coffee, tomatoes, onions, and melons in agricultural plots adjacent to their homesteads. Rodent and flea control practices, knowledge of plague, distance to clinics, and most care-seeking practices were similar between persons in case villages and persons in control villages. Our findings reinforce existing plague prevention recommendations and point to potentially advantageous local interventions. © The American Society of Tropical Medicine and Hygiene.

The Second Plague Pandemic in the Golden Horde and Its Consequences

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T.F. Khaydarov

2014-12-01

Full Text Available The article reviews the reasons for origin and consequences of spreading for the second plague pandemic in the Golden Horde. By applying scientific data from biology, climatology, medicine, and history, authors come to a conclusion that a large number of natural plague pestholes existed initially in the Ulus of Jochi. Numerous historical sources mentioned plague outbreaks but all of them were of purely local character. The bubonic type of plague characterized by a longer period of illness and an insignificant number of lethal episodes was spread more widely. In the mid-40s of the 14th century a new form of disease, the lung plague, came into existence. It was corpse blackening of the deceased from this type of plague that gave name to the whole pandemic – the “Black Death”. The speed of its progress and spreading significantly exceeded those of the bubonic type and 100% of mortality was recorded among the diseased. However, as historical data show, the outbreak of the lung plague continued in the territory of the Golden Horde from 1346 to 1349. In their article authors prove that one of the most important reasons for the emergence of the lung type was the change in migration flows of Eurasian rodents caused by depletion of nutritional resources in the steppe and serious climatic changes. All other outbreaks of the Black Death are viewed as continuation of the first wave of the disease and their emergence is explained through activity of two natural pestholes (the Relict North-Western and the Lower Volga ones. Consequences of the the first wave were much less substantial for the Ulus of Jochi than those of the following outbreaks (in 1364, 1374, and 1395. The main consequences of the next waves of the disease were: final establishment of 4 political centers (Grand Duchy of Moscow, the Bulgar and the Crimean uluses, and the Blue Horde striving for political leadership in the territory of the former Golden Horde; establishment of a new ethnic

Fumigating the Hygienic Model City: Bubonic Plague and the Sulfurozador in Early-Twentieth-Century Buenos Aires.

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Engelmann, Lukas

2018-07-01

The 1899/1900 arrival of bubonic plague in Argentina had thrown the model status of Buenos Aires as a hygienic city into crisis. Where the idea of foreign threats and imported epidemics had dominated the thinking of Argentina's sanitarians at that time, plague renewed concerns about hidden threats within the fabric of the capital's dense environment; concerns that led to new sanitary measures and unprecedented rat-campaigns supported by the large-scale application of sulphur dioxide. The article tells the story of early twentieth-century urban sanitation in Buenos Aires through the lens of a new industrial disinfection apparatus. The Aparato Marot, also known as Sulfurozador was acquired and integrated in the capital's sanitary administration by the epidemiologist José Penna in 1906 to materialise two key lessons learned from plague. First, the machine was supposed to translate the successful disinfection practices of global maritime sanitation into urban epidemic control in Argentina. Second, the machine's design enabled public health authorities to reinvigorate a traditional hygienic concern for the entirety of the city's terrain. While the Sulfurozador offered effective destruction of rats, it promised also a comprehensive - and utopian - disinfection of the whole city, freeing it from all imaginable pathogens, insects as well as rodents. In 1910, the successful introduction of the Sulfurozador encouraged Argentina's medico-political elite to introduce a new principle of 'general prophylaxis'. This article places the apparatus as a technological modernisation of traditional sanitary practices in the bacteriological age, which preserved the urban environment - 'el terreno' - as a principal site of intervention. Thus, the Sulfurozador allowed the 'higienistas' to sustain a long-standing utopian vision of all-encompassing social, bodily and political hygiene into the twentieth century.

Effects of cadmium on the biochemical composition of the freshwater crayfish Procambarus clarkii (Girard, 1852)

Energy Technology Data Exchange (ETDEWEB)

Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

1991-12-01

Lake Albufera of Valencia (Spain) and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic residues. Among these residues include heavy metals which have been deposited from the many urban and waste waters in this area. The American red crayfish, Procambarus clarkii from Albufera Lake has high resistance to heavy metals. The authors have also found that P. clarkii shows a high capacity for cadmium accumulation in experimental conditions and natural conditions since crayfish collected in this area contained considerable amounts of cadmium in several tissues even after 15 days of depuration in clean water. Since the physiological changes that take place when organisms are exposed to sublethal levels of stress could include rate of feeding as well as respiration and excretion, the net result could be a change in energy available for growth and reproduction. In this work, the authors have studied the biochemical energy composition of hepatopancreas, muscle and gills of P. clarkii after short term sublethal exposure to cadmium.

A plague on five of your houses - statistical re-assessment of three pneumonic plague outbreaks that occurred in Suffolk, England, between 1906 and 1918

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Egan Joseph R

2010-10-01

Full Text Available Abstract Background Plague is a re-emerging disease and its pneumonic form is a high priority bio-terrorist threat. Epidemiologists have previously analysed historical outbreaks of pneumonic plague to better understand the dynamics of infection, transmission and control. This study examines 3 relatively unknown outbreaks of pneumonic plague that occurred in Suffolk, England, during the first 2 decades of the twentieth century. Methods The Kolmogorov-Smirnov statistical test is used to compare the symptomatic period and the length of time between successive cases (i.e. the serial interval with previously reported values. Consideration is also given to the case fatality ratio, the average number of secondary cases resulting from each primary case in the observed minor outbreaks (termed Rminor, and the proportion of individuals living within an affected household that succumb to pneumonic plague via the index case (i.e. the household secondary attack rate (SAR. Results 2 of the 14 cases survived giving a case fatality ratio of 86% (95% confidence interval (CI = {57%, 98%}. For the 12 fatal cases, the average symptomatic period was 3.3 days (standard deviation (SD = 1.2 days and, for the 11 non index cases, the average serial interval was 5.8 days (SD = 2.0 days. Rminor was calculated to be 0.9 (SD = 1.0 and, in 2 households, the SAR was approximately 14% (95% CI = {0%, 58%} and 20% (95% CI = {1%, 72%}, respectively. Conclusions The symptomatic period was approximately 1 day longer on average than in an earlier study but the serial interval was in close agreement with 2 previously reported values. 2 of the 3 outbreaks ended without explicit public health interventions; however, non-professional caregivers were particularly vulnerable - an important public health consideration for any future outbreak of pneumonic plague.

[Risk assessments and control strategies of plague in five key surveillance counties, Zhejiang province].

Science.gov (United States)

Shi, Guoxiang; Ju, Cheng; Zhang, Rong; Zhang, Zheng; Sun, Jimin; Wang, Miaoruo; Zhang, Xiaohe; Ye, Xianming; Zhu, Zhihong; Xing, Jianguang; Liao, Xiaowei; Chen, Zhiping

2015-10-01

To analyze the epidemiology data on plague in five counties in Zhejiang province and to evaluate the risk of plague in theses areas. We selected five monitoring stations as a risk assessment (Qingyuan county, Longquan city, Yiwu city, Wencheng county, and Ruian city) in Zhejiang province where the plague epidemic more serious in the history. At least one constant site and 1-4 variable sites where plague occurred in history were selected for monitoring. We collected the five counties (cities) surveillance data of indoor rat density, indoor Rattus flavipectus density, the Xenopsylla cheopis index of rat, the Xenopsylla cheopis index of Rattus flavipectus in 1995-2014. Isolation of Yersinia pestis was conducted among 171,201 liver samples and F1 antibody were detected among 228,775 serum samples. Risk matrix, Borda count method, and Delphi approach were conducted to assess risk of the plague of five counties (cities) in Zhejiang province. Indoor rat density in Qingyuan county, Longquan city, Yiwu city, Wencheng county, Ruian city was 1.58%-5.50%, 1.13%-9.76%, 0.56%-3.67%, 2.83%-16.08%, 7.16%-15.96%, respectively; Indoor Rattus flavipectus density of five counties (cities) was 0.08%-2.23%, 0-2.02%, 0-0.54%, 0.71%-5.58%, 0.55%-4.92%, respectively. The Xenopsylla cheopis index of rat in Qingyuan county and Wencheng county was 0.011-0.500 and 0.015-0.227, respectively; The Xenopsylla cheopis index of Rattus flavipectus of Qingyuan county and Wencheng county was 0.119-3.412 and 0.100-1.430, respectively; Ruian City and Yiwu city cannot collected Xenopsylla cheopis, Long quan city only collected the Xenopsylla cheopis index of rat in the five years. Yersinia pestis were not isolated in five counties (cities).There were 3 Apodemus agrarius samples positive of plague F1 antibody test, in Longquan city and Yiwu city in 2005. Borda count method to assess the Longquan city, Yiwu (Borda point were both 321) plague risk was higher than three other regions; Delphi approach to

Paleoclimate and bubonic plague: a forewarning of future risk?

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McMichael Anthony J

2010-08-01

Full Text Available Abstract Pandemics of bubonic plague have occurred in Eurasia since the sixth century ad. Climatic variations in Central Asia affect the population size and activity of the plague bacterium's reservoir rodent species, influencing the probability of human infection. Using innovative time-series analysis of surrogate climate records spanning 1,500 years, a study in BMC Biology concludes that climatic fluctuations may have influenced these pandemics. This has potential implications for health risks from future climate change. See research article http://www.biomedcentral.com/1741-7007/8/112

Landscape and Residential Variables Associated with Plague-Endemic Villages in the West Nile Region of Uganda

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MacMillan, Katherine; Enscore, Russell E.; Ogen-Odoi, Asaph; Borchert, Jeff N.; Babi, Nackson; Amatre, Gerald; Atiku, Linda A.; Mead, Paul S.; Gage, Kenneth L.; Eisen, Rebecca J.

2011-01-01

Plague, caused by the bacteria Yersinia pestis, is a severe, often fatal disease. This study focuses on the plague-endemic West Nile region of Uganda, where limited information is available regarding environmental and behavioral risk factors associated with plague infection. We conducted observational surveys of 10 randomly selected huts within historically classified case and control villages (four each) two times during the dry season of 2006 (N = 78 case huts and N = 80 control huts), which immediately preceded a large plague outbreak. By coupling a previously published landscape-level statistical model of plague risk with this observational survey, we were able to identify potential residence-based risk factors for plague associated with huts within historic case or control villages (e.g., distance to neighboring homestead and presence of pigs near the home) and huts within areas previously predicted as elevated risk or low risk (e.g., corn and other annual crops grown near the home, water storage in the home, and processed commercial foods stored in the home). The identified variables are consistent with current ecologic theories on plague transmission dynamics. This preliminary study serves as a foundation for future case control studies in the area. PMID:21363983

Evidence of Yersinia pestis DNA from fleas in an endemic plague area of Zambia

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Hang'ombe Bernard M

2012-01-01

Full Text Available Abstract Background Yersinia pestis is a bacterium that causes plague which infects a variety of mammals throughout the world. The disease is usually transmitted among wild rodents through a flea vector. The sources and routes of transmission of plague are poorly researched in Africa, yet remains a concern in several sub-Saharan countries. In Zambia, the disease has been reported on annual basis with up to 20 cases per year, without investigating animal reservoirs or vectors that may be responsible in the maintenance and propagation of the bacterium. In this study, we undertook plague surveillance by using PCR amplification of the plasminogen activator gene in fleas. Findings Xenopsylla species of fleas were collected from 83 rodents trapped in a plague endemic area of Zambia. Of these rodents 5 had fleas positive (6.02% for Y. pestis plasminogen activator gene. All the Y. pestis positive rodents were gerbils. Conclusions We conclude that fleas may be responsible in the transmission of Y. pestis and that PCR may provide means of plague surveillance in the endemic areas of Zambia.

Further development of raccoon poxvirus-vectored vaccines against plague (Yersinia pestis)

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Rocke, Tonie E.; Iams, Keith P.; Dawe, S.; Smith, Susan; Williamson, Judy L.; Heisey, Dennis M.; Osorio, Jorge E.

2009-01-01

In previous studies, we demonstrated protection against plague in mice and prairie dogs using a raccoon pox (RCN) virus-vectored vaccine that expressed the F1 capsular antigen of Yersinia pestis. In order to improve vaccine efficacy, we have now constructed additional RCN-plague vaccines containing two different forms of the lcrV (V) gene, including full-length (Vfull) and a truncated form (V307). Mouse challenge studies with Y. pestis strain CO92 showed that vaccination with a combination of RCN-F1 and the truncated V construct (RCN-V307) provided the greatest improvement (P = 0.01) in protection against plague over vaccination with RCN-F1 alone. This effect was mediated primarily by anti-F1 and anti-V antibodies and both contributed independently to increased survival of vaccinated mice.

Food preference and feeding rhythm in red swamp crayfish Procambarus clarkii%克氏原螯虾的食物选择性及其摄食节律

Institute of Scientific and Technical Information of China (English)

徐增洪; 周鑫; 水燕

2012-01-01

Juvenile and adult red swamp crayfish (Procambarus clarkii) were reared in tanks (60 cm × 40 cm × 40 cm) at a rate of 20 individuals per tank and fed 5 aquatic plant species (Altemanthera philoxeroides, Eichhornia crassipes, Lesser duckweed Lemna minor, Elodea nultallii, and pondweed ValUsneria natans) to evaluate food I-tems and changes in food filling in stomach and intestines during day and night. In addition, the growth was compared in th crayfish reared in a paddyfield and fed three diets ( crayfish feedstuff with 30% protein, aquatic grasses and trash fish). The food in the intestine of the juvenile crayfish was found to be primarily comprised of zooplankton and phytoplankton. The adult crayfish was shown to have lower food preference, almost all of edible aquatic animals and plants, organic detritus, and artificial feed available in waters being consumed, and aquatic plants constituting their main food due to wide distribution, and easy ingesting. The feeding rhythm was observed during day and night in the crayfish culture pond, the two peaks at 8:00-10:00 and 19:00-22:00. There was significantly better growth in the adult crayfish fed Elodea nuttallii, Lesser duckweed and Vallisneria natans than that in the crayfish fed Altemanthera philoxeroides and Eichharnia crassipes(P0. 05) , even though the crayfish fed Lesser duckweed had slightly better growth than the crayfish fed Elodea nuUallii, and ValUsneria natans did. There was significant difference in daily weight gain rate in the juvenile crayfish fed lesser duckweed, Elodea nuttallii, Vallisneria natans, Altemanthera philoxeroides,Eichhornia crassipes(P<0.05). In the rice field, however, the crayfish fed trash fish was shown to have much better growth than that the crayfish fed pelleted food, and pelleted feedstuff combined with aquatic plants.%对克氏原螫虾Procambarus clarkii幼虾和成虾的胃及肠道内的食物组成和食物充塞度的昼夜变化规律进行了观察；在水族箱(60 cm

An encapsulated Yersinia pseudotuberculosis is a highly efficient vaccine against pneumonic plague.

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Anne Derbise

Full Text Available BACKGROUND: Plague is still a public health problem in the world and is re-emerging, but no efficient vaccine is available. We previously reported that oral inoculation of a live attenuated Yersinia pseudotuberculosis, the recent ancestor of Yersinia pestis, provided protection against bubonic plague. However, the strain poorly protected against pneumonic plague, the most deadly and contagious form of the disease, and was not genetically defined. METHODOLOGY AND PRINCIPAL FINDINGS: The sequenced Y. pseudotuberculosis IP32953 has been irreversibly attenuated by deletion of genes encoding three essential virulence factors. An encapsulated Y. pseudotuberculosis was generated by cloning the Y. pestis F1-encoding caf operon and expressing it in the attenuated strain. The new V674pF1 strain produced the F1 capsule in vitro and in vivo. Oral inoculation of V674pF1 allowed the colonization of the gut without lesions to Peyer's patches and the spleen. Vaccination induced both humoral and cellular components of immunity, at the systemic (IgG and Th1 cells and the mucosal levels (IgA and Th17 cells. A single oral dose conferred 100% protection against a lethal pneumonic plague challenge (33×LD(50 of the fully virulent Y. pestis CO92 strain and 94% against a high challenge dose (3,300×LD(50. Both F1 and other Yersinia antigens were recognized and V674pF1 efficiently protected against a F1-negative Y. pestis. CONCLUSIONS AND SIGNIFICANCE: The encapsulated Y. pseudotuberculosis V674pF1 is an efficient live oral vaccine against pneumonic plague, and could be developed for mass vaccination in tropical endemic areas to control pneumonic plague transmission and mortality.

Mortality risk factors show similar trends in modern and historic populations exposed to plague.

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Rubini, Mauro; Gualdi-Russo, Emanuela; Manzon, Vanessa S; Rinaldo, Natascia; Bianucci, Raffaella

2016-05-31

Plague has been responsible for two major historic pandemics (6th-8th century CE; 14th-19th century CE) and a modern one. The recent Malagasy plague outbreaks raised new concerns on the deadly potential of the plague-causing bacteria Yersinia pestis. Between September 2014 and April 2015, outbreaks of bubonic and pneumonic plague hit the Malagasy population. Two hundred and sixty-three cases, including 71 deaths, have been reported in 16 different districts with a case fatality rate of 27%. The scope of our study was to ascertain whether the risk factors for health in modern-day populations exposed to plague and in ancient populations that faced the two historic pandemics varied or remained substantially unaltered. The risk of mortality of the Malagasy population with those obtained from the reconstruction of three samples of European populations exposed to the historic pandemics was contrasted. The evidence shows that the risks of death are not uniform across age neither in modern nor in historic populations exposed to plague and shows precise concentrations in specific age groups (children between five and nine years of age and young adults). Although in the post-antibiotic era, the fatality rates have drastically reduced, both modern and historic populations were exposed to the same risk factors that are essentially represented by a low standard of environmental hygiene, poor nutrition, and weak health systems.

Hobbseus yalobushensis, a crayfish of intermittent streams: Biotic and habitat associations, life history characteristics, and new localities

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Susan B. Adams; Blake A. Davis; Darren A. Miller

2018-01-01

Hobbseus yalobushensis, the Yalobusha rivulet crayfish, is a species of conservation concern because it is known from only six localities in parts of three central Mississippi counties. No studies have focused on the species since its description in 1989. Our objectives were to: (1) identify additional H. yalobushensis...

Relative distribution and abundance of fishes and crayfish in 2010 and 2014 prior to saltcedar (Tamarix ssp.) removal in the Amargosa River Canyon, southeastern California

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Hereford, Mark E.

2016-07-22

The Amargosa River Canyon, located in the Mojave Desert of southeastern California, contains the longest perennial reach of the Amargosa River. Because of its diverse flora and fauna, it has been designated as an Area of Critical Environmental Concern and a Wild and Scenic River by the Bureau of Land Management. A survey of fishes conducted in summer 2010 indicated that endemic Amargosa River pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) were abundant and occurred throughout the Amargosa River Canyon. The 2010 survey reported non-native red swamp crayfish (Procambarus clarkii) and western mosquitofish (Gambusia affinis) captures were significantly higher, whereas pupfish captures were lower, in areas dominated by non-native saltcedar (Tamarix ssp.). Based on the 2010 survey, it was hypothesized that the invasion of saltcedar could result in a decrease in native species. In an effort to maintain and enhance native fish populations, the Bureau of Land Management removed saltcedar from a 1,550 meter reach of stream on the Amargosa River in autumn 2014 and autumn 2015. Prior to the removal of saltcedar, a survey of fishes and crayfish using baited minnow traps was conducted in the treatment reach to serve as a baseline for future comparisons with post-saltcedar removal surveys. During the 2014 survey, 1,073 pupfish and 960 speckled dace were captured within the treatment reach. Catch per unit effort of pupfish and speckled dace in the treatment reach was less in 2014 than in 2010, although differences could be owing to seasonal variation in capture probability. Non-native mosquitofish catch per unit effort decreased from 2010 to 2014; however, the catch per unit effort of crayfish increased from 2010 to 2014. Future monitoring efforts of this reach should be conducted at the same time period to account for potential seasonal fluctuations of abundance and distribution of fishes and crayfish. A more robust study design that

Wet climate and transportation routes accelerate spread of human plague

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Xu, Lei; Stige, Leif Chr.; Kausrud, Kyrre Linné; Ben Ari, Tamara; Wang, Shuchun; Fang, Xiye; Schmid, Boris V.; Liu, Qiyong; Stenseth, Nils Chr.; Zhang, Zhibin

2014-01-01

Currently, large-scale transmissions of infectious diseases are becoming more closely associated with accelerated globalization and climate change, but quantitative analyses are still rare. By using an extensive dataset consisting of date and location of cases for the third plague pandemic from 1772 to 1964 in China and a novel method (nearest neighbour approach) which deals with both short- and long-distance transmissions, we found the presence of major roads, rivers and coastline accelerated the spread of plague and shaped the transmission patterns. We found that plague spread velocity was positively associated with wet conditions (measured by an index of drought and flood events) in China, probably due to flood-driven transmission by people or rodents. Our study provides new insights on transmission patterns and possible mechanisms behind variability in transmission speed, with implications for prevention and control measures. The methodology may also be applicable to studies of disease dynamics or species movement in other systems. PMID:24523275

Invasion of an occupied niche by the crayfish Orconectes rusticus: potential importance of growth and mortality.

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Hill, Anna M; Sinars, Damon M; Lodge, David M

1993-06-01

We are exploring mechanisms of an invasion that contradicts the oft-cited generalization that species invade vacant niches. In northern Wisconsin lakes, the introduced crayfish Orconectes rusticus is replacing two ecologically similar resident congeners, O. virilis and O. propinquus. In laboratory experiments, we compared growth and mortality of individually maintained crayfish offered one of five ad libitum diets: invertebrates, macrophytes, dentritus, periphyton or all items combined. Mortality was highest for O. virilis and lowest for O. rusticus. Macrophyte diets yielded the highest mortality. All three species grew best on invertebrate and combination diets but grew little or not at all on diets of periphyton, detritus or macrophytes. O. rusticus and O. virilis grew more than O. propinquus. O. rusticus grew more quickly and/or was better able to survive overall than its congeners. Therefore, O. rusticus would probably have advantages over O. virilis and O. propinquus in competitive interactions, reproductive success and avoiding size-selective fish predation. Subtle interspecific differences may interact strongly with other ecological factors and contribute to the displacement of resident species from a well-occupied niche.

Biomagnification of some heavy and essential metals in sediments, fishes and crayfish from Ondo State coastal region, Nigeria

International Nuclear Information System (INIS)

Asaolu, S.S.; Olaofe, O.

2005-01-01

The bio magnifications levels of some essential (Fe, Zn, Cu) and toxic metals (Pb, Ni, Cd, Cr, Co, Mn) were determined in sediments, three kinds of fish (Oreochromis niloticus, Synodonthis sp., and Clarias gariepinus) and crayfish from the Ondo State coastal region. The metal bio magnification in the fish and crayfish was several times greater than in water, while that in the sediments was several thousand-folds greater than in both the organisms and water. Among the metals examined in water, Fe was the most abundant with average values of 146.7 and 74.3 mg/1, respectively, for wet and dry seasons, while Co was the least with average values of 2.4 and 1.6 mg/1. In the sediments, concentrations of Pb, Ni, Fe, Cr, Co and Mn in the wet season were relatively higher than those obtained for the dry season. Fe with an average of 50.9 mg/kg in C, gariepinus was the most abundant metal in the fish samples, while Cu with an average value of 0.3 mg/kg in O. niloticus was the least. The metal bio magnification for most of the metals for both seasons was found to vary widely from one location to the other. This was confirmed by the coefficient of variation that ranged from 31% to 144% and 29% to 130% in the wet and dry seasons, respectively. The present study has shown that fish, crayfish and sediments can be used to monitor the pollution level of metals in the Nigerian coastal water. (author)

Assessing plague risk and presence through surveys of small mammal flea communities

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M. M. Friggens; P. L. Ford; R. R. Parmenter; M. Boyden; K. Gage

2011-01-01

Plague, caused by the bacterium Yersinia pestis, remains a threat to human and wildlife populations in the Western United States (Gage and Kosoy 2005). Several rodent species have been implicated as important maintenance hosts in the U.S., including Peromyscus maniculatus and Dipodomys spp. Fleas are a critical component of plague foci (Gage and Kosoy 2005)....

