Allen Julie M
Full Text Available Abstract Background Sucking lice (Phthiraptera: Anoplura are obligate, permanent ectoparasites of eutherian mammals, parasitizing members of 12 of the 29 recognized mammalian orders and approximately 20% of all mammalian species. These host specific, blood-sucking insects are morphologically adapted for life on mammals: they are wingless, dorso-ventrally flattened, possess tibio-tarsal claws for clinging to host hair, and have piercing mouthparts for feeding. Although there are more than 540 described species of Anoplura and despite the potential economical and medical implications of sucking louse infestations, this study represents the first attempt to examine higher-level anopluran relationships using molecular data. In this study, we use molecular data to reconstruct the evolutionary history of 65 sucking louse taxa with phylogenetic analyses and compare the results to findings based on morphological data. We also estimate divergence times among anopluran taxa and compare our results to host (mammal relationships. Results This study represents the first phylogenetic hypothesis of sucking louse relationships using molecular data and we find significant conflict between phylogenies constructed using molecular and morphological data. We also find that multiple families and genera of sucking lice are not monophyletic and that extensive taxonomic revision will be necessary for this group. Based on our divergence dating analyses, sucking lice diversified in the late Cretaceous, approximately 77 Ma, and soon after the Cretaceous-Paleogene boundary (ca. 65 Ma these lice proliferated rapidly to parasitize multiple mammalian orders and families. Conclusions The diversification time of sucking lice approximately 77 Ma is in agreement with mammalian evolutionary history: all modern mammal orders are hypothesized to have diverged by 75 Ma thus providing suitable habitat for the colonization and radiation of sucking lice. Despite the concordant timing of
Hypša, Václav; Křížek, J.
Roč. 54, č. 2 (2007), s. 242-251. ISSN 0095-3628 Grant ostatní: GA ČR(CZ) GA206/04/0520 Institutional research plan: CEZ:AV0Z60220518 Keywords : Anoplura * endosymbionts * coevolution * molecular phylogeny Subject RIV: EE - Microbiology, Virology Impact factor: 2.558, year: 2007
Renfu Shao; Barker, Stephen C.; Hu Li; Simon Song; Shreekanta Poudel; Yuan Su
Parasitic lice (order Phthiraptera) infest birds and mammals. The typical animal mitochondrial (mt) genome organization, which consists of a single chromosome with 37 genes, was found in chewing lice in the suborders Amblycera and Ischnocera. The sucking lice (suborder Anoplura) known, however, have fragmented mt genomes with 9–20 minichromosomes. We sequenced the mt genome of the elephant louse, Haematomyzus elephantis – the first species of chewing lice investigated from the suborder Rhynch...
Pakeer, O; Jeffery, J; Mohamed, A M; Ahmad, F; Baharudin, O
Four cases of pediculosis, two in adults and two in children, caused by the crab-louse, Pthirus pubis Linnaeus, 1758 (Diptera: Anoplura) is reported from peninsular Malaysia. This is the second report of the problem to be documented from the country. Although P. pubis is closely associated with genital hairs, it is, however, also found to occur on the eyelashes, eyebrows, hairs of the body, head and axilla. The few reported cases of pthiriasis probably do not reflect the true situation. PMID:18209717
Leonardi, María Soledad; Crespo, Enrique A; Raga, Juan Antonio; Fernández, Mercedes
The members of the Family Echinophthiriidae (Phthiraptera: Anoplura) are unique among insects because they infest hosts with an amphibious lifestyle. During their evolution they developed morphological traits that are reflected in unique features. The SEM is a helpful tool to analyze them. Knowing in detail the external structure of these lice is the first step to understand the whole process that derived from the co-adaptation of lice and pinnipeds to the marine environment. For the first time, we studied the external structure of all stages of an echinophthiriid louse. The results are discussed in the light of their evolutionary, functional, and ecological implications. PMID:22503484
Dong, Wen-Ge; Song, Simon; Guo, Xian-Guo; Jin, Dao-Chao; Yang, Qianqian; Barker, Stephen C.; Shao, Renfu
Background The suborder Anoplura contains 540 species of blood-sucking lice that parasitize over 840 species of eutherian mammals. Fragmented mitochondrial (mt) genomes have been found in the lice of humans, pigs, horses and rats from four families: Pediculidae, Pthiridae, Haematopinidae and Polyplacidae. These lice, eight species in total, are from the same major clade of the Anoplura. The mt genomes of these lice consist of 9–20 minichromosomes; each minichromosome is 1.5–4 kb in size and h...
