Identification of high risk areas for avian influenza outbreaks in California using disease distribution models.

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Jaber Belkhiria

Full Text Available The coexistence of different types of poultry operations such as free range and backyard flocks, large commercial indoor farms and live bird markets, as well as the presence of many areas where wild and domestic birds co-exist, make California susceptible to avian influenza outbreaks. The 2014-2015 highly pathogenic Avian Influenza (HPAI outbreaks affecting California and other states in the United States have underscored the need for solutions to protect the US poultry industry against this devastating disease. We applied disease distribution models to predict where Avian influenza is likely to occur and the risk for HPAI outbreaks is highest. We used observations on the presence of Low Pathogenic Avian influenza virus (LPAI in waterfowl or water samples at 355 locations throughout the state and environmental variables relevant to the disease epidemiology. We used two algorithms, Random Forest and MaxEnt, and two data-sets Presence-Background and Presence-Absence data. The models performed well (AUCc > 0.7 for testing data, particularly those using Presence-Background data (AUCc > 0.85. Spatial predictions were similar between algorithms, but there were large differences between the predictions with Presence-Absence and Presence-Background data. Overall, predictors that contributed most to the models included land cover, distance to coast, and broiler farm density. Models successfully identified several counties as high-to-intermediate risk out of the 8 counties with observed outbreaks during the 2014-2015 HPAI epizootics. This study provides further insights into the spatial epidemiology of AI in California, and the high spatial resolution maps may be useful to guide risk-based surveillance and outreach efforts.

Consequences of outbreaks of influenza A virus in farmed mink (Neovison vison) in Denmark in 2009 and 2010

DEFF Research Database (Denmark)

Chriél, Mariann; Jensen, Trine Hammer; Hjulsager, Charlotte Kristiane

2012-01-01

Influenza in mink (Neovison vison) is assumed to be rare, but outbreaks have previously been reported in farmed mink. The first report was from Swedish mink farms in 1984 which was caused by influenza A virus H10N4 of avian origin. In 2009 and 2010 outbreaks of respiratory disease were seen...... in several Danish mink farms. In all of the farms, the clinical symptoms were upper respiratory tract symptoms with sneezing and coughing as the most dominant symptoms. Peracute deaths were seen in mink without any clinical symptoms. Influenza H3N2 was found detected by PCR in the lungs from diseased mink...... and four of these farms used feed medication in three weeks. The farmers, however, noted that the medication had little or no effect. The most plausible way of transmission of the influenza is from the raw untreated pig waste containing lungs used in the production of mink feed. Because the first clinical...

Consequences of outbreaks of influenza A virus in farmed mink (Neovison vison) in Denmark in 2009 and 2010

DEFF Research Database (Denmark)

Chriél, Mariann; Jensen, Trine Hammer; Hjulsager, Charlotte Kristiane

2012-01-01

and four of these farms used feed medication in three weeks. The farmers, however, noted that the medication had little or no effect. The most plausible way of transmission of the influenza is from the raw untreated pig waste containing lungs used in the production of mink feed. Because the first clinical......Influenza in mink (Neovison vison) is assumed to be rare, but outbreaks have previously been reported in farmed mink. The first report was from Swedish mink farms in 1984 which was caused by influenza A virus H10N4 of avian origin. In 2009 and 2010 outbreaks of respiratory disease were seen...... in several Danish mink farms. In all of the farms, the clinical symptoms were upper respiratory tract symptoms with sneezing and coughing as the most dominant symptoms. Peracute deaths were seen in mink without any clinical symptoms. Influenza H3N2 was found detected by PCR in the lungs from diseased mink...

Novel Use of Flu Surveillance Data: Evaluating Potential of Sentinel Populations for Early Detection of Influenza Outbreaks.

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Daughton, Ashlynn R; Velappan, Nileena; Abeyta, Esteban; Priedhorsky, Reid; Deshpande, Alina

2016-01-01

Influenza causes significant morbidity and mortality each year, with 2-8% of weekly outpatient visits around the United States for influenza-like-illness (ILI) during the peak of the season. Effective use of existing flu surveillance data allows officials to understand and predict current flu outbreaks and can contribute to reductions in influenza morbidity and mortality. Previous work used the 2009-2010 influenza season to investigate the possibility of using existing military and civilian surveillance systems to improve early detection of flu outbreaks. Results suggested that civilian surveillance could help predict outbreak trajectory in local military installations. To further test that hypothesis, we compare pairs of civilian and military outbreaks in seven locations between 2000 and 2013. We find no predictive relationship between outbreak peaks or time series of paired outbreaks. This larger study does not find evidence to support the hypothesis that civilian data can be used as sentinel surveillance for military installations. We additionally investigate the effect of modifying the ILI case definition between the standard Department of Defense definition, a more specific definition proposed in literature, and confirmed Influenza A. We find that case definition heavily impacts results. This study thus highlights the importance of careful selection of case definition, and appropriate consideration of case definition in the interpretation of results.

Comparison of ARIMA and Random Forest time series models for prediction of avian influenza H5N1 outbreaks.

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Kane, Michael J; Price, Natalie; Scotch, Matthew; Rabinowitz, Peter

2014-08-13

Time series models can play an important role in disease prediction. Incidence data can be used to predict the future occurrence of disease events. Developments in modeling approaches provide an opportunity to compare different time series models for predictive power. We applied ARIMA and Random Forest time series models to incidence data of outbreaks of highly pathogenic avian influenza (H5N1) in Egypt, available through the online EMPRES-I system. We found that the Random Forest model outperformed the ARIMA model in predictive ability. Furthermore, we found that the Random Forest model is effective for predicting outbreaks of H5N1 in Egypt. Random Forest time series modeling provides enhanced predictive ability over existing time series models for the prediction of infectious disease outbreaks. This result, along with those showing the concordance between bird and human outbreaks (Rabinowitz et al. 2012), provides a new approach to predicting these dangerous outbreaks in bird populations based on existing, freely available data. Our analysis uncovers the time-series structure of outbreak severity for highly pathogenic avain influenza (H5N1) in Egypt.

Hospital-acquired influenza: a synthesis using the Outbreak Reports and Intervention Studies of Nosocomial Infection (ORION) statement.

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Voirin, N; Barret, B; Metzger, M-H; Vanhems, P

2009-01-01

Nosocomial influenza outbreaks occur in almost all types of hospital wards, and their consequences for patients and hospitals in terms of morbidity, mortality and costs are considerable. The source of infection is often unknown, since any patient, healthcare worker (HCW) or visitor is capable of transmitting it to susceptible persons within hospitals. Nosocomial influenza outbreak investigations should help to identify the source of infection, prevent additional cases, and increase our knowledge of disease control to face future outbreaks. However, such outbreaks are probably underdetected and underreported, making routes of transmission difficult to track and describe with precision. In addition, the absence of standardised information in the literature limits comparison between studies and better understanding of disease dynamics. In this study, reports of nosocomial influenza outbreaks are synthesised according to the ORION guidelines to highlight existing knowledge in relation to the detection of influenza cases, evidence of transmission between patients and HCWs and measures of disease incidence. Although a body of evidence has confirmed that influenza spreads within hospitals, we should improve clinical and virological confirmation and initiate active surveillance and quantitative studies to determine incidence rates in order to assess the risk to patients.

2009 pandemic influenza A (H1N1 virus outbreak and response--Rwanda, October, 2009-May, 2010.

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Justin Wane

Full Text Available BACKGROUND: In October 2009, the first case of pandemic influenza A(H1N1pdm09 (pH1N1 was confirmed in Kigali, Rwanda and countrywide dissemination occurred within several weeks. We describe clinical and epidemiological characteristics of this epidemic. METHODS: From October 2009 through May 2010, we undertook epidemiologic investigations and response to pH1N1. Respiratory specimens were collected from all patients meeting the WHO case definition for pH1N1, which were tested using CDC's real time RT-PCR protocol at the Rwandan National Reference Laboratory (NRL. Following documented viral transmission in the community, testing focused on clinically severe and high-risk group suspect cases. RESULTS: From October 9, 2009 through May 31, 2010, NRL tested 2,045 specimens. In total, 26% (n = 532 of specimens tested influenza positive; of these 96% (n = 510 were influenza A and 4% (n = 22 were influenza B. Of cases testing influenza A positive, 96.8% (n = 494, 3% (n = 15, and 0.2% (n = 1 were A(H1N1pdm09, Seasonal A(H3 and Seasonal A(non-subtyped, respectively. Among laboratory-confirmed cases, 263 (53.2% were children <15 years and 275 (52% were female. In total, 58 (12% cases were hospitalized with mean duration of hospitalization of 5 days (Range: 2-15 days. All cases recovered and there were no deaths. Overall, 339 (68% confirmed cases received oseltamivir in any setting. Among all positive cases, 26.9% (143/532 were among groups known to be at high risk of influenza-associated complications, including age <5 years 23% (122/532, asthma 0.8% (4/532, cardiac disease 1.5% (8/532, pregnancy 0.6% (3/532, diabetes mellitus 0.4% (2/532, and chronic malnutrition 0.8% (4/532. CONCLUSIONS: Rwanda experienced a PH1N1 outbreak which was epidemiologically similar to PH1N1 outbreaks in the region. Unlike seasonal influenza, children <15 years were the most affected by pH1N1. Lessons learned from the outbreak response included the need to

Building-level analyses to prospectively detect influenza outbreaks in long-term care facilities: New York City, 2013-2014.

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Levin-Rector, Alison; Nivin, Beth; Yeung, Alice; Fine, Annie D; Greene, Sharon K

2015-08-01

Timely outbreak detection is necessary to successfully control influenza in long-term care facilities (LTCFs) and other institutions. To supplement nosocomial outbreak reports, calls from infection control staff, and active laboratory surveillance, the New York City (NYC) Department of Health and Mental Hygiene implemented an automated building-level analysis to proactively identify LTCFs with laboratory-confirmed influenza activity. Geocoded addresses of LTCFs in NYC were compared with geocoded residential addresses for all case-patients with laboratory-confirmed influenza reported through passive surveillance. An automated daily analysis used the geocoded building identification number, approximate text matching, and key-word searches to identify influenza in residents of LTCFs for review and follow-up by surveillance coordinators. Our aim was to determine whether the building analysis improved prospective outbreak detection during the 2013-2014 influenza season. Of 119 outbreaks identified in LTCFs, 109 (92%) were ever detected by the building analysis, and 55 (46%) were first detected by the building analysis. Of the 5,953 LTCF staff and residents who received antiviral prophylaxis during the 2013-2014 season, 929 (16%) were at LTCFs where outbreaks were initially detected by the building analysis. A novel building-level analysis improved influenza outbreak identification in LTCFs in NYC, prompting timely infection control measures. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Outbreak of influenza in an overseas student travel group--Taiwan 2008.

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Tsou, Tsung-Pei; Lin, Chien-Hui; Lo, Yi-Chun; Li, Yi-Syue; Chiu, Chan-Hsien

2010-05-01

Influenza is a frequent cause of acute respiratory illness (ARI). In July 2008, we conducted a retrospective cohort study to investigate an influenza outbreak occurring in an overland travel group of overseas students. ARI was defined as the presence of any respiratory symptom such as cough, rhinorrhoea, sore throat or stuffy nose. Influenza-like illness (ILI) was defined as ARI plus fever > or =38 degrees C. Throat swabs were taken from symptomatic participants and a real-time polymerase chain reaction (RT-PCR) was performed. One hundred and seventy participants were interviewed. Forty-four (26%) had an ARI and 22 (13%) had an ILI. Of the 33 specimens collected, 18 (54%) were positive for influenza A/H3N2. Taiwanese group leaders had increased risk of acquiring both ARI and ILI (ARI relative risk (RR) 2.2, 95% confidence interval (CI) 1.3-3.7 and ILI RR 2.8, 95% CI 1.2-6.3). Fifteen participants were vaccinated. The vaccine effectiveness was 52% for ILI (p = 0.70). The outbreak stopped after cohorting and the use of surgical masks. Vaccination appeared to be effective in preventing infection.

Perceptions of vulnerability to a future outbreak: a study of horse managers affected by the first Australian equine influenza outbreak

Science.gov (United States)

2013-01-01

Background A growing body of work shows the benefits of applying social cognitive behavioural theory to investigate infection control and biosecurity practices. Protection motivation theory has been used to predict protective health behaviours. The theory outlines that a perception of a lack of vulnerability to a disease contributes to a reduced threat appraisal, which results in poorer motivation, and is linked to poorer compliance with advised health protective behaviours. This study, conducted following the first-ever outbreak of equine influenza in Australia in 2007, identified factors associated with horse managers’ perceived vulnerability to a future equine influenza outbreak. Results Of the 200 respondents, 31.9% perceived themselves to be very vulnerable, 36.6% vulnerable and 31.4% not vulnerable to a future outbreak of equine influenza. Multivariable logistic regression modelling revealed that managers involved in horse racing and those on rural horse premises perceived themselves to have low levels of vulnerability. Managers of horse premises that experienced infection in their horses in 2007 and those seeking infection control information from specific sources reported increased levels of perceived vulnerability to a future outbreak. Conclusion Different groups across the horse industry perceived differing levels of vulnerability to a future outbreak. Increased vulnerability contributes to favourable infection control behaviour and hence these findings are important for understanding uptake of recommended infection control measures. Future biosecurity communication strategies should be delivered through information sources suitable for the horse racing and rural sectors. PMID:23902718

Perceptions of vulnerability to a future outbreak: a study of horse managers affected by the first Australian equine influenza outbreak.

Science.gov (United States)

Schemann, Kathrin; Firestone, Simon M; Taylor, Melanie R; Toribio, Jenny-Ann L M L; Ward, Michael P; Dhand, Navneet K

2013-07-31

A growing body of work shows the benefits of applying social cognitive behavioural theory to investigate infection control and biosecurity practices. Protection motivation theory has been used to predict protective health behaviours. The theory outlines that a perception of a lack of vulnerability to a disease contributes to a reduced threat appraisal, which results in poorer motivation, and is linked to poorer compliance with advised health protective behaviours. This study, conducted following the first-ever outbreak of equine influenza in Australia in 2007, identified factors associated with horse managers' perceived vulnerability to a future equine influenza outbreak. Of the 200 respondents, 31.9% perceived themselves to be very vulnerable, 36.6% vulnerable and 31.4% not vulnerable to a future outbreak of equine influenza. Multivariable logistic regression modelling revealed that managers involved in horse racing and those on rural horse premises perceived themselves to have low levels of vulnerability. Managers of horse premises that experienced infection in their horses in 2007 and those seeking infection control information from specific sources reported increased levels of perceived vulnerability to a future outbreak. Different groups across the horse industry perceived differing levels of vulnerability to a future outbreak. Increased vulnerability contributes to favourable infection control behaviour and hence these findings are important for understanding uptake of recommended infection control measures. Future biosecurity communication strategies should be delivered through information sources suitable for the horse racing and rural sectors.

Modeling and roles of meteorological factors in outbreaks of highly pathogenic avian influenza H5N1.

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Paritosh K Biswas

Full Text Available The highly pathogenic avian influenza A virus subtype H5N1 (HPAI H5N1 is a deadly zoonotic pathogen. Its persistence in poultry in several countries is a potential threat: a mutant or genetically reassorted progenitor might cause a human pandemic. Its world-wide eradication from poultry is important to protect public health. The global trend of outbreaks of influenza attributable to HPAI H5N1 shows a clear seasonality. Meteorological factors might be associated with such trend but have not been studied. For the first time, we analyze the role of meteorological factors in the occurrences of HPAI outbreaks in Bangladesh. We employed autoregressive integrated moving average (ARIMA and multiplicative seasonal autoregressive integrated moving average (SARIMA to assess the roles of different meteorological factors in outbreaks of HPAI. Outbreaks were modeled best when multiplicative seasonality was incorporated. Incorporation of any meteorological variable(s as inputs did not improve the performance of any multivariable models, but relative humidity (RH was a significant covariate in several ARIMA and SARIMA models with different autoregressive and moving average orders. The variable cloud cover was also a significant covariate in two SARIMA models, but air temperature along with RH might be a predictor when moving average (MA order at lag 1 month is considered.

Early-warning signals for an outbreak of the influenza pandemic

Science.gov (United States)

Ren, Di; Gao, Jie

2011-12-01

Over the course of human history, influenza pandemics have been seen as major disasters, so studies on the influenza virus have become an important issue for many experts and scholars. Comprehensive research has been performed over the years on the biological properties, chemical characteristics, external environmental factors and other aspects of the virus, and some results have been achieved. Based on the chaos game representation walk model, this paper uses the time series analysis method to study the DNA sequences of the influenza virus from 1913 to 2010, and works out the early-warning signals indicator value for the outbreak of an influenza pandemic. The variances in the CGR walk sequences for the pandemic years (or + -1 to 2 years) are significantly higher than those for the adjacent years, while those in the non-pandemic years are usually smaller. In this way we can provide an influenza early-warning mechanism so that people can take precautions and be well prepared prior to a pandemic.

Effect of antiviral prophylaxis on influenza outbreaks om aged care facilities in three local health districts in New South Wales, Australia, 2014

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Tony Merritt

2016-02-01

Full Text Available Background: There was a record number (n = 111 of influenza outbreaks in aged care facilities in New South Wales, Australia during 2014. To determine the impact of antiviral prophylaxis recommendations in practice, influenza outbreak data were compared for facilities in which antiviral prophylaxis and treatment were recommended and for those in which antivirals were recommended for treatment only. Methods: Routinely collected outbreak data were extracted from the Notifiable Conditions Information Management System for two Local Health Districts where antiviral prophylaxis was routinely recommended and one Local Health District where antivirals were recommended for treatment but not routinely for prophylaxis. Data collected on residents included counts of influenza-like illness, confirmed influenza, hospitalizations and related deaths. Dates of onset, notification, influenza confirmation and antiviral recommendations were also collected for analysis. The Mann–Whitney U test was used to assess the significance of differences between group medians for key parameters. Results: A total of 41 outbreaks (12 in the prophylaxis group and 29 in the treatment-only group were included in the analysis. There was no significant difference in overall outbreak duration; outbreak duration after notification; or attack, hospitalization or case fatality rates between the two groups. The prophylaxis group had significantly higher cases with influenza-like illness (P = 0.03 and cases recommended antiviral treatment per facility (P = 0.01. Discussion: This study found no significant difference in key outbreak parameters between the two groups. However, further high quality evidence is needed to guide the use of antivirals in responding to influenza outbreaks in aged care facilities.

Swine flu - A pandemic outbreak

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Jini George

Full Text Available Hippocrates had described influenza like outbreak in 412 B.C. and since then repeated influenza like epidemics and pandemics have been recorded in recent times. One of the greatest killers of all time was the pandemic of swine flu (Spanish flu of 1918-1919, when 230 million people died. Annual influenza epidemics are estimated to affect 5–15% of the global population, resulting in severe illness in 3–5 million patients causing 250,000–500,000 deaths worldwide. Severe illness and deaths occur mainly in the high-risk populations of infants, the elderly and chronically ill patients. The 2009 outbreak of swine flu is thought to be a mutation more specifically a reassortment of four known strains of influenza A virus subtype H1N1; one endemic in humans, one endemic in birds, and two endemic in pigs. WHO officially declared the outbreak to be a pandemic on June 11, 2009, but stressed that the new designation was a result of the global "spread of the virus," not its severity. [Vet World 2009; 2(12.000: 472-474

Review of highly pathogenic avian influenza outbreaks in poultry in ...

African Journals Online (AJOL)

All the confirmed highly pathogenic avian influenza cases that were diagnosed in Zaria at the Veterinary Teaching Hospital, Ahmadu Bello University, Zaria, Nigeria, were reviewed in this study. The outbreaks occurred between the months of December, 2006 and March, 2007. The clinical signs and postmortem lesions ...

Intentions to perform non-pharmaceutical protective behaviors during influenza outbreaks in Sweden: a cross-sectional study following a mass vaccination campaign.

Science.gov (United States)

Timpka, Toomas; Spreco, Armin; Gursky, Elin; Eriksson, Olle; Dahlström, Örjan; Strömgren, Magnus; Ekberg, Joakim; Pilemalm, Sofie; Karlsson, David; Hinkula, Jorma; Holm, Einar

2014-01-01

Failure to incorporate the beliefs and attitudes of the public into theoretical models of preparedness has been identified as a weakness in strategies to mitigate infectious disease outbreaks. We administered a cross-sectional telephone survey to a representative sample (n = 443) of the Swedish adult population to examine whether self-reported intentions to improve personal hygiene and increase social distancing during influenza outbreaks could be explained by trust in official information, self-reported health (SF-8), sociodemographic factors, and determinants postulated in protection motivation theory, namely threat appraisal and coping appraisal. The interviewees were asked to make their appraisals for two scenarios: a) an influenza with low case fatality and mild lifestyle impact; b) severe influenza with high case fatality and serious disturbances of societal functions. Every second respondent (50.0%) reported high trust in official information about influenza. The proportion that reported intentions to take deliberate actions to improve personal hygiene during outbreaks ranged between 45-85%, while less than 25% said that they intended to increase social distancing. Multiple logistic regression models with coping appraisal as the explanatory factor most frequently contributing to the explanation of the variance in intentions showed strong discriminatory performance for staying home while not ill (mild outbreaks: Area under the curve [AUC] 0.85 (95% confidence interval 0.82;0.89), severe outbreaks AUC 0.82 (95% CI 0.77;0.85)) and acceptable performance with regard to avoiding public transportation (AUC 0.78 (0.74;0.82), AUC 0.77 (0.72;0.82)), using handwash products (AUC 0.70 (0.65;0.75), AUC 0.76 (0.71;0.80)), and frequently washing hands (AUC 0.71 (0.66;0.76), AUC 0.75 (0.71;0.80)). We conclude that coping appraisal was the explanatory factor most frequently included in statistical models explaining self-reported intentions to carry out non

Intentions to perform non-pharmaceutical protective behaviors during influenza outbreaks in Sweden: a cross-sectional study following a mass vaccination campaign.

Directory of Open Access Journals (Sweden)

Toomas Timpka

Full Text Available Failure to incorporate the beliefs and attitudes of the public into theoretical models of preparedness has been identified as a weakness in strategies to mitigate infectious disease outbreaks. We administered a cross-sectional telephone survey to a representative sample (n = 443 of the Swedish adult population to examine whether self-reported intentions to improve personal hygiene and increase social distancing during influenza outbreaks could be explained by trust in official information, self-reported health (SF-8, sociodemographic factors, and determinants postulated in protection motivation theory, namely threat appraisal and coping appraisal. The interviewees were asked to make their appraisals for two scenarios: a an influenza with low case fatality and mild lifestyle impact; b severe influenza with high case fatality and serious disturbances of societal functions. Every second respondent (50.0% reported high trust in official information about influenza. The proportion that reported intentions to take deliberate actions to improve personal hygiene during outbreaks ranged between 45-85%, while less than 25% said that they intended to increase social distancing. Multiple logistic regression models with coping appraisal as the explanatory factor most frequently contributing to the explanation of the variance in intentions showed strong discriminatory performance for staying home while not ill (mild outbreaks: Area under the curve [AUC] 0.85 (95% confidence interval 0.82;0.89, severe outbreaks AUC 0.82 (95% CI 0.77;0.85 and acceptable performance with regard to avoiding public transportation (AUC 0.78 (0.74;0.82, AUC 0.77 (0.72;0.82, using handwash products (AUC 0.70 (0.65;0.75, AUC 0.76 (0.71;0.80, and frequently washing hands (AUC 0.71 (0.66;0.76, AUC 0.75 (0.71;0.80. We conclude that coping appraisal was the explanatory factor most frequently included in statistical models explaining self-reported intentions to carry out non

Early-warning signals for an outbreak of the influenza pandemic

International Nuclear Information System (INIS)

Ren Di; Gao Jie

2011-01-01

Over the course of human history, influenza pandemics have been seen as major disasters, so studies on the influenza virus have become an important issue for many experts and scholars. Comprehensive research has been performed over the years on the biological properties, chemical characteristics, external environmental factors and other aspects of the virus, and some results have been achieved. Based on the chaos game representation walk model, this paper uses the time series analysis method to study the DNA sequences of the influenza virus from 1913 to 2010, and works out the early-warning signals indicator value for the outbreak of an influenza pandemic. The variances in the CGR walk sequences for the pandemic years (or + −1 to 2 years) are significantly higher than those for the adjacent years, while those in the non-pandemic years are usually smaller. In this way we can provide an influenza early-warning mechanism so that people can take precautions and be well prepared prior to a pandemic. (interdisciplinary physics and related areas of science and technology)

Global dynamic analysis of a H7N9 avian-human influenza model in an outbreak region.