Glutamatergic postsynaptic block by Pamphobeteus spider venoms in crayfish.

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Araque, A; Ferreira, W; Lucas, S; Buño, W

1992-01-31

The effects of toxins from venom glands of two south american spiders (Pamphobeteus platyomma and P. soracabae) on glutamatergic excitatory synaptic transmission were studied in the neuromuscular junction of the opener muscle of crayfish. The toxins selectively and reversibly blocked both excitatory postsynaptic currents and potentials in a dose-dependent manner. They also reversibly abolished glutamate-induced postsynaptic membrane depolarization. They had no effect on resting postsynaptic membrane conductance nor on postsynaptic voltage-gated currents. The synaptic facilitation and the frequency of miniature postsynaptic potentials were unaffected by the toxins, indicating that presynaptic events were not modified. Picrotoxin, a selective antagonist of the gamma-aminobutyric acid (GABA)A receptor, did not modify toxin effects. We conclude that both toxins specifically block the postsynaptic glutamate receptor-channel complex.

Concentrations of elements in fish fillets, fish muscle plugs, and crayfish from the 2007 Missouri Department of Conservation General Contaminant Monitoring Program

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May, Thomas W.; Walther, Michael J.; Brumbaugh, William G.; McKee, Michael J.

2009-01-01

This report presents the results of a contaminant monitoring survey conducted annually by the Missouri Department of Conservation to examine the levels of selected elemental contaminants in fish fillets, fish muscle plugs, and crayfish. Fillets of channel catfish (Ictalurus punctatus), bass (Micropterus salmoides, Micropterus dolomieu, Morone chrysops), walleye (Sander vitreus), common carp (Cyprinus carpio), lake sturgeon (Acipenser fulvescens), northern hog sucker (Hypentelium nigricans), and rainbow trout (Oncorhynchus mykiss) were collected from 21 sites as part of the Department's Fish Contaminant Monitoring Program. Long-pincered crayfish (Orconectes longidigitus) were collected from one site to assess trophic transfer of metals to fish. Fish muscle plugs were collected from smallmouth bass (Micropterus dolomieu) at two different locations from one site.

Low dimensional chaotic models for the plague epidemic in Bombay (1896–1911)

International Nuclear Information System (INIS)

Mangiarotti, Sylvain

2015-01-01

A plague epidemic broke out in Bombay in 1896 and became endemic. From 1905 to 1911, the epidemic was closely monitored by an Advisory Committee appointed to investigate the causes of the disease in any way. An impressive quantity of information was gathered, analyzed and published. Published data include records of the number of people who died from plague, and of the two main populations of rodents which were infected by plague in Bombay city. In the present paper, these data are revisited using a global modeling technique. This technique is applied to both single and multivariate observational time series. Several models are obtained for which a chaotic behavior can be observed. Obtaining such models proves that the dynamics of plague can be approximated by low-dimensional deterministic systems that can produce chaos. The multivariate models give a strong argument for interactive couplings between the epidemic and the epizootics of the two main species of rat. An interpretation of this coupling is given.

Concentrations of elements in fish fillets, fish muscle plugs, and crayfish from the 2011 Missouri Department of Conservation general contaminant monitoring program

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Brumbaugh, William G.; McKee, Michael J.

2013-01-01

This report presents the results of a contaminant monitoring survey conducted annually by the Missouri Department of Conservation to examine the levels of selected elemental contaminants in fish fillets, fish muscle plugs, and crayfish. Fillet samples of yellow bullhead (Ameiurus natalis), golden redhorse (Moxostoma erythrurum), longear sunfish (Lepomis megalotis), and channel catfish (Ictalurus punctatus) were collected from six sites as part of the Missouri Department of Conservation’s Fish Contaminant Monitoring Program. Fish dorsal muscle plugs were collected from largemouth bass (Micropterus salmoides) at eight of the sites, and crayfish from two sites. Following preparation and analysis of the samples, highlights of the data were as follows: cadmium and lead residues were most elevated in crayfish tissue samples from the Big River at Cherokee Landing, with 1 to 8 micrograms per gram dry weight and 22 to 45 micrograms per gram dry weight, respectively. Some dorsal muscle plugs from largemouth bass collected from Clearwater Lake, Lake St. Louis, Noblett Lake, Hazel Creek Lake, and Harrison County Lake contained mercury residues (1.7 to 4.7 micrograms per gram dry weight) that exceeded the U.S. Environmental Protection Agency Water Quality Criterion of 1.5 micrograms per gram dry weight of fish tissue (equivalent to 0.30 micrograms per gram wet weight).

Habitat use and population structure of the invasive red swamp crayfish Procambarus clarkii (Girard, 1852 in a protected area in northern Italy

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Donato Roberta

2018-01-01

Full Text Available The red swamp crayfish Procambarus clarkii is one of the most invasive alien species in Europe and included in the list of invasive species of Union concern. We describe for the first time some life-history traits of a red swamp crayfish population in the Nature Reserve of the Lago di Candia (Italy. We investigated (1 preferences of this species for specific environmental features on the banks of the lake, and (2 differences in size, sex ratio, and condition index between individuals caught in lake and marsh. Moreover, we compared sampling effort and the features of individuals caught in the lake, for two sampling seasons in 2014 and 2015. Findings indicated that the population was well established, and the marsh seemed to have better conditions for growth of individuals than the lake. Accordingly, continuity of riparian vegetation, opportunity to dig burrows, and trophic resource availability seems to facilitate the proliferation of the crayfish in the lake. Our study demonstrated that massive removal efforts over the whole active period of the species and more than one year of trapping are necessary to increase the controlling activities' success. This study could have important implications for further population management projects directed at biodiversity conservation in the area.

Plague epizootic cycles in Central Asia.

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Reijniers, Jonas; Begon, Mike; Ageyev, Vladimir S; Leirs, Herwig

2014-06-01

Infection thresholds, widely used in disease epidemiology, may operate on host abundance and, if present, on vector abundance. For wildlife populations, host and vector abundances often vary greatly across years and consequently the threshold may be crossed regularly, both up- and downward. Moreover, vector and host abundances may be interdependent, which may affect the infection dynamics. Theory predicts that if the relevant abundance, or combination of abundances, is above the threshold, then the infection is able to spread; if not, it is bound to fade out. In practice, though, the observed level of infection may depend more on past than on current abundances. Here, we study the temporal dynamics of plague (Yersinia pestis infection), its vector (flea) and its host (great gerbil) in the PreBalkhash region in Kazakhstan. We describe how host and vector abundances interact over time and how this interaction drives the dynamics of the system around the infection threshold, consequently affecting the proportion of plague-infected sectors. We also explore the importance of the interplay between biological and detectability delays in generating the observed dynamics.

ANNUAL ACTIVITY OF THE NOBLE CRAYFISH (ASTACUS ASTACUS) IN THE ORLJAVA RIVER (CROATIA)

OpenAIRE

FALLER M.; MAGUIRE I.; KLOBUČAR G.

2006-01-01

We studied the annual activity of the noble crayfish (Astacus astacus) at three sites along the Orljava River, in the continental part of Croatia, between August 2003 and September 2004. Each site represented the typical characteristics of the upper, middle and lower section of the river (5, 24 and 37 km from the spring, respectively). The biggest population size was recorded on the most upstream site, with greatest structural variability of bottom, high biotic index, and the lowest mean wate...

Rapid and sensitive detection of Yersinia pestis using amplification of plague diagnostic bacteriophages monitored by real-time PCR.

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Kirill V Sergueev

Full Text Available BACKGROUND: Yersinia pestis, the agent of plague, has caused many millions of human deaths and still poses a serious threat to global public health. Timely and reliable detection of such a dangerous pathogen is of critical importance. Lysis by specific bacteriophages remains an essential method of Y. pestis detection and plague diagnostics. METHODOLOGY/PRINCIPAL FINDINGS: The objective of this work was to develop an alternative to conventional phage lysis tests--a rapid and highly sensitive method of indirect detection of live Y. pestis cells based on quantitative real-time PCR (qPCR monitoring of amplification of reporter Y. pestis-specific bacteriophages. Plague diagnostic phages phiA1122 and L-413C were shown to be highly effective diagnostic tools for the detection and identification of Y. pestis by using qPCR with primers specific for phage DNA. The template DNA extraction step that usually precedes qPCR was omitted. phiA1122-specific qPCR enabled the detection of an initial bacterial concentration of 10(3 CFU/ml (equivalent to as few as one Y. pestis cell per 1-microl sample in four hours. L-413C-mediated detection of Y. pestis was less sensitive (up to 100 bacteria per sample but more specific, and thus we propose parallel qPCR for the two phages as a rapid and reliable method of Y. pestis identification. Importantly, phiA1122 propagated in simulated clinical blood specimens containing EDTA and its titer rise was detected by both a standard plating test and qPCR. CONCLUSIONS/SIGNIFICANCE: Thus, we developed a novel assay for detection and identification of Y. pestis using amplification of specific phages monitored by qPCR. The method is simple, rapid, highly sensitive, and specific and allows the detection of only live bacteria.

A High-Coverage Yersinia pestis Genome from a Sixth-Century Justinianic Plague Victim.

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Feldman, Michal; Harbeck, Michaela; Keller, Marcel; Spyrou, Maria A; Rott, Andreas; Trautmann, Bernd; Scholz, Holger C; Päffgen, Bernd; Peters, Joris; McCormick, Michael; Bos, Kirsten; Herbig, Alexander; Krause, Johannes

2016-11-01

The Justinianic Plague, which started in the sixth century and lasted to the mid eighth century, is thought to be the first of three historically documented plague pandemics causing massive casualties. Historical accounts and molecular data suggest the bacterium Yersinia pestis as its etiological agent. Here we present a new high-coverage (17.9-fold) Y. pestis genome obtained from a sixth-century skeleton recovered from a southern German burial site close to Munich. The reconstructed genome enabled the detection of 30 unique substitutions as well as structural differences that have not been previously described. We report indels affecting a lacl family transcription regulator gene as well as nonsynonymous substitutions in the nrdE, fadJ, and pcp genes, that have been suggested as plague virulence determinants or have been shown to be upregulated in different models of plague infection. In addition, we identify 19 false positive substitutions in a previously published lower-coverage Y. pestis genome from another archaeological site of the same time period and geographical region that is otherwise genetically identical to the high-coverage genome sequence reported here, suggesting low-genetic diversity of the plague during the sixth century in rural southern Germany. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Findings of bacterial microflora in piglets infected with conventional swine plague

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Prodanov Jasna

2002-01-01

Full Text Available Piglets infected with the conventional swine plague virus as a result of secondary bacterial infections sometimes show an insufficiently clear clinical and pathoanatomical picture, which is why the very procedure of diagnosis is complex and the final diagnosis unreliable. That is why these investigations were aimed at examining the presence of bacterial microflora in diseased and dead pilgets which were found to have the viral antigen for CSP using the fluorescent antibody technique, in cases where the pathomorphological finding was not characteristic for conventional swine plague. Autopsies of dead piglets most often showed changes in the digestive tract and lungs, with resulting technopathy and diseases of infective nature. Such findings on knowledge of a present bacterial microflora are especially important in cases when conventional swine plague is controlled on farms and an announcement that the disease has been contained is in the offing.

Dissociation of Tissue Destruction and Bacterial Expansion during Bubonic Plague.

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Françoise Guinet

2015-10-01

Full Text Available Activation and/or recruitment of the host plasmin, a fibrinolytic enzyme also active on extracellular matrix components, is a common invasive strategy of bacterial pathogens. Yersinia pestis, the bubonic plague agent, expresses the multifunctional surface protease Pla, which activates plasmin and inactivates fibrinolysis inhibitors. Pla is encoded by the pPla plasmid. Following intradermal inoculation, Y. pestis has the capacity to multiply in and cause destruction of the lymph node (LN draining the entry site. The closely related, pPla-negative, Y. pseudotuberculosis species lacks this capacity. We hypothesized that tissue damage and bacterial multiplication occurring in the LN during bubonic plague were linked and both driven by pPla. Using a set of pPla-positive and pPla-negative Y. pestis and Y. pseudotuberculosis strains in a mouse model of intradermal injection, we found that pPla is not required for bacterial translocation to the LN. We also observed that a pPla-cured Y. pestis caused the same extensive histological lesions as the wild type strain. Furthermore, the Y. pseudotuberculosis histological pattern, characterized by infectious foci limited by inflammatory cell infiltrates with normal tissue density and follicular organization, was unchanged after introduction of pPla. However, the presence of pPla enabled Y. pseudotuberculosis to increase its bacterial load up to that of Y. pestis. Similarly, lack of pPla strongly reduced Y. pestis titers in LNs of infected mice. This pPla-mediated enhancing effect on bacterial load was directly dependent on the proteolytic activity of Pla. Immunohistochemistry of Pla-negative Y. pestis-infected LNs revealed extensive bacterial lysis, unlike the numerous, apparently intact, microorganisms seen in wild type Y. pestis-infected preparations. Therefore, our study demonstrates that tissue destruction and bacterial survival/multiplication are dissociated in the bubo and that the primary action of Pla

Socio-epidemiological determinants of 2002 plague outbreak in Himachal Pradesh, India: a qualitative study

Science.gov (United States)

2014-01-01

Background This qualitative investigation was conducted to determine the socio-epidemiological factors related to the plague outbreak (2002) in Himachal Pradesh (HP), India. Methods The data for socio-epidemiological factors related to the plague outbreak (2002) in HP was obtained from residents through 150 in-depth Interviews (IDI) and 30 Focus Group Discussions (FGD) during six visits (from May 2011 to April 2012) by the research team. Natives, health officials and the nomadic population were interviewed. According to their opinion and viewpoints data was collected and their lifestyle and hunting practices were studied in detail. Tape recorders were used during various FGDs and IDIs. The interviews and FGDs were later transcribed and coded. In-depth analysis of the recorded data was done using an inductive thematic analysis approach. Results The study reports that the outbreak in 2002 in a few villages of Himachal Pradesh was that of plague and it occurred by the contact of an index case with wild animals after hunting and de-skinning. The first wave of plague transmission which took 16 lives of residents was followed by a second wave of transmission in a ward of a tertiary care hospital where one visitor acquired it from relatives of the index case and succumbed. The life-style practices of residents (hunting behavior, long stay in caves and jungles, overcrowding in houses, poor hygiene and sanitation, belief in ‘God’ and faith healers for cure of diseases) was optimal for the occurrence and rapid spread of such a communicable disease. The man-rodent contact is intensified due to the practice of hunting in such a rodent-ridden environment. The residents harbor a strong belief that plague occurs due to the wrath of gods. Various un-reported outbreaks of plague were also observed by officials, residents and old folk. The persistence of plague in HP is favoured by its hilly terrain, inaccessible areas, inclement weather (snow) in winters, unhygienic lifestyle

News Reports about Health: Between Heroes and Plagues

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Acianela Montes de Oca

2013-12-01

Full Text Available This research characterizes news reports published in the health sections of two newspapers, El Nacional and El Universal, from 1996 to 2006 from the perspective of the myths. Mytheme analysis and rhetorical figures show that myths more frecuently used were The Hero, The Progress, The Plague and Panacea. From the analysis we concluded that the texts of the health sections of analyzed newspapers show a dangerous world (stalked by The Plague that only the Hero (the doctor can face. Science, technology, modernity, health, The Progress, Panacea, seem a gift rather than a human conquest. If we accept the premise that the myths act unify social representations and introduce a single meaning to the future, these stories express a look of helplessness and uncertainty in illness and risk.

Interdisciplinarity to reconstruct historical introductions: solving the status of cryptogenic crayfish.

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Clavero, Miguel; Nores, Carlos; Kubersky-Piredda, Susanne; Centeno-Cuadros, Alejandro

2016-11-01

Anciently introduced species can be confounded with native species because introduction pre-dates the first species inventories or because of the loss of the collective memory of the introductions. The term 'cryptogenic species' denotes species of unknown or unclear status (native versus non-native) in a given territory, and disciplinary approaches are often insufficient for solving their true status. Here, we follow an integrative, multidisciplinary approach to solve the status of a cryptogenic species, proposing that building on evidence from multiple disciplines can produce robust and clarifying insights. We undertook an exhaustive review of information on a putatively native crayfish (Austropotamobius italicus) in Spain. The reviewed information included taxonomy, genetics and phylogeography, history, archaeology, linguistics, biogeography, ecology, symbiotic organisms and even gastronomy and pharmacy. The knowledge produced by different scientific disciplines converges to indicate that A. italicus is a non-native species in Spain. Historical documents even identify the first introduction event: crayfish were shipped from Italy to Spain in 1588 as a diplomatic gift from Francesco I de' Medici to King Philip II of Spain. Previous discussions on the status of A. italicus focussed on inconclusive and often confusing genetic results and excluded the rich and clarifying evidence available from other approaches and disciplines. Interdisciplinarity is an often-invoked but rarely implemented practice in an academic environment that increasingly promotes narrow-focussed specialization. Our review shows that the integration of disciplines can surpass disciplinary approaches in solving scientific controversies. Our results have straightforward implications for strategies to conserve biological diversity in Spain and Europe, urging a debate on the appropriateness of devoting conservation efforts to non-native species. © 2015 Cambridge Philosophical Society.

Heavy metals bioaccumulation in selected tissues of red swamp crayfish: An easy tool for monitoring environmental contamination levels.

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Goretti, E; Pallottini, M; Ricciarini, M I; Selvaggi, R; Cappelletti, D

2016-07-15

In this paper we explored the heavy metal bioaccumulation (Cd, Cu, Pb and Zn) in Procambarus clarkii, a crayfish recently suggested as a potential bioindicator for metals pollution in freshwater systems. The present study is focused on crayfishes populations caught in a heavily polluted industrial and in a reference sites (Central Italy), though the results are generalized with a thorough analysis of literature metadata. In agreement with the literature, the hepatopancreas (Hep, detoxification tissues) of the red swamp crayfish showed a higher concentration of heavy metals in comparison to the abdominal muscle (AbM, not detoxification tissues) in the sites under scrutiny. Hep/AbM concentration ratio was dependent on the specific metal investigated and on its sediment contamination level. Specifically we found that Hep/AbM ratio decreases as follows: Cd (11.7)>Cu (5.5)>Pb (3.6)>Zn (1.0) and Pb (4.34)>Cd (3.66)>Zn (1.69)>Cu (0.87) for the industrial and reference sites, respectively. The analysis of our bioaccumulation data as well as of literature metadata allowed to elaborate a specific contamination index (Toxic Contamination Index, TCI), dependent only on the bioaccumulation data of hepatopancreas and abdominal muscle. In the industrial site, TCI expressed values much higher than the unit for Cd and Cu, confirming that these metals were the main contaminants; in contrast for lower levels of heavy metals, as those observed in the reference site for Cu, Zn and Pb, the index provided values below unit. TCI is proposed as a useful and easy tool to assess the toxicity level of contaminated sites by heavy metals in the environmental management. Copyright © 2016. Published by Elsevier B.V.

The innate immune response may be important for surviving plague in wild Gunnison's prairie dogs

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Busch, Joseph D.; Van Andel, Roger; Stone, Nathan E.; Cobble, Kacy R.; Nottingham, Roxanne; Lee, Judy; VerSteeg, Michael; Corcoran, Jeff; Cordova, Jennifer; Van Pelt, William E.; Shuey, Megan M.; Foster, Jeffrey T.; Schupp, James M.; Beckstrom-Sternberg, Stephen; Beckstrom-Sternberg, James; Keim, Paul; Smith, Susan; Rodriguez-Ramos, Julia; Williamson, Judy L.; Rocke, Tonie E.; Wagner, David M.

2013-01-01

Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis, with ≥99% mortality reported from multiple studies of plague epizootics. A colony of Gunnison's prairie dogs (Cynomys gunnisoni) in the Aubrey Valley (AV) of northern Arizona appears to have survived several regional epizootics of plague, whereas nearby colonies have been severely affected by Y. pestis. To examine potential mechanisms accounting for survival in the AV colony, we conducted a laboratory Y. pestis challenge experiment on 60 wild-caught prairie dogs from AV and from a nearby, large colony with frequent past outbreaks of plague, Espee (n = 30 per colony). Test animals were challenged subcutaneously with the fully virulent Y. pestis strain CO92 at three doses: 50, 5,000, and 50,000 colony-forming units (cfu); this range is lethal in black-tailed prairie dogs (Cynomys ludovicianus). Contrary to our expectations, only 40% of the animals died. Although mortality trended higher in the Espee colony (50%) compared with AV (30%), the differences among infectious doses were not statistically significant. Only 39% of the survivors developed moderate to high antibody levels to Y. pestis, indicating that mechanisms other than humoral immunity are important in resistance to plague. The ratio of neutrophils to lymphocytes was not correlated with plague survival in this study. However, several immune proteins with roles in innate immunity (VCAM-1, CXCL-1, and vWF) were upregulated during plague infection and warrant further inquiry into their role for protection against this disease. These results suggest plague resistance exists in wild populations of the Gunnison's prairie dog and provide important directions for future studies.

Neuromodulation of reciprocal glutamatergic inhibition between antagonistic motoneurons by 5-hydroxytryptamine (5-HT) in crayfish walking system.

Science.gov (United States)

Pearlstein, E; Clarac, F; Cattaert, D

1998-01-23

In an in vitro preparation of the crayfish thoracic locomotor system, paired intracellular recordings were performed from antagonistic depressor (Dep) and levator (Lev) motoneurons (MNs) that control the second joint of walking legs. Connections between these two groups of MNs consist mainly of inhibitory connections and weak electrotonic synapses. Injection of depolarizing current into a Lev MN results in a hyperpolarization in a Dep MN, and vice versa. This reciprocal glutamatergic inhibition, is not changed in the presence of the sodium channel blocker tetrodotoxin (TTX) and therefore is likely supported by a direct connection between MNs. By contrast, reciprocal inhibition is largely reduced in the presence of 5-hydroxytryptamine (5-HT; 10 microM). Direct micro-application of glutamate pressure-ejected close to an intracellularly recorded MN, evoked an inhibitory response in that MN, accompanied by a decrease of input resistance. These two effects were dramatically reduced in the presence of 5-HT. Thus 5-HT could be involved in mechanisms of dynamic reconfigurations of the neural network controlling leg movements in crayfish.

Model-based analysis of an outbreak of bubonic plague in Cairo in 1801.