Gutiérrez, María Mercedes; Werdin-González, Jorge Omar; Stefanazzi, Natalia; Bras, Cristina; Ferrero, Adriana Alicia
The human head louse, Pediculus humanus capitis (Anoplura: Pediculidae), is an ectoparasite confined to the scalp and human hairs. The repeated use of insecticides for the control of head lice during past decades has resulted in the development of marked levels of resistance. Natural compounds such as essential oils (EOs) have been suggested as alternative sources for insect control agents. In order to introduce a new pediculicide based on EOs, the effectiveness of the product and their effects on human being must be analyzed. In consequence, the biological activity of EOs from the leaves and fruits of Schinus areira (Anacardiaceae) and the leaves of Thymus vulgaris (Lamiaceae), Aloysia polystachya and Aloysia citriodora (Verbenacea) were evaluated against the eggs and adults of P. humanus capitis by fumigant and contact toxicity bioassays. Additionally, dermal corrosion/irritation tests were performed on New Zealand albino rabbits. In a fumigant bioassay, EOs from the leaves and fruits of S. areira were the most toxic against P. humanus capitis adults while these EOs and T. vulgaris were the most effective against the eggs. In contact bioassay, the EO from T. vulgaris was the most toxic against both stages. In the corrosion/irritation tests, the EOs did not produce dermal effects. According to the results, the essential oils from the leaves of T. vulgaris would be a valid tool for the management of P. humanus capitis. This EO produces a high knockdown effect in adults (followed by mortality) and toxicity in the eggs when it is applied for 21 min at a low concentration. PMID:26462802
Dolores del Carmen Castro
Full Text Available The ultrastructure of Proechinophthirus zumpti Werneck, 1955, mainly the external chorionic features of the egg, is described through electronic microscopy techniques. This species was first cited in Argentina, infesting Arctocephalus australis (Zimmermann, 1873. The morphological adaptations of adults and nymphs are described in both species of Proechinophthirus parasitic on Otariidae: P. fluctus (Ferris, 1916 and P. zumpti.
González Audino, P; Barrios, S; Vassena, C; Mougabure Cueto, G; Zerba, E; Picollo, M I
We studied the profile of permethrin resistance in populations of head lice infesting children 6-12 yr old in schools and their homes in and around Buenos Aires, Argentina. Five permethrin-resistant populations with different levels of resistance were collected: Hogar Loyola (HL), Republica de Turquia (RT), Hogar Mitre (HM), Guardia de Honor (GH), and Ricardo Guiraldes (RG). One susceptible population, Bandera Argentina (BA), also was collected. Their level of resistance was evaluated, and results showed resistance ratios of 13 for HL, 16 for RT, 22 for HM, 61 for GH, and 69 for RG. To elucidate the possible involvement of the cytochrome P450 monooxygenase system in conferring permethrin resistance, ethoxycoumarin-O-deethylase (ECOD) activity was measured in abdomens of individual third instars and adults by using a fluorometric assay. The ECOD activity was lower in the susceptible BA population (4.7 ng per louse) than in the resistant ones (13.7 ng per louse for RG, 12.3 ng per louse for GH, 8.6 ng per louse for RT, and 8.2 ng per louse for HL). ECOD activity was significantly correlated with the level of resistance in the field populations (r = 0.97, P = 0.0009), suggesting a role for cytochrome monooxygenase P450 system in permethrin resistance by head louse, Pediculus humanus capitis De Geer. PMID:15962785
Dik, Bilal; Uslu, Ugur
This study was carried out in order to determine the prevalence of lice on hares (Lepus europaeus L.) in the Konya province of Turkey from October 2003 to January 2007. During this period, 54 hares were examined for lice, 5 of them (11%) were found to be infested with lice and a total of 41 lice specimens were collected from the infested hares. Two species; Haemodipsus lyriocephalus (Burmeister, 1839) and H. setoni Ewing, 1924 were identified and H. lyriocephalus was more abundant than H. setoni. PMID:18645947
Chaĭka, S Iu
The ultrastructure of the Malpighian tubes in human louse Pediculus humanus corporis has been studied. The cells of the Malpighian tubules have the uniform structure: the apical surface is covered with microvilli, the basal plasmatic membrana forms relatively small invaginations. The microvilli are most developed in cells of the proximal department of the Malpighian tubules. Microvilli of the apical surface of the cells do not contain mitochondria which are localized mainly in supranuclear part of the cell. Cells are lined with a homogenous basal membrane. PMID:3986247