Science.gov (United States)

Chen, Yongxue; Wen, Yongxian

2015-02-21

In 2013 in China a new type of avian influenza virus, H7N9, began to infect humans and had aroused severe fatality in the infected humans. We know that the spread is from poultry to humans, and the H7N9 avian influenza is low pathogenic in the poultry world but highly pathogenic in the human world, but the transmission mechanism is unclear. Since it has no signs of human-to-human transmission and outbreaks are isolated in some cities in China, in order to investigate the transmission mechanism of human infection with H7N9 avian influenza, an eco-epidemiological model in an outbreak region is proposed and analyzed dynamically. Researches and reports show that gene mutation makes the new virus be capable of infecting humans, therefore the mutation factor is taken into account in the model. The global dynamic analysis is conducted, different thresholds are identified, persistence and global qualitative behaviors are obtained. The impact of H7N9 avian influenza on the people population is concerned. Finally, the numerical simulations are carried out to support the theoretical analysis and to investigate the disease control measures. It seems that we may take people׳s hygiene and prevention awareness factor as a significant policy to achieve the aim of both the disease control and the economic returns. Copyright © 2014 Elsevier Ltd. All rights reserved.

Outbreak of avian influenza H7N3 on a turkey farm in the Netherlands

NARCIS (Netherlands)

Velkers, F.C.; Bouma, A.; Matthijs, M.G.R.; Koch, G.; Westendorp, S.T.; Stegeman, J.A.

2006-01-01

This case report describes the course of an outbreak of avian influenza on a Dutch turkey farm. When clinical signs were observed their cause remained unclear. However, serum samples taken for the monitoring campaign launched during the epidemic of highly pathogenic avian influenza in 2003, showed

A neighborhood susceptibility index for planning of local physical interventions in response to pandemic influenza outbreaks

Science.gov (United States)

Timpka, Toomas; Eriksson, Henrik; Strömgren, Magnus; Eriksson, Olle; Ekberg, Joakim; Grimvall, Anders; Nyce, James; Gursky, Elin; Holm, Einar

2010-01-01

The global spread of a novel A (H1N1) influenza virus in 2009 has highlighted the possibility of a devastating pandemic similar to the ‘Spanish flu’ of 1917–1918. Responding to such pandemics requires careful planning for the early phases where there is no availability of pandemic vaccine. We set out to compute a Neighborhood Influenza Susceptibility Index (NISI) describing the vulnerability of local communities of different geo-socio-physical structure to a pandemic influenza outbreak. We used a spatially explicit geo-physical model of Linköping municipality (pop. 136,240) in Sweden, and employed an ontology-modeling tool to define simulation models and transmission settings. We found considerable differences in NISI between neighborhoods corresponding to primary care areas with regard to early progress of the outbreak, as well as in terms of the total accumulated share of infected residents counted after the outbreak. The NISI can be used in local preparations of physical response measures during pandemics. PMID:21347087

Outbreak of avian influenza H7N3 on a turkey farm in the Netherlands.

Science.gov (United States)

Velkers, F C; Bouma, A; Matthijs, M G R; Koch, G; Westendorp, S T; Stegeman, J A

2006-09-23

This case report describes the course of an outbreak of avian influenza on a Dutch turkey farm. When clinical signs were observed their cause remained unclear. However, serum samples taken for the monitoring campaign launched during the epidemic of highly pathogenic avian influenza in 2003, showed that all the remaining turkeys were seropositive against an H7 strain of avian influenza virus, and the virus was subsequently isolated from stored carcases. The results of a reverse-transcriptase pcr showed that a H7N3 strain was involved, and it was characterised as of low pathogenicity. However, its intravenous pathogenicity index was 2.4, characterising it as of high pathogenicity, suggesting that a mixture of strains of low and high pathogenicity may have been present in the isolate. The outbreak remained limited to three farms.

Highlighting the complexities of a groundwater pilot study during an avian influenza outbreak: Methods, lessons learned, and select contaminant results

Science.gov (United States)

Hubbard, Laura E.; Kolpin, Dana W.; Fields, Chad L.; Hladik, Michelle L.; Iwanowicz, Luke

2017-01-01

The highly pathogenic avian influenza (H5N2) outbreak in the Midwestern United States (US) in 2015 was historic due to the number of birds and poultry operations impacted and the corresponding economic loss to the poultry industry and was the largest animal health emergency in US history. The U.S. Geological Survey (USGS), with the assistance of several state and federal agencies, aided the response to the outbreak by developing a study to determine the extent of virus transport in the environment. The study goals were to: develop the appropriate sampling methods and protocols for measuring avian influenza virus (AIV) in groundwater, provide the first baseline data on AIV and outbreak- and poultry-related contaminant occurrence and movement into groundwater, and document climatological factors that may have affected both survival and transport of AIV to groundwater during the months of the 2015 outbreak. While site selection was expedient, there were often delays in sample response times due to both relationship building between agencies, groups, and producers and logistical time constraints. This study's design and sampling process highlights the unpredictable nature of disease outbreaks and the corresponding difficulty in environmental sampling of such events. The lessons learned, including field protocols and approaches, can be used to improve future research on AIV in the environment.

Outbreak of pandemic influenza A/H1N1 2009 in Nepal.

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Adhikari, Bal Ram; Shakya, Geeta; Upadhyay, Bishnu Prasad; Prakash Kc, Khagendra; Shrestha, Sirjana Devi; Dhungana, Guna Raj

2011-03-23

The 2009 flu pandemic is a global outbreak of a new strain of H1N1 influenza virus. Pandemic influenza A (H1N1) 2009 has posed a serious public health challenge world-wide. Nepal has started Laboratory diagnosis of Pandemic influenza A/H1N1 from mid June 2009 though active screening of febrile travellers with respiratory symptoms was started from April 27, 2009. Out of 609 collected samples, 302 (49.6%) were Universal Influenza A positive. Among the influenza A positive samples, 172(28.3%) were positive for Pandemic influenza A/H1N1 and 130 (21.3%) were Seasonal influenza A. Most of the pandemic cases (53%) were found among young people with ≤ 20 years. Case Fatality Ratio for Pandemic influenza A/H1N1 in Nepal was 1.74%. Upon Molecular characterization, all the isolated pandemic influenza A/H1N1 2009 virus found in Nepal were antigenically and genetically related to the novel influenza A/CALIFORNIA/07/2009-LIKE (H1N1)v type. The Pandemic 2009 influenza virus found in Nepal were antigenically and genetically related to the novel A/CALIFORNIA/07/2009-LIKE (H1N1)v type.

Outbreak of pandemic influenza A/H1N1 2009 in Nepal

Directory of Open Access Journals (Sweden)

Shrestha Sirjana

2011-03-01

Full Text Available Abstract Background The 2009 flu pandemic is a global outbreak of a new strain of H1N1 influenza virus. Pandemic influenza A (H1N1 2009 has posed a serious public health challenge world-wide. Nepal has started Laboratory diagnosis of Pandemic influenza A/H1N1 from mid June 2009 though active screening of febrile travellers with respiratory symptoms was started from April 27, 2009. Results Out of 609 collected samples, 302 (49.6% were Universal Influenza A positive. Among the influenza A positive samples, 172(28.3% were positive for Pandemic influenza A/H1N1 and 130 (21.3% were Seasonal influenza A. Most of the pandemic cases (53% were found among young people with ≤ 20 years. Case Fatality Ratio for Pandemic influenza A/H1N1 in Nepal was 1.74%. Upon Molecular characterization, all the isolated pandemic influenza A/H1N1 2009 virus found in Nepal were antigenically and genetically related to the novel influenza A/CALIFORNIA/07/2009-LIKE (H1N1v type. Conclusion The Pandemic 2009 influenza virus found in Nepal were antigenically and genetically related to the novel A/CALIFORNIA/07/2009-LIKE (H1N1v type.

Avian influenza (bird flu) outbreak news scare and its economic ...

African Journals Online (AJOL)

Avian influenza (bird flu) outbreak news scare and its economic implication on poultry enterprises in Adamawa state, Nigeria. MR Ja'afar-Furo, HG Balla, B Yakubu. Abstract. No Abstract. Global Journal of Agricultural Sciences Vol. 6 (1) 2007: pp. 61-68. http://dx.doi.org/10.4314/gjass.v6i1.2302 · AJOL African Journals ...

Tracking socioeconomic vulnerability using network analysis: insights from an avian influenza outbreak in an ostrich production network.

Directory of Open Access Journals (Sweden)

Christine Moore

Full Text Available BACKGROUND: The focus of management in many complex systems is shifting towards facilitation, adaptation, building resilience, and reducing vulnerability. Resilience management requires the development and application of general heuristics and methods for tracking changes in both resilience and vulnerability. We explored the emergence of vulnerability in the South African domestic ostrich industry, an animal production system which typically involves 3-4 movements of each bird during its lifetime. This system has experienced several disease outbreaks, and the aim of this study was to investigate whether these movements have contributed to the vulnerability of this system to large disease outbreaks. METHODOLOGY/PRINCIPAL FINDINGS: The ostrich production system requires numerous movements of birds between different farm types associated with growth (i.e. Hatchery to juvenile rearing farm to adult rearing farm. We used 5 years of movement records between 2005 and 2011 prior to an outbreak of Highly Pathogenic Avian Influenza (H5N2. These data were analyzed using a network analysis in which the farms were represented as nodes and the movements of birds as links. We tested the hypothesis that increasing economic efficiency in the domestic ostrich industry in South Africa made the system more vulnerable to outbreak of Highly Pathogenic Avian Influenza (H5N2. Our results indicated that as time progressed, the network became increasingly vulnerable to pathogen outbreaks. The farms that became infected during the outbreak displayed network qualities, such as significantly higher connectivity and centrality, which predisposed them to be more vulnerable to disease outbreak. CONCLUSIONS/SIGNIFICANCE: Taken in the context of previous research, our results provide strong support for the application of network analysis to track vulnerability, while also providing useful practical implications for system monitoring and management.

Intentions to Perform Non-Pharmaceutical Protective Behaviors during Influenza Outbreaks in Sweden: A Cross-Sectional Study following a Mass Vaccination Campaign

Science.gov (United States)

Timpka, Toomas; Spreco, Armin; Gursky, Elin; Eriksson, Olle; Dahlström, Örjan; Strömgren, Magnus; Ekberg, Joakim; Pilemalm, Sofie; Karlsson, David; Hinkula, Jorma; Holm, Einar

2014-01-01

Failure to incorporate the beliefs and attitudes of the public into theoretical models of preparedness has been identified as a weakness in strategies to mitigate infectious disease outbreaks. We administered a cross-sectional telephone survey to a representative sample (n = 443) of the Swedish adult population to examine whether self-reported intentions to improve personal hygiene and increase social distancing during influenza outbreaks could be explained by trust in official information, self-reported health (SF-8), sociodemographic factors, and determinants postulated in protection motivation theory, namely threat appraisal and coping appraisal. The interviewees were asked to make their appraisals for two scenarios: a) an influenza with low case fatality and mild lifestyle impact; b) severe influenza with high case fatality and serious disturbances of societal functions. Every second respondent (50.0%) reported high trust in official information about influenza. The proportion that reported intentions to take deliberate actions to improve personal hygiene during outbreaks ranged between 45–85%, while less than 25% said that they intended to increase social distancing. Multiple logistic regression models with coping appraisal as the explanatory factor most frequently contributing to the explanation of the variance in intentions showed strong discriminatory performance for staying home while not ill (mild outbreaks: Area under the curve [AUC] 0.85 (95% confidence interval 0.82;0.89), severe outbreaks AUC 0.82 (95% CI 0.77;0.85)) and acceptable performance with regard to avoiding public transportation (AUC 0.78 (0.74;0.82), AUC 0.77 (0.72;0.82)), using handwash products (AUC 0.70 (0.65;0.75), AUC 0.76 (0.71;0.80)), and frequently washing hands (AUC 0.71 (0.66;0.76), AUC 0.75 (0.71;0.80)). We conclude that coping appraisal was the explanatory factor most frequently included in statistical models explaining self-reported intentions to carry out non

Influenza A outbreaks in Minnesota turkeys due to subtype H10N7 and possible transmission by waterfowl.

Science.gov (United States)

Karunakaran, D; Hinshaw, V; Poss, P; Newman, J; Halvorson, D

1983-01-01

Avian influenza outbreaks in Minnesota involving the H10N7 subtype occurred on two turkey farms in 1979 and on a third in 1980. The H10N7 (Hav2 Neq1) subtype had not previously been detected in turkeys in Minnesota or reported in the United States. The clinical signs ranged from severe, with a mortality rate as high as 31%, to subclinical. Antigenically indistinguishable viruses were isolated from healthy mallards on a pond adjacent to the turkey farms, suggesting that the virus responsible for the outbreak may have been introduced by feral ducks.

Control of H1N1 influenza outbreak: A study conducted in a naval warship

Directory of Open Access Journals (Sweden)

Arun Gupta

2017-01-01

Full Text Available Introduction: In confined afloat settings, the threat of an acceleration of the Influenza outbreak is substantial, causing high morbidity of the personnel on board, disrupting daily activities, and leading to low crew morale. In this study, H1N1 Influenza outbreak in a Naval Warship and its control measures are described. Materials and Methods: It is a study of 21 clinically suspected cases of H1N1 Influenza. Cases were reported within 3 weeks from a ship company, all of whom were susceptible. They have been described on the basis of demography, clinical features, recent travel history, and history of contact. Results: Mean age of the clinically suspected cases was 26.71 years. Of 21 suspected cases, 14 were found positive for the disease. Nine cases were admitted to the hospital and two developed complications. Attack rate of the disease was 4.83%. Conclusion: In confined afloat settings, prompt public health measures of active case finding, strict isolation, and adherence to hand hygiene, following cough etiquettes and disinfection enhancement, can effectively mitigate the outbreak. Vaccination may not have a role to play if preventive measures are instituted effectively.

Outbreak of avian influenza H7N3 on a turkey farm in the Netherlands

OpenAIRE

Velkers, F.C.; Bouma, A.; Matthijs, M.G.R.; Koch, G.; Westendorp, S.T.; Stegeman, J.A.

2006-01-01

This case report describes the course of an outbreak of avian influenza on a Dutch turkey farm. When clinical signs were observed their cause remained unclear. However, serum samples taken for the monitoring campaign launched during the epidemic of highly pathogenic avian influenza in 2003, showed that all the remaining turkeys were seropositive against an H7 strain of avian influenza virus, and the virus was subsequently isolated from stored carcases. The results of a reverse-transcriptase P...

Controlling highly pathogenic avian influenza outbreaks : An epidemiological and economic model analysis

NARCIS (Netherlands)

Backer, J. A.; van Roermund, H. J W; Fischer, Egil; van Asseldonk, M. A P M; Bergevoet, R. H M

2015-01-01

Outbreaks of highly pathogenic avian influenza (HPAI) can cause large losses for the poultry sector and for animal disease controlling authorities, as well as risks for animal and human welfare. In the current simulation approach epidemiological and economic models are combined to compare different

Highlighting the complexities of a groundwater pilot study during an avian influenza outbreak: Methods, lessons learned, and select contaminant results.

Science.gov (United States)

Hubbard, Laura E; Kolpin, Dana W; Fields, Chad L; Hladik, Michelle L; Iwanowicz, Luke R

2017-10-01

The highly pathogenic avian influenza (H5N2) outbreak in the Midwestern United States (US) in 2015 was historic due to the number of birds and poultry operations impacted and the corresponding economic loss to the poultry industry and was the largest animal health emergency in US history. The U.S. Geological Survey (USGS), with the assistance of several state and federal agencies, aided the response to the outbreak by developing a study to determine the extent of virus transport in the environment. The study goals were to: develop the appropriate sampling methods and protocols for measuring avian influenza virus (AIV) in groundwater, provide the first baseline data on AIV and outbreak- and poultry-related contaminant occurrence and movement into groundwater, and document climatological factors that may have affected both survival and transport of AIV to groundwater during the months of the 2015 outbreak. While site selection was expedient, there were often delays in sample response times due to both relationship building between agencies, groups, and producers and logistical time constraints. This study's design and sampling process highlights the unpredictable nature of disease outbreaks and the corresponding difficulty in environmental sampling of such events. The lessons learned, including field protocols and approaches, can be used to improve future research on AIV in the environment. Published by Elsevier Inc.

Outbreaks of health care-associated influenza-like illness in France: Impact of electronic notification.

Science.gov (United States)

Munier-Marion, Elodie; Bénet, Thomas; Dananché, Cédric; Soing-Altach, Sophan; Maugat, Sylvie; Vaux, Sophie; Vanhems, Philippe

2017-11-01

Mandatory notification of health care-associated (HA) infections, including influenza-like illness (ILI) outbreaks, has been implemented in France since 2001. In 2012, the system moved to online electronic notification of HA infections (e-SIN). The objectives of this study are to describe ILI outbreak notifications to Santé publique France (SPF), the French national public health agency, and to evaluate the impact of notification dematerialization. All notifications of HA ILI outbreaks between July 2001 and June 2015 were included. Notifications before and after e-SIN implementation were compared regarding notification delay and information exhaustiveness. Overall, 506 HA ILI outbreaks were reported, accounting for 7,861 patients and health care professionals. Median delay between occurrence of the first case and notification was, respectively, 32 and 13 days before and after e-SIN utilization (P < .001). Information exhaustiveness was improved by electronic notification regarding HA status (8.5% of missing data before and 2.3% after e-SIN, P = .003), hypotheses of cause (25.4% of missing data before vs 8.0% after e-SIN, P < .001), and level of event control (23.7% of missing data before vs 7.5% after e-SIN, P < .001). HA influenza notifications, including HA ILI or influenza, to health authorities are essential to guide decisional instances and health care practices. Electronic notifications have improved the timeliness and quality of information transmitted. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Outbreak of 2009 pandemic influenza A(H1N1), Los Lagos, Chile, April-June 2009.

Science.gov (United States)

Pedroni, E; Garcia, M; Espinola, V; Guerrero, A; Gonzalez, C; Olea, A; Calvo, M; Martorell, B; Winkler, M; Carrasco, Mv; Vergara, Ja; Ulloa, J; Carrazana, Am; Mujica, O; Villarroel, Je; Labrana, M; Vargas, M; Gonzalez, P; Caceres, L; Zamorano, Cg; Momberg, R; Munoz, G; Rocco, J; Bosque, V; Gallardo, A; Elgueta, J; Vega, J

2010-01-07

On 17 May 2009, the first two cases of 2009 pandemic influenza A(H1N1) were confirmed in the Metropolitan region (Santiago, Chile). On 6 June 2009, Chile reported 500 confirmed cases, seven severe and two fatal. Because six of the severe cases and the two deaths occurred in the region of Los Lagos in southern Chile, a retrospective study was conducted using data on emergency room visits as well as laboratory viral surveillance, during the period from 1 April to 31 May, in order to establish the date of the beginning of the outbreak. From 1 to 27 June, data were collected in real time, to establish the real magnitude of the outbreak, describe its transmission, clinical severity and secondary attack rates. Confirmed cases, their household contacts and healthcare workers were interviewed. This analysis showed that the outbreak in Los Lagos started on 28 April. By 27 June, a total of 14.559 clinical cases were identified, affecting mostly 5-19 year-olds. The effective reproduction number during the initial phase (20 days) was 1.8 (1.6-2.0). Of the 190 confirmed cases with severe acute respiratory infection, 71 (37.4%) presented a risk condition or underlying illness.

Estimating Influenza Outbreaks Using Both Search Engine Query Data and Social Media Data in South Korea.

Science.gov (United States)

Woo, Hyekyung; Cho, Youngtae; Shim, Eunyoung; Lee, Jong-Koo; Lee, Chang-Gun; Kim, Seong Hwan

2016-07-04

As suggested as early as in 2006, logs of queries submitted to search engines seeking information could be a source for detection of emerging influenza epidemics if changes in the volume of search queries are monitored (infodemiology). However, selecting queries that are most likely to be associated with influenza epidemics is a particular challenge when it comes to generating better predictions. In this study, we describe a methodological extension for detecting influenza outbreaks using search query data; we provide a new approach for query selection through the exploration of contextual information gleaned from social media data. Additionally, we evaluate whether it is possible to use these queries for monitoring and predicting influenza epidemics in South Korea. Our study was based on freely available weekly influenza incidence data and query data originating from the search engine on the Korean website Daum between April 3, 2011 and April 5, 2014. To select queries related to influenza epidemics, several approaches were applied: (1) exploring influenza-related words in social media data, (2) identifying the chief concerns related to influenza, and (3) using Web query recommendations. Optimal feature selection by least absolute shrinkage and selection operator (Lasso) and support vector machine for regression (SVR) were used to construct a model predicting influenza epidemics. In total, 146 queries related to influenza were generated through our initial query selection approach. A considerable proportion of optimal features for final models were derived from queries with reference to the social media data. The SVR model performed well: the prediction values were highly correlated with the recent observed influenza-like illness (r=.956; Psearch queries to enhance influenza surveillance in South Korea. In addition, an approach for query selection using social media data seems ideal for supporting influenza surveillance based on search query data.

Statistics of severe tornadoes and severe tornado outbreaks

Directory of Open Access Journals (Sweden)

B. D. Malamud

2012-09-01

Full Text Available The standard measures of the intensity of a tornado in the USA and many other countries are the Fujita and Enhanced Fujita scales. These scales are based on the damage that a tornado causes. Another measure of the strength of a tornado is its path length of touchdown, L. In this study we consider severe tornadoes, which we define as L≥10 km, in the continental USA (USA Storm Prediction Center Severe Weather Database. We find that for the period 1982–2011, for individual severe tornadoes (L≥10 km: (i There is a strong linear scaling between the number of severe tornadoes in a year and their total path length in that year. (ii The cumulative frequency path length data suggests that, not taking into account any changing trends over time, we would expect in a given year (on average one severe tornado with a path length L≥115 km and in a decade (on average one severe tornado with a path length L≥215 km. (iii The noncumulative frequency-length statistics of severe tornado touchdown path lengths, 20<L<200 km, is well approximated by an inverse power-law relationship with exponent near 3. We then take the total path length of severe tornadoes in a convective day (12:00–12:00 UTC, L_D, as a measure of the strength of a 24-h USA tornado outbreak. We find that: (i For 1982–2011, the number of severe tornadoes in a USA convective day outbreak has a strong power-law relationship (exponent 0.80 on the convective day total path length, L_D. (ii For 1952–2011, the cumulative frequency path length data for severe tornado outbreaks suggests that we would expect in a given year (on average one daily severe tornado outbreak with total path length L_D≥480 km and in a decade (on average one daily severe tornado outbreak with a total path length L_D≥1200 km. (iii For 1982–2011, the noncumulative frequency-length statistics of tornado

The role of rodents in avian influenza outbreaks in poultry farms : a review

NARCIS (Netherlands)

Velkers, Francisca C; Blokhuis, Simon J; Veldhuis Kroeze, Edwin J B; Burt, Sara A

2017-01-01

Wild migratory birds are associated with global avian influenza virus (AIV) spread. Although direct contact with wild birds and contaminated fomites is unlikely in modern non-free range poultry farms applying biosecurity measures, AIV outbreaks still occur. This suggests involvement of other

Nowcasting influenza outbreaks using open-source media report.

Energy Technology Data Exchange (ETDEWEB)

Ray, Jaideep; Brownstein, John S. [Boston Children%3CU%2B2019%3Es Hospital, Boston, MA

2013-02-01

We construct and verify a statistical method to nowcast influenza activity from a time-series of the frequency of reports concerning influenza related topics. Such reports are published electronically by both public health organizations as well as newspapers/media sources, and thus can be harvested easily via web crawlers. Since media reports are timely, whereas reports from public health organization are delayed by at least two weeks, using timely, open-source data to compensate for the lag in %E2%80%9Cofficial%E2%80%9D reports can be useful. We use morbidity data from networks of sentinel physicians (both the Center of Disease Control's ILINet and France's Sentinelles network) as the gold standard of influenza-like illness (ILI) activity. The time-series of media reports is obtained from HealthMap (http://healthmap.org). We find that the time-series of media reports shows some correlation ( 0.5) with ILI activity; further, this can be leveraged into an autoregressive moving average model with exogenous inputs (ARMAX model) to nowcast ILI activity. We find that the ARMAX models have more predictive skill compared to autoregressive (AR) models fitted to ILI data i.e., it is possible to exploit the information content in the open-source data. We also find that when the open-source data are non-informative, the ARMAX models reproduce the performance of AR models. The statistical models are tested on data from the 2009 swine-flu outbreak as well as the mild 2011-2012 influenza season in the U.S.A.

Influenza A(H10N7) Virus in Dead Harbor Seals, Denmark

DEFF Research Database (Denmark)

Krog, Jesper Schak; Hansen, Mette Sif; Holm, Elisabeth

2015-01-01

Since April 2014, an outbreak of influenza in harbor seals has been ongoing in northern Europe. In Denmark during June-August, 152 harbor seals on the island of Anholt were found dead from severe pneumonia. We detected influenza A(H10N7) virus in 2 of 4 seals examined.......Since April 2014, an outbreak of influenza in harbor seals has been ongoing in northern Europe. In Denmark during June-August, 152 harbor seals on the island of Anholt were found dead from severe pneumonia. We detected influenza A(H10N7) virus in 2 of 4 seals examined....

Protective measures and human antibody response during an avian influenza H7N3 outbreak in poultry in British Columbia, Canada.