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Didelot, Xavier; Whittles, Lilith K; Hall, Ian

2017-06-01

Bubonic plague has caused three deadly pandemics in human history: from the mid-sixth to mid-eighth century, from the mid-fourteenth to the mid-eighteenth century and from the end of the nineteenth until the mid-twentieth century. Between the second and the third pandemics, plague was causing sporadic outbreaks in only a few countries in the Middle East, including Egypt. Little is known about this historical phase of plague, even though it represents the temporal, geographical and phylogenetic transition between the second and third pandemics. Here we analysed in detail an outbreak of plague that took place in Cairo in 1801, and for which epidemiological data are uniquely available thanks to the presence of medical officers accompanying the Napoleonic expedition into Egypt at that time. We propose a new stochastic model describing how bubonic plague outbreaks unfold in both rat and human populations, and perform Bayesian inference under this model using a particle Markov chain Monte Carlo. Rat carcasses were estimated to be infectious for approximately 4 days after death, which is in good agreement with local observations on the survival of infectious rat fleas. The estimated transmission rate between rats implies a basic reproduction number R 0 of approximately 3, causing the collapse of the rat population in approximately 100 days. Simultaneously, the force of infection exerted by each infected rat carcass onto the human population increases progressively by more than an order of magnitude. We also considered human-to-human transmission via pneumonic plague or human specific vectors, but found this route to account for only a small fraction of cases and to be significantly below the threshold required to sustain an outbreak. © 2017 The Author(s).

Age at vaccination may influence response to sylvatic plague vaccine (SPV) in Gunnison’s prairie dogs (Cynomys gunnisoni)

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Rocke, Tonie E.; Tripp, Daniel W.; Lorenzsonn, Faye; Falendysz, Elizabeth A.; Smith, Susan; Williamson, Judy L.; Abbott, Rachel C.

2015-01-01

Gunnison’s prairie dogs (Cynomys gunnisoni) have been considered at greater risk from Yersinia pestis (plague) infection in the montane portion of their range compared to populations at lower elevations, possibly due to factors related to flea transmission of the bacteria or greater host susceptibility. To test the latter hypothesis and determine whether vaccination against plague with an oral sylvatic plague vaccine (SPV) improved survival, we captured prairie dogs from a C. g. gunnisoni or “montane” population and a C. g. zuniensis or “prairie” population for vaccine efficacy and challenge studies. No differences (P = 0.63) were found in plague susceptibility in non-vaccinated animals between these two populations; however, vaccinates from the prairie population survived plague challenge at significantly higher rates (P age, as the prairie group was much younger on average than the montane group. Vaccinates that were juveniles or young adults survived plague challenge at a much higher rate than adults (P ages. These results suggest that host susceptibility is probably not related to the assumed greater risk from plague in the C. g. gunnisoni or “montane” populations of Gunnison’s prairie dogs, and that SPV could be a useful plague management tool for this species, particularly if targeted at younger cohorts.

Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

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Miarinjara, Adélaïde; Boyer, Sébastien

2016-02-01

Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

Identification of duck plague virus by polymerase chain reaction

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Hansen, W.R.; Brown, Sean E.; Nashold, S.W.; Knudson, D.L.

1999-01-01

A polymerase chain reaction (PCR) assay was developed for detecting duck plague virus. A 765-bp EcoRI fragment cloned from the genome of the duck plague vaccine (DP-VAC) virus was sequenced for PCR primer development. The fragment sequence was found by GenBank alignment searches to be similar to the 3a?? ends of an undefined open reading frame and the gene for DNA polymerase protein in other herpesviruses. Three of four primer sets were found to be specific for the DP-VAC virus and 100% (7/7) of field isolates but did not amplify DNA from inclusion body disease of cranes virus. The specificity of one primer set was tested with genome templates from other avian herpesviruses, including those from a golden eagle, bald eagle, great horned owl, snowy owl, peregrine falcon, prairie falcon, pigeon, psittacine, and chicken (infectious laryngotracheitis), but amplicons were not produced. Hence, this PCR test is highly specific for duck plague virus DNA. Two primer sets were able to detect 1 fg of DNA from the duck plague vaccine strain, equivalent to five genome copies. In addition, the ratio of tissue culture infectious doses to genome copies of duck plague vaccine virus from infected duck embryo cells was determined to be 1:100, making the PCR assay 20 times more sensitive than tissue culture for detecting duck plague virus. The speed, sensitivity, and specificity of this PCR provide a greatly improved diagnostic and research tool for studying the epizootiology of duck plague. /// Se desarroll?? una prueba de reacci??n en cadena por la polimerasa para detectar el virus de la peste del pato. Un fragmento EcoRI de 765 pares de bases clonado del genoma del virus vacunal de la peste del pato fue secuenciado para la obtenci??n de los iniciadores de la prueba de la reacci??n en cadena por la polimerasa. En investigaciones de alineaci??n en el banco de genes ('GenBank') se encontr?? que la secuencia del fragmento era similar a los extremos 3a?? de un marco de lectura abierto

Adjunctive Corticosteroid Treatment Against Yersinia pestis Improves Bacterial Clearance, Immunopathology, and Survival in the Mouse Model of Bubonic Plague.

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Levy, Yinon; Vagima, Yaron; Tidhar, Avital; Zauberman, Ayelet; Aftalion, Moshe; Gur, David; Fogel, Itay; Chitlaru, Theodor; Flashner, Yehuda; Mamroud, Emanuelle

2016-09-15

Plague is initiated by Yersinia pestis, a highly virulent bacterial pathogen. In late stages of the infection, bacteria proliferate extensively in the internal organs despite the massive infiltration of neutrophils. The ineffective inflammatory response associated with tissue damage may contribute to the low efficacy of antiplague therapies during late stages of the infection. In the present study, we address the possibility of improving therapeutic efficacy by combining corticosteroid administration with antibody therapy in the mouse model of bubonic plague. Mice were subcutaneously infected with a fully virulent Y. pestis strain and treated at progressive stages of the disease with anti-Y. pestis antibodies alone or in combination with the corticosteroid methylprednisolone. The addition of methylprednisolone to antibody therapy correlated with improved mouse survival, a significant decrease in the amount of neutrophils and matrix metalloproteinase 9 in the tissues, and the mitigation of tissue damage. Interestingly, the combined treatment led to a decrease in the bacterial loads in infected organs. Corticosteroids induce an unexpectedly effective antibacterial response apart from their antiinflammatory properties, thereby improving treatment efficacy. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Host resistance, population structure and the long-term persistence of bubonic plague: contributions of a modelling approach in the Malagasy focus.

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Fanny Gascuel

Full Text Available Although bubonic plague is an endemic zoonosis in many countries around the world, the factors responsible for the persistence of this highly virulent disease remain poorly known. Classically, the endemic persistence of plague is suspected to be due to the coexistence of plague resistant and plague susceptible rodents in natural foci, and/or to a metapopulation structure of reservoirs. Here, we test separately the effect of each of these factors on the long-term persistence of plague. We analyse the dynamics and equilibria of a model of plague propagation, consistent with plague ecology in Madagascar, a major focus where this disease is endemic since the 1920s in central highlands. By combining deterministic and stochastic analyses of this model, and including sensitivity analyses, we show that (i endemicity is favoured by intermediate host population sizes, (ii in large host populations, the presence of resistant rats is sufficient to explain long-term persistence of plague, and (iii the metapopulation structure of susceptible host populations alone can also account for plague endemicity, thanks to both subdivision and the subsequent reduction in the size of subpopulations, and extinction-recolonization dynamics of the disease. In the light of these results, we suggest scenarios to explain the localized presence of plague in Madagascar.

Host Resistance, Population Structure and the Long-Term Persistence of Bubonic Plague: Contributions of a Modelling Approach in the Malagasy Focus

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Gascuel, Fanny; Choisy, Marc; Duplantier, Jean-Marc; Débarre, Florence; Brouat, Carine

2013-01-01

Although bubonic plague is an endemic zoonosis in many countries around the world, the factors responsible for the persistence of this highly virulent disease remain poorly known. Classically, the endemic persistence of plague is suspected to be due to the coexistence of plague resistant and plague susceptible rodents in natural foci, and/or to a metapopulation structure of reservoirs. Here, we test separately the effect of each of these factors on the long-term persistence of plague. We analyse the dynamics and equilibria of a model of plague propagation, consistent with plague ecology in Madagascar, a major focus where this disease is endemic since the 1920s in central highlands. By combining deterministic and stochastic analyses of this model, and including sensitivity analyses, we show that (i) endemicity is favoured by intermediate host population sizes, (ii) in large host populations, the presence of resistant rats is sufficient to explain long-term persistence of plague, and (iii) the metapopulation structure of susceptible host populations alone can also account for plague endemicity, thanks to both subdivision and the subsequent reduction in the size of subpopulations, and extinction-recolonization dynamics of the disease. In the light of these results, we suggest scenarios to explain the localized presence of plague in Madagascar. PMID:23675291

Plague and the gallium scan: case report

International Nuclear Information System (INIS)

Stahly, T.L.; Shoop, J.D.

1975-01-01

Inflammation in the right axillary lymph nodes and the meninges was detected by 67 Ga-citrate scans in an 11-year-old boy with Yersinia pestis infection. This case provides another example of 67 Ga localizing to areas of infection, indicating potential utility in future cases of bubonic plague

Ten years of surveillance of the Yulong plague focus in China and the molecular typing and source tracing of the isolates.

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Wang, Peng; Shi, Liyuan; Zhang, Fuxin; Guo, Ying; Zhang, Zhikai; Tan, Hongli; Cui, Zhigang; Ding, Yibo; Liang, Ying; Liang, Yun; Yu, Dongzheng; Xu, Jianguo; Li, Wei; Song, Zhizhong

2018-03-01

Plague, caused by Yersinia pestis, was classified as a reemerging infectious disease by the World Health Organization. The five human pneumonic plague cases in Yulong County in 2005 gave rise to the discovery of a Yulong plague focus in Yunnan province, China. Thereafter, continuous wild rodent plague (sylvatic plague) was identified as the main plague reservoir of this focus. In this study, the epizootics in Yulong focus were described, and three molecular typing methods, including the different region (DFR) analysis, clustered regularly interspaced short palindromic repeats (CRISPRs), and the multiple-locus variable number of tandem repeats (VNTR) analysis (MLVA) (14+12), were used for the molecular typing and source tracing of Y. pestis isolates in the Yulong plague focus. Simultaneously, several isolates from the vicinity of Yunnan were used as controls. The results showed that during the 10-year period from 2006 to 2016, an animal plague epidemic occurred in 6 of those years, and 5 villages underwent an animal plague epidemic within a 30-km2 area of the Yulong plague focus. Searching for dead mice was the most effective monitoring method in this plague focus. No positive sample has been found in 6937 captured live rodents thus far, suggesting that the virulence of strains in the Yulong plague focus is stronger and the survival time of mice is shorter after infection. Strains from Lijiang, Sichuan and Tibet were of the same complex based on a typing analysis of DFR and CRISPR. The genetic relationship of Y. pestis illustrated by MLVA "14+12" demonstrates that Tibet and Sichuan strains evolved from the strains 1.IN2 (Qinghai, 1970 and Tibet, 1976), and Lijiang strains are closer to Batang strains (Batang County in Sichuan province, 2011, Himalaya marmot plague foci) in terms of genetic or phylogenic relationships. In conclusion, we have a deeper understanding of this new plague focus throughout this study, which provides a basis for effective prevention and

Dangers of noncritical use of historical plague databases

NARCIS (Netherlands)

Roosen, J.; Curtis, D.R.

2018-01-01

Researchers have published several articles using historical data sets on plague epidemics using impressive digital databases that contain thousands of recorded outbreaks across Europe over the past several centuries. Through the digitization of preexisting data sets, scholars have unprecedented

Distribution and establishment of the alien Australian redclaw crayfish, Cherax quadricarinatus, in South Africa and Swaziland

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Ana L. Nunes

2017-04-01

Full Text Available Background The Australian redclaw crayfish (Cherax quadricarinatus, von Martens, is native to Australasia, but has been widely translocated around the world due to aquaculture and aquarium trade. Mostly as a result of escape from aquaculture facilities, this species has established extralimital populations in Australia and alien populations in Europe, Asia, Central America and Africa. In South Africa, C. quadricarinatus was first sampled from the wild in 2002 in the Komati River, following its escape from an aquaculture facility in Swaziland, but data on the current status of its populations are not available. Methods To establish a better understanding of its distribution, rate of spread and population status, we surveyed a total of 46 sites in various river systems in South Africa and Swaziland. Surveys were performed between September 2015 and August 2016 and involved visual observations and the use of collapsible crayfish traps. Results Cherax quadricarinatus is now present in the Komati, Lomati, Mbuluzi, Mlawula and Usutu rivers, and it was also detected in several off-channel irrigation impoundments. Where present, it was generally abundant, with populations having multiple size cohorts and containing ovigerous females. In the Komati River, it has spread more than 112 km downstream of the initial introduction point and 33 km upstream of a tributary, resulting in a mean spread rate of 8 km year−1 downstream and 4.7 km year−1 upstream. In Swaziland, estimated downstream spread rate might reach 14.6 km year−1. Individuals were generally larger and heavier closer to the introduction site, which might be linked to juvenile dispersal. Discussion These findings demonstrate that C. quadricarinatus is established in South Africa and Swaziland and that the species has spread, not only within the river where it was first introduced, but also between rivers. Considering the strong impacts that alien crayfish usually have on invaded ecosystems

Evaluation of Yersinia pestis transmission pathways for sylvatic plague in prairie dog populations in the western U.S.

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Richgels, Katherine L. D.; Russell, Robin E.; Bron, Gebbiena; Rocke, Tonie E.

2016-01-01

Sylvatic plague, caused by the bacterium Yersinia pestis, is periodically responsible for large die-offs in rodent populations that can spillover and cause human mortalities. In the western US, prairie dog populations experience nearly 100% mortality during plague outbreaks, suggesting that multiple transmission pathways combine to amplify plague dynamics. Several alternate pathways in addition to flea vectors have been proposed, such as transmission via direct contact with bodily fluids or inhalation of infectious droplets, consumption of carcasses, and environmental sources of plague bacteria, such as contaminated soil. However, evidence supporting the ability of these proposed alternate pathways to trigger large-scale epizootics remains elusive. Here we present a short review of potential plague transmission pathways and use an ordinary differential equation model to assess the contribution of each pathway to resulting plague dynamics in black-tailed prairie dogs (Cynomys ludovicianus) and their fleas (Oropsylla hirsuta). Using our model, we found little evidence to suggest that soil contamination was capable of producing plague epizootics in prairie dogs. However, in the absence of flea transmission, direct transmission, i.e., contact with bodily fluids or inhalation of infectious droplets, could produce enzootic dynamics, and transmission via contact with or consumption of carcasses could produce epizootics. This suggests that these pathways warrant further investigation.

Comparing bacterial community composition between healthy and white plague-like disease states in Orbicella annularis using PhyloChip™ G3 microarrays

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Kellogg, Christina A.; Piceno, Yvette M.; Tom, Lauren M.; DeSantis, Todd Z.; Gray, Michael A.; Zawada, David G.; Andersen, Gary L.

2013-01-01

Coral disease is a global problem. Diseases are typically named or described based on macroscopic changes, but broad signs of coral distress such as tissue loss or discoloration are unlikely to be specific to a particular pathogen. For example, there appear to be multiple diseases that manifest the rapid tissue loss that characterizes ‘white plague.’ PhyloChip™ G3 microarrays were used to compare the bacterial community composition of both healthy and white plague-like diseased corals. Samples of lobed star coral (Orbicella annularis, formerly of the genus Montastraea [1]) were collected from two geographically distinct areas, Dry Tortugas National Park and Virgin Islands National Park, to determine if there were biogeographic differences between the diseases. In fact, all diseased samples clustered together, however there was no consistent link to Aurantimonas coralicida, which has been described as the causative agent of white plague type II. The microarrays revealed a large amount of bacterial heterogeneity within the healthy corals and less diversity in the diseased corals. Gram-positive bacterial groups (Actinobacteria, Firmicutes) comprised a greater proportion of the operational taxonomic units (OTUs) unique to healthy samples. Diseased samples were enriched in OTUs from the families Corynebacteriaceae, Lachnospiraceae, Rhodobacteraceae, and Streptococcaceae. Much previous coral disease work has used clone libraries, which seem to be methodologically biased toward recovery of Gram-negative bacterial sequences and may therefore have missed the importance of Gram-positive groups. The PhyloChip™ data presented here provide a broader characterization of the bacterial community changes that occur within Orbicella annularis during the shift from a healthy to diseased state.

Mitochondrial DNA provides evidence of a double origin for the stone crayfish Austropotamobius torrentium in the Elbe basin

Czech Academy of Sciences Publication Activity Database

Petrusek, A.; Pešek, P.; Leština, Dan; Martin, P.; Fischer, D.; Kozák, P.; Vlach, P.

2017-01-01

Roč. 62, JAN 01 (2017), s. 77-83 ISSN 0075-9511 Institutional support: RVO:60077344 Keywords : stone crayfish * Austropotamobius torrentium * Elbe basin Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 1.427, year: 2016 https://www.sciencedirect.com/science/article/pii/S0075951116300901

Low cost, low tech SNP genotyping tools for resource-limited areas: Plague in Madagascar as a model.

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Cedar L Mitchell

2017-12-01

Full Text Available Genetic analysis of pathogenic organisms is a useful tool for linking human cases together and/or to potential environmental sources. The resulting data can also provide information on evolutionary patterns within a targeted species and phenotypic traits. However, the instruments often used to generate genotyping data, such as single nucleotide polymorphisms (SNPs, can be expensive and sometimes require advanced technologies to implement. This places many genotyping tools out of reach for laboratories that do not specialize in genetic studies and/or lack the requisite financial and technological resources. To address this issue, we developed a low cost and low tech genotyping system, termed agarose-MAMA, which combines traditional PCR and agarose gel electrophoresis to target phylogenetically informative SNPs.To demonstrate the utility of this approach for generating genotype data in a resource-constrained area (Madagascar, we designed an agarose-MAMA system targeting previously characterized SNPs within Yersinia pestis, the causative agent of plague. We then used this system to genetically type pathogenic strains of Y. pestis in a Malagasy laboratory not specialized in genetic studies, the Institut Pasteur de Madagascar (IPM. We conducted rigorous assay performance validations to assess potential variation introduced by differing research facilities, reagents, and personnel and found no difference in SNP genotyping results. These agarose-MAMA PCR assays are currently employed as an investigative tool at IPM, providing Malagasy researchers a means to improve the value of their plague epidemiological investigations by linking outbreaks to potential sources through genetic characterization of isolates and to improve understanding of disease ecology that may contribute to a long-term control effort.The success of our study demonstrates that the SNP-based genotyping capacity of laboratories in developing countries can be expanded with manageable

Low cost, low tech SNP genotyping tools for resource-limited areas: Plague in Madagascar as a model.

Science.gov (United States)

Mitchell, Cedar L; Andrianaivoarimanana, Voahangy; Colman, Rebecca E; Busch, Joseph; Hornstra-O'Neill, Heidie; Keim, Paul S; Wagner, David M; Rajerison, Minoarisoa; Birdsell, Dawn N

2017-12-01

Genetic analysis of pathogenic organisms is a useful tool for linking human cases together and/or to potential environmental sources. The resulting data can also provide information on evolutionary patterns within a targeted species and phenotypic traits. However, the instruments often used to generate genotyping data, such as single nucleotide polymorphisms (SNPs), can be expensive and sometimes require advanced technologies to implement. This places many genotyping tools out of reach for laboratories that do not specialize in genetic studies and/or lack the requisite financial and technological resources. To address this issue, we developed a low cost and low tech genotyping system, termed agarose-MAMA, which combines traditional PCR and agarose gel electrophoresis to target phylogenetically informative SNPs. To demonstrate the utility of this approach for generating genotype data in a resource-constrained area (Madagascar), we designed an agarose-MAMA system targeting previously characterized SNPs within Yersinia pestis, the causative agent of plague. We then used this system to genetically type pathogenic strains of Y. pestis in a Malagasy laboratory not specialized in genetic studies, the Institut Pasteur de Madagascar (IPM). We conducted rigorous assay performance validations to assess potential variation introduced by differing research facilities, reagents, and personnel and found no difference in SNP genotyping results. These agarose-MAMA PCR assays are currently employed as an investigative tool at IPM, providing Malagasy researchers a means to improve the value of their plague epidemiological investigations by linking outbreaks to potential sources through genetic characterization of isolates and to improve understanding of disease ecology that may contribute to a long-term control effort. The success of our study demonstrates that the SNP-based genotyping capacity of laboratories in developing countries can be expanded with manageable financial cost for

Accelerated hatching of southern leopard frog (Rana sphenocephala) eggs in response to the presence of a crayfish Procambarus nigrocinctus predator

Science.gov (United States)

Daniel Saenz; James B. Johnson; Cory K. Adams; Gage H. Dayton

2003-01-01

Phenotypic plasticity, such as morphological and behavioral changes in response to predators, is common in larval anurans. Less is known about inducible defenses in the embryonic stages of development. We investigated the predation risk imposed by crayfish (Procambarus nigrocinctus) on southern leopard frog (Rana sphenocephala)...

Three days in October of 1630: detailed examination of mortality during an early modern plague epidemic in Venice.

Science.gov (United States)

Ell, S R

1989-01-01

The epidemiology of medieval and early modern European plague remains highly controversial. It now seems likely that the epidemiology was not uniform throughout either the geographic or temporal boundaries of the plague in Western Europe. The Venetian plague of 1630 was extensively documented; day-by-day records were kept, and each mortality in the city was recorded in a set format. The days 23-25 October 1630, representing a period when mortality was beginning to increase sharply, are examined. In all, 1,163 deaths were recorded. They show a large preponderance of women; a mean age of 28, but a majority of cases clumped between ages 0 and 25 years; and an unequal sex ratio among children. Further, there was an identifiable smallpox epidemic raging simultaneously with plague, and more than one-quarter of all the deaths in this period of high mortality were clearly due to nonplague causes. Deaths due to wounds and associated with violence were prominent in one parish, which suggests that in times of plague the breakdown in the normal machinery of government, in everyday patterns of life, and possibly of mental well being resulted in an even more exaggerated death toll. These factors--violence, accidents, and other epidemics--have never been so definitively tied to a European plague epidemic. In addition, there are hints that plague has a marked proclivity to kill pregnant women--their deaths far outnumber those anticipated--and that plague was very localized at a given moment within Venice itself, even during times of peak mortality.

[Preventive measures against plague and the control of Chinese coolies in colonial Korea].