Pedro Marcos Linardi
Full Text Available Adultos, ninfas e lêndeas da espécie Pediculus humanus foram encontrados em barraco, infestando roupas de cama e vestes de três habitantes em uma favela na cidade de São Paulo, Estado de São Paulo, Brasil. Lêndeas, num total de 198, foram encontradas aderidas em 15,0 cm² de fibras de vestes infestadas, dando uma média de 13,2 por cm². Dada a freqüência em diversas cidades do Brasil, de precárias condições de vida, promiscuidade, ausência de saneamento básico e negligência das autoridades sanitárias tal ocorrência poderá ser maior do que um simples caso isolado.Adults, nymphs and nits of the Pediculus humanus were found in a frame-house infesting the clothes and bedding of three inhabitants in a shanty town in S. Paulo county, S. Paulo State. A total of 198 nits were found glued in 15.0 cm² of fibres of the infested clothing, giving a ratio of 13.2 nits/cm². Having in view that the precarious living conditions, promiscuity, absence of basic sanitation and negligence of the sanitary authorities in various Brazilian cities, this situation should not be underestimated. This find should be more frequent than an isolated observation.
Khan, M. A.; Schaalje, G. B.
Two groups (A and C) of range cows were treated in February with chlorpyrifos (16 mL Dursban 44/cow) for the control of heavy infestations of the short-nosed cattle louse. Group A was treated in 1977 and group C in 1979 and each treated group was compared with a separate untreated group. Some of the treated cows were identified as carriers of louse infestation (subgroups A1 and C1), while others were noncarriers (subgroups A2 and C2). The maximum level of reduction in louse populations was 99...
Choi, Han-Young; Yang, Young-Cheol; Lee, Si Hyeock; Clark, J Marshall; Ahn, Young-Joon
The control efficacy of clove, Eugenia caryophyllata, and eucalyptus, Eucalyptus globulus, essential oils and 15 formulations containing these essential oils alone (8, 12, and 15% sprays) and their binary mixtures (7:3, 5:5, and 3:7 by weight) against adult females of insecticide-susceptible KR-HL and dual malathion- and permethrin-resistant BR-HL strains of head louse, Pediculus humanus capitis (De Geer), was examined by using contact plus fumigant and human hair wig (placed over the head of mannequin) mortality bioassays. In contact plus fumigant mortality bioassay, essential oils from eucalyptus (0.225 mg/cm2) and clove (1.149 mg/cm2) were less effective than either d-phenothrin (0.0029 mg/cm2) or pyrethrum (0.0025 mg/cm2) based on 6-h median lethal concentration values. However, the efficacies of eucalyptus and clove oils were almost identical against females fromn both strains, despite high levels of resistance of the BR-HL females to d-phenothrin (resistance ratio, 667) and pyrethrum (resistance ratio, 754). In human hair wig mortality bioassay, eucalyptus oil spray treatment gave better control efficacy than either spray treatment with clove oil alone or their binary mixtures. Thus, eucalyptus applied as 8% sprays (15 or 20 ml) appears to provide effective protection against pediculosis even to insecticide-resistant head louse populations. Once the safety issues resolved, covering the treated hair and scalp with bath shower cap or hat would ensure the fumigant action of the essential oil. PMID:20496586
Martinů, Jana; Roubová, V.; Nováková, M.; Smith, V. S.; Hypša, Václav; Štefka, Jan
Roč. 62, FEB 13 2015 (2015), 016. ISSN 1803-6465 R&D Projects: GA ČR GPP506/12/P529 Institutional support: RVO:60077344 Keywords : ectoparasite * population genetics * coevolution * Polypax * Myrsidea * evolution * Europe * Galapagos Subject RIV: EG - Zoology
María M. Gutiérrez; Stefanazzi, Natalia; Jorge WERDIN GONZÁLEZ; Verónica BENZI; Adriana A. Ferrero
Los aceites esenciales de hojas se aislaron por hidrodestilación. Los bioensayos se realizaron a 28 ± 2 ºC, 65% ± 5 H.R y en oscuridad. Se utilizaron cajas de Petri de vidrio (5cm de diámetro), en sus bases se colocaron 50 mL de los aceites puros. La caja se cubrió con una tapa plástica perforada que posee un tejido de hilo. Sobre este se liberaron 10 insectos protegidos por una segunda caja con diámetro equivalente. El conjunto de cajas se cerró con cinta adhesiva. Se realizaron tres réplica...