Science.gov (United States)

Skowronski, Danuta M; Li, Yan; Tweed, S Aleina; Tam, Theresa W S; Petric, Martin; David, Samara T; Marra, Fawziah; Bastien, Nathalie; Lee, Sandra W; Krajden, Mel; Brunham, Robert C

2007-01-02

In 2004 an outbreak of avian influenza of the H7N3 subtype occurred among poultry in British Columbia, Canada. We report compliance with recommended protective measures and associated human infections during this outbreak. We sought voluntary participation by anyone (cullers, farmers and their families) involved in efforts to control the poultry outbreak. Recruitment was by advertisements at the worker deployment site, in local media and through newsletters sent directly to farmers. Sera were tested for antibody to H7N3 by microneutralization assay. A subset of 16 sera (including convalescent sera from 2 unprotected workers with conjunctivitis from whom virus had been isolated) was further tested by Western blot and routine and modified hemagglutination inhibition assays. A total of 167 people (20% to 25% of all workers) participated between May 7 and July 26, 2004. Of these, 19 had experienced influenza-like illness and 21 had experienced red or watery eyes. There was no significant association between illness reports and exposure to infected birds. Among 65 people who entered barns with infected birds, 55 (85%) had received influenza vaccine, 48 (74%) had received oseltamivir, and 55 (85%), 54 (83%) and 36 (55%) reported always wearing gloves, mask or goggles, respectively. Antibody to the H7 subtype was not detected in any sera. During the BC outbreak, compliance with recommended protective measures, especially goggles, was incomplete. Multiple back-up precautions, including oseltamivir prophylaxis, may prevent human infections and should be readily accessible and consistently used by those involved in the control of future outbreaks of avian influenza in poultry. Localized human avian influenza infections may not result in serologic response despite confirmed viral detection and culture.

Late diagnosis of influenza in adult patients during a seasonal outbreak.

Science.gov (United States)

Choi, Seong-Ho; Chung, Jin-Won; Kim, Tark; Park, Ki-Ho; Lee, Mi Suk; Kwak, Yee Gyung

2018-03-01

Due to advances in diagnostic techniques, clinicians are more frequently performing influenza diagnostic tests and referring to their test results ahead of the administration of neuraminidase inhibitors (NAIs). To investigate the clinical significance of the time from symptom onset to laboratory diagnosis, we reviewed the clinical characteristics of adult patients with influenza who had an early laboratory diagnosis (ED) or a late laboratory diagnosis (LD) at one of four tertiary care centers during a seasonal outbreak of influenza. Clinical data were collected from 1,405 adults during the 2013 to 2014 influenza season. A patient was regarded as receiving an ED or LD if he/she received an influenza diagnostic test at 0 to 1 or 4 to 7 days after symptom onset, respectively. Early NAI therapy and late NAI therapy were defined as the administration of NAI ≤ 2 or > 2 days after symptom onset, respectively. Nearly half of the patients (47.0%) received an ED (n = 661), whereas 13.5% (n = 190) received a LD. Patients with a LD had initial symptoms of cough, sputum production, and dyspnea and experienced pneumonia, antibiotic therapy, hospitalization, and admission to the intensive care unit more often than those with an ED. NAI therapy and early NAI therapy were less frequent in patients with a LD than those with an ED. Of the analyzed baseline characteristics, age ≥ 50 years, influenza B infection, and diagnosis using a polymerase chain reaction test were significantly associated with a LD. LD was associated with inappropriate antiviral therapy and complicated presenting features in adult patients with seasonal influenza. ED of influenza should be emphasized, especially for older adults.

Risk factors and clusters of Highly Pathogenic Avian Influenza H5N1 outbreaks in Bangladesh

Science.gov (United States)

Loth, Leo; Gilbert, Marius; Osmani, Mozaffar G.; Kalam, Abul M.; Xiao, Xiangming

2016-01-01

Between March 2007 and July 2009, 325 Highly Pathogenic Avian Influenza (HPAI, subtype H5N1) outbreaks in poultry were reported in 154 out of a total of 486 sub-districts in Bangladesh. This study analyzed the temporal and spatial patterns of HPAI H5N1 outbreaks and quantified the relationship between several spatial risk factors and HPAI outbreaks in sub-districts in Bangladesh. We assessed spatial autocorrelation and spatial dependence, and identified clustering sub-districts with disease statistically similar to or dissimilar from their neighbors. Three significant risk factors associated to HPAI H5N1 virus outbreaks were identified; the quadratic log-transformation of human population density [humans per square kilometer, P = 0.01, OR 1.15 (95% CI: 1.03–1.28)], the log-transformation of the total commercial poultry population [number of commercial poultry per sub-district, P Bangladesh to target surveillance and to concentrate response efforts in areas where disease is likely to occur. Concentrating response efforts may help to combat HPAI more effectively, reducing the environmental viral load and so reducing the number of disease incidents. PMID:20554337

Deaths among wild birds during highly pathogenic avian influenza A(H5N8) virus outbreak, the Netherlands

NARCIS (Netherlands)

Kleyheeg, Erik; Slaterus, Roy; Bodewes, Rogier; Rijks, Jolianne M.; Spierenburg, Marcel A.H.; Beerens, Nancy; Kelder, Leon; Poen, Marjolein J.; Stegeman, Jan A.; Fouchier, Ron A.M.; Kuiken, Thijs; Jeugd, van der Henk P.

2017-01-01

During autumn–winter 2016–2017, highly pathogenic avian influenza A(H5N8) viruses caused mass die-offs among wild birds in the Netherlands. Among the ≈13,600 birds reported dead, most were tufted ducks (Aythya fuligula) and Eurasian wigeons (Anas penelope). Recurrence of avian influenza outbreaks

Deaths among Wild Birds during Highly Pathogenic Avian Influenza A(H5N8) Virus Outbreak, the Netherlands

NARCIS (Netherlands)

Kleyheeg, Erik; Slaterus, Roy; Bodewes, Rogier; Rijks, Jolianne M.; Spierenburg, Marcel A.H.; Beerens, Nancy; Kelder, Leon; Poen, Marjolein J.; Stegeman, Jan A.; Fouchier, Ron A. M.; Kuiken, Thijs; Jeugd, Henk P. van der

2017-01-01

During autumn–winter 2016–2017, highly pathogenic avian influenza A(H5N8) viruses caused mass die-offs among wild birds in the Netherlands. Among the ≈13,600 birds reported dead, most were tufted ducks (Aythya fuligula) and Eurasian wigeons (Anas penelope). Recurrence of avian influenza outbreaks

The ecology and age structure of a highly pathogenic avian influenza virus outbreak in wild mute swans.

Science.gov (United States)

Pybus, O G; Perrins, C M; Choudhury, B; Manvell, R J; Nunez, A; Schulenburg, B; Sheldon, B C; Brown, I H

2012-12-01

The first UK epizootic of highly pathogenic (HP) H5N1 influenza in wild birds occurred in 2008, in a population of mute swans that had been the subject of ornithological study for decades. Here we use an innovative combination of ornithological, phylogenetic and immunological approaches to investigate the ecology and age structure of HP H5N1 in nature. We screened samples from swans and waterbirds using PCR and sequenced HP H5N1-positive samples. The outbreak's origin was investigated by linking bird count data with a molecular clock analysis of sampled virus sequences. We used ringing records to reconstruct the age-structure of outbreak mortality, and we estimated the age distribution of prior exposure to avian influenza. Outbreak mortality was low and all HP H5N1-positive mute swans in the affected population were <3 years old. Only the youngest age classes contained an appreciable number of individuals with no detectable antibody responses to viral nucleoprotein. Phylogenetic analysis indicated that the outbreak strain circulated locally for ~1 month before detection and arrived when the immigration rate of migrant waterbirds was highest. Our data are consistent with the hypothesis that HP H5N1 epizootics in wild swans exhibit limited mortality due to immune protection arising from previous exposure. Our study population may represent a valuable resource for investigating the natural ecology and epidemiology of avian influenza.

Characterization of influenza A(H1N1)pdm09 viruses isolated from Nepalese and Indian outbreak patients in early 2015.

Science.gov (United States)

Nakamura, Kazuya; Shirakura, Masayuki; Fujisaki, Seiichiro; Kishida, Noriko; Burke, David F; Smith, Derek J; Kuwahara, Tomoko; Takashita, Emi; Takayama, Ikuyo; Nakauchi, Mina; Chadha, Mandeep; Potdar, Varsha; Bhushan, Arvind; Upadhyay, Bishnu Prasad; Shakya, Geeta; Odagiri, Takato; Kageyama, Tsutomu; Watanabe, Shinji

2017-09-01

We characterized influenza A(H1N1)pdm09 isolates from large-scale outbreaks that occurred in Nepal and India in early 2015. Although no specific viral features, which may have caused the outbreaks, were identified, an S84N substitution in hemagglutinin was frequently observed. Chronological phylogenetic analysis revealed that these Nepalese and Indian viruses possessing the S84N substitution constitute potential ancestors of the novel genetic subclade 6B.1 virus that spread globally in the following (2015/16) influenza season. Thus, active surveillance of circulating influenza viruses in the Southern Asia region, including Nepal and India, would be beneficial for detecting novel variant viruses prior to their worldwide spread. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Evaluating the effects of common control measures for influenza A (H1N1 outbreak at school in China: A modeling study.

Directory of Open Access Journals (Sweden)

Tianmu Chen

Full Text Available Influenza A (H1N1 outbreaks have become common at schools in China since 2009. However, the effects of common countermeasures for school influenza outbreak have not been quantified so far, including isolation, vaccination, antivirus and school closure. We conducted a mathematically modeling study to address this unsolved issue.We collected data of all small-scale school outbreaks caused by influenza A that occurred in Changsha city between January 2009 and December 2013. Two outbreaks (one was in 2009 and the other one was in 2013 were used for simulating the effects of single and combined use of common measures, including isolation (Iso, therapeutics (T, prophylactics (P, vaccinating 70% of susceptible individuals prior to the outbreak (VP70, vaccinating 70% of susceptible individuals every day during the outbreak (VD70 and school closure of one week (S1w. A susceptible-exposed-infectious/asymptomatic-recovered (SEIR model was developed to implement the simulations based on the natural history of influenza A.When no control measures are taken, the influenza is expected to spread quickly at school for the selected outbreak in 2013; the outbreak would last 56 days, and the total attack rate (TAR would reach up to 46.32% (95% CI: 46.12-46.52. Of all single control measures, VP70 is most effective to control the epidemic (TAR = 8.68%, followed by VP50, VD70, VD50 and Iso. The use of VP70 with any other measure can reduce TAR to 3.37-14.04% and showed better effects than any other combination of two kinds of measures. The best two-measure combination is 'S1w+VP70' (TAR = 3.37%, DO = 41 days. All combinations of three kinds of measures were not satisfactory when Vp70 and VD70 were excluded. The most effective three-intervention combination was 'Iso+S1w+VP70' (with TAR = 3.23%. When VP70 or VD70 is included, the combinations of four or five kinds of interventions are very effective, reducing TAR to lower than 5%. But the TAR of combination of 'T

Universal Detection and Identification of Avian Influenza Virus by Use of Resequencing Microarrays

Science.gov (United States)

2009-04-01

Recent outbreaks of Nipah virus , severe acute respiratory syndrome virus , and avian influenza virus reiterate the impor- tance of zoonotic microbes as...Society for Microbiology. All Rights Reserved. Universal Detection and Identification of Avian Influenza Virus by Use of Resequencing Microarrays...been, and continue to emerge as, threats to human health. The recent outbreaks of highly pathogenic avian influenza virus in bird populations and the

Assessment of farm-level biosecurity measures after an outbreak of avian influenza in the United Kingdom.

Science.gov (United States)

Knight-Jones, T J D; Gibbens, J; Wooldridge, M; Stärk, K D C

2011-02-01

During Avian Influenza outbreaks in England, the 'AI Order' states that a poultry keeper may be required to keep domestic birds separate from wild birds. This study aimed to assess a) how effectively this was done and b) the negative impact this had for bird owners and animal welfare during the November 2007 Highly Pathogenic Avian Influenza (HPAI) outbreak in Suffolk, UK. A voluntary questionnaire was posted to holdings (n=296) that were within 10 km of an infected premises; these holdings were required to separate domestic and wild birds where possible. Holdings were identified during outbreak investigations conducted by the authorities. Holdings of all sizes were included. A sample of holdings received a follow-up visit or telephone call to validate the questionnaire (n=29). From the 38% of eligible holdings that responded, 13% (95% CI 7-22%) left their birds outdoors throughout the outbreak. If game birds were excluded, 9% (CI 4-17%) of holdings did not house their birds. Major cost and welfare problems were rare; however, there were exceptions. Enforced housing was often relaxed before a minor welfare problem deteriorated. Contact between wild and domestic birds was greatly reduced during the outbreak, resulting in a reduced probability of HPAI transmission via wild birds for most, but not all, holdings. © 2010 Blackwell Verlag GmbH.

Disease Outbreak News

Science.gov (United States)

... MERS-CoV) Pandemic (H1N1) 2009 Influenza at the Human-Animal Interface (HAI) Related documents WHO outbreak communication guide 2008 WHO outbreak communications guidelines Outbreak communication: ...

Isolation and characterization of virus of highly pathogenic avian influenza H5 subtype of chicken from outbreaks in Indonesia

Directory of Open Access Journals (Sweden)

Agus Wiyono

2004-03-01

Full Text Available A study on the isolation and characterization of Highly Pathogenic Avian Influenza of chicken from outbreaks in Indonesia was conducted at Indonesian Research Institute for Veterinary Science. Outbreaks of avian disease had been reported in Indonesia since August 2003 affecting commercial layer, broiler, quail, and ostrich and also native chicken with showing clinical signs such as cyanosis of wattle and comb, nasal discharges and hypersalivation, subcutaneous ptechiae on foot and leg, diarre and sudden high mortality. The aim of this study is to isolate and characterize the causal agent of the disease. Samples of serum, feather follicle, tracheal swab, as well as organs of proventriculus, intestine, caecal tonsil, trachea and lungs were collected from infected animals. Serum samples were tested haemaglutination/haemaglutination inhibition to Newcastle Disease and Egg Drop Syndrome viruses. Isolation of virus of the causal agent of the outbreak was conducted from samples of feather follicle, tracheal swab, and organs using 11 days old specific pathogen free (SPF embryonated eggs. The isolated viruses were then characterised by agar gel precipitation test using swine influenza reference antisera, by haemaglutination inhibition using H1 to H15 reference antisera, and by electron microscope examination. The pathogenicity of the viruses was confirmed by intravenous pathogenicity index test and its culture in Chicken Embryo Fibroblast primary cell culture without addition of trypsin. The study revealed that the causative agent of the outbreaks of avian disease in Indonesia was avian influenza H5 subtype virus based upon serological tests, virus isolation and characterization using swine influenza reference antisera, and electron microscope examination. While subtyping of the viruses using H1 to H15 reference antisera suggested that the virus is very likely to be an avian influenza H5N1 subtype virus. The pathogenicity test confirmed that the viruses

Transmission of equine influenza virus during an outbreak is characterized by frequent mixed infections and loose transmission bottlenecks.

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Joseph Hughes

2012-12-01

Full Text Available The ability of influenza A viruses (IAVs to cross species barriers and evade host immunity is a major public health concern. Studies on the phylodynamics of IAVs across different scales - from the individual to the population - are essential for devising effective measures to predict, prevent or contain influenza emergence. Understanding how IAVs spread and evolve during outbreaks is critical for the management of epidemics. Reconstructing the transmission network during a single outbreak by sampling viral genetic data in time and space can generate insights about these processes. Here, we obtained intra-host viral sequence data from horses infected with equine influenza virus (EIV to reconstruct the spread of EIV during a large outbreak. To this end, we analyzed within-host viral populations from sequences covering 90% of the infected yards. By combining gene sequence analyses with epidemiological data, we inferred a plausible transmission network, in turn enabling the comparison of transmission patterns during the course of the outbreak and revealing important epidemiological features that were not apparent using either approach alone. The EIV populations displayed high levels of genetic diversity, and in many cases we observed distinct viral populations containing a dominant variant and a number of related minor variants that were transmitted between infectious horses. In addition, we found evidence of frequent mixed infections and loose transmission bottlenecks in these naturally occurring populations. These frequent mixed infections likely influence the size of epidemics.

Influenza risk management: lessons learned from an A(H1N1) pdm09 outbreak investigation in an operational military setting.

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Farrell, Margaret; Sebeny, Peter; Klena, John D; Demattos, Cecilia; Pimentel, Guillermo; Turner, Mark; Joseph, Antony; Espiritu, Jennifer; Zumwalt, John; Dueger, Erica

2013-01-01

At the onset of an influenza pandemic, when the severity of a novel strain is still undetermined and there is a threat of introduction into a new environment, e.g., via the deployment of military troops, sensitive screening criteria and conservative isolation practices are generally recommended. In response to elevated rates of influenza-like illness among U.S. military base camps in Kuwait, U.S. Naval Medical Research Unit No. 3 partnered with local U.S. Army medical units to conduct an A(H1N1) pdm09 outbreak investigation. Initial clinical data and nasal specimens were collected via the existent passive surveillance system and active surveillance was conducted using a modified version of the World Health Organization/U.S. Centers for Disease Control and Prevention influenza-like illness case definition [fever (T > 100.5˚F/38˚C) in addition to cough and/or sore throat in the previous 72 hours] as the screening criteria. Samples were tested via real-time reverse-transcription PCR and sequenced for comparison to global A(H1N1) pdm09 viruses from the same time period. The screening criteria used in Kuwait proved insensitive, capturing only 16% of A(H1N1) pdm09-positive individuals. While still not ideal, using cough as the sole screening criteria would have increased sensitivity to 73%. The results of and lessons learned from this outbreak investigation suggest that pandemic influenza risk management should be a dynamic process (as information becomes available regarding true attack rates and associated mortality, screening and isolation criteria should be re-evaluated and revised as appropriate), and that military operational environments present unique challenges to influenza surveillance.

Variable epidemiology of the three outbreaks of unrelated highly pathogenic avian influenza viruses in the United States, 2014-2017

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Three unrelated highly pathogenic avian influenza (HPAI) outbreaks have occurred in the United States (US) during 2014-2017. Late in 2014, Canada reported the first outbreak of an H5N2 reassortment virus between the A/goose/Guangdong/1/1996 (Gs/GD)-lineage H5Nx clade 2.3.4.4A HPAI and North American...

High morbidity and mortality associated with an outbreak of influenza A(H3N2) in a psycho-geriatric facility.

LENUS (Irish Health Repository)

Sayers, G

2012-04-17

SUMMARYIn spring 2008, an influenza A subtype H3N2 outbreak occurred in a long stay psycho-geriatric ward and two wards in the intellectual disability services (IDS), part of a large psychiatric hospital. The attack rate in the index ward was 90% (18\\/20) for patients and 35% (7\\/20) for staff. It was 14% (1\\/7) and 17% (2\\/12) in the affected IDS wards for patients and 0% (0\\/20) and 4% (1\\/25) for staff. Many of the laboratory-confirmed cases did not have a fever >38°C, a typical sign of influenza. Control measures included oseltamivir treatment for cases and prophylaxis for contacts, standard and droplet infection control precautions, active surveillance for early detection and isolation of potential cases. As a result, the outbreak did not spread throughout the hospital. Although the staff vaccination rate (10%) prior to the outbreak was low, we observed a much lower vaccine effectiveness rate in the patients (11%) than in the staff (100%) in the index ward. Vaccination of residents and staff of such facilities remains the key influenza prevention strategy.

Pandemic influenza A(H1N1) outbreak among a group of medical students who traveled to the Dominican Republic.

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Vilella, Anna; Serrano, Beatriz; Marcos, Maria A; Serradesanferm, Anna; Mensa, Josep; Hayes, Edward; Anton, Andres; Rios, Jose; Pumarola, Tomas; Trilla, Antoni

2012-01-01

From the beginning of the influenza pandemic until the time the outbreak described here was detected, 77,201 cases of pandemic influenza A(H1N1) with 332 deaths had been reported worldwide, mostly in the United States and Mexico. All of the cases reported in Spain until then had a recent history of travel to Mexico, the Dominican Republic, or Chile. We describe an outbreak of influenza among medical students who traveled from Spain to the Dominican Republic in June 2009. We collected diagnostic samples and clinical histories from consenting medical students who had traveled to the Dominican Republic and from their household contacts after their return to Spain. Of 113 students on the trip, 62 (55%) developed symptoms; 39 (45%) of 86 students tested had laboratory evidence of influenza A(H1N1) infection. Most students developed symptoms either just before departure from the Dominican Republic or within days of returning to Spain. The estimated secondary attack rate of influenza-like illness among residential contacts of ill students after return to Spain was 2.1%. The attack rate of influenza A(H1N1) can vary widely depending on the circumstances of exposure. We report a high attack rate among a group of traveling medical students but a much lower secondary attack rate among their contacts after return from the trip. These findings may aid the development of recommendations to prevent influenza. © 2011 International Society of Travel Medicine.

Outbreak of H3N2 influenza at a US military base in Djibouti during the H1N1 pandemic of 2009.

Science.gov (United States)

Cosby, Michael T; Pimentel, Guillermo; Nevin, Remington L; Fouad Ahmed, Salwa; Klena, John D; Amir, Ehab; Younan, Mary; Browning, Robert; Sebeny, Peter J

2013-01-01

Influenza pandemics have significant operational impact on deployed military personnel working in areas throughout the world. The US Department of Defense global influenza-like illness (ILI) surveillance network serves an important role in establishing baseline trends and can be leveraged to respond to outbreaks of respiratory illness. We identified and characterized an operationally unique outbreak of H3N2 influenza at Camp Lemonnier, Djibouti occurring simultaneously with the H1N1 pandemic of 2009 [A(H1N1)pdm09]. Enhanced surveillance for ILI was conducted at Camp Lemonnier in response to local reports of a possible outbreak during the A(H1N1)pdm09 pandemic. Samples were collected from consenting patients presenting with ILI (utilizing a modified case definition) and who completed a case report form. Samples were cultured and analyzed using standard real-time reverse transcriptase PCR (rt-RT-PCR) methodology and sequenced genetic material was phylogenetically compared to other published strains. rt-RT-PCR and DNA sequencing revealed that 25 (78%) of the 32 clinical samples collected were seasonal H3N2 and only 2 (6%) were A(H1N1)pdm09 influenza. The highest incidence of H3N2 occurred during the month of May and 80% of these were active duty military personnel. Phylogenetic analysis revealed that sequenced H3N2 strains were genetically similar to 2009 strains from the United States of America, Australia, and South east Asia. This outbreak highlights challenges in the investigation of influenza among deployed military populations and corroborates the public health importance of maintaining surveillance systems for ILI that can be enhanced locally when needed.

A human-like H1N2 influenza virus detected during an outbreak of acute respiratory disease in swine in Brazil.

Science.gov (United States)

Schaefer, Rejane; Rech, Raquel Rubia; Gava, Danielle; Cantão, Mauricio Egídio; da Silva, Marcia Cristina; Silveira, Simone; Zanella, Janice Reis Ciacci

2015-01-01

Passive monitoring for detection of influenza A viruses (IAVs) in pigs has been carried out in Brazil since 2009, detecting mostly the A(H1N1)pdm09 influenza virus. Since then, outbreaks of acute respiratory disease suggestive of influenza A virus infection have been observed frequently in Brazilian pig herds. During a 2010-2011 influenza monitoring, a novel H1N2 influenza virus was detected in nursery pigs showing respiratory signs. The pathologic changes were cranioventral acute necrotizing bronchiolitis to subacute proliferative and purulent bronchointerstitial pneumonia. Lung tissue samples were positive for both influenza A virus and A(H1N1)pdm09 influenza virus based on RT-qPCR of the matrix gene. Two IAVs were isolated in SPF chicken eggs. HI analysis of both swine H1N2 influenza viruses showed reactivity to the H1δ cluster. DNA sequencing was performed for all eight viral gene segments of two virus isolates. According to the phylogenetic analysis, the HA and NA genes clustered with influenza viruses of the human lineage (H1-δ cluster, N2), whereas the six internal gene segments clustered with the A(H1N1)pdm09 group. This is the first report of a reassortant human-like H1N2 influenza virus derived from pandemic H1N1 virus causing an outbreak of respiratory disease in pigs in Brazil. The emergence of a reassortant IAV demands the close monitoring of pigs through the full-genome sequencing of virus isolates in order to enhance genetic information about IAVs circulating in pigs.

H5N2 Highly Pathogenic Avian Influenza Viruses from the US 2014-2015 outbreak have an unusually long pre-clinical period in turkeys

OpenAIRE

Spackman, Erica; Pantin-Jackwood, Mary J.; Kapczynski, Darrell R.; Swayne, David E.; Suarez, David L.

2016-01-01

Background From December 2014 through June 2015, the US experienced the most costly highly pathogenic avian influenza (HPAI) outbreak to date. Most cases in commercial poultry were caused by an H5N2 strain which was a reassortant with 5 Eurasian lineage genes, including a clade 2.3.4.4 goose/Guangdong/1996 lineage hemagglutinin, and 3 genes from North American wild waterfowl low pathogenicity avian influenza viruses. The outbreak primarily affected turkeys and table-egg layer type chickens. T...