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Kim, Youngsoo

2014-12-01

This paper aims to examine the preventive measures taken against the plague in colonial Korea, particularly as applied to the control of Chinese coolies in 1911, soon after the annexation. The Government General of Korea began preventive measures with a train quarantine in Shin'uiju and Incheon in response to the spread of the plague to the Southern Manchuria. Shin' uiju had become urbanized due the development of the transportation network, and the seaport of Incheon was the major hub for traffic with China. Examining the transportation routes for the entry and exit of Chinese to and from Korea makes clear the reason why the Korea Government General initiated preventive measures in mid-January, 1911. The Government General of Korea tried to block the entry of Chinese through the land border crossing with China and through ports of entry, primarily Incheon. During the implementation of the preventive measures, quarantine facilities were built, including a quarantine station and isolation facility in Incheon. It was also needed to investigate the population and residential locations of Chinese in Korea to prevent the spread of plague. A certificate of residence was issued to all Chinese in Korea, which they needed to carry when they travelled. The preventive measures against plague which broke out in Manchuria were removed gradually. However, there was no specific measures against Chinese coolies, those who had migrated from China to work in the spring in Korea. Still the Government General of Korea had doubt about an infection of the respiratory system. As a result, the labor market in colonial Korea underwent changes in this period. The Government General recruited Korean laborers, instead of Chinese coolies whose employment had been planned. This move explains the Government General's strong preventive measures against plague and uncertainty in the route of plague infection, which influenced subsequent regulations on the prohibition of Chinese coolies working on

Seroprevalence of hantavirus and Yersinia pestis antibodies in professionals from the Plague Control Program

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Erika de Cassia Vieira da Costa

2013-07-01

Full Text Available Introduction Professionals who handle rodents in the field and in the laboratory are at risk of infection by the microorganisms harbored by these animals. Methods Serum samples from professionals involved in rodent and Yersinia pestis handling in field or laboratory work were analyzed to determine hantavirus and plague seroprevalence and to establish a relationship between these activities and reports of illnesses. Results Two individuals had antibodies against hantavirus, and two harbored antibodies against the plague; none of the individuals had experienced an illness related to their duties. Conclusions These results confirm the risks of hantavirus- and plague-related field and laboratory activities and the importance of protective measures for such work.

A rapid field test for sylvatic plague exposure in wild animals

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Abbott, Rachel C.; Hudak, Robert; Mondesire, Roy; Baeten, Laurie A.; Russell, Robin E.; Rocke, Tonie E.

2014-01-01

Plague surveillance is routinely conducted to predict future epizootics in wildlife and exposure risk for humans. The most common surveillance method for sylvatic plague is detection of antibodies to Yersinia pestis F1 capsular antigen in sentinel animals, such as coyotes (Canis latrans). Current serologic tests for Y. pestis, hemagglutination (HA) test and enzyme-linked immunosorbent assay (ELISA), are expensive and labor intensive. To address this need, we developed a complete lateral flow device for the detection of specific antibodies to Y. pestis F1 and V antigens. Our test detected anti-F1 and anti-V antibodies in serum and Nobuto filter paper samples from coyotes, and in serum samples from prairie dogs (Cynomys ludovicianus), lynx (Lynx canadensis), and black-footed ferrets (Mustela nigripes). Comparison of cassette results for anti-F1 and anti-V antibodies with results of ELISA or HA tests showed correlations ranging from 0.68 to 0.98. This device provides an affordable, user-friendly tool that may be useful in plague surveillance programs and as a research tool.

A Replication-Defective Human Type 5 Adenovirus-Based Trivalent Vaccine Confers Complete Protection against Plague in Mice and Nonhuman Primates.

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Sha, Jian; Kirtley, Michelle L; Klages, Curtis; Erova, Tatiana E; Telepnev, Maxim; Ponnusamy, Duraisamy; Fitts, Eric C; Baze, Wallace B; Sivasubramani, Satheesh K; Lawrence, William S; Patrikeev, Igor; Peel, Jennifer E; Andersson, Jourdan A; Kozlova, Elena V; Tiner, Bethany L; Peterson, Johnny W; McWilliams, David; Patel, Snehal; Rothe, Eric; Motin, Vladimir L; Chopra, Ashok K

2016-07-01

Currently, no plague vaccine exists in the United States for human use. The capsular antigen (Caf1 or F1) and two type 3 secretion system (T3SS) components, the low-calcium-response V antigen (LcrV) and the needle protein YscF, represent protective antigens of Yersinia pestis We used a replication-defective human type 5 adenovirus (Ad5) vector and constructed recombinant monovalent and trivalent vaccines (rAd5-LcrV and rAd5-YFV) that expressed either the codon-optimized lcrV or the fusion gene designated YFV (consisting of ycsF, caf1, and lcrV). Immunization of mice with the trivalent rAd5-YFV vaccine by either the intramuscular (i.m.) or the intranasal (i.n.) route provided protection superior to that with the monovalent rAd5-LcrV vaccine against bubonic and pneumonic plague when animals were challenged with Y. pestis CO92. Preexisting adenoviral immunity did not diminish the protective response, and the protection was always higher when mice were administered one i.n. dose of the trivalent vaccine (priming) followed by a single i.m. booster dose of the purified YFV antigen. Immunization of cynomolgus macaques with the trivalent rAd5-YFV vaccine by the prime-boost strategy provided 100% protection against a stringent aerosol challenge dose of CO92 to animals that had preexisting adenoviral immunity. The vaccinated and challenged macaques had no signs of disease, and the invading pathogen rapidly cleared with no histopathological lesions. This is the first report showing the efficacy of an adenovirus-vectored trivalent vaccine against pneumonic plague in mouse and nonhuman primate (NHP) models. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Predation of the alien American mink Mustela vison on native crayfish populations in middle-sized streams in central and western Bohemia

Czech Academy of Sciences Publication Activity Database

Fischer, D.; Pavluvčík, P.; Sedláček, František; Šálek, Martin

2009-01-01

Roč. 58, č. 1 (2009), s. 45-56 ISSN 0139-7893 Institutional research plan: CEZ:AV0Z60870520 Keywords : mink diet * stone crayfish * prey selectivity * density-dependent predation * Czech Republic Subject RIV: EG - Zoology Impact factor: 0.357, year: 2009

An overview of plague in the United States and a report of investigations of two human cases in Kern county, California, 1995.

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Madon, M B; Hitchcock, J C; Davis, R M; Myers, C M; Smith, C R; Fritz, C L; Emery, K W; O'Rullian, W

1997-06-01

Plague was confirmed in the United States from nine western states during 1995. Evidence of Yersinia pestis infection was identified in 28 species of wild or domestic mammals. Thirteen of the plague positive species were wild rodents; 15 were predators/carnivores. Yersinia pestis was isolated from eight species of fleas. Seven confirmed cases of human plague were reported in 1995 (New Mexico 3; California 2; Arizona and Oregon 1 each). Five of the seven cases were bubonic; one was septicemic and one a fatal pneumonic case. Months of onset ranged from March through August. In California, during 1995, plague was recorded from 15 of the 58 counties. Over 1,500 animals were tested, of which 208 were plague positive. These included 144 rodents and 64 predators/carnivores. Two confirmed human cases (one bubonic and one fatal pneumonic) occurred, both in Kern County. Case No. 1 was reported from the town of Tehachapi. The patient, a 23 year-old male resident, died following a diagnosis of plague pneumonia. The patient's source of plague infection could not be determined precisely. Field investigations revealed an extensive plague epizootic surrounding Tehachapi, an area of approximately 500-600 square miles (800-970 square kilometers). Case No. 2 was a 57 year-old female diagnosed with bubonic plague; she was placed on an antibiotic regimen and subsequently recovered. The patient lives approximately 20 miles (32 km) north of Tehachapi. Field investigations revealed evidence of a plague epizootic in the vicinity of the victim's residence and adjacent areas. Overall results of the joint field investigations throughout the entire Kern county area revealed a high rate of plague positive animals. Of the numerous samples submitted, 48 non-human samples were plague positive.

Small-Scale Die-Offs in Woodrats Support Long-Term Maintenance of Plague in the U.S. Southwest.

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Kosoy, Michael; Reynolds, Pamela; Bai, Ying; Sheff, Kelly; Enscore, Russell E; Montenieri, John; Ettestad, Paul; Gage, Kenneth

2017-09-01

Our longitudinal study of plague dynamics was conducted in north-central New Mexico to identify which species in the community were infected with plague, to determine the spatial and temporal patterns of the dynamics of plague epizootics, and to describe the dynamics of Yersinia pestis infection within individual hosts. A total of 3156 fleas collected from 535 small mammals of 8 species were tested for Y. pestis DNA. Nine fleas collected from six southern plains woodrats (Neotoma micropus) and from one rock squirrel (Otospermophilus variegatus) were positive for the pla gene of Y. pestis. None of 127 fleas collected from 17 woodrat nests was positive. Hemagglutinating antibodies to the Y. pestis-specific F1 antigen were detected in 11 rodents of 6 species. All parts of the investigated area were subjected to local disappearance of woodrats. Despite the active die-offs, some woodrats always were present within the relatively limited endemic territory and apparently were never exposed to plague. Our observations suggest that small-scale die-offs in woodrats can support maintenance of plague in the active U.S. Southwestern focus.

[Mechanisms of power in disease: the case of the novel "The Plague" by Albert Camus].

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Hernández-Mansilla, José Miguel

2009-01-01

This paper explores the elements of power that can be found in an epidemic like the plague. To undertake this task we first studied, the form of containment of the plague from a historical perspective and then, compare them with those described by Camus in his novel The Plague. We also studied the experience of sin among humans in an effort to determine divine power. This last point explores the fear of being touched during an epidemic and how this is overcome by the innate feeling of love among men. Finally in the novel, this is illustrated by the love of Orpheus for Eurydice.

Quinto Tiberio Angelerio and New Measures for Controlling Plague in 16th-Century Alghero, Sardinia

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Benedictow, Ole Jørgen; Fornaciari, Gino; Giuffra, Valentina

2013-01-01

Plague, a zoonotic disease caused by the bacterium Yersinia pestis, has been responsible for at least 3 pandemics. During 1582–1583, a plague outbreak devastated the seaport of Alghero in Sardinia. By analyzing contemporary medical texts and local documentation, we uncovered the pivotal role played by the Protomedicus of Alghero, Quinto Tiberio Angelerio (1532–1617), in controlling the epidemic. Angelerio imposed rules and antiepidemic measures new to the 16th-century sanitary system of Sardinia. Those measures undoubtedly spared the surrounding districts from the spread of the contagion. Angelerio seems to have been an extremely successful public health officer in the history of plague epidemics in Sardinia. PMID:23968598

SIFamide peptides in clawed lobsters and freshwater crayfish (Crustacea, Decapoda, Astacidea): a combined molecular, mass spectrometric and electrophysiological investigation.

Science.gov (United States)

Dickinson, Patsy S; Stemmler, Elizabeth A; Cashman, Christopher R; Brennan, Henry R; Dennison, Bobbi; Huber, Kristen E; Peguero, Braulio; Rabacal, Whitney; Goiney, Christopher C; Smith, Christine M; Towle, David W; Christie, Andrew E

2008-04-01

Recently, we identified the peptide VYRKPPFNGSIFamide (Val(1)-SIFamide) in the stomatogastric nervous system (STNS) of the American lobster Homarus americanus using matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry (MALDI-FTMS). Given that H. americanus is the only species thus far shown to possess this peptide, and that a second SIFamide isoform, Gly(1)-SIFamide, is broadly conserved in other decapods, including another astacidean, the crayfish Procambarus clarkii, we became interested both in confirming our identification of Val(1)-SIFamide via molecular methods and in determining the extent to which this isoform is conserved within other members of the infraorder Astacidea. Here, we present the identification and characterization of an H. americanus prepro-SIFamide cDNA that encodes the Val(1) isoform. Moreover, we demonstrate via MALDI-FTMS the presence of Val(1)-SIFamide in a second Homarus species, Homarus gammarus. In contrast, only the Gly(1) isoform was detected in the other astacideans investigated, including the lobster Nephrops norvegicus, a member of the same family as Homarus, and the crayfish Cherax quadricarinatus, P. clarkii and Pacifastacus leniusculus, which represent members of each of the extant families of freshwater astacideans. These results suggest that Val(1)-SIFamide may be a genus (Homarus)-specific isoform. Interestingly, both Val(1)- and Gly(1)-SIFamide possess an internal dibasic site, Arg(3)-Lys(4), raising the possibility of the ubiquitously conserved isoform PPFNGSIFamide. However, this octapeptide was not detected via MALDI-FTMS in any of the investigated species, and when applied to the isolated STNS of H. americanus possessed little bioactivity relative to the full-length Val(1) isoform. Thus, it appears that the dodeca-variants Val(1)- and Gly(1)-SIFamide are the sole bioactive isoforms of this peptide family in clawed lobsters and freshwater crayfish.

Improvement of disease prediction and modeling through the use of meteorological ensembles: human plague in Uganda.

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Sean M Moore

Full Text Available Climate and weather influence the occurrence, distribution, and incidence of infectious diseases, particularly those caused by vector-borne or zoonotic pathogens. Thus, models based on meteorological data have helped predict when and where human cases are most likely to occur. Such knowledge aids in targeting limited prevention and control resources and may ultimately reduce the burden of diseases. Paradoxically, localities where such models could yield the greatest benefits, such as tropical regions where morbidity and mortality caused by vector-borne diseases is greatest, often lack high-quality in situ local meteorological data. Satellite- and model-based gridded climate datasets can be used to approximate local meteorological conditions in data-sparse regions, however their accuracy varies. Here we investigate how the selection of a particular dataset can influence the outcomes of disease forecasting models. Our model system focuses on plague (Yersinia pestis infection in the West Nile region of Uganda. The majority of recent human cases have been reported from East Africa and Madagascar, where meteorological observations are sparse and topography yields complex weather patterns. Using an ensemble of meteorological datasets and model-averaging techniques we find that the number of suspected cases in the West Nile region was negatively associated with dry season rainfall (December-February and positively with rainfall prior to the plague season. We demonstrate that ensembles of available meteorological datasets can be used to quantify climatic uncertainty and minimize its impacts on infectious disease models. These methods are particularly valuable in regions with sparse observational networks and high morbidity and mortality from vector-borne diseases.

Improvement of Disease Prediction and Modeling through the Use of Meteorological Ensembles: Human Plague in Uganda

Science.gov (United States)

Moore, Sean M.; Monaghan, Andrew; Griffith, Kevin S.; Apangu, Titus; Mead, Paul S.; Eisen, Rebecca J.

2012-01-01

Climate and weather influence the occurrence, distribution, and incidence of infectious diseases, particularly those caused by vector-borne or zoonotic pathogens. Thus, models based on meteorological data have helped predict when and where human cases are most likely to occur. Such knowledge aids in targeting limited prevention and control resources and may ultimately reduce the burden of diseases. Paradoxically, localities where such models could yield the greatest benefits, such as tropical regions where morbidity and mortality caused by vector-borne diseases is greatest, often lack high-quality in situ local meteorological data. Satellite- and model-based gridded climate datasets can be used to approximate local meteorological conditions in data-sparse regions, however their accuracy varies. Here we investigate how the selection of a particular dataset can influence the outcomes of disease forecasting models. Our model system focuses on plague (Yersinia pestis infection) in the West Nile region of Uganda. The majority of recent human cases have been reported from East Africa and Madagascar, where meteorological observations are sparse and topography yields complex weather patterns. Using an ensemble of meteorological datasets and model-averaging techniques we find that the number of suspected cases in the West Nile region was negatively associated with dry season rainfall (December-February) and positively with rainfall prior to the plague season. We demonstrate that ensembles of available meteorological datasets can be used to quantify climatic uncertainty and minimize its impacts on infectious disease models. These methods are particularly valuable in regions with sparse observational networks and high morbidity and mortality from vector-borne diseases. PMID:23024750

Yersinia pestis subverts the dermal neutrophil response in a mouse model of bubonic plague.

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Shannon, Jeffrey G; Hasenkrug, Aaron M; Dorward, David W; Nair, Vinod; Carmody, Aaron B; Hinnebusch, B Joseph

2013-08-27

The majority of human Yersinia pestis infections result from introduction of bacteria into the skin by the bite of an infected flea. Once in the dermis, Y. pestis can evade the host's innate immune response and subsequently disseminate to the draining lymph node (dLN). There, the pathogen replicates to large numbers, causing the pathognomonic bubo of bubonic plague. In this study, several cytometric and microscopic techniques were used to characterize the early host response to intradermal (i.d.) Y. pestis infection. Mice were infected i.d. with fully virulent or attenuated strains of dsRed-expressing Y. pestis, and tissues were analyzed by flow cytometry. By 4 h postinfection, there were large numbers of neutrophils in the infected dermis and the majority of cell-associated bacteria were associated with neutrophils. We observed a significant effect of the virulence plasmid (pCD1) on bacterial survival and neutrophil activation in the dermis. Intravital microscopy of i.d. Y. pestis infection revealed dynamic interactions between recruited neutrophils and bacteria. In contrast, very few bacteria interacted with dendritic cells (DCs), indicating that this cell type may not play a major role early in Y. pestis infection. Experiments using neutrophil depletion and a CCR7 knockout mouse suggest that dissemination of Y. pestis from the dermis to the dLN is not dependent on neutrophils or DCs. Taken together, the results of this study show a very rapid, robust neutrophil response to Y. pestis in the dermis and that the virulence plasmid pCD1 is important for the evasion of this response. Yersinia pestis remains a public health concern today because of sporadic plague outbreaks that occur throughout the world and the potential for its illegitimate use as a bioterrorism weapon. Since bubonic plague pathogenesis is initiated by the introduction of Y. pestis into the skin, we sought to characterize the response of the host's innate immune cells to bacteria early after

Melanization and Pathogenicity in the Insect, Tenebrio molitor, and the Crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3

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Noonin, Chadanat; Jiravanichpaisal, Pikul; Söderhäll, Irene; Merino, Susana; Tomás, Juan M.; Söderhäll, Kenneth

2010-01-01

Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS), bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish) and Tenebrio molitor larvae (mealworm). The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core) is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT) containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the proPO system

Melanization and pathogenicity in the insect, Tenebrio molitor, and the crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3.

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Chadanat Noonin

Full Text Available Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS, bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish and Tenebrio molitor larvae (mealworm. The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the

Residue analysis of sixty pesticides in red swamp crayfish using QuEChERS with high-performance liquid chromatography-tandem mass spectrometry

Science.gov (United States)

In this study, a multi-residue analytical method using QuEChERS extraction and dispersive solid-phase extraction (d-SPE) cleanup followed by high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) was developed for rapid determination of 60 pesticide residues in whole crayfish a...

New alternatives on the control of plagues in the handling of the residuals in agricultural products

International Nuclear Information System (INIS)

Mendez Buenaventura, L.

1995-01-01

A recount of the historical evolution of the agriculture is made in the country and the use of agricultural inputs with tendency to the mono cultivations that drove to a biological imbalance and the escalation of the plagues in the main cultivations, that which forced to the integrated handling of plagues. The strategies are described using in the control integrated as they are: the use of the adverse environmental factors to the plagues, the use of the natural enemies, the cultural practices, the use of traps, the employment of resistant varieties and measures of legal type

Appropriate Usage Level of Shrimp Waste Meal as Chitin Source for Feeding Young Crayfish (Astacus leptodactylus Esch. 1823

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Seval Bahadır Koca*, Nalan Ozgur Yigit, Arife Dulluc, Gonca Erol1, Nihal Cılbız1 and Ramazan Kucukkara1

2011-06-01

Full Text Available This study was conducted to determine effects of shrimp waste meal as natural chitin source at different rates (0 (control, 10, 20, 30 and 40% on growth, feed conversion ratio (FCR, survival of young crayfish (1.61±0.04 g and 3.74±0.03 cm for 60 days. Fifteen glass aquariums (70x30x40 cm were used in the experiment and 20 individuals were stocked per aquarium (95/m2. The highest of final weight and weight gain were obtained in feed with 10% shrimp waste meal group (3.29±0.23 and 1.66±0.23 g, while the lowest of final weight and weight gain was obtained in fed with 40% shrimp waste meal group (2.75±0.35 and 1.18±0.37 g, respectively. However, non-significant differences were found between final weight, weight gain, specific growth rate, final total length, feed conversion ratio, survival percentage among groups at the end of experimental period. It was concluded that shrimp waste meal as natural chitin source can be used in young crayfish diets up to 40% without adverse effect influence on growth.

Investigation of and Response to 2 Plague Cases, Yosemite National Park, California, USA, 2015.

Science.gov (United States)

Danforth, Mary; Novak, Mark; Petersen, Jeannine; Mead, Paul; Kingry, Luke; Weinburke, Matthew; Buttke, Danielle; Hacker, Gregory; Tucker, James; Niemela, Michael; Jackson, Bryan; Padgett, Kerry; Liebman, Kelly; Vugia, Duc; Kramer, Vicki

2016-12-01

In August 2015, plague was diagnosed for 2 persons who had visited Yosemite National Park in California, USA. One case was septicemic and the other bubonic. Subsequent environmental investigation identified probable locations of exposure for each patient and evidence of epizootic plague in other areas of the park. Transmission of Yersinia pestis was detected by testing rodent serum, fleas, and rodent carcasses. The environmental investigation and whole-genome multilocus sequence typing of Y. pestis isolates from the patients and environmental samples indicated that the patients had been exposed in different locations and that at least 2 distinct strains of Y. pestis were circulating among vector-host populations in the area. Public education efforts and insecticide applications in select areas to control rodent fleas probably reduced the risk for plague transmission to park visitors and staff.

Mitotic karyotype of the tropical freshwater crayfish Procambarus (Austrocambarus llamasi (Decapoda: Cambaridae

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Jeane R Indy

2010-06-01

Full Text Available In Mexico, the biology of Procambarus has been more studied than the biology of other Cambarids because of its diversity and potential use in aquaculture. We determined the karyotype of the Mexican tropical freshwater crayfish Procambarus (Austrocambarus llamasi from 189 metaphase spreads from gill tissues of 17 adults. They had 98-120 chromosomes (mode 2n=120 chromosomes. There are 60 pairs of monoarm, telocentric chromosomes. Sex chromosomes were not detected and we propose that the P. llamasi karyotype can be used to distinguish this species from other Mexican crayfish. Additionally, we suggest using karyological data in aquaculture and conservation biology. Rev. Biol. Trop. 58 (2: 655-662. Epub 2010 June 02.El género Procambarus ha recibido mayor atención en los estudios de los principios fundamentales de su biología debido a su diversidad en el territorio mexicano y potencial uso en acuicultura. El cariotipo típico del acocil tropical mexicano Procambarus (Austrocambarus llamasi, se estudió mediante 189 dispersiones cromosómicas en metafase del tejido branquial de 17 adultos tratados con la técnica citológica de inmersión. Encontramos un amplio número de cromosomas, que variaron entre 98-120 elementos cromosómicos, con número modal diploide de 2n=120 elementos cromosómicos. El cariotipo del acocil tropical esta constituido por 60 pares de cromosomas monorrámeos, todos los centrómero están en la región telocéntrica de los cromosomas. En las metafases mitóticas de hembras y machos no fueron identificados cromosomas sexuales. Sugerimos considerar la estructura cromosómica del cariotipo como una herramienta citotaxonómica así como el empleo de datos cariológicos para propósitos de acuicultura y conservación del acocil tropical.

Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America.

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Eads, David A; Biggins, Dean E

2015-08-01

Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research. © 2015 Society for Conservation Biology.

Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America

Science.gov (United States)

Eads, David A.; Biggins, Dean E.

2015-01-01

Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research.

Red swamp crayfish: biology, ecology and invasion - an overview

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Tainã Gonçalves Loureiro

Full Text Available ABSTRACTAlien species have been transported and traded by humans for many centuries. However, with the era of globalization, biological invasions have reached notable magnitudes. Currently, introduction of alien species is one of the major threats to biodiversity and ecosystem functioning. The North American crayfish Procambarus clarkii is one of the most widely introduced freshwater species in the world, especially due to its high economic importance. It is responsible for great modifications in invaded environments causing irreparable ecological and economic damages. Its impressive ability to successfully colonize a wide range of environments is a consequence of its behavioural and biological characteristics that can adapt to features of the invaded location, conferring to this species a notable ecological plasticity. This review summarizes the available information regarding P. clarkii's biology and invasive dynamics around the world in order to contribute to the understanding of the threats posed by its establishment, as well as to support management and impact mitigation efforts.