We report a male patient of 24 years old with itching at groin and pubis. Pubic hair test showed the presence of lices (fig.2-4).Pediculosis is an infestation of man and animals by insects Anoplura (Lice) Vampire ectoparasites. It´s important poor hygiene, promiscuity, fomites, sexual transmission. Etiology: Pediculus humanus capitis, Human Pediculus corporis, Phthirus pubis or pubic lice. Clinically pediculosis can be classify in :head lice, body lice, pubic pediculosis. Phthirus pubis or ...
Fragmented mitochondrial genomes of the rat lice, Polyplax asiatica and Polyplax spinulosa: intra-genus variation in fragmentation pattern and a possible link between the extent of fragmentation and the length of life cycle
Dong, Wen-Ge; Song, Simon; Jin, Dao-Chao; Guo, Xian-Guo; Shao, Renfu
Background Blood-sucking lice (suborder Anoplura) parasitize eutherian mammals with 67% of the 540 described species found on rodents. The five species of blood-sucking lice that infest humans and pigs have fragmented mitochondrial genomes and differ substantially in the extent of fragmentation. To understand whether, or not, any life-history factors are linked to such variation, we sequenced the mt genomes of Polyplax asiatica and Polyplax spinulosa, collected from the greater bandicoot rat,...
Silvio Alencar Marques
Full Text Available White piedra is a superficial mycosis caused by the genus Trichosporon. It is characterized by nodules on the hair shaft. Pediculosis capitis is caused by Pediculus humanus var. capitis of the suborder Anoplura. Whereas pediculosis is a common infestation, clinical reports of white piedra are rare. Molecular biology procedures identified T. inkin as the agent of white piedra in this case report. The authors present associations between the two diseases in the same patient in order to highlight their clinical differences.Piedra branca é micose superficial causada pelo gênero Trichosporon e caracterizada por nódulos aderidos à haste do pelo. Pediculose capitis é causada pelo Pediculus humanus var. capitis pertencente à subordem Anoplura. Enquanto que a pediculose é enfermidade comum, relatos clínicos de piedra branca são raros. Técnicas de biologia molecular identificaram o agente de piedra branca do presente relato como T.inkin. Os autores apresentam associação de ambas as infestações no mesmo paciente para salientar seus aspectos clínicos distintos.
Full Text Available We report a male patient of 24 years old with itching at groin and pubis. Pubic hair test showed the presence of lices (fig.2-4.Pediculosis is an infestation of man and animals by insects Anoplura (Lice Vampire ectoparasites. It´s important poor hygiene, promiscuity, fomites, sexual transmission. Etiology: Pediculus humanus capitis, Human Pediculus corporis, Phthirus pubis or pubic lice. Clinically pediculosis can be classify in :head lice, body lice, pubic pediculosis. Phthirus pubis or crab lice is the agent of pediculus pubis, the sites affected are pubic region other sites as thighs, trunk, armpit, eyebrows, eyelashes, beard and scalp. Pruritus hematic crusts, excoriations, stains 0.5 cm -1 blue cerulean spots may be associated with other STD. The diagnosis is based in the clinical aspect and observes the parasite. Phthirus short pubis or pubic lice parasite, it´s size: 0.8-1.2 mm his first legs resemble those of a crab with sucking, slow walking 10 cm / min. Treatment is based on head lice or nits destruction benzyl benzoate 25% 8 to 12 hrs once, crotramiton 10% 1 / day x 8 days and ivermectin 200 micrograms / kg in a single dose.
Lehnert, K.; Raga, J. A.; Siebert, U.