Wind-Mediated Spread of Low-Pathogenic Avian Influenza Virus into the Environment during Outbreaks at Commercial Poultry Farms.

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Marcel Jonges

Full Text Available Avian influenza virus-infected poultry can release a large amount of virus-contaminated droppings that serve as sources of infection for susceptible birds. Much research so far has focused on virus spread within flocks. However, as fecal material or manure is a major constituent of airborne poultry dust, virus-contaminated particulate matter from infected flocks may be dispersed into the environment. We collected samples of suspended particulate matter, or the inhalable dust fraction, inside, upwind and downwind of buildings holding poultry infected with low-pathogenic avian influenza virus, and tested them for the presence of endotoxins and influenza virus to characterize the potential impact of airborne influenza virus transmission during outbreaks at commercial poultry farms. Influenza viruses were detected by RT-PCR in filter-rinse fluids collected up to 60 meters downwind from the barns, but virus isolation did not yield any isolates. Viral loads in the air samples were low and beyond the limit of RT-PCR quantification except for one in-barn measurement showing a virus concentration of 8.48 x 10(4 genome copies/m(3. Air samples taken outside poultry barns had endotoxin concentrations of ~50 EU/m(3 that declined with increasing distance from the barn. Atmospheric dispersion modeling of particulate matter, using location-specific meteorological data for the sampling days, demonstrated a positive correlation between endotoxin measurements and modeled particulate matter concentrations, with an R(2 varying from 0.59 to 0.88. Our data suggest that areas at high risk for human or animal exposure to airborne influenza viruses can be modeled during an outbreak to allow directed interventions following targeted surveillance.

Outbreak of highly pathogenic avian influenza in Minnesota in 2015.

Science.gov (United States)

Fitzpatrick, Ann; Mor, Sunil K; Thurn, Mary; Wiedenman, Elizabeth; Otterson, Tracy; Porter, Robert E; Patnayak, Devi P; Lauer, Dale C; Voss, Shauna; Rossow, Stephanie; Collins, James E; Goyal, Sagar M

2017-03-01

The incursion of highly pathogenic avian influenza (HPAI) into the United States during 2014 resulted in an unprecedented foreign animal disease (FAD) event; 232 outbreaks were reported from 21 states. The disease affected 49.6 million birds and resulted in economic losses of $950 million. Minnesota is the largest turkey-producing state, accounting for 18% of U.S. turkey production. Areas with concentrated numbers of turkeys in Minnesota were the epicenter of the outbreak. The first case was presumptively diagnosed in the last week of February 2015 at the Minnesota Veterinary Diagnostic Laboratory (MVDL) and confirmed as HPAI H5N2 at the National Veterinary Services Laboratories on March 4, 2015. A total of 110 farms were affected in Minnesota, and the MVDL tested >17,000 samples from March to July 2015. Normal service was maintained to other clients of the laboratory during this major FAD event, but challenges were encountered with communications, staff burnout and fatigue, training requirements of volunteer technical staff, test kit validation, and management of specific pathogen-free egg requirements.

Teachers' Risk Perception and Needs in Addressing Infectious Disease Outbreak

Science.gov (United States)

Wong, Emmy M. Y.; Cheng, May M. H.; Lo, S.K.

2010-01-01

The outbreak of the Influenza A (H1N1) virus has led to numerous precautionary school closures in several countries. No research is available on the school teachers' perceptions as a health protective resource in controlling communicable disease outbreaks. The purposes of this study were to examine the risk perception, the perceived understanding…

Preventing drug resistance in severe influenza

Science.gov (United States)

Dobrovolny, Hana; Deecke, Lucas

2015-03-01

Severe, long-lasting influenza infections are often caused by new strains of influenza. The long duration of these infections leads to an increased opportunity for the emergence of drug resistant mutants. This is particularly problematic for new strains of influenza since there is often no vaccine, so drug treatment is the first line of defense. One strategy for trying to minimize drug resistance is to apply periodic treatment. During treatment the wild-type virus decreases, but resistant virus might increase; when there is no treatment, wild-type virus will hopefully out-compete the resistant virus, driving down the number of resistant virus. We combine a mathematical model of severe influenza with a model of drug resistance to study emergence of drug resistance during a long-lasting infection. We apply periodic treatment with two types of antivirals: neuraminidase inhibitors, which block release of virions; and adamantanes, which block replication of virions. We compare the efficacy of the two drugs in reducing emergence of drug resistant mutants and examine the effect of treatment frequency on the emergence of drug resistant mutants.

Outbreak of H3N2 influenza at a US military base in Djibouti during the H1N1 pandemic of 2009.

Directory of Open Access Journals (Sweden)

Michael T Cosby

Full Text Available BACKGROUND: Influenza pandemics have significant operational impact on deployed military personnel working in areas throughout the world. The US Department of Defense global influenza-like illness (ILI surveillance network serves an important role in establishing baseline trends and can be leveraged to respond to outbreaks of respiratory illness. OBJECTIVE: We identified and characterized an operationally unique outbreak of H3N2 influenza at Camp Lemonnier, Djibouti occurring simultaneously with the H1N1 pandemic of 2009 [A(H1N1pdm09]. METHODS: Enhanced surveillance for ILI was conducted at Camp Lemonnier in response to local reports of a possible outbreak during the A(H1N1pdm09 pandemic. Samples were collected from consenting patients presenting with ILI (utilizing a modified case definition and who completed a case report form. Samples were cultured and analyzed using standard real-time reverse transcriptase PCR (rt-RT-PCR methodology and sequenced genetic material was phylogenetically compared to other published strains. RESULTS: rt-RT-PCR and DNA sequencing revealed that 25 (78% of the 32 clinical samples collected were seasonal H3N2 and only 2 (6% were A(H1N1pdm09 influenza. The highest incidence of H3N2 occurred during the month of May and 80% of these were active duty military personnel. Phylogenetic analysis revealed that sequenced H3N2 strains were genetically similar to 2009 strains from the United States of America, Australia, and South east Asia. CONCLUSIONS: This outbreak highlights challenges in the investigation of influenza among deployed military populations and corroborates the public health importance of maintaining surveillance systems for ILI that can be enhanced locally when needed.

An Outbreak of 2009 Pandemic Influenza A (H1N1) Virus Infection in an Elementary School in Pennsylvania

Science.gov (United States)

Bhattarai, Achuyt; Fagan, Ryan P.; Ostroff, Stephen; Sodha, Samir V.; Moll, Mària E.; Lee, Bruce Y.; Chang, Chung-Chou H.; Ennis, Brent; Britz, Phyllis; Fiore, Anthony; Nguyen, Michael; Palekar, Rakhee; Archer, W. Roodly; Gift, Thomas L.; Leap, Rebecca; Nygren, Benjamin L.; Cauchemez, Simon; Angulo, Frederick J.; Swerdlow, David

2011-01-01

In May 2009, one of the earliest outbreaks of 2009 pandemic influenza A virus (pH1N1) infection resulted in the closure of a semi-rural Pennsylvania elementary school. Two sequential telephone surveys were administered to 1345 students (85% of the students enrolled in the school) and household members in 313 households to collect data on influenza-like illness (ILI). A total of 167 persons (12.4%) among those in the surveyed households, including 93 (24.0%) of the School A students, reported ILI. Students were 3.1 times more likely than were other household members to develop ILI (95% confidence interval [CI], 2.3–4.1). Fourth-grade students were more likely to be affected than were students in other grades (relative risk, 2.2; 95% CI, 1.2–3.9). pH1N1 was confirmed in 26 (72.2%) of the individuals tested by real-time reverse-transcriptase polymerase chain reaction. The outbreak did not resume upon the reopening of the school after the 7-day closure. This investigation found that pH1N1 outbreaks at schools can have substantial attack rates; however, grades and classrooms are affected variably. Additioanl study is warranted to determine the effectiveness of school closure during outbreaks. PMID:21342888

Avian influenza

Science.gov (United States)

Bird flu; H5N1; H5N2; H5N8; H7N9; Avian influenza A (HPAI) H5 ... The first avian influenza in humans was reported in Hong Kong in 1997. It was called avian influenza (H5N1). The outbreak was linked ...

Controlling equine influenza: policy networks and decision-making during the 2007 Australian equine influenza outbreak.

Science.gov (United States)

Schemann, K; Gillespie, J A; Toribio, J-A L M L; Ward, M P; Dhand, N K

2014-10-01

Rapid, evidence-based decision-making is critical during a disease outbreak response; however, compliance by stakeholders is necessary to ensure that such decisions are effective - especially if the response depends on voluntary action. This mixed method study evaluated technical policy decision-making processes during the 2007 outbreak of equine influenza in Australia by identifying and analysing the stakeholder network involved and the factors driving policy decision-making. The study started with a review of the outbreak literature and published policy documents. This identified six policy issues regarding policy modifications or differing interpretations by different state agencies. Data on factors influencing the decision-making process for these six issues and on stakeholder interaction were collected using a pre-tested, semi-structured questionnaire. Face-to-face interviews were conducted with 24 individuals representing 12 industry and government organizations. Quantitative data were analysed using social network analysis. Qualitative data were coded and patterns matched to test a pre-determined general theory using a method called theory-oriented process-tracing. Results revealed that technical policy decisions were framed by social, political, financial, strategic and operational considerations. Industry stakeholders had influence through formal pre-existing channels, yet specific gaps in stakeholder interaction were overcome by reactive alliances formed during the outbreak response but outside the established system. Overall, the crisis management system and response were seen as positive, and 75-100% of individuals interviewed were supportive of, had interest in and considered the outcome as good for the majority of policy decisions, yet only 46-75% of those interviewed considered that they had influence on these decisions. Training to increase awareness and knowledge of emergency animal diseases (EADs) and response systems will improve stakeholder

The Relationship of Avian Influenza and Waterbirds in Creating Genetic Diversity and the Role of Waterbirds as Reservoir for Avian Influenza

Directory of Open Access Journals (Sweden)

Dyah Ayu Hewajuli

2012-03-01

Full Text Available Outbreaks of Avian Influenza (AI has enormous implications for poultry and human health.These outbreaks are caused by influenza A virus that belongS to the family of Orthomyxoviridae. These viruses are RNA viruses, negative polarity, and the envelope has segmented genom. Generally, Avian Influenza is a disease which originally occurred in birds with complex ecology including reassortment and transmission among different species of birds and mammals. The gene of AI virus can be transmitted among human and avian species as shown by the virus reasortantment that caused pandemic human influenza in 1957 and 1968. Pandemi in 1957 and 1968 were different from previously human viruses because the substitution of several genes are derived from avian viruses. Wild waterfowls especially Anseriformes (duck, muscovy duck and geese and Charadriiformes (gulls, seabirds, wild birds are the natural reservoirs for influenza type A viruses and play important role on the ecology and propagation of the virus. From this reservoir, influenza type A virus usually can be transmitted to other birds, mammals (including human and caused outbreak of lethal diseases. Waterfowl that is infected with influenza A virus usually does not show any clinical symptoms. However, several reports stated that HPAI viruses can cause severe disease with neurogical disorders led to death in waterfowl. Migration of birds including waterfowls have active role in transmitting and spreading the disease. Movement of wild birds and inappropriate poultry trade transportation play a greater role as vector in spreading HPAI to humans. Ecological change of environment has also a great effect in spreading AI viruses. The spreading pattern of AI viruses is usually influenced by seasons, where the prevalence of AI was reported to be in the fall, winter and rainy seasons. Finally, the effective control strategies against the spreading of AI viruses is required. Programs of monitoring, surveilence and

Genetic Data Provide Evidence for Wind-Mediated Transmission of Highly Pathogenic Avian Influenza

NARCIS (Netherlands)

Ypma, R.J.F.; Jonges, M.; Bataille, A.M.A.; Stegeman, J.A.; Koch, G.; van Boven, R.M.; Koopmans, M.; van Ballegooijen, W.M.; Wallinga, J.

2013-01-01

Outbreaks of highly pathogenic avian influenza in poultry can cause severe economic damage and represent a public health threat. Development of efficient containment measures requires an understanding of how these influenza viruses are transmitted between farms. However, the actual mechanisms of

Grasshopper species composition shifts following a severe rangeland grasshopper outbreak

Science.gov (United States)

Little is known about how grasshopper species abundances shift during and following severe outbreaks, as sampling efforts usually end when outbreaks subside. Grasshopper densities, species composition and vegetation have infrequently been sampled during and after a severe outbreak in the western U.S...

Different environmental drivers of highly pathogenic avian influenza H5N1 outbreaks in poultry and wild birds

NARCIS (Netherlands)

Si, Y.; Boer, de W.F.; Gong, P.

2013-01-01

A large number of highly pathogenic avian influenza (HPAI) H5N1 outbreaks in poultry and wild birds have been reported in Europe since 2005. Distinct spatial patterns in poultry and wild birds suggest that different environmental drivers and potentially different spread mechanisms are operating.

To report or not to report: a psychosocial investigation aimed at improving early detection of avian influenza outbreaks

NARCIS (Netherlands)

Elbers, A.R.W.; Gorgievski, M.J.; Zarafshani, K.; Koch, G.

2010-01-01

The aim of this study was to identify limitations - and solutions for those limitations – with respect to reporting clinically suspect situations on poultry farms, possibly caused by Avian Influenza (AI) with the ultimate aim to facilitate early detection of AI-outbreaks. Focus group sessions were

On the relative role of different age groups in influenza epidemics.

Science.gov (United States)

Worby, Colin J; Chaves, Sandra S; Wallinga, Jacco; Lipsitch, Marc; Finelli, Lyn; Goldstein, Edward

2015-12-01

The identification of key "driver" groups in influenza epidemics is of much interest for the implementation of effective public health response strategies, including vaccination programs. However, the relative importance of different age groups in propagating epidemics is uncertain. During a communicable disease outbreak, some groups may be disproportionately represented during the outbreak's ascent due to increased susceptibility and/or contact rates. Such groups or subpopulations can be identified by considering the proportion of cases within the subpopulation occurring before (Bp) and after the epidemic peak (Ap) to calculate the subpopulation's relative risk, RR=Bp/Ap. We estimated RR for several subpopulations (age groups) using data on laboratory-confirmed US influenza hospitalizations during epidemics between 2009-2014. Additionally, we simulated various influenza outbreaks in an age-stratified population, relating the RR to the impact of vaccination in each subpopulation on the epidemic's initial effective reproductive number R_e(0). We found that children aged 5-17 had the highest estimates of RR during the five largest influenza A outbreaks, though the relative magnitude of RR in this age group compared to other age groups varied, being highest for the 2009 A/H1N1 pandemic. For the 2010-2011 and 2012-2013 influenza B epidemics, adults aged 18-49, and 0-4 year-olds had the highest estimates of RR respectively. For 83% of simulated epidemics, the group with the highest RR was also the group for which initial distribution of a given quantity of vaccine would result in the largest reduction of R_e(0). In the largest 40% of simulated outbreaks, the group with the highest RR and the largest vaccination impact was children 5-17. While the relative importance of different age groups in propagating influenza outbreaks varies, children aged 5-17 play the leading role during the largest influenza A epidemics. Extra vaccination efforts for this group may contribute

Assessing the role of contact tracing in a suspected H7N2 influenza A outbreak in humans in Wales

Directory of Open Access Journals (Sweden)

Salmon Roland

2010-05-01

Full Text Available Abstract Background The detailed analysis of an outbreak database has been undertaken to examine the role of contact tracing in controlling an outbreak of possible avian influenza in humans. The outbreak, initiating from the purchase of infected domestic poultry, occurred in North Wales during May and June 2007. During this outbreak, extensive contact tracing was carried out. Following contact tracing, cases and contacts believed to be at risk of infection were given treatment/prophylaxis. Methods We analyse the database of cases and their contacts identified for the purposes of contact tracing in relation to both the contact tracing burden and effectiveness. We investigate the distribution of numbers of contacts identified, and use network structure to explore the speed with which treatment/prophylaxis was made available and to estimate the risk of transmission in different settings. Results Fourteen cases of suspected H7N2 influenza A in humans were associated with a confirmed outbreak among poultry in May-June 2007. The contact tracing dataset consisted of 254 individuals (cases and contacts, of both poultry and humans who were linked through a network of social contacts. Of these, 102 individuals were given treatment or prophylaxis. Considerable differences between individuals' contact patterns were observed. Home and workplace encounters were more likely to result in transmission than encounters in other settings. After an initial delay, while the outbreak proceeded undetected, contact tracing rapidly caught up with the cases and was effective in reducing the time between onset of symptoms and treatment/prophylaxis. Conclusions Contact tracing was used to link together the individuals involved in this outbreak in a social network, allowing the identification of the most likely paths of transmission and the risks of different types of interactions to be assessed. The outbreak highlights the substantial time and cost involved in contact

Assessing the role of contact tracing in a suspected H7N2 influenza A outbreak in humans in Wales.

Science.gov (United States)

Eames, Ken T D; Webb, Cerian; Thomas, Kathrin; Smith, Josie; Salmon, Roland; Temple, J Mark F

2010-05-28

The detailed analysis of an outbreak database has been undertaken to examine the role of contact tracing in controlling an outbreak of possible avian influenza in humans. The outbreak, initiating from the purchase of infected domestic poultry, occurred in North Wales during May and June 2007. During this outbreak, extensive contact tracing was carried out. Following contact tracing, cases and contacts believed to be at risk of infection were given treatment/prophylaxis. We analyse the database of cases and their contacts identified for the purposes of contact tracing in relation to both the contact tracing burden and effectiveness. We investigate the distribution of numbers of contacts identified, and use network structure to explore the speed with which treatment/prophylaxis was made available and to estimate the risk of transmission in different settings. Fourteen cases of suspected H7N2 influenza A in humans were associated with a confirmed outbreak among poultry in May-June 2007. The contact tracing dataset consisted of 254 individuals (cases and contacts, of both poultry and humans) who were linked through a network of social contacts. Of these, 102 individuals were given treatment or prophylaxis. Considerable differences between individuals' contact patterns were observed. Home and workplace encounters were more likely to result in transmission than encounters in other settings. After an initial delay, while the outbreak proceeded undetected, contact tracing rapidly caught up with the cases and was effective in reducing the time between onset of symptoms and treatment/prophylaxis. Contact tracing was used to link together the individuals involved in this outbreak in a social network, allowing the identification of the most likely paths of transmission and the risks of different types of interactions to be assessed. The outbreak highlights the substantial time and cost involved in contact tracing, even for an outbreak affecting few individuals. However, when

Avian Influenza.

Science.gov (United States)

Zeitlin, Gary Adam; Maslow, Melanie Jane

2005-05-01

The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate more than 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantining, and disinfection. To prepare for and prevent an increase in human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short-interfering RNAs and new vaccine strategies that use plasmid-based genetic systems, offer promise should a pandemic occur.

Severe pediatric influenza in California, 2003-2005: implications for immunization recommendations.

Science.gov (United States)

Louie, Janice K; Schechter, Robert; Honarmand, Somayeh; Guevara, Hugo F; Shoemaker, Trevor R; Madrigal, Nora Y; Woodfill, Celia J I; Backer, Howard D; Glaser, Carol A

2006-04-01

The 2003-2004 influenza season was marked by both the emergence of a new drift "Fujian" strain of influenza A virus and prominent reports of increased influenza-related deaths in children in the absence of baseline data for comparison. In December 2003, the California Department of Health Services initiated surveillance of children who were hospitalized in California with severe influenza in an attempt to measure its impact and to identify additional preventive measures. From December 2003 to May 2005, surveillance of children who were hospitalized in PICUs or dying in the hospital with laboratory evidence of influenza was performed by hospital infection control practitioners and local public health departments using a standardized case definition and reporting form. In the 2003-2004 and 2004-2005 influenza seasons, 125 and 35 cases, respectively, of severe influenza in children were identified in California. The mean and median age of cases were 3.1 years and 1.5 years, with breakdown as follows: AAP) recommendations for immunization, but only 8 had been vaccinated. More than 3 times as many children were reported to be hospitalized in intensive care with influenza in California during the 2003-2004 season compared with the 2004-2005 season. Because children who are younger than 6 months remain at highest risk for severe influenza yet cannot currently be immunized, development and validation of preventive measures for them (eg, maternal immunization, breastfeeding, immunization of young infants and their close contacts) are urgently needed. ACIP's recent recommendation for influenza vaccination of children with conditions that can compromise respiratory function (eg, cognitive dysfunction, spinal cord injuries, seizure disorders, other neuromuscular disorders) is further supported by the frequency of underlying neurologic disease in these cases of severe influenza. A significant proportion of children with severe influenza in California, including children who are

Transmission of H7N7 avian influenza A virus to human beings during a large outbreak in commercial poultry farms in the Netherlands.

NARCIS (Netherlands)

Koopmans, M.; Wilbrink, B.; Conyn, M.; Natrop, G.; Nat, H. van der; Vennema, H.; Meijer, A.; Steenbergen, J. van; Fouchier, R.; Osterhaus, A.; Bosman, A.

2004-01-01

BACKGROUND: An outbreak of highly pathogenic avian influenza A virus subtype H7N7 started at the end of February, 2003, in commercial poultry farms in the Netherlands. Although the risk of transmission of these viruses to humans was initially thought to be low, an outbreak investigation was launched

Movements of Wild Ruddy Shelducks in the Central Asian Flyway and Their Spatial Relationship to Outbreaks of Highly Pathogenic Avian Influenza H5N1

Directory of Open Access Journals (Sweden)

Scott H. Newman

2013-09-01

Full Text Available Highly pathogenic avian influenza H5N1 remains a serious concern for both poultry and human health. Wild waterfowl are considered to be the reservoir for low pathogenic avian influenza viruses; however, relatively little is known about their movement ecology in regions where HPAI H5N1 outbreaks regularly occur. We studied movements of the ruddy shelduck (Tadorna ferruginea, a wild migratory waterfowl species that was infected in the 2005 Qinghai Lake outbreak. We defined their migration with Brownian Bridge utilization distribution models and their breeding and wintering grounds with fixed kernel home ranges. We correlated their movements with HPAI H5N1 outbreaks, poultry density, land cover, and latitude in the Central Asian Flyway. Our Akaike Information Criterion analysis indicated that outbreaks were correlated with land cover, latitude, and poultry density. Although shelduck movements were included in the top two models, they were not a top parameter selected in AICc stepwise regression results. However, timing of outbreaks suggested that outbreaks in the flyway began during the winter in poultry with spillover to wild birds during the spring migration. Thus, studies of the movement ecology of wild birds in areas with persistent HPAI H5N1 outbreaks may contribute to understanding their role in transmission of this disease.

Movements of wild ruddy shelducks in the Central Asian Flyway and their spatial relationship to outbreaks of highly pathogenic avian influenza H5N1

Science.gov (United States)

Takekawa, John Y.; Prosser, Diann J.; Collins, Bridget M.; Douglas, David C.; Perry, William M.; Baoping, Yan; Luo, Ze; Hou, Yuansheng; Lei, Fumin; Li, Tianxian; Li, Yongdong; Newman, Scott H.

2013-01-01

Highly pathogenic avian influenza H5N1 remains a serious concern for both poultry and human health. Wild waterfowl are considered to be the reservoir for low pathogenic avian influenza viruses; however, relatively little is known about their movement ecology in regions where HPAI H5N1 outbreaks regularly occur. We studied movements of the ruddy shelduck (Tadorna ferruginea), a wild migratory waterfowl species that was infected in the 2005 Qinghai Lake outbreak. We defined their migration with Brownian Bridge utilization distribution models and their breeding and wintering grounds with fixed kernel home ranges. We correlated their movements with HPAI H5N1 outbreaks, poultry density, land cover, and latitude in the Central Asian Flyway. Our Akaike Information Criterion analysis indicated that outbreaks were correlated with land cover, latitude, and poultry density. Although shelduck movements were included in the top two models, they were not a top parameter selected in AICc stepwise regression results. However, timing of outbreaks suggested that outbreaks in the flyway began during the winter in poultry with spillover to wild birds during the spring migration. Thus, studies of the movement ecology of wild birds in areas with persistent HPAI H5N1 outbreaks may contribute to understanding their role in transmission of this disease.

Surveillance for highly pathogenic avian influenza virus in wild birds during outbreaks in domestic poultry, Minnesota, 2015

Science.gov (United States)

Jennelle, Christopher S.; Carstensen, Michelle; Hildebrand, Erik C.; Cornicelli, Louis; Wolf, Paul C.; Grear, Daniel A.; Ip, Hon S.; VanDalen, Kaci K.; Minicucci, Larissa A.

2016-01-01

In 2015, a major outbreak of highly pathogenic avian influenza virus (HPAIV) infection devastated poultry facilities in Minnesota, USA. To clarify the role of wild birds, we tested 3,139 waterfowl fecal samples and 104 sick and dead birds during March 9–June 4, 2015. HPAIV was isolated from a Cooper’s hawk but not from waterfowl.

Avian influenza: a review.