Lunar-Rhythmic Molting in Laboratory Populations of the Noble Crayfish Astacus astacus (Crustacea, Astacidea): An Experimental Analysis

Science.gov (United States)

Franke, Robert; Hoerstgen-Schwark, Gabriele

2013-01-01

Juvenile noble crayfish, Astacusastacus (Crustacea, Astacidea) in the second year of age were kept in the laboratory for a twelve-month period under continuing “summer conditions” (LD 16:8, 19°C). Molting processes in this population could be synchronized by artificial moonlight cycles. Peaks of exuviations occurred at “new moons”. Males showed a slightly higher degree of synchronization than females. A phase-shift of the artificial lunar cycle in relation to the natural cycle resulted in a corresponding shift of the molting cycle. This clearly demonstrates that changes in the nocturnal light regime provide the primary external information for the lunar-monthly molting rhythm. There is a first indication that lunar photic stimuli do not act directly but as a zeitgeber which entrains an endogenous molting rhythm to the lunar cycle. Moreover, the results of the long-term experiments suggest that the hibernal resting period of A . astacus in the field (no molts between October and April) may also involve some endogenous programming. Continuing artificial summer conditions can delay but not completely suppress this resting period. The adaptive significance of the phenomena and how the findings may be applied to improve the management of crowded crayfish stocks are discussed. PMID:23840899

Two Distinct Yersinia pestis Populations Causing Plague among Humans in the West Nile Region of Uganda.

Science.gov (United States)

Respicio-Kingry, Laurel B; Yockey, Brook M; Acayo, Sarah; Kaggwa, John; Apangu, Titus; Kugeler, Kiersten J; Eisen, Rebecca J; Griffith, Kevin S; Mead, Paul S; Schriefer, Martin E; Petersen, Jeannine M

2016-02-01

Plague is a life-threatening disease caused by the bacterium, Yersinia pestis. Since the 1990s, Africa has accounted for the majority of reported human cases. In Uganda, plague cases occur in the West Nile region, near the border with Democratic Republic of Congo. Despite the ongoing risk of contracting plague in this region, little is known about Y. pestis genotypes causing human disease. During January 2004-December 2012, 1,092 suspect human plague cases were recorded in the West Nile region of Uganda. Sixty-one cases were culture-confirmed. Recovered Y. pestis isolates were analyzed using three typing methods, single nucleotide polymorphisms (SNPs), pulsed field gel electrophoresis (PFGE), and multiple variable number of tandem repeat analysis (MLVA) and subpopulations analyzed in the context of associated geographic, temporal, and clinical data for source patients. All three methods separated the 61 isolates into two distinct 1.ANT lineages, which persisted throughout the 9 year period and were associated with differences in elevation and geographic distribution. We demonstrate that human cases of plague in the West Nile region of Uganda are caused by two distinct 1.ANT genetic subpopulations. Notably, all three typing methods used, SNPs, PFGE, and MLVA, identified the two genetic subpopulations, despite recognizing different mutation types in the Y. pestis genome. The geographic and elevation differences between the two subpopulations is suggestive of their maintenance in highly localized enzootic cycles, potentially with differing vector-host community composition. This improved understanding of Y. pestis subpopulations in the West Nile region will be useful for identifying ecologic and environmental factors associated with elevated plague risk.

Observations on the endemicity of plague in Karatu and Ngorongoro, northern Tanzania.

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Kilonzo, B S; Mbise, T J; Mwalimu, D C; Kindamba, L

2006-01-01

Commensal and field rodents and wild small carnivores were live-trapped in five villages of Karatu district and one settlement in the Ngorongoro Conservation Area in Ngorongoro district in Tanzania. Blood samples were taken and serologically tested for plague, using the Blocking ELISA technique. Some domestic dogs and cats in the Karatu villages were aseptically bled and similarly tested for plague. Fleas were collected from the examined animals and from randomly selected residential houses. A total of 241 rodents, 1 Crocidura spp, 43 dogs, 12 cats and 4 slender mongooses were involved in the survey. Of the rodents, 14.5% were infested with fleas, which comprised of Xenopsylla brasiliensis (45.8%) and Dinopsyllus lypusus (54.2%), with an overall population density of 0.2 fleas/animal. Thirty one (72.1%) of the dogs were infested with fleas, all of which were Ctenocephalides spp. Thirty five (63.3%) houses were infested with fleas whose population was composed of Ctenocephalides spp, Pulex irritans, Tunga penetrans and Echinophaga gallinacea. Infected rodents were found in all the villages while the infected dog was found at Rhotia-Kati. Nineteen (11%) of the rodents and one (2%) dog harboured specific plague antibodies. It was broadly concluded that sylvatic plague was endemic in Karatu district and Ngorongoro Conservation Area and that outbreaks of the disease can occur in the area any time if and when relevant conditions become favourable. Prompt application of appropriate preventive and control measures and survey for substantiating the status in the Lake Manyara National Park, which is adjacent to some of the infected villages, are recommended.

Do environmental changes or juvenile competition act as mechanisms of species displacement in crayfishes?

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Westhoff, Jacob T.; DiStefano, R.J.; Magoulick, D.D.

2012-01-01

The Big Creek Crayfish, Orconectes peruncus, is native to the St. Francis River drainage in Missouri, USA and is often absent where the introduced Woodland Crayfish, Orconectes hylas, has established. We performed a field experiment to determine whether effects of current abiotic conditions and interspecific competition with O. hylas were responsible for displacement of O. peruncus from parts of their former range. We examined growth and survival of juvenile male O. peruncus exposed to juvenile male O. hylas in enclosures at two sites in the former range of O. peruncus. Enclosures contained 8 (low density) or 16 individuals (high density) and had O. peruncus only (control) or both species (interspecific treatment). Juvenile O. peruncus were able to survive and grow in portions of their former range, implicating biotic versus abiotic factors in the displacement of O. peruncus. Survival rates of O. peruncus did not differ among treatments at either site. Orconectes peruncus showed significant growth in all treatments and interspecific effects were not greater than intraspecific effects on O. peruncus growth rates. High-density treatments showed significantly reduced O. peruncus growth rates compared to low-density treatments, except in Carver Creek interspecific treatments. When considered in the context of previous studies examining the effects of O. hylas on O. peruncus, results suggest that neither direct competition between juvenile males of the two species or abiotic change are responsible for the decreased range of O. peruncus. Additional research is required to determine the mechanism(s) driving the displacement of O. peruncus. ?? 2011 Springer Science+Business Media B.V.

Plague cycles in two rodent species from China: Dry years might provide context for epizootics in wet years

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Eads, David A.; Biggins, Dean E.; Xu, Lei; Liu, Qiyong

2016-01-01

Plague, a rodent-associated, flea-borne zoonosis, is one of the most notorious diseases in history. Rates of plague transmission can increase when fleas are abundant. Fleas commonly desiccate and die when reared under dry conditions in laboratories, suggesting fleas will be suppressed during droughts in the wild, thus reducing the rate at which plague spreads among hosts. In contrast, fleas might increase in abundance when precipitation is plentiful, producing epizootic outbreaks during wet years. We tested these hypotheses using a 27-yr data set from two rodents in Inner Mongolia, China: Mongolian gerbils (Meriones unguiculatus) and Daurian ground squirrels (Spermophilus dauricus). For both species of rodents, fleas were most abundant during years preceded by dry growing seasons. For gerbils, the prevalence of plague increased during wet years preceded by dry growing seasons. If precipitation is scarce during the primary growing season, succulent plants decline in abundance and, consequently, herbivorous rodents can suffer declines in body condition. Fleas produce more offspring and better survive when parasitizing food-limited hosts, because starving animals tend to exhibit inefficient behavioral and immunological defenses against fleas. Further, rodent burrows might buffer fleas from xeric conditions aboveground during dry years. After a dry year, fleas might be abundant due to the preceding drought, and if precipitation and succulent plants become more plentiful, rodents could increase in density, thereby creating connectivity that facilitates the spread of plague. Moreover, in wet years, mild temperatures might increase the efficiency at which fleas transmit the plague bacterium, while also helping fleas to survive as they quest among hosts. In this way, dry years could provide context for epizootics of plague in wet years.

Demographic and spatio-temporal variation in human plague at a persistent focus in Tanzania

DEFF Research Database (Denmark)

Davis, S; Makundi, R H; Machang'u, R S

2006-01-01

Human plague in the Western Usambara Mountains in Tanzania has been a public health problem since the first outbreak in 1980. The wildlife reservoir is unknown and eradication measures that have proved effective elsewhere in Tanzania appear to fail in this region. We use census data from 2002...... and hospital records kept since 1986 to describe the temporal, spatial and demographic variation in human plague. A seasonal peak in cases occurs from December to February with the numbers of cases during this peak varying between 0 and 1150. Variation in incidence, calculated for each village as the mean...... number of cases per thousand inhabitants per year, indicates that human plague is concentrated around a group of three neighbouring, relatively isolated, high-altitude villages; Nywelo, Madala and Gologolo. However, there was no evidence that these villages were acting as a source of infection...

Investigation of and Response to 2 Plague Cases, Yosemite National Park, California, USA, 2015

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Danforth, Mary; Novak, Mark; Petersen, Jeannine; Mead, Paul; Kingry, Luke; Weinburke, Matthew; Buttke, Danielle; Hacker, Gregory; Tucker, James; Niemela, Michael; Jackson, Bryan; Padgett, Kerry; Liebman, Kelly; Vugia, Duc

2016-01-01

In August 2015, plague was diagnosed for 2 persons who had visited Yosemite National Park in California, USA. One case was septicemic and the other bubonic. Subsequent environmental investigation identified probable locations of exposure for each patient and evidence of epizootic plague in other areas of the park. Transmission of Yersinia pestis was detected by testing rodent serum, fleas, and rodent carcasses. The environmental investigation and whole-genome multilocus sequence typing of Y. pestis isolates from the patients and environmental samples indicated that the patients had been exposed in different locations and that at least 2 distinct strains of Y. pestis were circulating among vector–host populations in the area. Public education efforts and insecticide applications in select areas to control rodent fleas probably reduced the risk for plague transmission to park visitors and staff. PMID:27870634

Factors influencing uptake of sylvatic plague vaccine baits by prairie dogs

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Abbott, Rachel C.; Russell, Robin E.; Richgels, Katherine; Tripp, Daniel W.; Matchett, Marc R.; Biggins, Dean E.; Rocke, Tonie E.

2017-01-01

Sylvatic plague vaccine (SPV) is a virally vectored bait-delivered vaccine expressing Yersinia pestis antigens that can protect prairie dogs (Cynomys spp.) from plague and has potential utility as a management tool. In a large-scale 3-year field trial, SPV-laden baits containing the biomarker rhodamine B (used to determine bait consumption) were distributed annually at a rate of approximately 100–125 baits/hectare along transects at 58 plots encompassing the geographic ranges of four species of prairie dogs. We assessed site- and individual-level factors related to bait uptake in prairie dogs to determine which were associated with bait uptake rates. Overall bait uptake for 7820 prairie dogs sampled was 70% (95% C.I. 69.9–72.0). Factors influencing bait uptake rates by prairie dogs varied by species, however, in general, heavier animals had greater bait uptake rates. Vegetation quality and day of baiting influenced this relationship for black-tailed, Gunnison’s, and Utah prairie dogs. For these species, baiting later in the season, when normalized difference vegetation indices (a measure of green vegetation density) are lower, improves bait uptake by smaller animals. Consideration of these factors can aid in the development of species-specific SPV baiting strategies that maximize bait uptake and subsequent immunization of prairie dogs against plague.

Spatial distribution patterns of plague hosts : point pattern analysis of the burrows of great gerbils in Kazakhstan

NARCIS (Netherlands)

Wilschut, Liesbeth I; Laudisoit, Anne; Hughes, Nelika K; Addink, Elisabeth A; de Jong, Steven M; Heesterbeek, Hans A P; Reijniers, Jonas; Eagle, Sally; Dubyanskiy, Vladimir M; Begon, Mike

AIM: The spatial structure of a population can strongly influence the dynamics of infectious diseases, yet rarely is the underlying structure quantified. A case in point is plague, an infectious zoonotic disease caused by the bacterium Yersinia pestis. Plague dynamics within the Central Asian desert

[IMPACT OF CASPIAN SEA LEVEL FLUCTUATIONS ON THE EPIZOOTIC ACTIVITY OF THE CASPIAN SANDY NATURAL PLAGUE FOCUS].

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Popov, N V; Udovikov, A I; Eroshenko, G A; Karavaeva, T B; Yakovlev, S A; Porshakov, A M; Zenkevich, E S; Kutyrev, V V

2016-01-01

There is evidence that in 1923-2014 the sharp aggravations of the epizootic situation of plague in the area of its Caspian sandy natural focus after long interepizootic periods are in time with the ups of the Caspian Sea in the extrema of 11-year solar cycles. There were cases of multiple manifestations of plague in the same areas in the epizootic cycles of 1946-1954, 1979-1996, 2001, and 2013-2014. The paper considers the possible role of amebae of the genus Acanthamoeba and nematodes, the representatives of the orders Rhabditida and Tylenchida in the microfocal pattern of plague manifestations.

The human-bacterial pathogen protein interaction networks of Bacillus anthracis, Francisella tularensis, and Yersinia pestis.

Directory of Open Access Journals (Sweden)

Matthew D Dyer

2010-08-01

Full Text Available Bacillus anthracis, Francisella tularensis, and Yersinia pestis are bacterial pathogens that can cause anthrax, lethal acute pneumonic disease, and bubonic plague, respectively, and are listed as NIAID Category A priority pathogens for possible use as biological weapons. However, the interactions between human proteins and proteins in these bacteria remain poorly characterized leading to an incomplete understanding of their pathogenesis and mechanisms of immune evasion.In this study, we used a high-throughput yeast two-hybrid assay to identify physical interactions between human proteins and proteins from each of these three pathogens. From more than 250,000 screens performed, we identified 3,073 human-B. anthracis, 1,383 human-F. tularensis, and 4,059 human-Y. pestis protein-protein interactions including interactions involving 304 B. anthracis, 52 F. tularensis, and 330 Y. pestis proteins that are uncharacterized. Computational analysis revealed that pathogen proteins preferentially interact with human proteins that are hubs and bottlenecks in the human PPI network. In addition, we computed modules of human-pathogen PPIs that are conserved amongst the three networks. Functionally, such conserved modules reveal commonalities between how the different pathogens interact with crucial host pathways involved in inflammation and immunity.These data constitute the first extensive protein interaction networks constructed for bacterial pathogens and their human hosts. This study provides novel insights into host-pathogen interactions.

Integrating land cover and terrain characteristics to explain plague ...

African Journals Online (AJOL)

Literature suggests that higher resolution remote sensing data integrated in Geographic Information System (GIS) can provide greater possibility to refine the analysis of land cover and terrain characteristics for explanation of abundance and distribution of plague hosts and vectors and hence of health risk hazards to ...

Temporal Progression of Pneumonic Plague in Blood of Nonhuman Primate: A Transcriptomic Analysis.

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Rasha Hammamieh

Full Text Available Early identification of impending illness during widespread exposure to a pathogenic agent offers a potential means to initiate treatment during a timeframe when it would be most likely to be effective and has the potential to identify novel therapeutic strategies. The latter could be critical, especially as antibiotic resistance is becoming widespread. In order to examine pre-symptomatic illness, African green monkeys were challenged intranasally with aerosolized Yersinia pestis strain CO92 and blood samples were collected in short intervals from 45 m till 42 h post-exposure. Presenting one of the first genomic investigations of a NHP model challenged by pneumonic plague, whole genome analysis was annotated in silico and validated by qPCR assay. Transcriptomic profiles of blood showed early perturbation with the number of differentially expressed genes increasing until 24 h. By then, Y. pestis had paralyzed the host defense, as suggested by the functional analyses. Early activation of the apoptotic networks possibly facilitated the pathogen to overwhelm the defense mechanisms, despite the activation of the pro-inflammatory mechanism, toll-like receptors and microtubules at the port-of-entry. The overexpressed transcripts encoding an early pro-inflammatory response particularly manifested in active lymphocytes and ubiquitin networks were a potential deviation from the rodent models, which needs further verification. In summary, the present study recognized a pattern of Y. pestis pathogenesis potentially more applicable to the human system. Independent validation using the complementary omics approach with comprehensive evaluation of the organs, such as lungs which showed early bacterial infection, is essential.

The Asian house shrew Suncus murinus as a reservoir and source of human outbreaks of plague in Madagascar.

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Rahelinirina, Soanandrasana; Rajerison, Minoarisoa; Telfer, Sandra; Savin, Cyril; Carniel, Elisabeth; Duplantier, Jean-Marc

2017-11-01

Identifying key reservoirs for zoonoses is crucial for understanding variation in incidence. Plague re-emerged in Mahajanga, Madagascar in the 1990s but there has been no confirmed case since 1999. Here we combine ecological and genetic data, from during and after the epidemics, with experimental infections to examine the role of the shrew Suncus murinus in the plague epidemiological cycle. The predominance of S. murinus captures during the epidemics, their carriage of the flea vector and their infection with Yersinia pestis suggest they played an important role in the maintenance and transmission of plague. S. murinus exhibit a high but variable resistance to experimental Y. pestis infections, providing evidence of its ability to act as a maintenance host. Genetic analyses of the strains isolated from various hosts were consistent with two partially-linked transmission cycles, with plague persisting within the S. murinus population, occasionally spilling over into the rat and human populations. The recent isolation from a rat in Mahajanga of a Y. pestis strain genetically close to shrew strains obtained during the epidemics reinforces this hypothesis and suggests circulation of plague continues. The observed decline in S. murinus and Xenopsylla cheopis since the epidemics appears to have decreased the frequency of spillover events to the more susceptible rats, which act as a source of infection for humans. Although this may explain the lack of confirmed human cases in recent years, the current circulation of plague within the city highlights the continuing health threat.

Importance of small fishes and invasive crayfish in otter Lutra lutra diet in an English chalk stream

OpenAIRE

Britton, J.R.; Berry, M.; Sewell, S.; Lees, C.; Reading, P.

2017-01-01

The diet composition of the European otter Lutra lutra was assessed using spraint analysis in the Hampshire Avon, a lowland chalk stream in Southern England, over an 18-month period. Small cyprinid fishes were the main prey item taken in all seasons, with bullhead Cottus gobio and stone loach Barbatula barbatula also important; there were relatively few larger fishes of interest to fisheries found. There were significant seasonal differences in diet composition by season, with signal crayfish...

CRAYFISH PREDATION EXPERIMENTS ON THE INTRODUCED ZEBRA MUSSEL, DREISSENA POLYMORPHA, IN IRELAND, AND THEIR POTENTIAL FOR BIOCONTROL.

OpenAIRE

REYNOLDS J. D.; DONOHOE R.

2001-01-01

The zebra mussel Dreissena polymorpha, native to the Aralo-Caspian region, has spread across Europe in the last 180 years. Although it reached England in 1820, it only arrived in Ireland in around 1995, probably attached to the hull of pleasure boats, and since then has spread through the lowland Shannon and Erne systems, which are linked by canal. While White-clawed crayfish Austropotamobius pallipes (Lereboullet) occur in these systems, Dreissena has not yet colonized sites with large crayf...

Distinct CCR2(+) Gr1(+) cells control growth of the Yersinia pestis ΔyopM mutant in liver and spleen during systemic plague.

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Ye, Zhan; Uittenbogaard, Annette M; Cohen, Donald A; Kaplan, Alan M; Ambati, Jayakrishna; Straley, Susan C

2011-02-01

We are using a systemic plague model to identify the cells and pathways that are undermined by the virulence protein YopM of the plague bacterium Yersinia pestis. In this study, we pursued previous findings that Gr1(+) cells are required to selectively limit growth of ΔyopM Y. pestis and that CD11b(+) cells other than polymorphonuclear leukocytes (PMNs) are selectively lost in spleens infected with parent Y. pestis. When PMNs were ablated from mice, ΔyopM Y. pestis grew as well as the parent strain in liver but not in spleen, showing that these cells are critical for controlling growth of the mutant in liver but not spleen. In mice lacking expression of the chemokine receptor CCR2, wild-type growth was restored to ΔyopM Y. pestis in both organs. In spleen, the Gr1(+) cells differentially recruited by parent and ΔyopM Y. pestis infections were CCR2(+) Gr1(+) CD11b(+) CD11c(Lo-Int) MAC3(+) iNOS(+) (inducible nitric oxide synthase-positive) inflammatory dendritic cells (iDCs), and their recruitment to spleen from blood was blocked when YopM was present in the infecting strain. Consistent with influx of iDCs being affected by YopM in spleen, the growth defect of the ΔyopM mutant was relieved by the parent Y. pestis strain in a coinfection assay in which the parent strain could affect the fate of the mutant in trans. In a mouse model of bubonic plague, CCR2 also was shown to be required for ΔyopM Y. pestis to show wild-type growth in skin. The data imply that YopM's pathogenic effect indirectly undermines signaling through CCR2. We propose a model for how YopM exerts its different effects in liver and spleen.

New Insights into How Yersinia pestis Adapts to Its Mammalian Host during Bubonic Plague

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Pradel, Elizabeth; Lemaître, Nadine; Merchez, Maud; Ricard, Isabelle; Reboul, Angéline; Dewitte, Amélie; Sebbane, Florent

2014-01-01

Bubonic plague (a fatal, flea-transmitted disease) remains an international public health concern. Although our understanding of the pathogenesis of bubonic plague has improved significantly over the last few decades, researchers have still not been able to define the complete set of Y. pestis genes needed for disease or to characterize the mechanisms that enable infection. Here, we generated a library of Y. pestis mutants, each lacking one or more of the genes previously identified as being up-regulated in vivo. We then screened the library for attenuated virulence in rodent models of bubonic plague. Importantly, we tested mutants both individually and using a novel, “per-pool” screening method that we have developed. Our data showed that in addition to genes involved in physiological adaption and resistance to the stress generated by the host, several previously uncharacterized genes are required for virulence. One of these genes (ympt1.66c, which encodes a putative helicase) has been acquired by horizontal gene transfer. Deletion of ympt1.66c reduced Y. pestis' ability to spread to the lymph nodes draining the dermal inoculation site – probably because loss of this gene decreased the bacteria's ability to survive inside macrophages. Our results suggest that (i) intracellular survival during the early stage of infection is important for plague and (ii) horizontal gene transfer was crucial in the acquisition of this ability. PMID:24675805

New insights into how Yersinia pestis adapts to its mammalian host during bubonic plague.

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Elizabeth Pradel

2014-03-01

Full Text Available Bubonic plague (a fatal, flea-transmitted disease remains an international public health concern. Although our understanding of the pathogenesis of bubonic plague has improved significantly over the last few decades, researchers have still not been able to define the complete set of Y. pestis genes needed for disease or to characterize the mechanisms that enable infection. Here, we generated a library of Y. pestis mutants, each lacking one or more of the genes previously identified as being up-regulated in vivo. We then screened the library for attenuated virulence in rodent models of bubonic plague. Importantly, we tested mutants both individually and using a novel, "per-pool" screening method that we have developed. Our data showed that in addition to genes involved in physiological adaptation and resistance to the stress generated by the host, several previously uncharacterized genes are required for virulence. One of these genes (ympt1.66c, which encodes a putative helicase has been acquired by horizontal gene transfer. Deletion of ympt1.66c reduced Y. pestis' ability to spread to the lymph nodes draining the dermal inoculation site--probably because loss of this gene decreased the bacteria's ability to survive inside macrophages. Our results suggest that (i intracellular survival during the early stage of infection is important for plague and (ii horizontal gene transfer was crucial in the acquisition of this ability.