Parasites were collected from 107 harbour seals ( Phoca vitulina) found on the coasts of Schleswig-Holstein, Germany, between 1997 and 2000. The prevalence of the parasites and their associated pathology were investigated. Eight species of parasites, primarily nematodes, were identified from the examined organs: two anisakid nematodes ( Pseudoterranova decipiens (sensu lato) , Contracaecum osculatum (sensu lato)) from the stomach, Otostrongylus circumlitus (Crenosomatidae) and Parafilaroides gymnurus (Filaroididae) from the respiratory tract, one filarioid nematode ( Acanthocheilonema spirocauda) from the heart, two acanthocephalans, Corynosoma strumosum and C. semerme (Polymorphidae), from the intestine and an ectoparasite, Echinophthirius horridus (Anoplura, Insecta). Lungworm infection was the most prominent parasitological finding and secondary bacterial bronchopneumonia the most pathogenic lesion correlated with the parasites. Heavy nematode burdens in the respiratory tract were highly age-related and more frequent in young seals. A positive correlation was observed between high levels of pulmonary infection and severity of bronchopneumonia. The prevalence of lungworms in this study was higher than in seals that died during the 1988/1989 Phocine Distemper Virus epidemic, and the prevalence of acanthocephalans and heartworms had decreased compared to findings from the first die-off.
Karbowiak, Grzegorz; Demiaszkiewicz, Aleksander W; Pyziel, Anna M; Wita, Irena; Moskwa, Bożena; Werszko, Joanna; Bień, Justyna; Goździk, Katarzyna; Lachowicz, Jacek; Cabaj, Władysław
During the current century, 88 species of parasites have been recorded in Bison bonasus. These are 22 species of protozoa (Trypanosoma wrublewskii, T. theileri, Giardia sp., Sarcocystis cruzi, S. hirsuta, S. hominis, S. fusiformis, Neospora caninum, Toxoplasma gondii, Cryptosporidium sp., Eimeria cylindrica, E. subspherica, E. bovis, E. zuernii, E. canadensis, E. ellipsoidalis, E. alabamensis, E. bukidnonensis, E. auburnensis, E. pellita, E. brasiliensis, Babesia divergens), 4 trematodes species (Dicrocoelium dendriticum, Fasciola hepatica, Parafasciolopsis fasciolaemorpha, Paramphistomum cervi), 4 cestodes species (Taenia hydatigena larvae, Moniezia benedeni, M. expansa, Moniezia sp.), 43 nematodes species (Bunostomum trigonocephalum, B. phlebotomum, Chabertia ovina, Oesophagostomum radiatum, O. venulosum, Dictyocaulus filaria, D.viviparus, Nematodirella alcidis, Nematodirus europaeus, N. helvetianus, N. roscidus, N. filicollis, N. spathiger, Cooperia oncophora, C. pectinata, C. punctata, C. surnabada, Haemonchus contortus, Mazamastrongylus dagestanicus, Ostertagia lyrata, O. ostertagi, O. antipini, O. leptospicularis, O. kolchida, O. circumcincta, O. trifurcata, Spiculopteragia boehmi, S. mathevossiani, S. asymmetrica, Trichostrongylus axei, T. askivali, T. capricola, T. vitrinus, Ashworthius sidemi, Onchocerca lienalis, O. gutturosa, Setaria labiatopapillosa, Gongylonema pulchrum, Thelazia gulosa, T. skrjabini, T. rhodesi, Aonchotheca bilobata, Trichuris ovis), 7 mites (Demodex bisonianus, D. bovis, Demodex sp., Chorioptes bovis, Psoroptes equi, P. ovis, Sarcoptes scabiei), 4 Ixodidae ticks (Ixodes ricinus, I. persulcatus, I. hexagonus, Dermacentor reticulatus), 1 Mallophaga species (Bisonicola sedecimdecembrii), 1 Anoplura (Haematopinus eurysternus), and 2 Hippoboscidae flies (Lipoptena cervi, Melophagus ovinus). There are few monoxenous parasites, many typical for cattle and many newly acquired from Cervidae. PMID:25119348
Allen, Julie M; Burleigh, J Gordon; Light, Jessica E; Reed, David L
Phylogenetic trees can reveal the origins of endosymbiotic lineages of bacteria and detect patterns of co-evolution with their hosts. Although taxon sampling can greatly affect phylogenetic and co-evolutionary inference, most hypotheses of endosymbiont relationships are based on few available bacterial sequences. Here we examined how different sampling strategies of Gammaproteobacteria sequences affect estimates of the number of endosymbiont lineages in parasitic sucking lice (Insecta: Phthirapatera: Anoplura). We estimated the number of louse endosymbiont lineages using both newly obtained and previously sequenced 16S rDNA bacterial sequences and more than 42,000 16S rDNA sequences from other Gammaproteobacteria. We also performed parametric and nonparametric bootstrapping experiments to examine the effects of phylogenetic error and uncertainty on these estimates. Sampling of 16S rDNA sequences affects the estimates of endosymbiont diversity in sucking lice until we reach a threshold of genetic diversity, the size of which depends on the sampling strategy. Sampling by maximizing the diversity of 16S rDNA sequences is more efficient than randomly sampling available 16S rDNA sequences. Although simulation results validate estimates of multiple endosymbiont lineages in sucking lice, the bootstrap results suggest that the precise number of endosymbiont origins is still uncertain. PMID:27547523