Science.gov (United States)

Thomas, Jennifer K; Noppenberger, Jennifer

2007-01-15

A review of the avian influenza A/H5N1 virus, including human cases, viral transmission, clinical features, vaccines and antivirals, surveillance plans, infection control, and emergency response plans, is presented. The World Health Organization (WHO) considers the avian influenza A/H5N1 virus a public health risk with pandemic potential. The next human influenza pandemic, if caused by the avian influenza A/H5N1 virus, is estimated to have a potential mortality rate of more than a hundred million. Outbreaks in poultry have been associated with human transmission. WHO has documented 258 confirmed human infections with a mortality rate greater than 50%. Bird-to-human transmission of the avian influenza virus is likely by the oral-fecal route. The most effective defense against an influenza pandemic would be a directed vaccine to elicit a specific immune response toward the strain or strains of the influenza virus. However, until there is an influenza pandemic, there is no evidence that vaccines or antivirals used in the treatment or prevention of such an outbreak would decrease morbidity or mortality. Surveillance of the bird and human populations for the highly pathogenic H5N1 is being conducted. Infection-control measures and an emergency response plan are discussed. Avian influenza virus A/H5N1 is a public health threat that has the potential to cause serious illness and death in humans. Understanding its pathology, transmission, clinical features, and pharmacologic treatments and preparing for the prevention and management of its outbreak will help avoid its potentially devastating consequences.

Highly pathogenic avian influenza.

Science.gov (United States)

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.

Statins in influenza: time for a controlled clinical study.

Science.gov (United States)

Carrillo-Esper, Raúl

2009-01-01

Mexico recently experienced the impact of an influenza epidemic. This outbreak, the H1N1 strain, affected a large number of citizens and caused panic, economic instability and increased health care costs to the federal government and public and private institutions. Influenza outbreaks are periodic. They may or may not be seasonal, and severity of the disease is linked to host immunity and to the virus strain. In the event of a pandemic as happened in 1918, it is estimated that approximately 175-350 million people may die, and health systems would face a catastrophic situation due to the insufficiency of antivirals and vaccines, as well as affecting hospital infrastructure.

Cytokine Profiles of Severe Influenza Virus-Related Complications in Children

OpenAIRE

Andrew Fiore-Gartland; Angela Panoskaltsis-Mortari; Anna A. Agan; Anushay J. Mistry; Paul G. Thomas; Michael A. Matthay; Michael A. Matthay; PALISI PICFlu Investigators; Tomer Hertz; Tomer Hertz; Tomer Hertz; Adrienne G. Randolph; Adrienne G. Randolph; Adrienne G. Randolph; Ronald C. Sanders

2017-01-01

RationaleEffective immunomodulatory therapies for children with life-threatening “cytokine storm” triggered by acute influenza infection are lacking. Understanding the immune profiles of children progressing to severe lung injury and/or septic shock could provide insight into pathogenesis.ObjectivesTo compare the endotracheal and serum cytokine profiles of children with influenza-related critical illness and to identify their associations with severe influenza-associated complications.Methods...

Household responses to school closure resulting from outbreak of influenza B, North Carolina.

Science.gov (United States)

Johnson, April J; Moore, Zack S; Edelson, Paul J; Kinnane, Lynda; Davies, Megan; Shay, David K; Balish, Amanda; McCarron, Meg; Blanton, Lenee; Finelli, Lyn; Averhoff, Francisco; Bresee, Joseph; Engel, Jeffrey; Fiore, Anthony

2008-07-01

School closure is a proposed strategy for reducing influenza transmission during a pandemic. Few studies have assessed how families respond to closures, or whether other interactions during closure could reduce this strategy's effect. Questionnaires were administered to 220 households (438 adults and 355 children) with school-age children in a North Carolina county during an influenza B virus outbreak that resulted in school closure. Closure was considered appropriate by 201 (91%) households. No adults missed work to solely provide childcare, and only 22 (10%) households required special childcare arrangements; 2 households incurred additional costs. Eighty-nine percent of children visited at least 1 public location during the closure despite county recommendations to avoid large gatherings. Although behavior and attitudes might differ during a pandemic, these results suggest short-term closure did not cause substantial hardship for parents. Pandemic planning guidance should address the potential for transmission in public areas during school closure.

The health and economic impact of vaccination with 7-valent pneumococcal vaccine (PCV7) during an annual influenza epidemic and influenza pandemic in China.

Science.gov (United States)

Caldwell, Ronald; Roberts, Craig S; An, Zhijie; Chen, Chieh-I; Wang, Bruce

2015-07-24

China has experienced several severe outbreaks of influenza over the past century: 1918, 1957, 1968, and 2009. Influenza itself can be deadly; however, the increase in mortality during an influenza outbreak is also attributable to secondary bacterial infections, specifically pneumococcal disease. Given the history of pandemic outbreaks and the associated morbidity and mortality, we investigated the cost-effectiveness of a PCV7 vaccination program in China from the context of typical and pandemic influenza seasons. A decision-analytic model was employed to evaluate the impact of a 7-valent pneumococcal vaccine (PCV7) infant vaccination program on the incidence, mortality, and cost associated with pneumococcal disease during a typical influenza season (15% flu incidence) and influenza pandemic (30% flu incidence) in China. The model incorporated Chinese data where available and included both direct and indirect (herd) effects on the unvaccinated population, assuming a point in time following the initial introduction of the vaccine where the impact of the indirect effects has reached a steady state, approximately seven years following the implementation of the vaccine program. Pneumococcal disease incidence, mortality, and costs were evaluated over a one year time horizon. Healthcare costs were calculated using a payer perspective and included vaccination program costs and direct medical expenditures from pneumococcal disease. The model predicted that routine PCV7 vaccination of infants in China would prevent 5,053,453 cases of pneumococcal disease and 76,714 deaths in a single year during a normal influenza season.The estimated incremental-cost-effectiveness ratios were ¥12,281 (US$1,900) per life-year saved and ¥13,737 (US$2,125) per quality-adjusted-life-year gained. During an influenza pandemic, the model estimated that routine vaccination with PCV7 would prevent 8,469,506 cases of pneumococcal disease and 707,526 deaths, and would be cost-saving. Routine

Clinical and socioeconomic impact of moderate-to-severe versus mild influenza in children.

Science.gov (United States)

Heikkinen, T; Silvennoinen, H; Heinonen, S; Vuorinen, T

2016-07-01

Some studies have assessed the efficacy of influenza vaccination in children separately for moderate-to-severe and any influenza, but the definition used for identifying children with moderate-to-severe illness has not been validated. We analyzed clinical and socioeconomic data from two prospective cohort studies of respiratory infections among children aged ≤13 years (four influenza seasons, 3,416 child-seasons of follow-up). We categorized children with laboratory-confirmed influenza into two mutually exclusive groups of moderate-to-severe and mild influenza using the previously proposed criteria. We obtained the data for the analyses from structured medical records filled out by the study physicians and from daily symptom cards filled out by the parents. Of 434 cases of influenza, 217 (50 %) were classified as moderate-to-severe and 217 (50 %) as mild. The mean duration of fever was 4.0 days in children with moderate-to-severe influenza and 3.1 days in those with milder illness (P socioeconomic impact of influenza is highest. Illness severity should be considered when assessing influenza vaccine effectiveness in children.

Case Report: Severe Imported Influenza Infections Developed during Travel in Reunion Island.

Science.gov (United States)

Allyn, Jérôme; Brottet, Elise; Antok, Emmanuel; Dangers, Laurence; Persichini, Romain; Coolen-Allou, Nathalie; Roquebert, Bénédicte; Allou, Nicolas; Vandroux, David

2017-12-01

We report two cases of severe influenza infection imported by tourist patients from their country of origin and developed during travel. While studies have reported cases of influenza infections acquired during travel, here we examine two cases of severe influenza infection contracted in the country of origin that led to diagnosis and therapeutic problems in the destination country. No international recommendation exists concerning influenza vaccination before travel, and few countries recommend it for all travelers. Our study suggests that travel should be canceled when infectious signs are observed before departure. Influenza is a very common infection that is often benign, but sometimes very severe. The most severe cases include shock, acute respiratory distress syndrome (ARDS), myocarditis, rhabdomyolysis, and multiple organ failure. Management can require exceptional therapies, such as extracorporeal membrane oxygenation. A number of studies have focused on influenza infection in travelers. Cases of influenza acquired during travel have been reported in this literature, but no study has examined cases of influenza imported from the country of origin and developed while abroad. The latter situation may lead to 1) diagnostic problems during the nonepidemic season or in places where diagnostic techniques are lacking and 2) therapeutic difficulties resulting from the unavailability of techniques for the management of severe influenza infection in tourist areas. Here, we report two cases of extremely severe influenza infection imported by tourists from their country of origin and developed during travel.

Modeling and Statistical Analysis of the Spatio-Temporal Patterns of Seasonal Influenza in Israel

Science.gov (United States)

Katriel, Guy; Yaari, Rami; Roll, Uri; Stone, Lewi

2012-01-01

Background Seasonal influenza outbreaks are a serious burden for public health worldwide and cause morbidity to millions of people each year. In the temperate zone influenza is predominantly seasonal, with epidemics occurring every winter, but the severity of the outbreaks vary substantially between years. In this study we used a highly detailed database, which gave us both temporal and spatial information of influenza dynamics in Israel in the years 1998–2009. We use a discrete-time stochastic epidemic SIR model to find estimates and credible confidence intervals of key epidemiological parameters. Findings Despite the biological complexity of the disease we found that a simple SIR-type model can be fitted successfully to the seasonal influenza data. This was true at both the national levels and at the scale of single cities.The effective reproductive number Re varies between the different years both nationally and among Israeli cities. However, we did not find differences in Re between different Israeli cities within a year. R e was positively correlated to the strength of the spatial synchronization in Israel. For those years in which the disease was more “infectious”, then outbreaks in different cities tended to occur with smaller time lags. Our spatial analysis demonstrates that both the timing and the strength of the outbreak within a year are highly synchronized between the Israeli cities. We extend the spatial analysis to demonstrate the existence of high synchrony between Israeli and French influenza outbreaks. Conclusions The data analysis combined with mathematical modeling provided a better understanding of the spatio-temporal and synchronization dynamics of influenza in Israel and between Israel and France. Altogether, we show that despite major differences in demography and weather conditions intra-annual influenza epidemics are tightly synchronized in both their timing and magnitude, while they may vary greatly between years. The predominance of

Equine influenza: An overview

Directory of Open Access Journals (Sweden)

S. P. Waghmare

2010-08-01

Full Text Available Equine influenza virus is a leading cause of respiratory disease in the horses. The disease is the OIE listed disease of equines, ponies, mules and donkeys and spreads very fast. The sporadic outbreaks of the disease have occurred all over the country. Many cases have been reported in Delhi, Meerut, Saharanpur, Jaipur, Hisar, Calcutta, Ahmedabad. Nearly all the horses at Matheran (Hill station were infected with influenza. The disease has spread like wildfire at the stables of Royal Western India Turf Club (RWITC at Pune and suspended the Mumbai racing season for prolonged period of time resulting in marked economic losses. After affecting racing in Mumbai, Calcutta and New Delhi, the dreaded equine influenza has spread to Karnataka and Mysore. An outbreak of disease has marred the racing season across the country. The disease was first detected in Jammu & Kashmir before entering the central region Horses at the army polo clubs and Delhi equestrian center were also affected. As per the recent survey conducted by the army across India, it has been found that 5400 horses are infected so far, especially thoroughbred most severely. Nearly, 95 % of horses on a major farm in India are suspected of suffering from equine influenza. The government also banned inter-state movement of horses for three months to contain the disease. [Vet World 2010; 3(4.000: 194-197

Factors influencing psychological distress during a disease epidemic: Data from Australia's first outbreak of equine influenza

Directory of Open Access Journals (Sweden)

Stevens Garry J

2008-10-01

Full Text Available Abstract Background In 2007 Australia experienced its first outbreak of highly infectious equine influenza. Government disease control measures were put in place to control, contain, and eradicate the disease; these measures included movement restrictions and quarantining of properties. This study was conducted to assess the psycho-social impacts of this disease, and this paper reports the prevalence of, and factors influencing, psychological distress during this outbreak. Methods Data were collected using an online survey, with a link directed to the affected population via a number of industry groups. Psychological distress, as determined by the Kessler 10 Psychological Distress Scale, was the main outcome measure. Results In total, 2760 people participated in this study. Extremely high levels of non-specific psychological distress were reported by respondents in this study, with 34% reporting high psychological distress (K10 > 22, compared to levels of around 12% in the Australian general population. Analysis, using backward stepwise binary logistic regression analysis, revealed that those living in high risk infection (red zones (OR = 2.00; 95% CI: 1.57–2.55; p Conclusion Although, methodologically, this study had good internal validity, it has limited generalisability because it was not possible to identify, bound, or sample the target population accurately. However, this study is the first to collect psychological distress data from an affected population during such a disease outbreak and has potential to inform those involved in assessing the potential psychological impacts of human infectious diseases, such as pandemic influenza.

Genetic data provide evidence for wind-mediated transmission of highly pathogenic avian influenza.

Science.gov (United States)

Ypma, Rolf J F; Jonges, Marcel; Bataille, Arnaud; Stegeman, Arjan; Koch, Guus; van Boven, Michiel; Koopmans, Marion; van Ballegooijen, W Marijn; Wallinga, Jacco

2013-03-01

Outbreaks of highly pathogenic avian influenza in poultry can cause severe economic damage and represent a public health threat. Development of efficient containment measures requires an understanding of how these influenza viruses are transmitted between farms. However, the actual mechanisms of interfarm transmission are largely unknown. Dispersal of infectious material by wind has been suggested, but never demonstrated, as a possible cause of transmission between farms. Here we provide statistical evidence that the direction of spread of avian influenza A(H7N7) is correlated with the direction of wind at date of infection. Using detailed genetic and epidemiological data, we found the direction of spread by reconstructing the transmission tree for a large outbreak in the Netherlands in 2003. We conservatively estimate the contribution of a possible wind-mediated mechanism to the total amount of spread during this outbreak to be around 18%.

Clinical and epidemiologic characteristics of an outbreak of novel H1N1 (swine origin) influenza A virus among United States military beneficiaries.

Science.gov (United States)

Crum-Cianflone, Nancy F; Blair, Patrick J; Faix, Dennis; Arnold, John; Echols, Sara; Sherman, Sterling S; Tueller, John E; Warkentien, Tyler; Sanguineti, Gabriela; Bavaro, Mary; Hale, Braden R

2009-12-15

A novel swine-origin influenza A (H1N1) virus was identified in March 2009 and subsequently caused worldwide outbreaks. The San Diego region was an early focal point of the emerging pandemic. We describe the clinical and epidemiologic characteristics of this novel strain in a military population to assist in future outbreak prevention and control efforts. We performed an epidemiologic evaluation of novel H1N1 virus infections diagnosed in San Diego County among 96,258 local US military beneficiaries. The structured military medical system afforded the ability to obtain precise epidemiologic information on the impact on H1N1 virus infection in a population. The novel H1N1 virus was confirmed using real-time reverse transcriptase polymerase chain reaction (rRT-PCR). From 21 April through 8 May 2009, 761 patients presented with influenza-like illness and underwent rRT-PCR testing. Of these patients, 97 had confirmed novel H1N1 virus infection, with an incidence rate of 101 cases per 100,000 persons. The median age of H1N1 patients with H1N1 virus infection was 21 years (interquartile range, 15-25 years). Fever was a universal symptom in patients with H1N1 virus infection; other symptoms included cough (present in 96% of patients), myalgia or arthralgia (57%), and sore throat (51%). Sixty-eight (70%) of our patients had an identifiable epidemiologic link to another confirmed patient. The largest cluster of cases of H1N1 virus infection occurred on a Navy ship and involved 32 (8%) of 402 crew members; the secondary attack rate was 6%-14%. The rapid influenza testing that was used during this outbreak had a sensitivity of 51% and specificity of 98%, compared with rRT-PCR. Only 1 patient was hospitalized, and there were no deaths. A novel H1N1 influenza A virus caused a significant outbreak among military beneficiaries in San Diego County, including a significant cluster of cases onboard a Navy ship. The outbreak described here primarily affected adolescents and young

Cross talk between animal and human influenza viruses.

Science.gov (United States)

Ozawa, Makoto; Kawaoka, Yoshihiro

2013-01-01

Although outbreaks of highly pathogenic avian influenza in wild and domestic birds have been posing the threat of a new influenza pandemic for the past decade, the first pandemic of the twenty-first century came from swine viruses. This fact emphasizes the complexity of influenza viral ecology and the difficulty of predicting influenza viral dynamics. Complete control of influenza viruses seems impossible. However, we must minimize the impact of animal and human influenza outbreaks by learning lessons from past experiences and recognizing the current status. Here, we review the most recent influenza virology data in the veterinary field, including aspects of zoonotic agents and recent studies that assess the pandemic potential of H5N1 highly pathogenic avian influenza viruses.

Decreasing influenza impact in lodges: 1997-2000 Calgary Regional Health Authority.

Science.gov (United States)

McLeod, L; Lau, W W

2001-01-01

Influenza causes high morbidity and hospitalization rates in residents of seniors lodges, I causing increased pressure on emergency departments and hospital beds every winter. This quasi-experimental study assessed the prevention of influenza outbreaks and their consequences in Calgary lodges. A multidisciplinary team worked to improve communication between health professionals, increase resident and staff immunization coverage, obtain weights and creatinines prior to influenza season, and facilitate amantadine prophylaxis during influenza A outbreaks. We had an increase in standing orders for amantadine and up to 56% of residents from one lodge had documented creatinine levels. Amantadine was administered to residents within two days of outbreak notification. Influenza morbidity in lodge outbreaks decreased from a rate of 37% to 9% over the three years and hospitalization rates decreased from 9% to 1%. We recommend that other regions consider a similar approach to decreasing influenza morbidity and hospitalization in lodge residents.

A "high severity" spruce beetle outbreak in Wyoming causes moderate-severity carbon cycle perturbations

Science.gov (United States)

Berryman, E.; Frank, J. M.; Speckman, H. N.; Bradford, J. B.; Ryan, M. G.; Massman, W. J.; Hawbaker, T. J.

2017-12-01

Bark beetle outbreaks in Western North American forests are often considered a high-severity disturbance from a carbon (C) cycling perspective, but field measurements that quantify impacts on C dynamics are very limited. Often, factors out of the researcher's control complicate the separation of beetle impacts from other drivers of C cycling variability and restrict statistical inference. Fortuitously, we had four years of pre-spruce beetle outbreak C cycle measurements in a subalpine forest in southeastern Wyoming (Glacier Lakes Ecosystem Experiments Site, or GLEES) and sustained intermittent monitoring for nearly a decade after the outbreak. Here, we synthesize published and unpublished pre- and post-outbreak measurements of key C cycle stocks and fluxes at GLEES. Multiple lines of evidence, including chamber measurements, eddy covariance measurements, and tracking of soil and forest floor C pools over time, point to the GLEES outbreak as a moderate-severity disturbance for C loss to the atmosphere, despite 70% to 80% of overstory tree death. Reductions in NEE were short-lived and the forest quickly returned to a carbon-neutral state, likely driven by an uptick in understory growth. Effect of mortality on the C cycle was asymmetrical, with a 50% reduction in net carbon uptake (NEE) two years into the outbreak, yet no measureable change in either ecosystem or growing season soil respiration. A small pulse in soil respiration occurred but was only detectable during the winter and amounted to < 10% of NEE. Possible reasons for the lack of measureable respiration response are discussed with emphasis on lessons learned for monitoring and modeling future outbreaks. We suggest a comprehensive assessment and definition of "moderate-severity" disturbances for Western forests and suggest that all tree mortality events may not be high-severity when it comes to C fluxes.

Establishing a laboratory network of influenza diagnosis in Indonesia: an experience from the avian flu (H5N1 outbreak

Directory of Open Access Journals (Sweden)

Setiawaty V

2012-08-01

Full Text Available Vivi Setiawaty, Krisna NA Pangesti, Ondri D SampurnoNational Institute of Health Research and Development, Ministry of Health, the Republic of Indonesia, Jakarta, IndonesiaAbstract: Indonesia has been part of the global influenza surveillance since the establishment of a National Influenza Center (NIC at the National Institute of Health Research and Development (NIHRD by the Indonesian Ministry of Health in 1975. When the outbreak of avian influenza A (H5N1 occurred, the NIC and US Naval Medical Research Unit 2 were the only diagnostic laboratories equipped for etiology confirmation. The large geographical area of the Republic of Indonesia poses a real challenge to provide prompt and accurate diagnosis nationally. This was the main reason to establish a laboratory network for H5N1 diagnosis in Indonesia. Currently, 44 laboratories have been included in the network capable of performing polymerase chain reaction testing for influenza A. Diagnostic equipment and standard procedures of biosafety and biosecurity of handling specimens have been adopted largely from World Health Organization recommendations.Keywords: influenza, laboratory, networking

Predicting Zoonotic Risk of Influenza A Viruses from Host Tropism Protein Signature Using Random Forest.

Science.gov (United States)

Eng, Christine L P; Tong, Joo Chuan; Tan, Tin Wee

2017-05-25

Influenza A viruses remain a significant health problem, especially when a novel subtype emerges from the avian population to cause severe outbreaks in humans. Zoonotic viruses arise from the animal population as a result of mutations and reassortments, giving rise to novel strains with the capability to evade the host species barrier and cause human infections. Despite progress in understanding interspecies transmission of influenza viruses, we are no closer to predicting zoonotic strains that can lead to an outbreak. We have previously discovered distinct host tropism protein signatures of avian, human and zoonotic influenza strains obtained from host tropism predictions on individual protein sequences. Here, we apply machine learning approaches on the signatures to build a computational model capable of predicting zoonotic strains. The zoonotic strain prediction model can classify avian, human or zoonotic strains with high accuracy, as well as providing an estimated zoonotic risk. This would therefore allow us to quickly determine if an influenza virus strain has the potential to be zoonotic using only protein sequences. The swift identification of potential zoonotic strains in the animal population using the zoonotic strain prediction model could provide us with an early indication of an imminent influenza outbreak.

Influenza Pandemic Infrastructure Response in Thailand

Centers for Disease Control (CDC) Podcasts

Influenza viruses change antigenic properties, or drift, every year and they create seasonal outbreaks. Occasionally, influenza viruses change in a major way, called a “shift." If an influenza virus shifts, the entire human population is susceptible to the new influenza virus, creating the potential for a pandemic. On this podcast, CDC's Dr. Scott Dowell discusses responding to an influenza pandemic.

Pathogenicity of highly pathogenic avian influenza virus in mammals

NARCIS (Netherlands)

de Wit, Emmie; Kawaoka, Yoshihiro; de Jong, Menno D.; Fouchier, Ron A. M.

2008-01-01

In recent years, there has been an increase in outbreaks of highly pathogenic avian influenza (HPAI) in poultry. Occasionally, these outbreaks have resulted in transmission of influenza viruses to humans and other mammals, with symptoms ranging from conjunctivitis to pneumonia and death. Here, the

Economic and policy implications of pandemic influenza.

Energy Technology Data Exchange (ETDEWEB)

Smith, Braeton J.; Starks, Shirley J.; Loose, Verne W.; Brown, Theresa Jean; Warren, Drake E.; Vargas, Vanessa N.

2010-03-01

Pandemic influenza has become a serious global health concern; in response, governments around the world have allocated increasing funds to containment of public health threats from this disease. Pandemic influenza is also recognized to have serious economic implications, causing illness and absence that reduces worker productivity and economic output and, through mortality, robs nations of their most valuable assets - human resources. This paper reports two studies that investigate both the short- and long-term economic implications of a pandemic flu outbreak. Policy makers can use the growing number of economic impact estimates to decide how much to spend to combat the pandemic influenza outbreaks. Experts recognize that pandemic influenza has serious global economic implications. The illness causes absenteeism, reduced worker productivity, and therefore reduced economic output. This, combined with the associated mortality rate, robs nations of valuable human resources. Policy makers can use economic impact estimates to decide how much to spend to combat the pandemic influenza outbreaks. In this paper economists examine two studies which investigate both the short- and long-term economic implications of a pandemic influenza outbreak. Resulting policy implications are also discussed. The research uses the Regional Economic Modeling, Inc. (REMI) Policy Insight + Model. This model provides a dynamic, regional, North America Industrial Classification System (NAICS) industry-structured framework for forecasting. It is supported by a population dynamics model that is well-adapted to investigating macro-economic implications of pandemic influenza, including possible demand side effects. The studies reported in this paper exercise all of these capabilities.

Novel Influenza A (H1N1) Outbreak at the U.S. Air Force Academy: Epidemiology and Viral Shedding Duration (American Journal of Preventive Medicine, Volume 20, Number 10, 2009)

Science.gov (United States)

2009-01-01

virus : zoonotic potential and vaccina- tion strategies for the control of avian and swine influenzas . J Infect Dis 2008;197(1S):S19–24. ber x www.ajpm-online.net ...nsubtypeable influenza A virus from patient samples. he viral specimens were transported to the CDC nfluenza laboratory, where both viral samples were...etermined to be a novel influenza A virus of swine rigin (nH1N1), consistent with virus isolated from atients in a Mexico influenza outbreak that began

The effects of school closures on influenza outbreaks and pandemics: systematic review of simulation studies.