Potential role of viruses in white plague coral disease.

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Soffer, Nitzan; Brandt, Marilyn E; Correa, Adrienne M S; Smith, Tyler B; Thurber, Rebecca Vega

2014-02-01

White plague (WP)-like diseases of tropical corals are implicated in reef decline worldwide, although their etiological cause is generally unknown. Studies thus far have focused on bacterial or eukaryotic pathogens as the source of these diseases; no studies have examined the role of viruses. Using a combination of transmission electron microscopy (TEM) and 454 pyrosequencing, we compared 24 viral metagenomes generated from Montastraea annularis corals showing signs of WP-like disease and/or bleaching, control conspecific corals, and adjacent seawater. TEM was used for visual inspection of diseased coral tissue. No bacteria were visually identified within diseased coral tissues, but viral particles and sequence similarities to eukaryotic circular Rep-encoding single-stranded DNA viruses and their associated satellites (SCSDVs) were abundant in WP diseased tissues. In contrast, sequence similarities to SCSDVs were not found in any healthy coral tissues, suggesting SCSDVs might have a role in WP disease. Furthermore, Herpesviridae gene signatures dominated healthy tissues, corroborating reports that herpes-like viruses infect all corals. Nucleocytoplasmic large DNA virus (NCLDV) sequences, similar to those recently identified in cultures of Symbiodinium (the algal symbionts of corals), were most common in bleached corals. This finding further implicates that these NCLDV viruses may have a role in bleaching, as suggested in previous studies. This study determined that a specific group of viruses is associated with diseased Caribbean corals and highlights the potential for viral disease in regional coral reef decline.

Tracking the invasion of the red swamp crayfish Procambarus clarkii (Girard, 1852 (Decapoda Cambaridae in Sicily: a “citizen science” approach

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Francesco Paolo Faraone

2017-11-01

Full Text Available The first record of the red swamp crayfish in Sicily dates back to 2003 and, since then, the species seemed to be confined to a few localities in western Sicily. A small “citizen science” project carried out from November 2016 onwards led to the creation of the “Sicilian Procambarus working group” (SPwg, which aims at monitoring the distribution and impact of the species in Sicily. To date, the SPwg found the red swamp crayfish in five new sites on the island, thus doubling the number of local sites of occurrence. The new Procambarus clarkii sites lie in different river basins, some of them located several hundred kilometres from the invaded areas known to date, suggesting the existence of multiple independent releases of the species in the wild. The need of better informing the local population on the risks exerted by invasive species on biological diversity, and of carefully monitoring the impact of P. clarkii on the Sicilian inland water biota is briefly stressed.

Plague Circulation and Population Genetics of the Reservoir Rattus rattus: The Influence of Topographic Relief on the Distribution of the Disease within the Madagascan Focus

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Brouat, Carine; Rahelinirina, Soanandrasana; Loiseau, Anne; Rahalison, Lila; Rajerison, Minoariso; Laffly, Dominique; Handschumacher, Pascal; Duplantier, Jean-Marc

2013-01-01

Background Landscape may affect the distribution of infectious diseases by influencing the population density and dispersal of hosts and vectors. Plague (Yersinia pestis infection) is a highly virulent, re-emerging disease, the ecology of which has been scarcely studied in Africa. Human seroprevalence data for the major plague focus of Madagascar suggest that plague spreads heterogeneously across the landscape as a function of the relief. Plague is primarily a disease of rodents. We therefore investigated the relationship between disease distribution and the population genetic structure of the black rat, Rattus rattus, the main reservoir of plague in Madagascar. Methodology/Principal Findings We conducted a comparative study of plague seroprevalence and genetic structure (15 microsatellite markers) in rat populations from four geographic areas differing in topology, each covering about 150–200 km2 within the Madagascan plague focus. The seroprevalence levels in the rat populations mimicked those previously reported for humans. As expected, rat populations clearly displayed a more marked genetic structure with increasing relief. However, the relationship between seroprevalence data and genetic structure differs between areas, suggesting that plague distribution is not related everywhere to the effective dispersal of rats. Conclusions/Significance Genetic diversity estimates suggested that plague epizootics had only a weak impact on rat population sizes. In the highlands of Madagascar, plague dissemination cannot be accounted for solely by the effective dispersal of the reservoir. Human social activities may also be involved in spreading the disease in rat and human populations. PMID:23755317

Identification of Risk Factors Associated with Transmission of Plague Disease in Eastern Zambia.

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Nyirenda, Stanley S; Hang'ombe, Bernard M; Machang'u, Robert; Mwanza, Jackson; Kilonzo, Bukheti S

2017-09-01

Plague is a fatal, primarily rodent-flea-borne zoonotic disease caused by Yersinia pestis . The identification of risk factors of plague was investigated through questionnaire interview and conducting focus group discussion (FGD) in Sinda and Nyimba districts of eastern Zambia. A total of 104 questionnaires were administered to individual respondents and 20 groups consisting of 181 discussants, which comprised FGD team in this study. The study revealed that trapping, transportation, and preparation of rodents for food exposed the community to rodent and their fleas suggesting that plague may have occurred primarily by either flea bites or contact with infected wild rodents. The study also revealed that most people in communities consumed rodents as part of their regular diet; therefore, contact with small wild mammals was a common practice. The mode of transportation of freshly trapped rodents, in particular, carcasses risked human to flea bites. Questionnaire respondents (75%) and FGD discussants (55%) indicated that trappers preferred to carry rodent carcasses in small bags, whereas 55.8% and 20% respectively, reported hunters carrying carcasses in their pockets. Carrying of carcass skewers on trappers' shoulders was reported by 38.4% and 20% of individual respondents and FGD, respectively. All these activities were exposing humans to rodents and their fleas, the natural reservoirs and vectors of plague, respectively. This study also showed that there is a statistically significant (χ 2 = 4.6878, P < 0.05), between digging of rodents from their burrows and the presence of fleas on the hunter's bodies or clothes, which exposes humans to potentially flea bites in an enzootic cycle.

[Plague outbreaks in the Mediterranean area during the 2nd World War, epidemiology and treatments].

Science.gov (United States)

Mafart, B; Brisou, P; Bertherat, E

2004-11-01

Before the Second World War, the plague was still rife in North Africa but occurred only as sporadic cases or small outbreaks as in Egypt or Morocco. The permanent foci of infected wild rodent were the cause of these rural outbreaks. In 1943 and 1944, plague came back in several Mediterranean towns and ports and was considered as a serious danger for the Allied Forces. These resurgences were related to the World War as well as the overpopulation of the cities, regroupings and population movements, relaxation of prophylactic measures of the plague in sea transport. The Allied Forces medical officers then showed the resistance of Yersinia pestis to penicillin which they had been supplied with recently, the effectiveness of sulphamides but mortality remained high (27%). In parallel, the drastic fight against rodents and fleas (DDT) gave excellent results.

The Asian house shrew Suncus murinus as a reservoir and source of human outbreaks of plague in Madagascar.

Directory of Open Access Journals (Sweden)

Soanandrasana Rahelinirina

2017-11-01

Full Text Available Identifying key reservoirs for zoonoses is crucial for understanding variation in incidence. Plague re-emerged in Mahajanga, Madagascar in the 1990s but there has been no confirmed case since 1999. Here we combine ecological and genetic data, from during and after the epidemics, with experimental infections to examine the role of the shrew Suncus murinus in the plague epidemiological cycle. The predominance of S. murinus captures during the epidemics, their carriage of the flea vector and their infection with Yersinia pestis suggest they played an important role in the maintenance and transmission of plague. S. murinus exhibit a high but variable resistance to experimental Y. pestis infections, providing evidence of its ability to act as a maintenance host. Genetic analyses of the strains isolated from various hosts were consistent with two partially-linked transmission cycles, with plague persisting within the S. murinus population, occasionally spilling over into the rat and human populations. The recent isolation from a rat in Mahajanga of a Y. pestis strain genetically close to shrew strains obtained during the epidemics reinforces this hypothesis and suggests circulation of plague continues. The observed decline in S. murinus and Xenopsylla cheopis since the epidemics appears to have decreased the frequency of spillover events to the more susceptible rats, which act as a source of infection for humans. Although this may explain the lack of confirmed human cases in recent years, the current circulation of plague within the city highlights the continuing health threat.

Multiple mechanisms of transmission of the Caribbean coral disease white plague

Science.gov (United States)

Clemens, E.; Brandt, M. E.

2015-12-01

White plague is one of the most devastating coral diseases in the Caribbean, and yet important aspects of its epidemiology, including how the disease transmits, remain unknown. This study tested potential mechanisms and rates of transmission of white plague in a laboratory setting. Transmission mechanisms including the transport of water, contact with macroalgae, and predation via corallivorous worms and snails were tested on the host species Orbicella annularis. Two of the tested mechanisms were shown to transmit disease: water transport and the corallivorous snail Coralliophila abbreviata. Between these transmission mechanisms, transport of water between a diseased coral and a healthy coral resulted in disease incidence significantly more frequently in exposed healthy corals. Transmission via water transport also occurred more quickly and was associated with higher rates of tissue loss (up to 3.5 cm d-1) than with the corallivorous snail treatment. In addition, water that was in contact with diseased corals but was filtered with a 0.22-μm filter prior to being introduced to apparently healthy corals also resulted in the transmission of disease signs, but at a much lower rate than when water was not filtered. This study has provided important information on the transmission potential of Caribbean white plague disease and highlights the need for a greater understanding of how these processes operate in the natural environment.

Quinto Tiberio Angelerio and New Measures for Controlling Plague in 16th-Century Alghero, Sardinia

OpenAIRE

Bianucci, Raffaella; Benedictow, Ole J?rgen; Fornaciari, Gino; Giuffra, Valentina

2013-01-01

Plague, a zoonotic disease caused by the bacterium Yersinia pestis, has been responsible for at least 3 pandemics. During 1582?1583, a plague outbreak devastated the seaport of Alghero in Sardinia. By analyzing contemporary medical texts and local documentation, we uncovered the pivotal role played by the Protomedicus of Alghero, Quinto Tiberio Angelerio (1532?1617), in controlling the epidemic. Angelerio imposed rules and antiepidemic measures new to the 16th-century sanitary system of Sardi...

Determination of mercury by cold-vapor technique in several tissues of treated American red crayfish (Procambarus clarkii)

Energy Technology Data Exchange (ETDEWEB)

Del Ramo, J.; Pastor, A.; Diaz-Mayans, J.; Medina, J.; Torreblanca, A.

1988-01-01

Adult intermolt specimens of American red crayfish (Procambarus clarkii) collected from Lake Albufera (Valencia, Spain), were exposed to mercury during 96 h. The Hg-concentrations used were 50, 100, and 250 ..mu..g Hg/l as Cl/sub 2/Hg. The content of mercury in muscle, midgut gland, antennal glands and gills was investigated. Determinations of mercury were made by cold-vapor technique and AAS. The mercury levels in all examined tissues increased significantly with increasing Hg-concentration in the water.

Effect of calcium on excitatory neuromuscular transmission in the crayfish

Science.gov (United States)

Bracho, H.; Orkand, R. K.

1970-01-01

1. The effects of varying the external Ca concentration from 1·8 to 30 mM/l. (⅛-2 times normal) have been studied at the in vitro crayfish excitatory neuromuscular junction. Electrophysiological techniques were used to record transmembrane junctional potentials from muscle fibres and extracellular junctional currents from the vicinity of nerve terminals. 2. The excitatory junctional potential amplitude was proportional to [Ca]0n, where n varied between 0·68 and 0·94 (mean 0·82) when [Ca]0 was varied from 1·8 to 15 mM/l. 3. The increase in junctional potential amplitude on raising [Ca]0 resulted primarily from an increase in the average number of quanta of excitatory transmitter released from the presynaptic nerve terminal by the nerve impulse. 4. The size of the quanta, synaptic delay, presynaptic potential and electrical properties of the muscle membrane were little affected by changes in calcium concentration in the range studied. PMID:5498460

Identifying the social and environmental determinants of plague endemicity in Peru: insights from a case study in Ascope, La Libertad.

Science.gov (United States)

Rivière-Cinnamond, Ana; Santandreu, Alain; Luján, Anita; Mertens, Frederic; Espinoza, John Omar; Carpio, Yesenia; Bravo, Johnny; Gabastou, Jean-Marc

2018-02-06

Plague remains a public health problem in specific areas located in Bolivia, Brazil, Ecuador and Peru. Its prevention and control encompasses adequate clinical management and timely laboratory diagnosis. However, understanding communities' interaction with its surrounding ecosystem as well as the differences between community members and institutional stakeholders regarding the root causes of plague might contribute to understand its endemicity. We aim at bridging the traditionally separate biological and social sciences by elucidating communities' risk perception and identifying knowledge gaps between communities and stakeholders. This approach has been used in other areas but never in understanding plague endemicity, nor applied in the Latin American plague context. The objectives were to identify (i) plague risk perception at community level, (ii) perceived social and environmental determinants of plague endemicity, and (iii) institutions that need to be involved and actions needed to be taken as proposed by stakeholders and community members. The study was performed in 2015 and took place in Ascope rural province, La Libertad Region, in Peru, where the study areas are surrounded by intensive private sugarcane production. We propose using a multi-level discourse analysis. Community households were randomly selected (n = 68). Structured and semi-structured questionnaires were applied. A stakeholder analysis was used to identify policy makers (n = 34). In-depth interviews were performed, recorded and transcribed. Descriptive variables were analyzed with SPSS®. Answers were coded following variables adapted from the Commission on Social Determinants of Health and analyzed with the assistance of ATLAS.ti®. Results showed that risk perception was low within the community. Policy-makers identified agriculture and sugarcane production as the root cause while community answers ranked the hygiene situation as the main cause. Stakeholders first ranked

Validation of inverse seasonal peak mortality in medieval plagues, including the Black Death, in comparison to modern Yersinia pestis-variant diseases.

Science.gov (United States)

Welford, Mark R; Bossak, Brian H

2009-12-22

Recent studies have noted myriad qualitative and quantitative inconsistencies between the medieval Black Death (and subsequent "plagues") and modern empirical Y. pestis plague data, most of which is derived from the Indian and Chinese plague outbreaks of A.D. 1900+/-15 years. Previous works have noted apparent differences in seasonal mortality peaks during Black Death outbreaks versus peaks of bubonic and pneumonic plagues attributed to Y. pestis infection, but have not provided spatiotemporal statistical support. Our objective here was to validate individual observations of this seasonal discrepancy in peak mortality between historical epidemics and modern empirical data. We compiled and aggregated multiple daily, weekly and monthly datasets of both Y. pestis plague epidemics and suspected Black Death epidemics to compare seasonal differences in mortality peaks at a monthly resolution. Statistical and time series analyses of the epidemic data indicate that a seasonal inversion in peak mortality does exist between known Y. pestis plague and suspected Black Death epidemics. We provide possible explanations for this seasonal inversion. These results add further evidence of inconsistency between historical plagues, including the Black Death, and our current understanding of Y. pestis-variant disease. We expect that the line of inquiry into the disputed cause of the greatest recorded epidemic will continue to intensify. Given the rapid pace of environmental change in the modern world, it is crucial that we understand past lethal outbreaks as fully as possible in order to prepare for future deadly pandemics.

Early host cell targets of Yersinia pestis during primary pneumonic plague.

Directory of Open Access Journals (Sweden)

Roger D Pechous

Full Text Available Inhalation of Yersinia pestis causes primary pneumonic plague, a highly lethal syndrome with mortality rates approaching 100%. Pneumonic plague progression is biphasic, with an initial pre-inflammatory phase facilitating bacterial growth in the absence of host inflammation, followed by a pro-inflammatory phase marked by extensive neutrophil influx, an inflammatory cytokine storm, and severe tissue destruction. Using a FRET-based probe to quantitate injection of effector proteins by the Y. pestis type III secretion system, we show that these bacteria target alveolar macrophages early during infection of mice, followed by a switch in host cell preference to neutrophils. We also demonstrate that neutrophil influx is unable to limit bacterial growth in the lung and is ultimately responsible for the severe inflammation during the lethal pro-inflammatory phase.

Isolation and Suffering Related to Serious and Terminal Illness: Metaphors and Lessons From Albert Camus' Novel, The Plague.

Science.gov (United States)

Tuffuor, Akosua N; Payne, Richard

2017-09-01

Health care providers have much to learn from Albert Camus' great novel, The Plague. The Plague tells the story of a bubonic plague epidemic through the lens of doctor-narrator Rieux. In addition to Rieux, this essay also focuses on the perspective of Father Paneloux, a Jesuit priest, who provides important religious commentary on the epidemic, before falling victim to it and dying. Camus' masterful engagement of the metaphor of isolation and its profound impact on suffering emphasizes the important role of community and spiritual perspectives of patients and providers in coping with serious illness, death, and dying. The Plague is relevant today, particularly given the challenges of distancing, alienation, and isolation imposed by not only disease but also by technology and clinical and administrative practices that have unintended consequences of incentivizing separation between patient and healer, thus engendering greater stress and suffering in both. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Recombinant raccoon pox vaccine protects mice against lethal plague

Science.gov (United States)

Osorio, J.E.; Powell, T.D.; Frank, R.S.; Moss, K.; Haanes, E.J.; Smith, S.R.; Rocke, T.E.; Stinchcomb, D.T.

2003-01-01

Using a raccoon poxvirus (RCN) expression system, we have developed new recombinant vaccines that can protect mice against lethal plague infection. We tested the effects of a translation enhancer (EMCV-IRES) in combination with a secretory (tPA) signal or secretory (tPA) and membrane anchoring (CHV-gG) signals on in vitro antigen expression of F1 antigen in tissue culture and the induction of antibody responses and protection against Yersinia pestis challenge in mice. The RCN vector successfully expressed the F1 protein of Y. pestis in vitro. In addition, the level of expression was increased by the insertion of the EMCV-IRES and combinations of this and the secretory signal or secretory and anchoring signals. These recombinant viruses generated protective immune responses that resulted in survival of 80% of vaccinated mice upon challenge with Y. pestis. Of the RCN-based vaccines we tested, the RCN-IRES-tPA-YpF1 recombinant construct was the most efficacious. Mice vaccinated with this construct withstood challenge with as many as 1.5 million colony forming units of Y. pestis (7.7×104 LD50). Interestingly, vaccination with F1 fused to the anchoring signal (RCN-IRES-tPA-YpF1-gG) elicited significant anti-F1 antibody titers, but failed to protect mice from plague challenge. Our studies demonstrate, in vitro and in vivo, the potential importance of the EMCV-IRES and secretory signals in vaccine design. These molecular tools provide a new approach for improving the efficacy of vaccines. In addition, these novel recombinant vaccines could have human, veterinary, and wildlife applications in the prevention of plague.

Vegetation habitats and small mammals in a plague endemic area ...

African Journals Online (AJOL)

Keywords: plague, vegetation, habitats, rodents distribution, Tanzania ... diseases (Eisen et al., 2007), and for the development of pest management .... This study received approval from Directorate of Research and Post-Graduate Studies of ..... be explained by the nature of human activities including grazing, bush fires, fire.

Coregulation of host-adapted metabolism and virulence by pathogenic yersiniae

Science.gov (United States)

Heroven, Ann Kathrin; Dersch, Petra

2014-01-01

Deciphering the principles how pathogenic bacteria adapt their metabolism to a specific host microenvironment is critical for understanding bacterial pathogenesis. The enteric pathogenic Yersinia species Yersinia pseudotuberculosis and Yersinia enterocolitica and the causative agent of plague, Yersinia pestis, are able to survive in a large variety of environmental reservoirs (e.g., soil, plants, insects) as well as warm-blooded animals (e.g., rodents, pigs, humans) with a particular preference for lymphatic tissues. In order to manage rapidly changing environmental conditions and interbacterial competition, Yersinia senses the nutritional composition during the course of an infection by special molecular devices, integrates this information and adapts its metabolism accordingly. In addition, nutrient availability has an impact on expression of virulence genes in response to C-sources, demonstrating a tight link between the pathogenicity of yersiniae and utilization of nutrients. Recent studies revealed that global regulatory factors such as the cAMP receptor protein (Crp) and the carbon storage regulator (Csr) system are part of a large network of transcriptional and posttranscriptional control strategies adjusting metabolic changes and virulence in response to temperature, ion and nutrient availability. Gained knowledge about the specific metabolic requirements and the correlation between metabolic and virulence gene expression that enable efficient host colonization led to the identification of new potential antimicrobial targets. PMID:25368845

Histopathological observation of immunized rhesus macaques with plague vaccines after subcutaneous infection of Yersinia pestis.

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Guang Tian

Full Text Available In our previous study, complete protection was observed in Chinese-origin rhesus macaques immunized with SV1 (20 µg F1 and 10 µg rV270 and SV2 (200 µg F1 and 100 µg rV270 subunit vaccines and with EV76 live attenuated vaccine against subcutaneous challenge with 6×10(6 CFU of Y. pestis. In the present study, we investigated whether the vaccines can effectively protect immunized animals from any pathologic changes using histological and immunohistochemical techniques. In addition, the glomerular basement membranes (GBMs of the immunized animals and control animals were checked by electron microscopy. The results show no signs of histopathological lesions in the lungs, livers, kidneys, lymph nodes, spleens and hearts of the immunized animals at Day 14 after the challenge, whereas pathological alterations were seen in the corresponding tissues of the control animals. Giemsa staining, ultrastructural examination, and immunohistochemical staining revealed bacteria in some of the organs of the control animals, whereas no bacterium was observed among the immunized animals. Ultrastructural observation revealed that no glomerular immune deposits on the GBM. These observations suggest that the vaccines can effectively protect animals from any pathologic changes and eliminate Y. pestis from the immunized animals. The control animals died from multi-organ lesions specifically caused by the Y. pestis infection. We also found that subcutaneous infection of animals with Y. pestis results in bubonic plague, followed by pneumonic and septicemic plagues. The histopathologic features of plague in rhesus macaques closely resemble those of rodent and human plagues. Thus, Chinese-origin rhesus macaques serve as useful models in studying Y. pestis pathogenesis, host response and the efficacy of new medical countermeasures against plague.

Deltamethrin flea-control preserves genetic variability of black-tailed prairie dogs during a plague outbreak

Science.gov (United States)

Jones, P.H.; Biggins, D.E.; Eads, D.A.; Eads, S.L.; Britten, H.B.