Full Text Available Background: Pediculus capitis (Anoplura: Pediculidae or head louse is an obligate ectoparasite transmitted mainly through physical contact. This study was conducted to survey the prevalence of head lice infestation rate and some risk factors in Primary School pupils, in Khajeh City East Azerbaijan Province, IranMethods: We selected 20 primary schools of Khajeh City during 2008 and 2009. Totally 500 pupils including 200 boys and 300 girls from all grade 1-5 were selected by multistage, systematic random sampling in rural areas of Khajeh City and were examined for lice. In addition, a standard questionnaire recorded information about demographic features of each pupil. Results were analyzed by SPSS software.Results: The total prevalence of head lice infestation in this study was 4.8%. and the prevalence rate was significantly higher in girls (6.66% than in boys (2%. Epidemiological factors such as: sex, school grade, family size, parent's education, type of house, hair washing (per week, number of using comb per day, were evaluated and results showed significant difference in head lice infestation and sex, school grade ,family size ,father education ,and type of house (P< 0.05.Conclusion: Pediculosis is a public health problem in many parts of the world, and due to the higher prevalence of pediculosis in crowded families, family by lower levels of father's education and socioeconomic status in our study and rural area, it is necessary to give health education for families to prevent of pediculosis in this area.
Full Text Available Abstract Background The gene composition, gene order and structure of the mitochondrial genome are remarkably stable across bilaterian animals. Lice (Insecta: Phthiraptera are a major exception to this genomic stability in that the canonical single chromosome with 37 genes found in almost all other bilaterians has been lost in multiple lineages in favour of multiple, minicircular chromosomes with less than 37 genes on each chromosome. Results Minicircular mt genomes are found in six of the ten louse species examined to date and three types of minicircles were identified: heteroplasmic minicircles which coexist with full sized mt genomes (type 1; multigene chromosomes with short, simple control regions, we infer that the genome consists of several such chromosomes (type 2; and multiple, single to three gene chromosomes with large, complex control regions (type 3. Mapping minicircle types onto a phylogenetic tree of lice fails to show a pattern of their occurrence consistent with an evolutionary series of minicircle types. Analysis of the nuclear-encoded, mitochondrially-targetted genes inferred from the body louse, Pediculus, suggests that the loss of mitochondrial single-stranded binding protein (mtSSB may be responsible for the presence of minicircles in at least species with the most derived type 3 minicircles (Pediculus, Damalinia. Conclusions Minicircular mt genomes are common in lice and appear to have arisen multiple times within the group. Life history adaptive explanations which attribute minicircular mt genomes in lice to the adoption of blood-feeding in the Anoplura are not supported by this expanded data set as minicircles are found in multiple non-blood feeding louse groups but are not found in the blood-feeding genus Heterodoxus. In contrast, a mechanist explanation based on the loss of mtSSB suggests that minicircles may be selectively favoured due to the incapacity of the mt replisome to synthesize long replicative products
Full Text Available "n "nBackground: Pediculus capitis (Anoplura: Pediculidae or head louse is an obligate ectoparasite transmitted mainly through physical contact. This study was conducted to survey the prevalence of head lice infestation rate and some risk factors in Primary School pupils, in Khajeh City East Azerbaijan Province, Iran "n "nMethods: We selected 20 primary schools of Khajeh City during 2008 and 2009. Totally 500 pupils including 200 boys and 300 girls from all grade 1-5 were selected by multistage, systematic random sampling in rural areas of Khajeh City and were examined for lice. In addition, a standard questionnaire recorded information about demographic features of each pupil. Results were analyzed by SPSS software. "n "nResults: The total prevalence of head lice infestation in this study was 4.8%. and the prevalence rate was significantly higher in girls (6.66% than in boys (2%. Epidemiological factors such as: sex, school grade, family size, parent's education, type of house, hair washing (per week, number of using comb per day, were evaluated and results showed significant difference in head lice infestation and sex, school grade ,family size ,father education ,and type of house (P< 0.05. "n "nConclusion: Pediculosis is a public health problem in many parts of the world, and due to the higher prevalence of pediculosis in crowded families, family by lower levels of father's education and socioeconomic status in our study and rural area, it is necessary to give health education for families to prevent of pediculosis in this area.