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Jackson, Charlotte; Mangtani, Punam; Hawker, Jeremy; Olowokure, Babatunde; Vynnycky, Emilia

2014-01-01

School closure is a potential intervention during an influenza pandemic and has been investigated in many modelling studies. To systematically review the effects of school closure on influenza outbreaks as predicted by simulation studies. We searched Medline and Embase for relevant modelling studies published by the end of October 2012, and handsearched key journals. We summarised the predicted effects of school closure on the peak and cumulative attack rates and the duration of the epidemic. We investigated how these predictions depended on the basic reproduction number, the timing and duration of closure and the assumed effects of school closures on contact patterns. School closures were usually predicted to be most effective if they caused large reductions in contact, if transmissibility was low (e.g. a basic reproduction number 90% reductions or even increases under certain assumptions). This partly reflected differences in model assumptions, such as those regarding population contact patterns. Simulation studies suggest that school closure can be a useful control measure during an influenza pandemic, particularly for reducing peak demand on health services. However, it is difficult to accurately quantify the likely benefits. Further studies of the effects of reactive school closures on contact patterns are needed to improve the accuracy of model predictions.

Preparing for a Pandemic Flu Outbreak

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Dittbenner, Richard

2009-01-01

This article discusses the things college leaders should know and do in case of a pandemic influenza outbreak. The author talks about four principles that will guide college leaders in developing a pandemic influenza plan and presents the 10 elements of an effective college pandemic planning process.

Predicting Zoonotic Risk of Influenza A Viruses from Host Tropism Protein Signature Using Random Forest

Directory of Open Access Journals (Sweden)

Christine L. P. Eng

2017-05-01

Full Text Available Influenza A viruses remain a significant health problem, especially when a novel subtype emerges from the avian population to cause severe outbreaks in humans. Zoonotic viruses arise from the animal population as a result of mutations and reassortments, giving rise to novel strains with the capability to evade the host species barrier and cause human infections. Despite progress in understanding interspecies transmission of influenza viruses, we are no closer to predicting zoonotic strains that can lead to an outbreak. We have previously discovered distinct host tropism protein signatures of avian, human and zoonotic influenza strains obtained from host tropism predictions on individual protein sequences. Here, we apply machine learning approaches on the signatures to build a computational model capable of predicting zoonotic strains. The zoonotic strain prediction model can classify avian, human or zoonotic strains with high accuracy, as well as providing an estimated zoonotic risk. This would therefore allow us to quickly determine if an influenza virus strain has the potential to be zoonotic using only protein sequences. The swift identification of potential zoonotic strains in the animal population using the zoonotic strain prediction model could provide us with an early indication of an imminent influenza outbreak.

[No best treatment for severe outbreaks: Maintenance, the key in colitis].

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Sicilia, Beatriz

2011-12-01

Several drugs are currently available to maintain remission in patients who have responded after one or other type of induction therapy, depending on the initial severity of the outbreak. Salicylates are the drugs of choice to maintain remission after a mild-to-moderate outbreak controlled by salicylates or oral corticosteroids. To maintain remission after a severe outbreak or in patients with corticosteroid dependence or resistance, thiopurines are the drugs of choice. In patients who have failed to respond to thiopurines and in those with thiopurine intolerance, biological agents, mainly infliximab, can be used to maintain remission in patients after induction therapy with infliximab for a severe outbreak. However, these scenarios may not reflect reality of gastroenterologists' daily clinical practice. Treatment will therefore be based on the patient's individual characteristics (age, clinical course, previous treatment, adverse effects and personal preferences) as well as the physician's medical art. Copyright © 2011 Elsevier España, S.L.U. All rights reserved.

Using extreme value theory approaches to forecast the probability of outbreak of highly pathogenic influenza in Zhejiang, China.

Directory of Open Access Journals (Sweden)

Jiangpeng Chen

Full Text Available Influenza is a contagious disease with high transmissibility to spread around the world with considerable morbidity and mortality and presents an enormous burden on worldwide public health. Few mathematical models can be used because influenza incidence data are generally not normally distributed. We developed a mathematical model using Extreme Value Theory (EVT to forecast the probability of outbreak of highly pathogenic influenza.The incidence data of highly pathogenic influenza in Zhejiang province from April 2009 to November 2013 were retrieved from the website of Health and Family Planning Commission of Zhejiang Province. MATLAB "VIEM" toolbox was used to analyze data and modelling. In the present work, we used the Peak Over Threshold (POT model, assuming the frequency as a Poisson process and the intensity to be Pareto distributed, to characterize the temporal variability of the long-term extreme incidence of highly pathogenic influenza in Zhejiang, China.The skewness and kurtosis of the incidence of highly pathogenic influenza in Zhejiang between April 2009 and November 2013 were 4.49 and 21.12, which indicated a "fat tail" distribution. A QQ plot and a mean excess plot were used to further validate the features of the distribution. After determining the threshold, we modeled the extremes and estimated the shape parameter and scale parameter by the maximum likelihood method. The results showed that months in which the incidence of highly pathogenic influenza is about 4462/2286/1311/487 are predicted to occur once every five/three/two/one year, respectively.Despite the simplicity, the present study successfully offers the sound modeling strategy and a methodological avenue to implement forecasting of an epidemic in the midst of its course.

Overview of the industry and social impacts of the 2007 Australian equine influenza outbreak.

Science.gov (United States)

Hoare, R

2011-07-01

The equine influenza (EI) outbreak occurred at the worst time of the year as far as the horse industry was concerned. All horse sports and horse breeds had events planned in the spring, including those relating to qualification for the 2008 Beijing Olympic Games. These were all disrupted and many were cancelled. The social and industry impacts were extensive, and included difficulties related to communication, animal welfare, vaccination, movement restrictions, economics, as well as the psychological stresses experienced by those involved, especially those for whom their primary source of income was horse related. © 2011 The Author. Australian Veterinary Journal © 2011 Australian Veterinary Association.

A definition for influenza pandemics based on historical records.

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Potter, Chris W; Jennings, Roy

2011-10-01

To analyse the records of past influenza outbreaks to determine a definition for pandemics. Analysis of publications of large outbreaks of influenza which have occurred since 1889/90, and to match the results against the current definitions of an influenza pandemic. According to the general understanding of a pandemic, nine outbreaks of influenza since 1889/90 satisfy the definition; however, for two of these, occurring in 1900 and 1933, the data are limited. The special condition for an influenza pandemic requires, in one definition, that the virus strain responsible could not have arisen from the previous circulating strain by mutation; and in the second, that the new strain be a different subtype to the previously circulating strain. Both these restrictions deny pandemic status to two, and possibly three, influenza outbreaks which were pandemics according to the more general understanding of the term. These observations suggest that a re-evaluation of the criteria which define influenza pandemics should be carried out. The contradiction outlined above brings the previous definitions of an influenza pandemic into question; however, this can be resolved by defining an influenza pandemic by the following criteria. Thus, an influenza pandemic arises at a single, specific place and spreads rapidly to involve numerous countries. The haemagglutinin (HA) of the emergent virus does not cross-react serologically with the previously dominant virus strain(s), and there is a significant lack of immunity in the population against the emergent virus. These three criteria are interlinked and can be determined early to alert authorities who could respond appropriately. Other criteria associated with pandemics are necessarily retrospective, although important and valid. The implications of this definition are discussed. Copyright © 2011 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Cytokine Profiles of Severe Influenza Virus-Related Complications in Children

Directory of Open Access Journals (Sweden)

Andrew Fiore-Gartland

2017-11-01

Full Text Available RationaleEffective immunomodulatory therapies for children with life-threatening “cytokine storm” triggered by acute influenza infection are lacking. Understanding the immune profiles of children progressing to severe lung injury and/or septic shock could provide insight into pathogenesis.ObjectivesTo compare the endotracheal and serum cytokine profiles of children with influenza-related critical illness and to identify their associations with severe influenza-associated complications.MethodsChildren with influenza-related critical illness were enrolled across 32 hospitals in development (N = 171 and validation (N = 73 cohorts (December 2008 through May 2016. Concentrations of 42 cytokines were measured in serum and endotracheal samples and clustered into modules of covarying cytokines. Relative concentrations of cytokines and cytokine modules were tested for associations with acute lung injury (ALI, shock requiring vasopressors, and death/ECMO.Measurements and main resultsModules of covarying cytokines were more significantly associated with disease severity than individual cytokines. In the development cohort, increased levels of a serum module containing IL6, IL8, IL10, IP10, GCSF, MCP1, and MIP1α [shock odds ratio (OR = 3.37, family-wise error rate (FWER p < 10−4], and decreased levels of a module containing EGF, FGF2, SCD40L, and PAI-1 (shock OR = 0.43, FWER p = 0.002, were both associated with ALI, shock, and death-ECMO independent of age and bacterial coinfection. Both of these associations were confirmed in the validation cohort. Endotracheal and serum cytokine associations differed markedly and were differentially associated with clinical outcomes.ConclusionWe identified strong positive and negative associations of cytokine modules with the most severe influenza-related complications in children, providing new insights into the pathogenesis of influenza-related critical illness in children. Effective

Ecological Determinants of Highly Pathogenic Avian Influenza (H5N1) Outbreaks in Bangladesh

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Ahmed, Syed S. U.; Ersbøll, Annette K.; Biswas, Paritosh K.; Christensen, Jens P.; Hannan, Abu S. M. A.; Toft, Nils

2012-01-01

Background The agro-ecology and poultry husbandry of the south Asian and south-east Asian countries share common features, however, with noticeable differences. Hence, the ecological determinants associated with risk of highly pathogenic avian influenza (HPAI-H5N1) outbreaks are expected to differ between Bangladesh and e.g., Thailand and Vietnam. The primary aim of the current study was to establish ecological determinants associated with the risk of HPAI-H5N1 outbreaks at subdistrict level in Bangladesh. The secondary aim was to explore the performance of two different statistical modeling approaches for unmeasured spatially correlated variation. Methodology/Principal Findings An ecological study at subdistrict level in Bangladesh was performed with 138 subdistricts with HPAI-H5N1 outbreaks during 2007–2008, and 326 subdistricts with no outbreaks. The association between ecological determinants and HPAI-H5N1 outbreaks was examined using a generalized linear mixed model. Spatial clustering of the ecological data was modeled using 1) an intrinsic conditional autoregressive (ICAR) model at subdistrict level considering their first order neighbors, and 2) a multilevel (ML) model with subdistricts nested within districts. Ecological determinants significantly associated with risk of HPAI-H5N1 outbreaks at subdistrict level were migratory birds' staging areas, river network, household density, literacy rate, poultry density, live bird markets, and highway network. Predictive risk maps were derived based on the resulting models. The resulting models indicate that the ML model absorbed some of the covariate effect of the ICAR model because of the neighbor structure implied in the two different models. Conclusions/Significance The study identified a new set of ecological determinants related to river networks, migratory birds' staging areas and literacy rate in addition to already known risk factors, and clarified that the generalized concept of free grazing duck and

Epidemiology, production losses, and control measures associated with an outbreak of avian influenza subtype H7N2 in Pennsylvania (1996-98).

Science.gov (United States)

Henzler, D J; Kradel, D C; Davison, S; Ziegler, A F; Singletary, D; DeBok, P; Castro, A E; Lu, H; Eckroade, R; Swayne, D; Lagoda, W; Schmucker, B; Nesselrodt, A

2003-01-01

An outbreak of H7N2 low-pathogenicity (LP) avian influenza (AI) occurred in a two-county area in Pennsylvania from December of 1996 through April of 1998. The outbreak resulted in infection of 2,623,116 commercial birds on 25 premises encompassing 47 flocks. Twenty-one (one premise with infection twice) of the twenty-five infected premises housed egg-laying chickens and one premise each had turkeys, layer pullets, quail, and a mixed backyard dealer flock. Despite dose proximity of infected flocks to commercial broiler flocks, no infected broilers were identified. Experimentally, when market age broilers were placed on an influenza-infected premise they seroconverted and developed oviduct lesions. The outbreak was believed to have originated from two separate introductions into commercial layer flocks from premises and by individuals dealing in sales of live fowl in the metropolitan New York and New Jersey live-bird markets. Source flocks for these markets are primarily in the northeast and mid-Atlantic areas, including Pennsylvania. Mixed fowl sold include ducks, geese, guinea hens, quail, chukar partridges, and a variety of chickens grown on perhaps hundreds of small farms. Infections with the H7N2 AI virus were associated with variable morbidity and temporary decreases in egg production ranging from 1.6% to 29.1% in commercial egg-laying chickens. Egg production losses averaged 4.0 weeks duration. Mortality ranged from 1.5 to 18.3 times normal (mean of 4.3 times normal). Duration of mortality ranged from 2 to 13 weeks (average of 3.9 weeks) in flocks not depopulated. Lesions observed were primarily oviducts filled with a mucous and white gelatinous exudates and atypical egg yolk peritonitis. Quarantine of premises and complete depopulation were the early measures employed in control of this outbreak. Epidemiological studies suggested that depopulation furthered the spread of influenza to nearby flocks. Thereafter, later control measures included quarantine

Influenza Risk Management: Lessons Learned from an A(H1N1) pdm09 Outbreak Investigation in an Operational Military Setting

Science.gov (United States)

2013-07-10

Olalla Peralta P, et al.. Pandemic Influenza (H 1 N 1) 2009 Outbreak in a Military Academy: start of community circulation in Spain. Rev Esp Salud ... Publica 84(5):597-607 5. Kapp L, Jansen DJ (2009) The role of the Department of Defense during a flu pandemic. Washington (DC): CRS Report for Congress

Atmospheric Infrared Sounder on NASA's Aqua Satellite: Applications for Volcano Rapid Response, Influenza Outbreak Prediction, and Drought Onset Prediction

Science.gov (United States)

Ray, S. E.; Fetzer, E. J.; Lambrigtsen, B.; Olsen, E. T.; Licata, S. J.; Hall, J. R.; Penteado, P. F.; Realmuto, V. J.; Thrastarson, H. T.; Teixeira, J.; Granger, S. L.; Behrangi, A.; Farahmand, A.

2017-12-01

The Atmospheric Infrared Sounder (AIRS) has been returning daily global observations of Earth's atmospheric constituents and properties since 2002. With its 15-year data record and near real-time capability, AIRS data are being used in the development of applications that fall within many of the NASA Applied Science focus areas. An automated alert system for volcanic plumes has been developed that triggers on threshold breaches of SO2, ash and dust in granules of AIRS data. The system generates a suite of granule-scale maps that depict both plume and clouds, all accessible from the AIRS web site. Alerts are sent to a curated list of volcano community members, and links to views in NASA Worldview and Google Earth are also available. Seasonal influenza epidemics are major public health concern with millions of cases of severe illness and large economic impact. Recent studies have highlighted the role of absolute or specific humidity as a likely player in the seasonal nature of these outbreaks. A quasi-operational influenza outbreak prediction system has been developed based on the SIRS model which uses AIRS and NCEP humidity data, Center for Disease Control reports on flu and flu-like illnesses, and results from Google Flu Trends. Work is underway to account for diffusion (spatial) in addition to the temporal spreading of influenza. The US Drought Monitor (USDM) is generated weekly by the National Drought Mitigation Center (NDMC) and is used by policymakers for drought decision-making. AIRS data have demonstrated utility in monitoring the development and detection of meteorological drought with both AIRS-derived standardized vapor pressure deficit and standardized relative humidity, showing early detection lead times of up to two months. An agreement was secured with the NDMC to begin a trial period using AIRS products in the production of the USDM, and in July of 2017 the operational delivery of weekly CONUS AIRS images of Relative Humidity, Surface Air Temperature

Fire severity unaffected by spruce beetle outbreak in spruce-fir forests in southwestern Colorado.

Science.gov (United States)

Andrus, Robert A; Veblen, Thomas T; Harvey, Brian J; Hart, Sarah J

2016-04-01

Recent large and severe outbreaks of native bark beetles have raised concern among the general public and land managers about potential for amplified fire activity in western North America. To date, the majority of studies examining bark beetle outbreaks and subsequent fire severity in the U.S. Rocky Mountains have focused on outbreaks of mountain pine beetle (MPB; Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests, but few studies, particularly field studies, have addressed the effects of the severity of spruce beetle (Dendroctonus rufipennis Kirby) infestation on subsequent fire severity in subalpine Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests. In Colorado, the annual area infested by spruce beetle outbreaks is rapidly rising, while MPB outbreaks are subsiding; therefore understanding this relationship is of growing importance. We collected extensive field data in subalpine forests in the eastern San Juan Mountains, southwestern Colorado, USA, to investigate whether a gray-stage (fire) spruce beetle infestation affected fire severity. Contrary to the expectation that bark beetle infestation alters subsequent fire severity, correlation and multivariate generalized linear regression analysis revealed no influence of pre-fire spruce beetle severity on nearly all field or remotely sensed measurements of fire severity. Findings were consistent across moderate and extreme burning conditions. In comparison to severity of the pre-fire beetle outbreak, we found that topography, pre-outbreak basal area, and weather conditions exerted a stronger effect on fire severity. Our finding that beetle infestation did not alter fire severity is consistent with previous retrospective studies examining fire activity following other bark beetle outbreaks and reiterates the overriding influence of climate that creates conditions conducive to large, high-severity fires in the subalpine zone of Colorado. Both bark beetle outbreaks and

Evaluation of IFITM3 rs12252 Association With Severe Pediatric Influenza Infection.

Science.gov (United States)

Randolph, Adrienne G; Yip, Wai-Ki; Allen, Emma Kaitlynn; Rosenberger, Carrie M; Agan, Anna A; Ash, Stephanie A; Zhang, Yu; Bhangale, Tushar R; Finkelstein, David; Cvijanovich, Natalie Z; Mourani, Peter M; Hall, Mark W; Su, Helen C; Thomas, Paul G

2017-07-01

Interferon-induced transmembrane protein 3 (IFITM3) restricts endocytic fusion of influenza virus. IFITM3 rs12252_C, a putative alternate splice site, has been associated with influenza severity in adults. IFITM3 has not been evaluated in pediatric influenza. The Pediatric Influenza (PICFLU) study enrolled children with suspected influenza infection across 38 pediatric intensive care units during November 2008 to April 2016. IFITM3 was sequenced in patients and parents were genotyped for specific variants for family-based association testing. rs12252 was genotyped in 54 African-American pediatric outpatients with influenza (FLU09), included in the population-based comparisons with 1000 genomes. Splice site analysis of rs12252_C was performed using PICFLU and FLU09 patient RNA. In PICFLU, 358 children had influenza infection. We identified 22 rs12252_C homozygotes in 185 white non-Hispanic children. rs12252_C was not associated with influenza infection in population or family-based analyses. We did not identify the Δ21 IFITM3 isoform in RNAseq data. The rs12252 genotype was not associated with IFITM3 expression levels, nor with critical illness severity. No novel rare IFITM3 functional variants were identified. rs12252 was not associated with susceptibility to influenza-related critical illness in children or with critical illness severity. Our data also do not support it being a splice site. © 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.

Importance of employee vaccination against influenza in preventing cases in long-term care facilities.

Science.gov (United States)

Wendelboe, Aaron M; Avery, Catherine; Andrade, Bernardo; Baumbach, Joan; Landen, Michael G

2011-10-01

Employees of long-term care facilities (LTCFs) who have contact with residents should be vaccinated against influenza annually to reduce influenza incidence among residents. This investigation estimated the magnitude of the benefit of this recommendation. The New Mexico Department of Health implemented active surveillance in all of its 75 LTCFs during influenza seasons 2006-2007 and 2007-2008. Information about the number of laboratory-confirmed cases of influenza and the proportion vaccinated of both residents and direct-care employees in each facility was collected monthly. LTCFs reporting at least 1 case of influenza (defined alternately by laboratory confirmation or symptoms of influenza-like illness [ILI]) among residents were compared with LTCFs reporting no cases of influenza. Regression modeling was used to obtain adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for the association between employee vaccination coverage and the occurrence of influenza outbreaks. Covariates included vaccination coverage among residents, the staff-to-resident ratio, and the proportion of filled beds. Seventeen influenza outbreaks were reported during this 2-year period of surveillance. Eleven of these were laboratory confirmed (n = 21 residents) and 6 were defined by ILI (n = 40 residents). Mean influenza vaccination coverage among direct-care employees was 51% in facilities reporting outbreaks and 60% in facilities not reporting outbreaks (P = .12). Increased vaccination coverage among direct-care employees was associated with fewer reported outbreaks of laboratory-confirmed influenza (aOR, 0.97 [95% CI, 0.95-0.99]) and ILI (aOR, 0.98 [95% CI, 0.96-1.00]). High vaccination coverage among direct-care employees helps to prevent influenza in LTCFs.

What's new with the flu? Reflections regarding the management and prevention of influenza from the 2nd New Zealand Influenza Symposium, November 2015.

Science.gov (United States)

Charania, Nadia A; Mansoor, Osman D; Murfitt, Diana; Turner, Nikki M

2016-09-09

Influenza is a common respiratory viral infection. Seasonal outbreaks of influenza cause substantial morbidity and mortality that burdens healthcare services every year. The influenza virus constantly evolves by antigenic drift and occasionally by antigenic shift, making this disease particularly challenging to manage and prevent. As influenza viruses cause seasonal outbreaks and also have the ability to cause pandemics leading to widespread social and economic losses, focused discussions on improving management and prevention efforts is warranted. The Immunisation Advisory Centre (IMAC) hosted the 2nd New Zealand Influenza Symposium (NZiS) in November 2015. International and national participants discussed current issues in influenza management and prevention. Experts in the field presented data from recent studies and discussed the ecology of influenza viruses, epidemiology of influenza, methods of prevention and minimisation, and experiences from the 2015 seasonal influenza immunisation campaign. The symposium concluded that although much progress in this field has been made, many areas for future research remain.

Early Outbreak of 2009 Influenza A (H1N1) in Mexico Prior to Identification of pH1N1 Virus

Science.gov (United States)

Hsieh, Ying-Hen; Ma, Stefan; Velasco Hernandez, Jorge X.; Lee, Vernon J.; Lim, Wei Yen

2011-01-01

Background In the aftermath of the global spread of 2009 influenza A (pH1N1) virus, still very little is known of the early stages of the outbreak in Mexico during the early months of the year, before the virus was identified. Methodology/Main Findings We fit a simple mathematical model, the Richards model, to the number of excess laboratory-confirmed influenza cases in Mexico and Mexico City during the first 15 weeks in 2009 over the average influenza case number of the previous five baseline years of 2004-2008 during the same period to ascertain the turning point (or the peak incidence) of a wave of early influenza infections, and to estimate the transmissibility of the virus during these early months in terms of its basic reproduction number. The results indicate that there may have been an early epidemic in Mexico City as well as in all of Mexico during February/March. Based on excess influenza cases, the estimated basic reproduction number R0 for the early outbreak was 1.59 (0.55 to 2.62) for Mexico City during weeks 5–9, and 1.25 (0.76, 1.74) for all of Mexico during weeks 5–14. Conclusions We established the existence of an early epidemic in Mexico City and in all of Mexico during February/March utilizing the routine influenza surveillance data, although the location of seeding is unknown. Moreover, estimates of R0 as well as the time of peak incidence (the turning point) for Mexico City and all of Mexico indicate that the early epidemic in Mexico City in February/March had been more transmissible (larger R0) and peaked earlier than the rest of the country. Our conclusion lends support to the possibility that the virus could have already spread to other continents prior to the identification of the virus and the reporting of lab-confirmed pH1N1 cases in North America in April. PMID:21909366

Epidemiology, Evolution, and Recent Outbreaks of Avian Influenza Virus in China.

Science.gov (United States)

Su, Shuo; Bi, Yuhai; Wong, Gary; Gray, Gregory C; Gao, George F; Li, Shoujun

2015-09-01

Novel reassortants of H7N9, H10N8, and H5N6 avian influenza viruses (AIVs) are currently circulating in China's poultry flocks, occasionally infecting humans and other mammals. Combined with the sometimes enzootic H5N1 and H9N2 strains, this cauldron of genetically diverse AIVs pose significant risks to public health. Here, we review the epidemiology, evolution, and recent outbreaks of AIVs in China, discuss reasons behind the recent increase in the emergence of novel AIVs, and identify warning signs which may point to the emergence of a potentially virulent and highly transmissible AIV to humans. This review will be useful to authorities who consider options for the detection and control of AIV transmission in animals and humans, with the goal of preventing future epidemics and pandemics. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Evaluation of outbreak detection performance using multi-stream syndromic surveillance for influenza-like illness in rural Hubei Province, China: a temporal simulation model based on healthcare-seeking behaviors.