2012-01-01

Genetic variability and structure of nine black-tailed prairie dog (BTPD, Cynomys ludovicianus) colonies were estimated with 15 unlinked microsatellite markers. A plague epizootic occurred between the first and second years of sampling and our study colonies were nearly extirpated with the exception of three colonies in which prairie dog burrows were previously dusted with an insecticide, deltamethrin, used to control fleas (vectors of the causative agent of plague, Yersinia pestis). This situation provided context to compare genetic variability and structure among dusted and non-dusted colonies pre-epizootic, and among the three dusted colonies pre- and post-epizootic. We found no statistical difference in population genetic structures between dusted and non-dusted colonies pre-epizootic. On dusted colonies, gene flow and recent migration rates increased from the first (pre-epizootic) year to the second (post-epizootic) year which suggested dusted colonies were acting as refugia for prairie dogs from surrounding colonies impacted by plague. Indeed, in the dusted colonies, estimated densities of adult prairie dogs (including dispersers), but not juveniles (non-dispersers), increased from the first year to the second year. In addition to preserving BTPDs and many species that depend on them, protecting colonies with deltamethrin or a plague vaccine could be an effective method to preserve genetic variability of prairie dogs. ?? 2011 Springer Science+Business Media B.V.

Investigation of vesicle-capsular plague antigen complex formation by elastic laser radiation scattering

Science.gov (United States)

Guseva, N. P.; Maximova, Irina S.; Romanov, Sergey V.; Shubochkin, L. P.; Tatarintsev, Sergey N.

1991-05-01

Recently a great deal of attention has been given to the investigation artificial lipid liposomes, due to their application as "containers" for directed transport of biologically active compounds into particular cells, organs and tissues for prophylaxis and therapy of infectious diseases. The use of traditional methods of liposome investigation, such as sedimentation, electrophoresis and chromatography is impeded by low liposome resistivity to different deformations. In conjunction with this, optical methods of laser light scattering are promising as they allow nondisturbing, precise and quick investigations. This paper describes the investigation of vesicle systems prepared from egg lecithin of Serva Corporation and their complexes with the capsular antigen of the plague microbe. The capsular antigen Fl was obtained from EV plague microbe grown at 37° C on Huttinger agar. Fl was isolated by gel-filtration on ASA-22 followed by freeze drying of the preparation. Angular dependences of polarized radiation scattering were measured for several liposome suspension samples in a saline solution before and after the interaction with the plague microbe capsular antigen. The aim of the investigation was to analyze the nature of mutual antigen arrangement in a liposome and to develop methods for measuring its inclusion percentage.

Validation of inverse seasonal peak mortality in medieval plagues, including the Black Death, in comparison to modern Yersinia pestis-variant diseases.

Directory of Open Access Journals (Sweden)

Mark R Welford

Full Text Available BACKGROUND: Recent studies have noted myriad qualitative and quantitative inconsistencies between the medieval Black Death (and subsequent "plagues" and modern empirical Y. pestis plague data, most of which is derived from the Indian and Chinese plague outbreaks of A.D. 1900+/-15 years. Previous works have noted apparent differences in seasonal mortality peaks during Black Death outbreaks versus peaks of bubonic and pneumonic plagues attributed to Y. pestis infection, but have not provided spatiotemporal statistical support. Our objective here was to validate individual observations of this seasonal discrepancy in peak mortality between historical epidemics and modern empirical data. METHODOLOGY/PRINCIPAL FINDINGS: We compiled and aggregated multiple daily, weekly and monthly datasets of both Y. pestis plague epidemics and suspected Black Death epidemics to compare seasonal differences in mortality peaks at a monthly resolution. Statistical and time series analyses of the epidemic data indicate that a seasonal inversion in peak mortality does exist between known Y. pestis plague and suspected Black Death epidemics. We provide possible explanations for this seasonal inversion. CONCLUSIONS/SIGNIFICANCE: These results add further evidence of inconsistency between historical plagues, including the Black Death, and our current understanding of Y. pestis-variant disease. We expect that the line of inquiry into the disputed cause of the greatest recorded epidemic will continue to intensify. Given the rapid pace of environmental change in the modern world, it is crucial that we understand past lethal outbreaks as fully as possible in order to prepare for future deadly pandemics.

Detections of Yersinia pestis East of the Known Distribution of Active Plague in the United States.

Science.gov (United States)

Mize, Erica L; Britten, Hugh B

2016-02-01

We examined fleas collected from black-tailed prairie dog (Cynomys ludovicianus) burrows from 2009 through 2011 in five national park units east of the known distribution of active plague across the northern Great Plains for the presence of Yersinia pestis. Across all national park units, Oropsylla tuberculata and Oropsylla hirsuta were the most common fleas collected from prairie dog burrows, 42.4% and 56.9%, respectively, of the 3964 fleas collected from burrow swabbing. Using a nested PCR assay, we detected 200 Y. pestis-positive fleas from 3117 assays. In total, 6.4% of assayed fleas were Y. pestis positive and 13.9% of prairie dog burrows swabbed contained Y. pestis-positive fleas. Evidence of the presence of Y. pestis was observed at all national park units except Devils Tower National Monument in Wyoming. We detected the presence of Y. pestis without large die-offs, i.e., enzootic sylvatic plague, east of the known distribution of active plague and near the eastern edge of the present distribution of black-tailed prairie dogs. This study, in combination with previous work suggests that sylvatic plague likely occurs across the range of black-tailed prairie dogs and should now be treated as endemic across this range.

Plague Law or Martial Law?: Sinaloa and Baja California, 1902-1903

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Ana María Carrillo

2005-04-01

Full Text Available This paper analyzes the social importance of the plague epidemic that caught Sinaloa and Baja California,  Mexico, in 1902 and 1903. It describes the health campaign  that was organized, the first one —in Mexico— based on the recent scientific fields of microbiology, immunology and tropical medicine.  It was also the first one in which a state turned control of sanitary activities in to the federal government. The author shows that in this campaign, health personnel  and political authorities used persuasion and, above all, compulsion, and describes how the population resisted the health measures. She analyzes the contradictions between the different actors of the campaign, explains the causes of its success and points  out  that the 1902-1903 campaign against plague became a model for further health campaigns in Mexico.

Observations on the endemicity of plague in Karatu and Ngorongoro ...

African Journals Online (AJOL)

Commensal and field rodents and wild small carnivores were live-trapped in five villages of Karatu district and one settlement in the Ngorongoro Conservation Area in Ngorongoro district in Tanzania. Blood samples were taken and serologically tested for plague, using the Blocking ELISA technique. Some domestic dogs ...

Use of Rhodamine B as a biomarker for oral plague vaccination of prairie dogs

Science.gov (United States)

Fernandez, Julia Rodriguez-Ramos; Rocke, Tonie E.

2011-01-01

Oral vaccination against Yersinia pestis could provide a feasible approach for controlling plague in prairie dogs (Cynomys spp.) for conservation and public health purposes. Biomarkers are useful in wildlife vaccination programs to demonstrate exposure to vaccine baits. Rhodamine B (RB) was tested as a potential biomarker for oral plague vaccination because it allows nonlethal sampling of animals through hair, blood, and feces. We found that RB is an appropriate marker for bait uptake studies of C. ludovicianus) when used at concentrations 10 mg RB per kg target animal mass. Whiskers with follicles provided the best sample for RB detection.

Unreliability and the Animal Narrator in Richard Adams’s The Plague Dogs

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Anja Höing

2017-03-01

Full Text Available Richard Adams’s talking animal story The Plague Dogs (1978, with its deeply genre-atypical mode of narration, offers a multiplicity of avenues to explore the literary animal as animal. The story draws much of its power from the psychological complexity and related unreliability of both canine narrators, two research lab escapees gone feral. Both the terrier Snitter and the black mongrel Rowf are mentally ill and experience a highly subjective, part-fantastic world. In episodes of zero focalization, a sarcastic voice comments on the plot from the off, aggressively attacking a thoroughly anthropocentric superstructure the protagonists themselves are oblivious of, and presenting all that is normally constructed as “rational” in the implied reader’s world as a carnivalesque farce. Combining these equally unreliable narratives, The Plague Dogs creates a unique mixture of what Phelan (2007 calls “estranging” and “bonding” unreliability and brings to light the devastating consequences of anthropocentrism. The Plague Dogs not only defamiliarizes a genre usually committed to conventional means of storytelling, but the dominant Western conception of the status of animals in the world, showing that once we start to read the animal as animal, this sets into motion an avalanche of other concepts in need of re-reading, among them the very ones making up the fundamental pillars of Western societies’ anthropocentric self-conception.

A curve of thresholds governs plague epizootics in Central Asia

DEFF Research Database (Denmark)

Reijniers, Jonas; Davis, Stephen; Begon, Mike

2012-01-01

, it is common to assume a threshold defined by the ratio of vector and host abundances. Here, we show in contrast, both from field data and model simulations, that for plague (Yersinia pestis) in Kazakhstan, the invasion threshold quantity is based on the product of its host (Rhombomys opimus) and vector...

Ovid’s Aeginetan plague and the metamorphosis of the Georgics

NARCIS (Netherlands)

Heerink, M.A.J.

2011-01-01

The influence of the ancient literary tradition upon the Georgics is as broad as it is profound , but in Virgil’s highly allusive didactic poem, the description of the Noric cattle plague at the end of Georgics 3 holds a unique position. As R.F. THOMAS comments, "nowhere else does Virgil draw so

Outbreak of Human Pneumonic Plague with Dog-to-Human and Possible Human-to-Human Transmission--Colorado, June-July 2014.

Science.gov (United States)

Runfola, Janine K; House, Jennifer; Miller, Lisa; Colton, Leah; Hite, Donna; Hawley, Alex; Mead, Paul; Schriefer, Martin; Petersen, Jeannine; Casaceli, Colleen; Erlandson, Kristine M; Foster, Clayton; Pabilonia, Kristy L; Mason, Gary; Douglas, John M

2015-05-01

On July 8, 2014, the Colorado Department of Public Health and Environment (CDPHE) laboratory identified Yersinia pestis, the bacterium that causes plague, in a blood specimen collected from a man (patient A) hospitalized with pneumonia. The organism had been previously misidentified as Pseudomonas luteola by an automated system in the hospital laboratory. An investigation led by Tri-County Health Department (TCHD) revealed that patient A's dog had died recently with hemoptysis. Three other persons who had contact with the dog, one of whom also had contact with patient A, were ill with fever and respiratory symptoms, including two with radiographic evidence of pneumonia. Specimens from the dog and all three human contacts yielded evidence of acute Y. pestis infection. One of the pneumonia cases might have resulted through human-to-human transmission from patient A, which would be the first such event reported in the United States since 1924. This outbreak highlights 1) the need to consider plague in the differential diagnosis of ill domestic animals, including dogs, in areas where plague is endemic; 2) the limitations of automated diagnostic systems for identifying rare bacteria such as Y. pestis; and 3) the potential for milder plague illness in patients taking antimicrobial agents. Hospital laboratorians should be aware of the limitations of automated identification systems, and clinicians should suspect plague in patients with clinically compatible symptoms from whom P. luteola is isolated.

Yersinia pestis biovar Microtus strain 201, an avirulent strain to humans, provides protection against bubonic plague in rhesus macaques.

Science.gov (United States)

Zhang, Qingwen; Wang, Qiong; Tian, Guang; Qi, Zhizhen; Zhang, Xuecan; Wu, Xiaohong; Qiu, Yefeng; Bi, Yujing; Yang, Xiaoyan; Xin, Youquan; He, Jian; Zhou, Jiyuan; Zeng, Lin; Yang, Ruifu; Wang, Xiaoyi

2014-01-01

Yersinia pestis biovar Microtus is considered to be a virulent to larger mammals, including guinea pigs, rabbits and humans. It may be used as live attenuated plague vaccine candidates in terms of its low virulence. However, the Microtus strain's protection against plague has yet to be demonstrated in larger mammals. In this study, we evaluated the protective efficacy of the Microtus strain 201 as a live attenuated plague vaccine candidate. Our results show that this strain is highly attenuated by subcutaneous route, elicits an F1-specific antibody titer similar to the EV and provides a protective efficacy similar to the EV against bubonic plague in Chinese-origin rhesus macaques. The Microtus strain 201 could induce elevated secretion of both Th1-associated cytokines (IFN-γ, IL-2 and TNF-α) and Th2-associated cytokines (IL-4, IL-5, and IL-6), as well as chemokines MCP-1 and IL-8. However, the protected animals developed skin ulcer at challenge site with different severity in most of the immunized and some of the EV-immunized monkeys. Generally, the Microtus strain 201 represented a good plague vaccine candidate based on its ability to generate strong humoral and cell-mediated immune responses as well as its good protection against high dose of subcutaneous virulent Y. pestis challenge.

Response Function of the Crayfish Caudal Photoreceptor to Hydrodynamic Stimuli

Science.gov (United States)

Breite, Sally; Bahar, Sonya; Neiman, Alexander; Moss, Frank

2002-03-01

In its abdominal 6th ganglion the crayfish houses 2 light-sensitive neurons (caudal photoreceptors, or CPRs). It is known that these neurons work in tandem with a mechanosensory system of tiny hairs spread across the tailfan, which make synaptic contact with the photoreceptors. A stochastic resonance effect has been shown in this system in which light enhances the transduction of a weak, periodic mechanosensory (hydrodynamic) stimulus. It is not known, however, whether an optimal response from the CPR is induced by a single sine wave cycle or some other waveform. We have experimentally investigated this favorable waveform by driving a tailfan preparation with mechanical 10 Hz correlated Ornstein-Uhlenbeck noise and calculating the response function from the spike-triggered average of the applied noise waveform. We will discuss differences in the shape of the optimal waveform under dark and light conditions, as well as what seems to be a noticeable difference in the magnitude of the animals' response to a noisy stimulus in comparison with a periodic stimulus.

Clinical features of Haff disease and myositis after the consumption of boiled brackish water crayfish: a retrospective study of 96 cases at a single centre.

Science.gov (United States)

He, Fei; Ni, Jun; Huang, Jun-Ai; Liu, Yao; Wu, Chao; Wang, Jun

2018-05-08

The present study describes the difference in clinical features between the patients with Haff disease and crayfish-related myositis (CRM) after crayfish consumption. This was a single-centre, retrospective analysis at the Emergency Department of the Drum Tower Hospital of Nanjing University School of Medicine from July to August of 2016. The baseline information came from the Electronic Medical Record System at the institution. Totally 96 patients were included, of whom 52 patients were confirmed to have Haff disease and 44 patients were CRM. The illness predominately occurs in summer and most of them (55/96) are female. The primary clinical features are myalgia, muscle allodynia and back and body pain. Statistical differences in the baseline CK, CK-MB, myoglobin, and the WBC count exist between the Haff disease and CRM groups (P < 0.05). The serum levels of CK and CK-MB increase in the second (a median time 29.2 ± 7.4 h) or third day (a median time 54.8 ± 9.3 h) of disease course, and then rapidly decreased to normal levels, while the levels of myoglobin peak at the admission (a median time 7.7 ± 6.4 h) and became normal after admission. There were no fatalities or complications during this study. All 96 patients recovered in a week. Of them, 75 were followed-up within 1 month and none had recurrence. The Haff disease and CRM after boiled crayfish consumption reflect a different severity of muscle injury, and reveal similar clinical characteristics and most of the laboratory values. The overall prognosis of both is good.

The role and significance of Luo Zhiyuan's Shu yi hui bian in the history of plague in Lingnan (south of the five ridges).

Science.gov (United States)

Li, H; Lai, W

1999-04-01

Being the earliest monograph on plague in China, Luo Zhiyuan's Shu yi hui bian, not included in the National Catalogue of TCM Books, include the following contents: personal idea on the etiology of plague; Luo's friend Wu Xuanchang' unpublished Shu yu zhi fa on the treatment and manifestations of plague; Luo's specific recipe for plague based on medified Wang Qingren's Jie du huo xue decoction based on Wang Qingrens yi lin gai cuo; therapy for critical cases; many therapies applied on Lingnan, including experimental recipes, external therapy, preventive methods, and preventing recurrence methods; Luo's special administrating methods, including persisting day-and-night method, immediate persisting method, single-dose persisting method, and double-dose persisting method. He also gave several cured case records. His book, featuring unique idea with good effect, was repeatedly printed and extensively distributed, exerting influence, more or less, on the plague monographs of later ages, and occupying important position in the history of plague on Lingnan and the whole country as well. His idea of "that poisons and static blood" in pathogenesis and therapeutic principle of antitoxicity and activating blood is coincided with the results of present day clinical and laboratory studies. His administration of medicines is heuristic to the therapy of critical cases with Chinese medicaments and to the recognition of pathogenesis, etiology, and treatment of modern plague as well as other diseases of similar etiology and pathognesis and is worth of further study.

Human bubonic plague transmitted by a domestic cat scratch.

Science.gov (United States)

Weniger, B G; Warren, A J; Forseth, V; Shipps, G W; Creelman, T; Gorton, J; Barnes, A M

1984-02-17

Bubonic plague was transmitted to a 10-year-old girl in Oregon by a scratch wound inflicted by a domestic cat. The cat probably was infected by contact with infected wild rodents or their fleas. Yersinia pestis was identified in Diamanus montanus fleas collected from an abandoned burrow near the patient's home. Domestic cats may infect humans with Y pestis by inoculation from a scratch.

Discovery of a leptospirosis cluster amidst a pneumonic plague outbreak in a miners' camp in the Democratic Republic of the Congo.

Science.gov (United States)

Bertherat, Eric; Mueller, Melissa J; Shako, Jean-Christophe; Picardeau, Mathieu

2014-02-07

Conditions in the Democratic Republic of the Congo provide an ideal environment for leptospirosis and plague, both of which can cause severe pulmonary manifestations. In December 2004, an outbreak of lethal pneumonia occurred in a local mining camp, affecting 130 persons and killing 57 of them. Clinical signs, fast disease spread, and initial laboratory investigations suggested pneumonic plague. While leptospirosis had not recently been described in the region, it was considered as a differential diagnosis. Anti-Leptospira antibodies were detected by microscopic agglutination test (MAT). A confirmed case of leptospirosis was defined as having consistent clinical signs and any one of the following: seroconversion or four-fold increase in MAT titre for paired serum samples, or a MAT titre ≥ 1:400 for acute-phase serum samples. Twenty-nine of the 54 patients or convalescents tested for leptospirosis were seropositive. Two cases showed a confirmed infection for both plague and leptospirosis. While evidence supports the plague nature of this outbreak, the results suggest that some of the suspected plague cases might be due to leptospirosis. In any case, this diagnosis will have to be evoked in the future if a similar outbreak occurs in this region of Africa.

Circumventing Y. pestis Virulence by Early Recruitment of Neutrophils to the Lungs during Pneumonic Plague.

Directory of Open Access Journals (Sweden)

Yaron Vagima

2015-05-01

Full Text Available Pneumonic plague is a fatal disease caused by Yersinia pestis that is associated with a delayed immune response in the lungs. Because neutrophils are the first immune cells recruited to sites of infection, we investigated the mechanisms responsible for their delayed homing to the lung. During the first 24 hr after pulmonary infection with a fully virulent Y. pestis strain, no significant changes were observed in the lungs in the levels of neutrophils infiltrate, expression of adhesion molecules, or the expression of the major neutrophil chemoattractants keratinocyte cell-derived chemokine (KC, macrophage inflammatory protein 2 (MIP-2 and granulocyte colony stimulating factor (G-CSF. In contrast, early induction of chemokines, rapid neutrophil infiltration and a reduced bacterial burden were observed in the lungs of mice infected with an avirulent Y. pestis strain. In vitro infection of lung-derived cell-lines with a YopJ mutant revealed the involvement of YopJ in the inhibition of chemoattractants expression. However, the recruitment of neutrophils to the lungs of mice infected with the mutant was still delayed and associated with rapid bacterial propagation and mortality. Interestingly, whereas KC, MIP-2 and G-CSF mRNA levels in the lungs were up-regulated early after infection with the mutant, their protein levels remained constant, suggesting that Y. pestis may employ additional mechanisms to suppress early chemoattractants induction in the lung. It therefore seems that prevention of the early influx of neutrophils to the lungs is of major importance for Y. pestis virulence. Indeed, pulmonary instillation of KC and MIP-2 to G-CSF-treated mice infected with Y. pestis led to rapid homing of neutrophils to the lung followed by a reduction in bacterial counts at 24 hr post-infection and improved survival rates. These observations shed new light on the virulence mechanisms of Y. pestis during pneumonic plague, and have implications for the

Coregulation of host-adapted metabolism and virulence by pathogenic yersiniae

Directory of Open Access Journals (Sweden)

Ann Kathrin eHeroven

2014-10-01

Full Text Available Deciphering the principles how pathogenic bacteria adapt their metabolism to a specific host microenvironment is critical for understanding bacterial pathogenesis. The enteric pathogenic Yersinia species Y. pseudotuberculosis and Y. enterocolitica and the causative agent of plague, Y. pestis, are able to survive in a large variety of environmental reservoirs (e.g. soil, plants, insects as well as warm-blooded animals (e.g. rodents, pigs, humans with a particular preference for lymphatic tissues. In order to manage rapidly changing environmental conditions and inter-bacterial competition, Yersinia senses the nutritional composition during the course of an infection by special molecular devices, integrates this information and adapts its metabolism accordingly. In addition, nutrient availability has an impact on expression of virulence genes in response to C-sources, demonstrating a tight link between the pathogenicity of yersiniae and utilization of nutrients. Recent studies revealed that global regulatory factors such as the cAMP receptor protein (Crp and the carbon storage regulator (Csr system are part of a large network of transcriptional and posttranscriptional control strategies adjusting metabolic changes and virulence in response to temperature, ion and nutrient availability. Gained knowledge about the specific metabolic requirements and the correlation between metabolic and virulence gene expression that enable efficient host colonization led to the identification of new potential antimicrobial targets.

Controlling Ebola: what we can learn from China's 1911 battle against the pneumonic plague in Manchuria

Directory of Open Access Journals (Sweden)

He Liu

2015-04-01

Full Text Available The pneumonic plague, which spread across Northeast China during the winter of 1910 and spring of 1911, caused numerous deaths and brought about severe social turmoil. After compulsory quarantine and other epidemic prevention measures were enforced by Dr Wu Lien-teh, the epidemic was brought to an end within 4 months. This article reviews the ways in which the plague was dealt with from a historical perspective, based on factors such as clinical manifestations, duration of illness, case fatality rate, degree of transmissibility, poverty, inadequate healthcare infrastructure, and the region's recent strife-filled history. Similarities were sought between the pneumonic plague in Northeast China in the twentieth century and the Ebola virus outbreak that is currently ravaging Africa, and an effort made to summarize the ways in which specific measures were applied successfully to fight the earlier epidemic. Our efforts highlight valuable experiences that are of potential benefit in helping to fight the current rampant Ebola epidemic in West Africa.

HERITABILITY AND RESPONSE TO SELECTION FOR GROWTH IN THE F1 GENERATION OF CRAYFISH Procambarus acanthophorus

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Carlos Perez Rostro

2012-11-01

Full Text Available The crayfish Procambarus (A. acanthophorus is a crustacean relevant for regional fisheries in Veracruz, Mexico, with ideal aquaculture characteristics, except for its small size. Thus, a study was conducted with the aim to evaluate the response to selection in the first generation (F1 and heritability (h2 of the crayfish. A group of 2135 organisms with average weight (±S.D. 4.1 ± 1.79 g were captured from the wild (G0, and 10 % (i = 1,755 of the population was selected with the highest body weight by gender: 140 females (5.62 ± 1.97 g and 48 males (6.02 ± 1.9 g, forming the progenitors of the selection line (LS. The control line (LC was formed from a batch obtained at random. Thirty full-sib families were obtained per line (F1, and cultured individually for five months in a recirculation system with mechanical and biological filtration under laboratory conditions and supplied with food twice a day (Camaronina 35 % protein. Monthly heritability (h2 in broad sense was estimated using a full-sib design, based on the components of variance (ANOVA REML method and the growth was compared between lines in the F1. The mean h2's for weight after five months of culture were 0.27±0.11 for LC and 0.34±0.12 for LS, being the LS in F1 9.6 % heavier than the LC, with 84 and 88 % survival at the end of the study. It is possible to implement a breeding program based on selection for species growth.