Leonardi, Maria Soledad; Aznar, F Javier; Crespo, Enrique A; Lazzari, Claudio R
Despite the incredible success of insects in colonizing almost every habitat, they remain virtually absent in one major environment--the open sea. A variety of hypotheses have been raised to explain why just a few insect species are present in the ocean, but none of them appears to be fully explanatory. Lice belonging to the family Echinophthiriidae are ectoparasites on different species of pinnipeds and river otters, i.e. they have amphibious hosts, who regularly perform long excursions into the open sea reaching depths of hundreds of meters (thousands of feets). Consequently, lice must be able to support not only changes in their surrounding media, but also extreme variations in hydrostatic pressure as well as breathing in a low oxygen atmosphere. In order to shed some light on the way lice can survive during the diving excursions of their hosts, we have performed a series of experiments to test the survival capability of different instars of Antarctophthirus microchir (Phthiraptera: Anoplura) from South American sea lions Otaria flavescens, when submerged into seawater. These experiments were aimed at analyzing: (a) immersion tolerance along the louse life; (b) lice's ability to obtain oxygen from seawater; (c) physiological responses and mechanisms involved in survival underwater. Our experiments showed that the forms present in non-diving pups--i.e. eggs and first-instar nymphs--were unable to tolerate immersion in water, while following instars and adults, all usually found in diving hosts, supported it very well. Furthermore, as long as the level of oxygen dissolved in water was higher, the lice survival capability underwater increased, and the recovery period after returning to air declined. These results are discussed in relation to host ecology, host exploitation and lice functional morphology. PMID:25449903
董文鸽; 郭宪国; 门兴元; 钱体军; 吴滇
An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004.From investigation sites, 3 303 small mammal hosts were captured and identified into 7families, 15 genera and 21 species in 4 orders (Rodentia, Insectivora, Scandentia and Carnivora), while 14 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura. The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain.The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity,abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking li ce and their corresponding hosts. A certain species of hosts usually have theirfixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mam mal host in different oriented areas of Erhai Lake are homologous. The results stronglysuggest a close relationship of co-evolution between sucking lice and their hosts.
Laurie R. Godfrey
Full Text Available The mouse lemur Microcebus griseorufus at the Beza Mahafaly Special Reserve and general vicinity in southwestern Madagascar were surveyed for ectoparasites as part of a year-long behavioral and ecological study. Of 249 individual mouse lemurs examined, 74 were positively identified as hosting ectoparasites. Ticks from 20 mouse lemurs and lice in a subset of two individuals captured in a 90 ha gallery forest (Parcel 1 were preserved in 70 % ethanol or EDTA and stored for analysis and for identification. Two species of Haemaphysalis ticks are represented in the sample, H. lemuris and possibly H. simplex, a tick previously reported on tenrecs, birds and rats. Synchronous development of ticks may pose a risk for vector - borne diseases at the reserve especially during the dry season. The louse represented in the sample belongs to the order Anoplura (sucking lice, and resembles Lemurpediculus verruculosus, previously reported on Microcebus rufus in eastern Madagascar. RÉSUMÉUn inventaire d’ectoparasites a été réalisé dans le cadre d’une étude de longue durée portant sur le comportement et l’écologie de Microcebus griseorufus dans trois parcelles forestières de Beza Mahafaly et ses environs. Sur les 249 microcèbes observés, 74 individus étaient infestés d’ectoparasites. La majorité de ces individus infestés, soit 97,3 %, provenait de la parcelle 1 de la réserve. Des poux et des tiques recensés sur ces animaux ont été immédiatement retirés puis préservés dans l’éthanol 70 % ou dans l’EDTA à des fins d’analyse et d’identification. Deux espèces de tiques ont été identifiées, Haemaphysalis lemuris et probablement H. simplex, cette dernière n’était préalablement connue que pour infester les tenrecs, les oiseaux et les rats.Les rongeurs jouent un rôle significatif en tant qu’hôtes pour près de la moitié des larves et des nymphes d’ixodes de tiques du monde, y compris H. simplex. Les rats sont connus