Science.gov (United States)

Fan, Yunzhou; Wang, Ying; Jiang, Hongbo; Yang, Wenwen; Yu, Miao; Yan, Weirong; Diwan, Vinod K; Xu, Biao; Dong, Hengjin; Palm, Lars; Nie, Shaofa

2014-01-01

Syndromic surveillance promotes the early detection of diseases outbreaks. Although syndromic surveillance has increased in developing countries, performance on outbreak detection, particularly in cases of multi-stream surveillance, has scarcely been evaluated in rural areas. This study introduces a temporal simulation model based on healthcare-seeking behaviors to evaluate the performance of multi-stream syndromic surveillance for influenza-like illness. Data were obtained in six towns of rural Hubei Province, China, from April 2012 to June 2013. A Susceptible-Exposed-Infectious-Recovered model generated 27 scenarios of simulated influenza A (H1N1) outbreaks, which were converted into corresponding simulated syndromic datasets through the healthcare-behaviors model. We then superimposed converted syndromic datasets onto the baselines obtained to create the testing datasets. Outbreak performance of single-stream surveillance of clinic visit, frequency of over the counter drug purchases, school absenteeism, and multi-stream surveillance of their combinations were evaluated using receiver operating characteristic curves and activity monitoring operation curves. In the six towns examined, clinic visit surveillance and school absenteeism surveillance exhibited superior performances of outbreak detection than over the counter drug purchase frequency surveillance; the performance of multi-stream surveillance was preferable to signal-stream surveillance, particularly at low specificity (Sp performance of multi-stream surveillance.

H5N2 Highly Pathogenic Avian Influenza Viruses from the US 2014-2015 outbreak have an unusually long pre-clinical period in turkeys.

Science.gov (United States)

Spackman, Erica; Pantin-Jackwood, Mary J; Kapczynski, Darrell R; Swayne, David E; Suarez, David L

2016-11-22

From December 2014 through June 2015, the US experienced the most costly highly pathogenic avian influenza (HPAI) outbreak to date. Most cases in commercial poultry were caused by an H5N2 strain which was a reassortant with 5 Eurasian lineage genes, including a clade 2.3.4.4 goose/Guangdong/1996 lineage hemagglutinin, and 3 genes from North American wild waterfowl low pathogenicity avian influenza viruses. The outbreak primarily affected turkeys and table-egg layer type chickens. Three isolates were selected for characterization in turkeys: the US index isolate from December 2014 (A/northern pintail/WA/40964/2014), and two poultry isolates from April 2015 (A/chicken/IA/13388/2015 and A/turkey/MN/12528/2015). Four week old broad-breasted white turkeys were inoculated with one of three doses (10 2 , 10 4 or 10 6 50% egg infectious doses [EID 50 ] per bird) of each of the isolates to evaluate infectious dose and pathogenesis. The mean bird infectious dose of A/northern pintail/WA/40964/2014 and A/turkey/MN/12528/2015 was 10 5 EID 50 per bird, but was 10 3 EID 50 per bird for A/chicken/IA/13388/2015, suggesting the latter had greater adaptation to gallinaceous birds. All three isolates had unusually long mean death time of 5.3-5.9 days post challenge, and the primary clinical signs were severe lethargy and neurological signs which started no more than 24 h before death (the average pre-clinical period was 4 days). Infected turkeys also shed high levels of virus by both the oropharyngeal and cloacal routes. The unusually long mean death times, high levels of virus in feces, and increased adaptation of the later viruses may have contributed to the rapid spread of the virus during the peak of the outbreak.

Maternal and fetal recovery after severe respiratory failure due to influenza

DEFF Research Database (Denmark)

Madsen, Kristine; Strange, Ditte Gry; Hedegaard, Morten

2013-01-01

During pregnancy women are at increased risk of severe complications to influenza infection, including death of mother or fetus, especially if chronic comorbid medical conditions such as diabetes mellitus are present.......During pregnancy women are at increased risk of severe complications to influenza infection, including death of mother or fetus, especially if chronic comorbid medical conditions such as diabetes mellitus are present....

Influenza Pandemic Infrastructure Response in Thailand

Centers for Disease Control (CDC) Podcasts

2009-03-05

Influenza viruses change antigenic properties, or drift, every year and they create seasonal outbreaks. Occasionally, influenza viruses change in a major way, called a “shift." If an influenza virus shifts, the entire human population is susceptible to the new influenza virus, creating the potential for a pandemic. On this podcast, CDC's Dr. Scott Dowell discusses responding to an influenza pandemic.  Created: 3/5/2009 by Emerging Infectious Diseases.   Date Released: 3/5/2009.

Novel measurement of spreading pattern of influenza epidemic by using weighted standard distance method: retrospective spatial statistical study of influenza, Japan, 1999-2009.

Science.gov (United States)

Shobugawa, Yugo; Wiafe, Seth A; Saito, Reiko; Suzuki, Tsubasa; Inaida, Shinako; Taniguchi, Kiyosu; Suzuki, Hiroshi

2012-06-19

Annual influenza epidemics occur worldwide resulting in considerable morbidity and mortality. Spreading pattern of influenza is not well understood because it is often hampered by the quality of surveillance data that limits the reliability of analysis. In Japan, influenza is reported on a weekly basis from 5,000 hospitals and clinics nationwide under the scheme of the National Infectious Disease Surveillance. The collected data are available to the public as weekly reports which were summarized into number of patient visits per hospital or clinic in each of the 47 prefectures. From this surveillance data, we analyzed the spatial spreading patterns of influenza epidemics using weekly weighted standard distance (WSD) from the 1999/2000 through 2008/2009 influenza seasons in Japan. WSD is a single numerical value representing the spatial compactness of influenza outbreak, which is small in case of clustered distribution and large in case of dispersed distribution. We demonstrated that the weekly WSD value or the measure of spatial compactness of the distribution of reported influenza cases, decreased to its lowest value before each epidemic peak in nine out of ten seasons analyzed. The duration between the lowest WSD week and the peak week of influenza cases ranged from minus one week to twenty weeks. The duration showed significant negative association with the proportion of influenza A/H3N2 cases in early phase of each outbreak (correlation coefficient was -0.75, P = 0.012) and significant positive association with the proportion of influenza B cases in the early phase (correlation coefficient was 0.64, P = 0.045), but positively correlated with the proportion of influenza A/H1N1 strain cases (statistically not significant). It is assumed that the lowest WSD values just before influenza peaks are due to local outbreak which results in small standard distance values. As influenza cases disperse nationwide and an epidemic reaches its peak, WSD value changed to be a

The effect of school dismissal on rates of influenza-like illness in New York City schools during the spring 2009 novel H1N1 outbreak.

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Egger, Joseph R; Konty, Kevin J; Wilson, Elisha; Karpati, Adam; Matte, Thomas; Weiss, Don; Barbot, Oxiris

2012-03-01

The effects of individual school dismissal on influenza transmission have not been well studied. During the spring 2009 novel H1N1 outbreak, New York City implemented an individual school dismissal policy intended to limit influenza transmission at schools with high rates of influenza-like illness (ILI). Active disease surveillance data collected by the New York City Health Department on rates of ILI in schools were used to evaluate the impact. Sixty-four schools that met the Health Department's criteria for considering dismissal were included in the analysis. Twenty-four schools that met criteria subsequently dismissed all classes for approximately 1 school week. A regression model was fit to these data, estimating the effect of school dismissal on rates of in-school ILI following reconvening, adjusting for potential confounders. The model estimated that, on average, school dismissal reduced the rate of ILI by 7.1% over the entire average outbreak period. However, a large proportion of in-school ILI occurred before dismissal criteria were met. A separate model estimated that school absenteeism rates were not significantly affected by dismissal. Results suggest that individual school dismissal could be considered in situations where schools have a disproportionate number of high-risk students or may be unable to implement recommended preventive or infection control measures. Future work should focus on developing more sensitive indicators of early outbreak detection in schools and evaluating the impact of school dismissal on community transmission. © 2012, American School Health Association.

The highly pathogenic avian influenza A (H7N7) virus epidemic in the Netherlands in 2003 - lessons learned from the first five outbreaks

NARCIS (Netherlands)

Elbers, A.R.W.; Fabri, T.; Vries, T.S.; Wit, de J.J.; Pijpers, A.; Koch, G.

2004-01-01

Clinical signs and gross lesions observed in poultry submitted for postmortem examination (PME) from the first five infected poultry flocks preceding the detection of the primary outbreak of highly pathogenic avian influenza (HPAI) of subtype H7N7 during the 2003 epidemic in the Netherlands are

Societal and economic consequences of influenza.

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Piedra, Pedro A

2008-10-01

High rates of vaccination coverage for preschool and school-aged children can reduce morbidity and mortality related to influenza outbreak. More focused and effective influenza prevention strategies are necessary to improve quality of life and to limit the burden of flu complications.

Novel measurement of spreading pattern of influenza epidemic by using weighted standard distance method: retrospective spatial statistical study of influenza, Japan, 1999–2009

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Shobugawa Yugo

2012-06-01

Full Text Available Abstract Background Annual influenza epidemics occur worldwide resulting in considerable morbidity and mortality. Spreading pattern of influenza is not well understood because it is often hampered by the quality of surveillance data that limits the reliability of analysis. In Japan, influenza is reported on a weekly basis from 5,000 hospitals and clinics nationwide under the scheme of the National Infectious Disease Surveillance. The collected data are available to the public as weekly reports which were summarized into number of patient visits per hospital or clinic in each of the 47 prefectures. From this surveillance data, we analyzed the spatial spreading patterns of influenza epidemics using weekly weighted standard distance (WSD from the 1999/2000 through 2008/2009 influenza seasons in Japan. WSD is a single numerical value representing the spatial compactness of influenza outbreak, which is small in case of clustered distribution and large in case of dispersed distribution. Results We demonstrated that the weekly WSD value or the measure of spatial compactness of the distribution of reported influenza cases, decreased to its lowest value before each epidemic peak in nine out of ten seasons analyzed. The duration between the lowest WSD week and the peak week of influenza cases ranged from minus one week to twenty weeks. The duration showed significant negative association with the proportion of influenza A/H3N2 cases in early phase of each outbreak (correlation coefficient was −0.75, P = 0.012 and significant positive association with the proportion of influenza B cases in the early phase (correlation coefficient was 0.64, P = 0.045, but positively correlated with the proportion of influenza A/H1N1 strain cases (statistically not significant. It is assumed that the lowest WSD values just before influenza peaks are due to local outbreak which results in small standard distance values. As influenza cases disperse nationwide and an

Novel measurement of spreading pattern of influenza epidemic by using weighted standard distance method: retrospective spatial statistical study of influenza, Japan, 1999–2009

Science.gov (United States)

2012-01-01

Background Annual influenza epidemics occur worldwide resulting in considerable morbidity and mortality. Spreading pattern of influenza is not well understood because it is often hampered by the quality of surveillance data that limits the reliability of analysis. In Japan, influenza is reported on a weekly basis from 5,000 hospitals and clinics nationwide under the scheme of the National Infectious Disease Surveillance. The collected data are available to the public as weekly reports which were summarized into number of patient visits per hospital or clinic in each of the 47 prefectures. From this surveillance data, we analyzed the spatial spreading patterns of influenza epidemics using weekly weighted standard distance (WSD) from the 1999/2000 through 2008/2009 influenza seasons in Japan. WSD is a single numerical value representing the spatial compactness of influenza outbreak, which is small in case of clustered distribution and large in case of dispersed distribution. Results We demonstrated that the weekly WSD value or the measure of spatial compactness of the distribution of reported influenza cases, decreased to its lowest value before each epidemic peak in nine out of ten seasons analyzed. The duration between the lowest WSD week and the peak week of influenza cases ranged from minus one week to twenty weeks. The duration showed significant negative association with the proportion of influenza A/H3N2 cases in early phase of each outbreak (correlation coefficient was −0.75, P = 0.012) and significant positive association with the proportion of influenza B cases in the early phase (correlation coefficient was 0.64, P = 0.045), but positively correlated with the proportion of influenza A/H1N1 strain cases (statistically not significant). It is assumed that the lowest WSD values just before influenza peaks are due to local outbreak which results in small standard distance values. As influenza cases disperse nationwide and an epidemic reaches its peak

Antigen-specific H1N1 influenza antibody responses in acute respiratory tract infections and their relation to influenza infection and disease course.

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Haran, John Patrick; Hoaglin, David C; Chen, Huaiqing; Boyer, Edward W; Lu, Shan

2014-08-01

Early antibody responses to influenza infection are important in both clearance of virus and fighting the disease. Acute influenza antibody titers directed toward H1-antigens and their relation to infection type and patient outcomes have not been well investigated. Using hemagglutination inhibition (HI) assays, we aimed to characterize the H1-specific antibody titers in patients with influenza infection or another respiratory infection before and after the H1N1-pandemic influenza outbreak. Among patients with acute influenza infection we related duration of illness, severity of symptoms, and need for hospitalization to antibody titers. There were 134 adult patients (average age 34.7) who presented to an urban academic emergency department (ED) from October through March during the 2008-2011 influenza seasons with symptoms of fever and a cough. Nasal aspirates were tested by viral culture, and peripheral blood serum was run in seven H1-subtype HI assays. Acutely infected influenza patients had markedly lower antibody titers for six of the seven pseudotype viruses. For the average over the seven titers (log units, base 2) their mean was 7.24 (95% CI 6.88, 7.61) compared with 8.60 (95% CI 8.27, 8.92) among patients who had a non-influenza respiratory illness, pinfection, titers of some antibodies correlated with severity of symptoms and with total duration of illness (pacute respiratory infections, lower concentrations of H1-influenza-specific antibodies were associated with influenza infection. Among influenza-infected patients, higher antibody titers were present in patients with a longer duration of illness and with higher severity-of-symptom scores. Copyright © 2014 Elsevier B.V. All rights reserved.

Genetic Reassortment Among the Influenza Viruses (Avian Influenza, Human Influenza and Swine Influenza in Pigs

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Dyah Ayu Hewajuli

2012-12-01

Full Text Available Influenza A virus is a hazardous virus and harm to respiratory tract. The virus infect birds, pigs, horses, dogs, mammals and humans. Pigs are important hosts in ecology of the influenza virus because they have two receptors, namely NeuAc 2,3Gal and NeuAc 2,6Gal which make the pigs are sensitive to infection of influenza virus from birds and humans and genetic reassortment can be occurred. Classical swine influenza H1N1 viruses had been circulated in pigs in North America and other countries for 80 years. In 1998, triple reassortant H3N2 swine influenza viruses that contains genes of human influenza A virus (H3N2, swine influenza virus (H1N1 and avian influenza are reported as cause an outbreaks in pigs in North America. Furthermore, the circulation of triple reassortant H3N2 swine influenza virus resulting reassortant H1N1 swine influenza and reassortant H1N2 swine influenza viruses cause infection in humans. Humans who were infected by triple reassortant swine influenza A virus (H1N1 usually made direct contact with pigs. Although without any clinical symptoms, pigs that are infected by triple reassortant swine influenza A (H1N1 can transmit infection to the humans around them. In June 2009, WHO declared that pandemic influenza of reassortant H1N1 influenza A virus (novel H1N1 has reached phase 6. In Indonesia until 2009, there were 1005 people were infected by H1N1 influenza A and 5 of them died. Novel H1N1 and H5N1 viruses have been circulated in humans and pigs in Indonesia. H5N1 reassortant and H1N1 viruses or the seasonal flu may could arise because of genetic reassortment between avian influenza and humans influenza viruses that infect pigs together.

Methods for molecular surveillance of influenza

OpenAIRE

Wang, Ruixue; Taubenberger, Jeffery K

2010-01-01

Molecular-based techniques for detecting influenza viruses have become an integral component of human and animal surveillance programs in the last two decades. The recent pandemic of the swine-origin influenza A virus (H1N1) and the continuing circulation of highly pathogenic avian influenza A virus (H5N1) further stress the need for rapid and accurate identification and subtyping of influenza viruses for surveillance, outbreak management, diagnosis and treatment. There has been remarkable pr...

Characteristics of diagnostic tests used in the 2002 low-pathogenicity avian influenza H7N2 outbreak in Virginia.

Science.gov (United States)

Elvinger, François; Akey, Bruce L; Senne, Dennis A; Pierson, F William; Porter-Spalding, Barbara A; Spackman, Erica; Suarez, David L

2007-07-01

An outbreak of low-pathogenicity avian influenza (LPAI) H7N2 occurred in 2002 in the Shenandoah Valley, a high-density poultry production region in Virginia. Infected flocks were identified through a combination of observation of clinical signs and laboratory diagnostic tests designed to detect avian influenza (AI) antibodies, virus, or H7-specific RNA. In this report, fitness for purpose of 3 virus/RNA detection assays used during the outbreak was examined: 1) antigen capture enzyme immunoassay (AC-EIA), 2) real-time reverse transcription polymerase chain reaction (RRT-PCR), and 3) virus isolation (VI). Results from testing 762 turkey and 2,216 chicken tracheal swab pooled specimens were analyzed to determine diagnostic sensitivities and specificities of these tests under field conditions using Bayesian techniques for validation of diagnostic tests in the absence of a "gold standard." Diagnostic sensitivities (with 95% probability intervals) in turkeys of AC-EIA and RRT-PCR, in reference to VI, were 65.9 (50.6; 81.3)% and 85.1 (71.9; 95.7)% and of VI 92.9 (78.0; 98.8)% in reference to AC-EIA or 88.7 (76.0; 97.2)% in reference to RRT-PCR; in chickens, diagnostic sensitivities were 75.1 (45.6; 94.2)%, 86.3 (65.9; 97.1)%, and 86.2 (65.8; 97.1)% or 86.3 (66.4; 97.2)%, respectively. Specificities were 99.1 (97.9; 99.8)%, 98.9 (98.0; 99.5)%, and 98.6 (97.4; 99.4)% or 98.8 (97.8; 99.5)% in turkeys and between 99.25% and 99.27% with probability intervals of approximately +/-0.4% for all tests in chickens. Simultaneous use of AC-EIA and RRT-PCR contributed significantly to the rapid control of the outbreak, but the AI RRT-PCR assay with >85% sensitivity and approximately 99% specificity, combined with relatively low cost and fast turnaround, could be used as the sole diagnostic test in outbreaks of LPAI.

Incidence of influenza-like illness and severe acute respiratory infection during three influenza seasons in Bangladesh, 2008–2010

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Alamgir, ASM; Rahman, Mustafizur; Homaira, Nusrat; Sohel, Badrul Munir; Sharker, MA Yushuf; Zaman, Rashid Uz; Dee, Jacob; Gurley, Emily S; Al Mamun, Abdullah; Mah-E-Muneer, Syeda; Fry, Alicia M; Widdowson, Marc-Alain; Bresee, Joseph; Lindstrom, Stephen; Azim, Tasnim; Brooks, Abdullah; Podder, Goutam; Hossain, M Jahangir; Rahman, Mahmudur; Luby, Stephen P

2012-01-01

Abstract Objective To determine how much influenza contributes to severe acute respiratory illness (SARI), a leading cause of death in children, among people of all ages in Bangladesh. Methods Physicians obtained nasal and throat swabs to test for influenza virus from patients who were hospitalized within 7 days of the onset of severe acute respiratory infection (SARI) or who consulted as outpatients for influenza-like illness (ILI). A community health care utilization survey was conducted to determine the proportion of hospital catchment area residents who sought care at study hospitals and calculate the incidence of influenza using this denominator. Findings The estimated incidence of SARI associated with influenza in children < 5 years old was 6.7 (95% confidence interval, CI: 0–18.3); 4.4 (95% CI: 0–13.4) and 6.5 per 1000 person–years (95% CI: 0–8.3/1000) during the 2008, 2009 and 2010 influenza seasons, respectively. The incidence of SARI in people aged ≥ 5 years was 1.1 (95% CI: 0.4–2.0) and 1.3 (95% CI: 0.5–2.2) per 10 000 person–years during 2009 and 2010, respectively. The incidence of medically attended, laboratory-confirmed seasonal influenza in outpatients with ILI was 10 (95% CI: 8–14), 6.6 (95% CI: 5–9) and 17 per 100 person–years (95% CI: 13–22) during the 2008, 2009 and 2010 influenza seasons, respectively. Conclusion Influenza-like illness is a frequent cause of consultation in the outpatient setting in Bangladesh. Children aged less than 5 years are hospitalized for influenza in greater proportions than children in other age groups. PMID:22271960

DAMPs and influenza virus infection in ageing.

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Samy, Ramar Perumal; Lim, Lina H K

2015-11-01

Influenza A virus (IAV) is a serious global health problem worldwide due to frequent and severe outbreaks. IAV causes significant morbidity and mortality in the elderly population, due to the ineffectiveness of the vaccine and the alteration of T cell immunity with ageing. The cellular and molecular link between ageing and virus infection is unclear and it is possible that damage associated molecular patterns (DAMPs) may play a role in the raised severity and susceptibility of virus infections in the elderly. DAMPs which are released from damaged cells following activation, injury or cell death can activate the immune response through the stimulation of the inflammasome through several types of receptors found on the plasma membrane, inside endosomes after endocytosis as well as in the cytosol. In this review, the detriment in the immune system during ageing and the links between influenza virus infection and ageing will be discussed. In addition, the role of DAMPs such as HMGB1 and S100/Annexin in ageing, and the enhanced morbidity and mortality to severe influenza infection in ageing will be highlighted. Copyright © 2015 Elsevier B.V. All rights reserved.

[In silico evaluation of an aviar influenza AH5N1 virus outbreak with human to human transmission: effects of sanitary measures in Valencia, Venezuela, 2012].

Science.gov (United States)

Reggeti, Mariana; Romero, Emilse; Eblen-Zajjur, Antonio

2016-06-01

There is a risk for an avian influenza AH5N1 virus pandemia. To estimate the magnitude and impact of an AH5N1 pandemic in areas of Latin-America in order to design interventions and to reduce morbidity-mortality. The InfluSim program was used to simulate a highly pathogenic AH5N1 aviar virus epidemic outbreak with human to human transmission in Valencia, Venezuela. We estimated the day of maximal number of cases, number of moderately and severely ill patients, exposed individuals, deaths and associated costs for 5 different interventions: absence of any intervention; implementation of antiviral treatment; reduction of 20% in population general contacts; closure of 20% of educational institutions; and reduction of 50% in massive public gatherings. Simulation parameters used were: population: 829.856 persons, infection risk 6-47%, contagiousness Index Rh o 2,5; relative contagiousness 90%, overall lethality 64,1% and, costs according to the official basic budget. For an outbreak lasting 200 days direct and indirect deaths by intervention strategies would be: 29,907; 29,900; 9,701; 29,295 and 14,752. Costs would follow a similar trend. Reduction of 20% in general population contacts results in a significant reduction of up to 68% of cases. The outbreak would collapse the health care system. Antiviral treatment would not be efficient during the outbreak. Interpersonal contact reduction proved to be the best sanitary measure to control an AH5N1 theoretical epidemic outbreak.

Key transmission parameters of an institutional outbreak during the 1918 influenza pandemic estimated by mathematical modelling

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Nelson Peter

2006-11-01

Full Text Available Abstract Aim To estimate the key transmission parameters associated with an outbreak of pandemic influenza in an institutional setting (New Zealand 1918. Methods Historical morbidity and mortality data were obtained from the report of the medical officer for a large military camp. A susceptible-exposed-infectious-recovered epidemiological model was solved numerically to find a range of best-fit estimates for key epidemic parameters and an incidence curve. Mortality data were subsequently modelled by performing a convolution of incidence distribution with a best-fit incidence-mortality lag distribution. Results Basic reproduction number (R0 values for three possible scenarios ranged between 1.3, and 3.1, and corresponding average latent period and infectious period estimates ranged between 0.7 and 1.3 days, and 0.2 and 0.3 days respectively. The mean and median best-estimate incidence-mortality lag periods were 6.9 and 6.6 days respectively. This delay is consistent with secondary bacterial pneumonia being a relatively important cause of death in this predominantly young male population. Conclusion These R0 estimates are broadly consistent with others made for the 1918 influenza pandemic and are not particularly large relative to some other infectious diseases. This finding suggests that if a novel influenza strain of similar virulence emerged then it could potentially be controlled through the prompt use of major public health measures.

Influenza in long-term care facilities.