[All around the deathbed of Lubbert ten Busch. The Modern Devotion and the plague in Deventer in 1398].

Science.gov (United States)

Mertens, T

1999-01-01

The seriousness of plague epidemics can be expressed in numbers and medical terms, but we get closer to the past, and it becomes our own history more than in any other way, when we can empathise with the story of a single individual. In the summer months of 1398, the plague raged in the city of Deventer, which lies on the river IJssel, in the east of the present-day Netherlands. This plague epidemic also threatened the small community of priests and minor clerics which gave rise to the new spiritual movement of the Modern Devotion. This new community was concerned about its survival. Their vocation required that the brethren should help the citizens who remained behind. However, this could prove to be their undoing, and therefore it would be better to leave the city. They resolved the dilemma by dividing into two groups. Half of the brethren left to ensure the continuity of the community; the other half stayed in Deventer to help the people. The two groups stayed in contact by means of letters, the text of which has survived in several sources. The fears and forebodings became reality. The plague also affected the new community of brethren. The deputy rector, Lubbert ten Busch, also died of the plague. There is a letter from him which he wrote just before he died. This farewell letter was sent together with a letter from one of the brethren, saying that Lubbert had meanwhile died, and describing the scene of his death. Because of the personal tone and the tragic of content, the letters about the death of Lubbert ten Busch are unique medieval documents. They give a good insight into the way in which the plague could personally affect someone and his immediate companions in the late Middle Ages. This paper focuses attention on these letters, and reconstructs the events around this death, so that the letters speak to us once again.

Supplementation of Carrot (Daucus carrota as Natural Source of Beta-carotene prepared by Several Methods in Feed to Increase Blue Colour of Freshwater Crayfish Red Claw (Cherax quadricarinatus

Directory of Open Access Journals (Sweden)

Woro H. Satyantini

2012-02-01

Full Text Available Red claw (Cherax quadricarinatus is one kind of freshwater crayfish that can cultured as consumption or ornamental fish commodities.  The colour of body was important character for performance of red claw as ornamental fish commodity.  Red claw with blue body colour is more expensive than brown.  The purpose of  this experiment was to know the influence addition of carrot with several methods in feed on blue colour  of freshwater crayfish red claw and which was the best preparation method to increase blue colour of freshwater crayfish red claw. The experiment used Completely Randomized Design with four treatments: A (control, B (extract, C (juice and D (shreeded of carrot with 45 ppm dose and five time replicates.  Data was analysed with Kruskal-Wallis and continued with Z test. Result of the experiment was showed that addition of carrot as natural source of beta-carotene with several preparation in feed increase significantly (P Keywords: freshwater crayfish, colour of red claw, carrot, beta-carotene   ABSTRAK Red claw (Cherax quadricarinatus adalah salah satu jenis lobster air tawar yang dapat dibudidayakan sebagai komoditas konsumsi maupun hias.  Sebagai komoditas ikan hias, warna tubuh merupakan karakter penting untuk menunjang penampilan red claw.  Red claw ukuran konsumsi yang memiliki warna biru akan memiliki nilai jual yang lebih tinggi daripada red claw berwarna coklat.  Tujuan penelitian ini untuk mengetahui pengaruh penambahan wortel sebagai sumber beta karoten alami dengan beberapa metoda pengolahan pada pakan terhadap peningkatan warna biru lobster red claw. Penelitian menggunakan Rancangan Acak Lengkap dengan 4 perlakuan : A (kontrol, B (ekstrak, C (jus dan D (serutan wortel dengan menggunakan dosis 45 ppm beta karoten dan ulangan 5 kali.  Data dianalisis dengan uji Kruskal-Wallis dan dilanjutkan dengan uji Z.  Hasil penelitian menunjukkan bahwa penambahan wortel sebagai sumber beta karoten alami dengan beberapa metode

FLEAS OF BLACK-FOOTED FERRETS (MUSTELA NIGRIPES) AND THEIR POTENTIAL ROLE IN THE MOVEMENT OF PLAGUE.

Science.gov (United States)

Mize, Erica L; Grassel, Shaun M; Britten, Hugh B

2017-07-01

Sylvatic plague is one of the major impediments to the recovery of the black-footed ferret ( Mustela nigripes ) because it decimates their primary prey species, prairie dogs ( Cynomys spp.), and directly causes mortality in ferrets. Fleas are the primary vector of Yersinia pestis , the causative agent of sylvatic plague. The goal of this research was to better understand the flea fauna of ferrets and the factors that might influence flea abundance on ferrets. Fleas from ferrets were tested for Y. pestis in a post hoc assessment to investigate the plausibility that some ferrets could act as incidental transporter hosts of fleas infected with Y. pestis . Fleas were collected from ferrets captured on the Lower Brule Indian Reservation in central South Dakota, US from 2009 to 2012. A total of 528 fleas collected from 67 individual ferrets were identified and tested for the presence of Y. pestis with a nested PCR assay. The predominant flea recovered from ferrets was Oropsylla hirsuta , a species that comprises 70-100% of the fleas recovered from prairie dogs and their burrows in the study area. Yersinia pestis was detected at low levels in fleas collected from ferrets with prevalence ranging from 0% to 2.9%; male ferrets harbored significantly more fleas than female ferrets. Six of 67 ferrets vaccinated against plague carried fleas that tested positive for Y. pestis , which suggests ferrets vaccinated against plague could inadvertently act as incidental transporter hosts of Y. pestis -positive fleas.

Discovery of a Leptospirosis Cluster Amidst a Pneumonic Plague Outbreak in a Miners’ Camp in the Democratic Republic of the Congo

Science.gov (United States)

Bertherat, Eric; Mueller, Melissa J.; Shako, Jean-Christophe; Picardeau, Mathieu

2014-01-01

Conditions in the Democratic Republic of the Congo provide an ideal environment for leptospirosis and plague, both of which can cause severe pulmonary manifestations. In December 2004, an outbreak of lethal pneumonia occurred in a local mining camp, affecting 130 persons and killing 57 of them. Clinical signs, fast disease spread, and initial laboratory investigations suggested pneumonic plague. While leptospirosis had not recently been described in the region, it was considered as a differential diagnosis. Anti-Leptospira antibodies were detected by microscopic agglutination test (MAT). A confirmed case of leptospirosis was defined as having consistent clinical signs and any one of the following: seroconversion or four-fold increase in MAT titre for paired serum samples, or a MAT titre ≥ 1:400 for acute-phase serum samples. Twenty-nine of the 54 patients or convalescents tested for leptospirosis were seropositive. Two cases showed a confirmed infection for both plague and leptospirosis. While evidence supports the plague nature of this outbreak, the results suggest that some of the suspected plague cases might be due to leptospirosis. In any case, this diagnosis will have to be evoked in the future if a similar outbreak occurs in this region of Africa. PMID:24514425

The plague under Marcus Aurelius and the decline and fall of the Roman Empire.

Science.gov (United States)

Fears, J Rufus

2004-03-01

The Roman Empire of the second century was a superpower that, in relative terms, dominated its world as much as the United States does today. In 166 AD, a plague broke out od pandemic proportions. The pandemic ravaged the entire extent of the Roman Empire, from its eastern frontiers in Iraq to its western frontiers on the Rhine River and Gaul, modern France, and western Germany. The disease is identified most often as smallpox, but it may have been anthrax. The study of bacterial DNA may enable identification of this plague that ravaged the Roman Empire at recurrent intervals for more than 100 years and that had a significant role in the decline and fall of this great superpower.

Lessons from the History of Quarantine, from Plague to Influenza A

Centers for Disease Control (CDC) Podcasts

2013-05-08

Reginald Tucker reads an abridged version of the Emerging Infectious Diseases’ Historical Review, Lessons from the History of Quarantine, from Plague to Influenza A.  Created: 5/8/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 5/15/2013.

Contribution of land use to rodent flea load distribution in the plague endemic area of Lushoto District, Tanzania.

Science.gov (United States)

Hieronimo, Proches; Kihupi, Nganga I; Kimaro, Didas N; Gulinck, Hubert; Mulungu, Loth S; Msanya, Balthazar M; Leirs, Herwig; Deckers, Jozef A

2014-07-01

Fleas associated with different rodent species are considered as the major vectors of bubonic plague, which is still rampant in different parts of the world. The objective of this study was to investigate the contribution of land use to rodent flea load distribution at fine scale in the plague endemic area of north-eastern Tanzania. Data was collected in three case areas namely, Shume, Lukozi and Mwangoi, differing in plague incidence levels. Data collection was carried out during both wet and dry seasons of 2012. Analysis of Variance and Boosted Regression Tree (BRT) statistical methods were used to clarify the relationships between fleas and specific land use characteristics. There was a significant variation (P ≤ 0.05) of flea indices in different land use types. Fallow and natural forest had higher flea indices whereas plantation forest mono-crop and mixed annual crops had the lowest flea indices among the aggregated land use types. The influence of individual land use types on flea indices was variable with fallow having a positive effect and land tillage showing a negative effect. The results also demonstrated a seasonal effect, part of which can be attributed to different land use practices such as application of pesticides, or the presence of grass strips around fields. These findings suggest that land use factors have a major influence on rodent flea abundance which can be taken as a proxy for plague infection risk. The results further point to the need for a comprehensive package that includes land tillage and crop type considerations on one hand and the associated human activities on the other, in planning and implementation of plague control interventions.

A recombinant raccoon poxvirus vaccine expressing both Yersinia pestis F1 and truncated V antigens protects animals against lethal plague.

Science.gov (United States)

Rocke, Tonie E.; Kingstad-Bakke, B; Berlier, W; Osorio, J.E.

2014-01-01

In previous studies, we demonstrated in mice and prairie dogs that simultaneous administration of two recombinant raccoon poxviruses (rRCN) expressing Yersinia pestis antigens (F1 and V307-a truncated version of the V protein) provided superior protection against plague challenge compared to individual single antigen constructs. To reduce costs of vaccine production and facilitate implementation of a sylvatic plague vaccine (SPV) control program for prairie dogs, a dual antigen construct is more desirable. Here we report the construction and characterization of a novel RCN-vectored vaccine that simultaneously expresses both F1 and V307 antigens. This dual antigen vaccine provided similar levels of protection against plague in both mice and prairie dogs as compared to simultaneous administration of the two single antigen constructs and was also shown to protect mice against an F1 negative strain of Y. pestis.. The equivalent safety, immunogenicity and efficacy profile of the dual RCN-F1/V307 construct warrants further evaluation in field efficacy studies in sylvatic plague endemic areas.

Calcium transport mechanism in molting crayfish revealed by microanalysis

International Nuclear Information System (INIS)

Mizuhira, V.; Ueno, M.

1983-01-01

Crayfish provide a good model in which to study the transport mechanism of Ca ions. During the molting stage, decalcified Ca ions are transferred into the blood and accumulate in the gastrolith epithelium, after which a gastrolith is formed on the surface of the epithelium. The gastrolith is dissolved in the stomach after molting, and the Ca is reabsorbed and redistributed throughout the newly formed exoskeleton. We studied the mechanism of Ca transport by cytochemical precipitation of Ca ions and by electron microanalysis, including X-ray microanalysis (EDX) and electron energy-loss spectroscopy (EELS), with a computer. In EDX analysis, the fine precipitates of K-antimonate in the gastrolith mitochondria clearly defined Ca with antimony; we also observed a large amount of Ca-oxalate in the mitochondria, and Ca-K X-ray pulses were clearly defined. Ca-K X-rays were also detected from fresh freeze-substituted mitochondria. Finally, we succeeded in taking a Ca-L EELS image from the mitochondria of fresh freeze-substituted thin sections. Only a very small amount of Ca was detected from the cell membrane and other organelles. Ca-adenosine triphosphatase (ATPase) and Mg-ATPase activity was also very clearly demonstrated in the mitochondria. These enzymes may play an important role in Ca metabolism

A Personal View of How Paleomicrobiology Aids Our Understanding of the Role of Lice in Plague Pandemics.

Science.gov (United States)

Raoult, Didier

2016-08-01

We have been involved in the field of paleomicrobiology since 1998, when we used dental pulp to identify Yersinia pestis as the causative agent of the great plague of Marseille (1720). We recently designed a specific technique, "suicide PCR," that can prevent contamination. A controversy arose between two teams, with one claiming that DNA must be altered to amplify it and the other group claiming that demographic data did not support the role of Y. pestis in the Black Death (i.e., the great plague of the Middle Ages). These controversies led us to evaluate other epidemiological models and to propose the body louse as the vector of this pandemic. This proposal was substantiated by experimental models, the recovery of Y. pestis from lice in the Congo, and the identification of epidemics involving both Y. pestis and Bartonella quintana (the agent of trench fever, transmitted by the body louse) in ancient corpses from mass graves. Paleomicrobiology has led to a re-evaluation of plague pandemics.

Isolation of crustecdysone (20R-hydroxyecdysone) from a crayfish (Jasus lalandei H. Milne-Edwards)

Science.gov (United States)

Horn, D. H. S.; Fabbri, S.; Hampshire, F.; Lowe, M. E.

1968-01-01

1. A small amount (2mg.) of crustecdysone, a moulting hormone of crustaceans, was isolated from 1 ton of crayfish waste. 2. The purification procedure used was developed with the aid of crustacean and insect bioassays. 3. CM-Sephadex was found to be superior to Sephadex and very effective for the chromatographic separation of crustecdysone from other non-ionic compounds. The higher efficiency of CM-Sephadex is attributed to the greater number of carboxyl groups available for hydrogen-bonding. 4. Reversed-phase chromatography, with butan-1-ol–cyclohexane mixtures as the stationary phase and water as the flowing phase, proved superior to countercurrent distribution with these solvents for the fractionation of purified extracts. 5. A second moulting hormone, deoxycrustecdysone, and the red-concentrating hormone were obtained in a partially purified form. PMID:5685865

Field and laboratory tests on acute toxicity of cadmium to freshwater crayfish

Energy Technology Data Exchange (ETDEWEB)

1986-09-01

Environmental regulatory standards for cadmium (EPA 1980), like those for most pollutants, are based on acute, laboratory toxicity tests of single species. Such tests can be conducted rapidly and inexpensively in comparison to acute or chronic field studies, but their validity has often been questioned. Laboratory-based criteria are subject to two criticisms: (1) chemical and physical conditions differ greatly in degree and variability from laboratory to field, and (2) species are not isolated, but live in an ecosystem of interacting taxa and biofeedback. To investigate the validity of basing field toxicity standards on laboratory data, the authors subjected the freshwater crayfish Orconectes immunis for 96 h to various levels of cadmium in laboratory aquaria and experimental ponds. The study was designed to evaluate in part the first criticism of lab-based criteria. The studies were conducted concurrently with similar short-term experiments on the fathead minnow, Pimephales promelas, and coincided with studies of chronic cadmium stress on fathead minnows in experimental ponds.

Epidemiology of Human Plague in the United States, 1900–2012

Centers for Disease Control (CDC) Podcasts

2015-02-23

Dr. Kiersten Kugeler discusses the Epidemiology of Human Plague in the United States.  Created: 2/23/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/23/2015.

Mutated and Bacteriophage T4 Nanoparticle Arrayed F1-V Immunogens from Yersinia pestis as Next Generation Plague Vaccines

Science.gov (United States)

Tao, Pan; Mahalingam, Marthandan; Kirtley, Michelle L.; van Lier, Christina J.; Sha, Jian; Yeager, Linsey A.; Chopra, Ashok K.; Rao, Venigalla B.

2013-01-01

Pneumonic plague is a highly virulent infectious disease with 100% mortality rate, and its causative organism Yersinia pestis poses a serious threat for deliberate use as a bioterror agent. Currently, there is no FDA approved vaccine against plague. The polymeric bacterial capsular protein F1, a key component of the currently tested bivalent subunit vaccine consisting, in addition, of low calcium response V antigen, has high propensity to aggregate, thus affecting its purification and vaccine efficacy. We used two basic approaches, structure-based immunogen design and phage T4 nanoparticle delivery, to construct new plague vaccines that provided complete protection against pneumonic plague. The NH2-terminal β-strand of F1 was transplanted to the COOH-terminus and the sequence flanking the β-strand was duplicated to eliminate polymerization but to retain the T cell epitopes. The mutated F1 was fused to the V antigen, a key virulence factor that forms the tip of the type three secretion system (T3SS). The F1mut-V protein showed a dramatic switch in solubility, producing a completely soluble monomer. The F1mut-V was then arrayed on phage T4 nanoparticle via the small outer capsid protein, Soc. The F1mut-V monomer was robustly immunogenic and the T4-decorated F1mut-V without any adjuvant induced balanced TH1 and TH2 responses in mice. Inclusion of an oligomerization-deficient YscF, another component of the T3SS, showed a slight enhancement in the potency of F1-V vaccine, while deletion of the putative immunomodulatory sequence of the V antigen did not improve the vaccine efficacy. Both the soluble (purified F1mut-V mixed with alhydrogel) and T4 decorated F1mut-V (no adjuvant) provided 100% protection to mice and rats against pneumonic plague evoked by high doses of Y. pestis CO92. These novel platforms might lead to efficacious and easily manufacturable next generation plague vaccines. PMID:23853602

Mutated and bacteriophage T4 nanoparticle arrayed F1-V immunogens from Yersinia pestis as next generation plague vaccines.

Directory of Open Access Journals (Sweden)

Pan Tao

Full Text Available Pneumonic plague is a highly virulent infectious disease with 100% mortality rate, and its causative organism Yersinia pestis poses a serious threat for deliberate use as a bioterror agent. Currently, there is no FDA approved vaccine against plague. The polymeric bacterial capsular protein F1, a key component of the currently tested bivalent subunit vaccine consisting, in addition, of low calcium response V antigen, has high propensity to aggregate, thus affecting its purification and vaccine efficacy. We used two basic approaches, structure-based immunogen design and phage T4 nanoparticle delivery, to construct new plague vaccines that provided complete protection against pneumonic plague. The NH₂-terminal β-strand of F1 was transplanted to the COOH-terminus and the sequence flanking the β-strand was duplicated to eliminate polymerization but to retain the T cell epitopes. The mutated F1 was fused to the V antigen, a key virulence factor that forms the tip of the type three secretion system (T3SS. The F1mut-V protein showed a dramatic switch in solubility, producing a completely soluble monomer. The F1mut-V was then arrayed on phage T4 nanoparticle via the small outer capsid protein, Soc. The F1mut-V monomer was robustly immunogenic and the T4-decorated F1mut-V without any adjuvant induced balanced TH1 and TH2 responses in mice. Inclusion of an oligomerization-deficient YscF, another component of the T3SS, showed a slight enhancement in the potency of F1-V vaccine, while deletion of the putative immunomodulatory sequence of the V antigen did not improve the vaccine efficacy. Both the soluble (purified F1mut-V mixed with alhydrogel and T4 decorated F1mut-V (no adjuvant provided 100% protection to mice and rats against pneumonic plague evoked by high doses of Y. pestis CO92. These novel platforms might lead to efficacious and easily manufacturable next generation plague vaccines.

Evaluation of systemic insecticides mixed in rodenticide baits for plague vector control

DEFF Research Database (Denmark)

Larsen, Kim Søholt; Lodal, Jens

1997-01-01

Rodenticide baits containing systemic insecticides were evaluated in the laboratory for their palatability to the house rat Rattus rattus and for their toxicity against the oriental rat flea Xenopsylla cheopis - both animals are important Vectors of plague in Africa. The test bait and a non...

Remote sensing for landscape epidemiology : spatial analysis of plague hosts in Kazakhstan

NARCIS (Netherlands)

Wilschut, L.I.

2015-01-01

The spatial distribution of hosts is a crucial aspect for the understanding of infectious disease dynamics. In Kazakhstan, the great gerbil (Rhombomys opimus) is the main host for plague (Yersinia pestis infection) and poses a public health threat, yet their spatial distribution is unknown. Great

The dancing plague: a public health conundrum.

Science.gov (United States)

Donaldson, L J; Cavanagh, J; Rankin, J

1997-07-01

The phenomenon of mass, frenzied dancing affected large populations in various parts of Europe from the thirteenth century and lasted, on and off, for three centuries. The exact aetiology of the Dancing Plague (or Dancing Mania) is still unclear. Retrospective historical review of this public health problem reveals claims for causative factors including demonic possession, epilepsy, the bite of a tarantula, ergot poisoning and social adversity. It seems unlikely that Dancing Mania resulted from a single cause but rather resulted from multiple factors combining with a predisposing cultural background and triggered by adverse social circumstances. Dancing Mania remains one of the unresolved mysteries of public health.

Combinational deletion of three membrane protein-encoding genes highly attenuates yersinia pestis while retaining immunogenicity in a mouse model of pneumonic plague.

Science.gov (United States)

Tiner, Bethany L; Sha, Jian; Kirtley, Michelle L; Erova, Tatiana E; Popov, Vsevolod L; Baze, Wallace B; van Lier, Christina J; Ponnusamy, Duraisamy; Andersson, Jourdan A; Motin, Vladimir L; Chauhan, Sadhana; Chopra, Ashok K

2015-04-01

Previously, we showed that deletion of genes encoding Braun lipoprotein (Lpp) and MsbB attenuated Yersinia pestis CO92 in mouse and rat models of bubonic and pneumonic plague. While Lpp activates Toll-like receptor 2, the MsbB acyltransferase modifies lipopolysaccharide. Here, we deleted the ail gene (encoding the attachment-invasion locus) from wild-type (WT) strain CO92 or its lpp single and Δlpp ΔmsbB double mutants. While the Δail single mutant was minimally attenuated compared to the WT bacterium in a mouse model of pneumonic plague, the Δlpp Δail double mutant and the Δlpp ΔmsbB Δail triple mutant were increasingly attenuated, with the latter being unable to kill mice at a 50% lethal dose (LD50) equivalent to 6,800 LD50s of WT CO92. The mutant-infected animals developed balanced TH1- and TH2-based immune responses based on antibody isotyping. The triple mutant was cleared from mouse organs rapidly, with concurrent decreases in the production of various cytokines and histopathological lesions. When surviving animals infected with increasing doses of the triple mutant were subsequently challenged on day 24 with the bioluminescent WT CO92 strain (20 to 28 LD50s), 40 to 70% of the mice survived, with efficient clearing of the invading pathogen, as visualized in real time by in vivo imaging. The rapid clearance of the triple mutant, compared to that of WT CO92, from animals was related to the decreased adherence and invasion of human-derived HeLa and A549 alveolar epithelial cells and to its inability to survive intracellularly in these cells as well as in MH-S murine alveolar and primary human macrophages. An early burst of cytokine production in macrophages elicited by the triple mutant compared to WT CO92 and the mutant's sensitivity to the bactericidal effect of human serum would further augment bacterial clearance. Together, deletion of the ail gene from the Δlpp ΔmsbB double mutant severely attenuated Y. pestis CO92 to evoke pneumonic plague in a

Recent results on the spatiotemporal modelling and comparative analysis of Black Death and bubonic plague epidemics

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