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Lansbury, Louise E; Brown, Caroline S; Nguyen-Van-Tam, Jonathan S

2017-09-01

Long-term care facility environments and the vulnerability of their residents provide a setting conducive to the rapid spread of influenza virus and other respiratory pathogens. Infections may be introduced by staff, visitors or new or transferred residents, and outbreaks of influenza in such settings can have devastating consequences for individuals, as well as placing extra strain on health services. As the population ages over the coming decades, increased provision of such facilities seems likely. The need for robust infection prevention and control practices will therefore remain of paramount importance if the impact of outbreaks is to be minimised. In this review, we discuss the nature of the problem of influenza in long-term care facilities, and approaches to preventive and control measures, including vaccination of residents and staff, and the use of antiviral drugs for treatment and prophylaxis, based on currently available evidence. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Universal immunity to influenza must outwit immune evasion

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Sergio Manuel Quinones-Parra

2014-06-01

Full Text Available Although an influenza vaccine has been available for 70 years, influenza virus still causes seasonal epidemics and worldwide pandemics. Currently available vaccines elicit strain-specific antibody responses to the surface haemagglutinin (HA and neuraminidase (NA proteins, but these can be ineffective against serologically-distinct viral variants and novel subtypes. Thus, there is a need for cross-protective or universal influenza vaccines to overcome the necessity for annual immunisation against seasonal influenza and to provide immunity to reduce the severity of infection with pandemic or outbreak viruses. It is well established that natural influenza infection can provide cross-reactive immunity that can reduce the impact of infection with distinct influenza type A strains and subtypes, including H1N1, H3N2, H2N2, H5N1 and H7N9. The key to generating universal influenza immunity via vaccination is to target functionally-conserved regions of the virus, which include epitopes on the internal proteins for cross-reactive T cell immunity or on the HA stem for broadly reactive antibody responses. In the wake of the 2009 H1N1 pandemic, broadly neutralizing antibodies have been characterized and isolated from convalescent and vaccinated individuals, inspiring development of new vaccination techniques to elicit such responses. Induction of influenza-specific T cell responses through vaccination has also been examined in clinical trials. Strong evidence is available from human and animal models of influenza to show that established influenza-specific T cell memory can reduce viral shedding and symptom severity. However, the published evidence also shows that CD8+ T cells can efficiently select immune escape mutants early after influenza virus infection. Here, we discuss universal immunity to influenza viruses mediated by both cross-reactive T cells and antibodies, the mechanisms of immune evasion in influenza, and how to counteract commonly occurring

Network information analysis reveals risk perception transmission in a behaviour-influenza dynamics system.

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Liao, C-M; You, S-H; Cheng, Y-H

2015-01-01

Influenza poses a significant public health burden worldwide. Understanding how and to what extent people would change their behaviour in response to influenza outbreaks is critical for formulating public health policies. We incorporated the information-theoretic framework into a behaviour-influenza (BI) transmission dynamics system in order to understand the effects of individual behavioural change on influenza epidemics. We showed that information transmission of risk perception played a crucial role in the spread of health-seeking behaviour throughout influenza epidemics. Here a network BI model provides a new approach for understanding the risk perception spread and human behavioural change during disease outbreaks. Our study allows simultaneous consideration of epidemiological, psychological, and social factors as predictors of individual perception rates in behaviour-disease transmission systems. We suggest that a monitoring system with precise information on risk perception should be constructed to effectively promote health behaviours in preparation for emerging disease outbreaks.

Genetic Analyses of an H3N8 Influenza Virus Isolate, Causative Strain of the Outbreak of Equine Influenza at the Kanazawa Racecourse in Japan in 2007.

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Ito, Mika; Nagai, Makoto; Hayakawa, Yuji; Komae, Hirofumi; Murakami, Naruto; Yotsuya, Syouichi; Asakura, Shingo; Sakoda, Yoshihiro; Kida, Hiroshi

2008-09-01

In August 2007, an outbreak of equine influenza occurred among vaccinated racehorses with Japanese commercial equine influenza vaccine at Kanazawa Racecourse in Ishikawa prefecture in Japan. Apparent symptoms were pyrexia (38.2-41.0 degrees C) and nasal discharge with or without coughing, although approximately half of the infected horses were subclinical. All horses had been shot with a vaccine that contained two inactivated H3N8 influenza virus strains [A/equine/La Plata/93 (La Plata/93) of American lineage and A/equine/Avesta/93 (Avesta/93) of European lineage] and an H7N7 strain (A/equine/Newmarket/1/77). Influenza virus, A/equine/Kanazawa/1/2007 (H3N8) (Kanazawa/07), was isolated from one of the nasal swab samples of diseased horses. Phylogenetic analysis indicated that Kanazawa/07 was classified into the American sublineage Florida. In addition, four amino acid substitutions were found in the antigenic sites B and E in the HA1 subunit protein of Kanazawa/07 in comparison with that of La Plata/93. Hemagglutination-inhibition (HI) test using 16 serum samples from recovering horses revealed that 1.4- to 8-fold difference in titers between Kanazawa/07 and either of the vaccine strains. The present findings suggest that Japanese commercial inactivated vaccine contributed to reducing the morbidity rate and manifestation of the clinical signs of horses infected with Kanazawa/07 that may be antigenically different from the vaccine strains.

Influenza serological studies to inform public health action: best practices to optimise timing, quality and reporting.

Science.gov (United States)

Laurie, Karen L; Huston, Patricia; Riley, Steven; Katz, Jacqueline M; Willison, Donald J; Tam, John S; Mounts, Anthony W; Hoschler, Katja; Miller, Elizabeth; Vandemaele, Kaat; Broberg, Eeva; Van Kerkhove, Maria D; Nicoll, Angus

2013-03-01

Serological studies can detect infection with a novel influenza virus in the absence of symptoms or positive virology, providing useful information on infection that goes beyond the estimates from epidemiological, clinical and virological data. During the 2009 A(H1N1) pandemic, an impressive number of detailed serological studies were performed, yet the majority of serological data were available only after the first wave of infection. This limited the ability to estimate the transmissibility and severity of this novel infection, and the variability in methodology and reporting limited the ability to compare and combine the serological data.   To identify best practices for conduct and standardisation of serological studies on outbreak and pandemic influenza to inform public policy. An international meeting was held in February 2011 in Ottawa, Canada, to foster the consensus for greater standardisation of influenza serological studies. Best practices for serological investigations of influenza epidemiology include the following: classification of studies as pre-pandemic, outbreak, pandemic or inter-pandemic with a clearly identified objective; use of international serum standards for laboratory assays; cohort and cross-sectional study designs with common standards for data collection; use of serum banks to improve sampling capacity; and potential for linkage of serological, clinical and epidemiological data. Advance planning for outbreak studies would enable a rapid and coordinated response; inclusion of serological studies in pandemic plans should be considered. Optimising the quality, comparability and combinability of influenza serological studies will provide important data upon emergence of a novel or variant influenza virus to inform public health action. © 2012 Blackwell Publishing Ltd.

Newcastle disease virus-based H5 influenza vaccine protects chickens from lethal challenge with a highly pathogenic H5N2 avian influenza virus

OpenAIRE

Ma, Jingjiao; Lee, Jinhwa; Liu, Haixia; Mena, Ignacio; Davis, A. Sally; Sunwoo, Sun Young; Lang, Yuekun; Duff, Michael; Morozov, Igor; Li, Yuhao; Yang, Jianmei; García-Sastre, Adolfo; Richt, Juergen A.; Ma, Wenjun

2017-01-01

Since December 2014, Eurasian-origin, highly pathogenic avian influenza H5 viruses including H5N1, H5N2, and H5N8 subtypes (called H5Nx viruses), which belong to the H5 clade 2.3.4.4, have been detected in U.S. wild birds. Subsequently, highly pathogenic H5N2 and H5N8 viruses have caused outbreaks in U.S. domestic poultry. Vaccination is one of the most effective ways to control influenza outbreaks and protect animal and public health. Newcastle disease virus (NDV)-based influenza vaccines ha...

Evaluation of outbreak detection performance using multi-stream syndromic surveillance for influenza-like illness in rural Hubei Province, China: a temporal simulation model based on healthcare-seeking behaviors.

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Yunzhou Fan

Full Text Available BACKGROUND: Syndromic surveillance promotes the early detection of diseases outbreaks. Although syndromic surveillance has increased in developing countries, performance on outbreak detection, particularly in cases of multi-stream surveillance, has scarcely been evaluated in rural areas. OBJECTIVE: This study introduces a temporal simulation model based on healthcare-seeking behaviors to evaluate the performance of multi-stream syndromic surveillance for influenza-like illness. METHODS: Data were obtained in six towns of rural Hubei Province, China, from April 2012 to June 2013. A Susceptible-Exposed-Infectious-Recovered model generated 27 scenarios of simulated influenza A (H1N1 outbreaks, which were converted into corresponding simulated syndromic datasets through the healthcare-behaviors model. We then superimposed converted syndromic datasets onto the baselines obtained to create the testing datasets. Outbreak performance of single-stream surveillance of clinic visit, frequency of over the counter drug purchases, school absenteeism, and multi-stream surveillance of their combinations were evaluated using receiver operating characteristic curves and activity monitoring operation curves. RESULTS: In the six towns examined, clinic visit surveillance and school absenteeism surveillance exhibited superior performances of outbreak detection than over the counter drug purchase frequency surveillance; the performance of multi-stream surveillance was preferable to signal-stream surveillance, particularly at low specificity (Sp <90%. CONCLUSIONS: The temporal simulation model based on healthcare-seeking behaviors offers an accessible method for evaluating the performance of multi-stream surveillance.

Predicting Zoonotic Risk of Influenza A Viruses from Host Tropism Protein Signature Using Random Forest

OpenAIRE

Christine L. P. Eng; Joo Chuan Tong; Tin Wee Tan

2017-01-01

Influenza A viruses remain a significant health problem, especially when a novel subtype emerges from the avian population to cause severe outbreaks in humans. Zoonotic viruses arise from the animal population as a result of mutations and reassortments, giving rise to novel strains with the capability to evade the host species barrier and cause human infections. Despite progress in understanding interspecies transmission of influenza viruses, we are no closer to predicting zoonotic strains th...

Influenza-Like Illness among University Students: Symptom Severity and Duration Due to Influenza Virus Infection Compared to Other Etiologies

Science.gov (United States)

Mullins, Jocelyn; Cook, Robert; Rinaldo, Charles; Yablonsky, Eric; Hess, Rachel; Piazza, Paolo

2011-01-01

Objective: University students with influenza-like illness (ILI) were assessed to determine whether symptom severity, duration, or missed days of school or work varied according to etiology. Participants: Sixty persons presenting to a university health clinic with ILI symptoms during 3 consecutive influenza seasons completed baseline survey and…

The transmissibility of highly pathogenic avian influenza in commercial poultry in industrialised countries.

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Tini Garske

2007-04-01

Full Text Available With the increased occurrence of outbreaks of H5N1 worldwide there is concern that the virus could enter commercial poultry farms with severe economic consequences.We analyse data from four recent outbreaks of highly pathogenic avian influenza (HPAI in commercial poultry to estimate the farm-to-farm reproductive number for HPAI. The reproductive number is a key measure of the transmissibility of HPAI at the farm level because it can be used to evaluate the effectiveness of the control measures. In these outbreaks the mean farm-to-farm reproductive number prior to controls ranged from 1.1 to 2.4, with the maximum farm-based reproductive number in the range 2.2 to 3.2. Enhanced bio-security, movement restrictions and prompt isolation of the infected farms in all four outbreaks substantially reduced the reproductive number, but it remained close to the threshold value 1 necessary to ensure the disease will be eradicated.Our results show that depending on the particular situation in which an outbreak of avian influenza occurs, current controls might not be enough to eradicate the disease, and therefore a close monitoring of the outbreak is required. The method we used for estimating the reproductive number is straightforward to implement and can be used in real-time. It therefore can be a useful tool to inform policy decisions.

Does Eating Chicken Feet With Pickled Peppers Cause Avian Influenza? Observational Case Study on Chinese Social Media During the Avian Influenza A (H7N9) Outbreak.

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Chen, Bin; Shao, Jian; Liu, Kui; Cai, Gaofeng; Jiang, Zhenggang; Huang, Yuru; Gu, Hua; Jiang, Jianmin

2018-03-29

A hot topic on the relationship between a popular avian-origin food and avian influenza occurred on social media during the outbreak of the emerging avian influenza A (H7N9). The misinformation generated from this topic had caused great confusion and public concern. Our goals were to analyze the trend and contents of the relevant posts during the outbreak. We also aimed to understand the characteristics of the misinformation and to provide suggestions to reduce public misconception on social media during the emerging disease outbreak. The original microblog posts were collected from China's Sina Weibo and Tencent Weibo using a combination of keywords between April 1, 2013 and June 2, 2013. We analyzed the weekly and daily trend of the relevant posts. Content analyses were applied to categorize the posts into 4 types with unified sorting criteria. The posts' characteristics and geographic locations were also analyzed in each category. We conducted further analysis on the top 5 most popular misleading posts. A total of 1680 original microblog posts on the topic were retrieved and 341 (20.30%) of these posts were categorized as misleading messages. The number of relevant posts had not increased much during the first 2 weeks but rose to a high level in the next 2 weeks after the sudden increase in number of reported cases at the beginning of week 3. The posts under "misleading messages" occurred and increased from the beginning of week 3, but their daily posting number decreased when the daily number of posts under "refuting messages" outnumbered them. The microbloggers of the misleading posts had the lowest mean rank of followers and previous posts, but their posts had a highest mean rank of posts. The proportion of "misleading messages" in places with no reported cases was significantly higher than that in the epidemic areas (23.6% vs 13.8%). The popular misleading posts appeared to be short and consisted of personal narratives, which were easily disseminated on

Performance of clinical signs in poultry for the detection of outbreaks during the avian influenza A (H7N7) epidemic in the Netherlands in 2003

NARCIS (Netherlands)

Elbers, A.R.W.; Koch, G.; Bouma, A.

2005-01-01

The aim of this study was to make an inventory of the clinical signs of high-pathogenicity avian influenza (HPAI), to facilitate the development of an operational syndrome-reporting system (SRS) in The Netherlands as an early warning system for HPAI outbreaks. A total of 537 poultry flocks (240

Bacillus Calmette-Guérin-Induced trained immunity is not protective for experimental influenza A/Anhui/1/2013 (H7N9) infection in mice

DEFF Research Database (Denmark)

de Bree, Charlotte L.C.J.; Marijnissen, Renoud J.; Kel, Junda M.

2018-01-01

potentially lead to an influenza pandemic, which may have severe consequences due to the absence of pre-existent immunity to this strain at population level. Currently there is no influenza A (H7N9) vaccine available. Therefore, in case of a pandemic outbreak, alternative preventive approaches are needed......, ideally even independent of the type of influenza virus outbreak. Bacillus Calmette-Guérin (BCG) is known to induce strong heterologous immunological effects, and it has been shown that BCG protects against non-related infection challenges in several mouse models. BCG immunization of mice as well as human......9) challenge. Here, we show that isolated splenocytes as well as peritoneal macrophages of BCG-immunized BALB/c mice displayed a trained immunity phenotype resulting in increased innate cytokine responses upon ex vivo restimulation. However, after H7N9 infection, no significant differences were...

Severe pandemic 2009 H1N1 influenza disease due to pathogenic immune complexes

Science.gov (United States)

Monsalvo, Ana Clara; Batalle, Juan P.; Lopez, M. Florencia; Krause, Jens C.; Klemenc, Jennifer; Zea, Johanna; Maskin, Bernardo; Bugna, Jimena; Rubinstein, Carlos; Aguilar, Leandro; Dalurzo, Liliana; Libster, Romina; Savy, Vilma; Baumeister, Elsa; Aguilar, Liliana; Cabral, Graciela; Font, Julia; Solari, Liliana; Weller, Kevin P.; Johnson, Joyce; Echavarria, Marcela; Edwards, Kathryn M.; Chappell, James D.; Crowe, James E.; Williams, John V.; Melendi, Guillermina A.; Polack, Fernando P.

2010-01-01

Pandemic influenza viruses often cause severe disease in middle-aged adults without preexistent co-morbidities. The mechanism of illness associated with severe disease in this age group is not well understood1–10. Here, we demonstrate preexisting serum antibody that cross-reacts with, but does not protect against 2009 H1N1 influenza virus in middle-aged adults. Non-protective antibody is associated with immune complex(IC)-mediated disease after infection. High titers of serum antibody of low avidity for H1-2009 antigen, and low avidity pulmonary ICs against the same protein were detected in severely ill patients. Moreover, C4d deposition - a sensitive marker of complement activation mediated by ICs- was present in lung sections of fatal cases. Archived lung sections from adults with confirmed fatal influenza 1957 H2N2 infection revealed a similar mechanism of illness. These observations provide a novel biological mechanism for the unusual age distribution of severe cases during influenza pandemics. PMID:21131958

A mathematical model of avian influenza with half-saturated incidence.

Science.gov (United States)

Chong, Nyuk Sian; Tchuenche, Jean Michel; Smith, Robert J

2014-03-01

The widespread impact of avian influenza viruses not only poses risks to birds, but also to humans. The viruses spread from birds to humans and from human to human In addition, mutation in the primary strain will increase the infectiousness of avian influenza. We developed a mathematical model of avian influenza for both bird and human populations. The effect of half-saturated incidence on transmission dynamics of the disease is investigated. The half-saturation constants determine the levels at which birds and humans contract avian influenza. To prevent the spread of avian influenza, the associated half-saturation constants must be increased, especially the half-saturation constant H m for humans with mutant strain. The quantity H m plays an essential role in determining the basic reproduction number of this model. Furthermore, by decreasing the rate β m at which human-to-human mutant influenza is contracted, an outbreak can be controlled more effectively. To combat the outbreak, we propose both pharmaceutical (vaccination) and non-pharmaceutical (personal protection and isolation) control methods to reduce the transmission of avian influenza. Vaccination and personal protection will decrease β m, while isolation will increase H m. Numerical simulations demonstrate that all proposed control strategies will lead to disease eradication; however, if we only employ vaccination, it will require slightly longer to eradicate the disease than only applying non-pharmaceutical or a combination of pharmaceutical and non-pharmaceutical control methods. In conclusion, it is important to adopt a combination of control methods to fight an avian influenza outbreak.

Revision of clinical case definitions: influenza-like illness and severe acute respiratory infection

Science.gov (United States)

Qasmieh, Saba; Mounts, Anthony Wayne; Alexander, Burmaa; Besselaar, Terry; Briand, Sylvie; Brown, Caroline; Clark, Seth; Dueger, Erica; Gross, Diane; Hauge, Siri; Hirve, Siddhivinayak; Jorgensen, Pernille; Katz, Mark A; Mafi, Ali; Malik, Mamunur; McCarron, Margaret; Meerhoff, Tamara; Mori, Yuichiro; Mott, Joshua; Olivera, Maria Teresa da Costa; Ortiz, Justin R; Palekar, Rakhee; Rebelo-de-Andrade, Helena; Soetens, Loes; Yahaya, Ali Ahmed; Zhang, Wenqing; Vandemaele, Katelijn

2018-01-01

Abstract The formulation of accurate clinical case definitions is an integral part of an effective process of public health surveillance. Although such definitions should, ideally, be based on a standardized and fixed collection of defining criteria, they often require revision to reflect new knowledge of the condition involved and improvements in diagnostic testing. Optimal case definitions also need to have a balance of sensitivity and specificity that reflects their intended use. After the 2009–2010 H1N1 influenza pandemic, the World Health Organization (WHO) initiated a technical consultation on global influenza surveillance. This prompted improvements in the sensitivity and specificity of the case definition for influenza – i.e. a respiratory disease that lacks uniquely defining symptomology. The revision process not only modified the definition of influenza-like illness, to include a simplified list of the criteria shown to be most predictive of influenza infection, but also clarified the language used for the definition, to enhance interpretability. To capture severe cases of influenza that required hospitalization, a new case definition was also developed for severe acute respiratory infection in all age groups. The new definitions have been found to capture more cases without compromising specificity. Despite the challenge still posed in the clinical separation of influenza from other respiratory infections, the global use of the new WHO case definitions should help determine global trends in the characteristics and transmission of influenza viruses and the associated disease burden. PMID:29403115

Reviewing the History of Pandemic Influenza: Understanding Patterns of Emergence and Transmission

Science.gov (United States)

Saunders-Hastings, Patrick R.; Krewski, Daniel

2016-01-01

For centuries, novel strains of influenza have emerged to produce human pandemics, causing widespread illness, death, and disruption. There have been four influenza pandemics in the past hundred years. During this time, globalization processes, alongside advances in medicine and epidemiology, have altered the way these pandemics are experienced. Drawing on international case studies, this paper provides a review of the impact of past influenza pandemics, while examining the evolution of our understanding of, and response to, these viruses. This review argues that pandemic influenza is in part a consequence of human development, and highlights the importance of considering outbreaks within the context of shifting global landscapes. While progress in infectious disease prevention, control, and treatment has improved our ability to respond to such outbreaks, globalization processes relating to human behaviour, demographics, and mobility have increased the threat of pandemic emergence and accelerated global disease transmission. Preparedness planning must continue to evolve to keep pace with this heightened risk. Herein, we look to the past for insights on the pandemic experience, underlining both progress and persisting challenges. However, given the uncertain timing and severity of future pandemics, we emphasize the need for flexible policies capable of responding to change as such emergencies develop. PMID:27929449

Physician privacy concerns when disclosing patient data for public health purposes during a pandemic influenza outbreak.

Science.gov (United States)

El Emam, Khaled; Mercer, Jay; Moreau, Katherine; Grava-Gubins, Inese; Buckeridge, David; Jonker, Elizabeth

2011-06-09

Privacy concerns by providers have been a barrier to disclosing patient information for public health purposes. This is the case even for mandated notifiable disease reporting. In the context of a pandemic it has been argued that the public good should supersede an individual's right to privacy. The precise nature of these provider privacy concerns, and whether they are diluted in the context of a pandemic are not known. Our objective was to understand the privacy barriers which could potentially influence family physicians' reporting of patient-level surveillance data to public health agencies during the Fall 2009 pandemic H1N1 influenza outbreak. Thirty seven family doctors participated in a series of five focus groups between October 29-31 2009. They also completed a survey about the data they were willing to disclose to public health units. Descriptive statistics were used to summarize the amount of patient detail the participants were willing to disclose, factors that would facilitate data disclosure, and the consensus on those factors. The analysis of the qualitative data was based on grounded theory. The family doctors were reluctant to disclose patient data to public health units. This was due to concerns about the extent to which public health agencies are dependable to protect health information (trusting beliefs), and the possibility of loss due to disclosing health information (risk beliefs). We identified six specific actions that public health units can take which would affect these beliefs, and potentially increase the willingness to disclose patient information for public health purposes. The uncertainty surrounding a pandemic of a new strain of influenza has not changed the privacy concerns of physicians about disclosing patient data. It is important to address these concerns to ensure reliable reporting during future outbreaks.

Host-specific exposure and fatal neurologic disease in wild raptors from highly pathogenic avian influenza virus H5N1 during the 2006 outbreak in Germany

NARCIS (Netherlands)

J.M.A. van den Brand (Judith); O. Krone (Oliver); P.U. Wolf (Peter U.); M.W.G. van de Bildt (Marco); G. van Amerongen (Geert); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

2015-01-01

textabstractRaptors may contract highly pathogenic avian influenza virus H5N1 by hunting or scavenging infected prey. However, natural H5N1 infection in raptors is rarely reported. Therefore, we tested raptors found dead during an H5N1 outbreak in wild waterbirds in Mecklenburg-Western Pomerania,

Considerable progress in European preparations for a potential influenza pandemic.

NARCIS (Netherlands)

Paget, J.

2005-01-01

The threat of an influenza pandemic has been heightened in the past two years by outbreaks of avian influenza concentrated in South East Asia which have resulted in human deaths. So far, the avian influenza virus seems difficult to transmit from human to human, but changes in the virus genome may

Department of Defense Biological Threat Responses to the 2009-2010 H1N1 Influenza Outbreak: A Real World Exercise (Counterproliferation Paper Number 51, April 2011)

Science.gov (United States)

2011-04-01

health incidences like this, because our primary goal is preservation of the fighting force.”22 As part of previous infectious disease outbreak... Pasteur Announces Results of U.S. Clinical Trials in Adults Following One Dose of Influenza A (H1N1) Vaccine.” Sanofi Pasteur . 1 Oct. 2009. 14 Jun

Influenza virus infection among pediatric patients reporting diarrhea and influenza-like illness

Directory of Open Access Journals (Sweden)

Uyeki Timothy M

2010-01-01

Full Text Available Abstract Background Influenza is a major cause of morbidity and hospitalization among children. While less often reported in adults, gastrointestinal symptoms have been associated with influenza in children, including abdominal pain, nausea, vomiting, and diarrhea. Methods From September 2005 and April 2008, pediatric patients in Indonesia presenting with concurrent diarrhea and influenza-like illness were enrolled in a study to determine the frequency of influenza virus infection in young patients presenting with symptoms less commonly associated with an upper respiratory tract infection (URTI. Stool specimens and upper respiratory swabs were assayed for the presence of influenza virus. Results Seasonal influenza A or influenza B viral RNA was detected in 85 (11.6% upper respiratory specimens and 21 (2.9% of stool specimens. Viable influenza B virus was isolated from the stool specimen of one case. During the time of this study, human infections with highly pathogenic avian influenza A (H5N1 virus were common in the survey area. However, among 733 enrolled subjects, none had evidence of H5N1 virus infection. Conclusions The detection of influenza viral RNA and viable influenza virus from stool suggests that influenza virus may be localized in the gastrointestinal tract of children, may be associated with pediatric diarrhea and may serve as a potential mode of transmission during seasonal and epidemic influenza outbreaks.

Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico

Science.gov (United States)

Comas‐García, Andreu; García‐Sepúlveda, Christian A.; Méndez‐de Lira, José J.; Aranda‐Romo, Saray; Hernández‐Salinas, Alba E.; Noyola, Daniel E.

2010-01-01

Please cite this paper as: Comas‐García et al. (2011) Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico. Influenza and Other Respiratory Viruses 5(2), 76–82. Background  Acute respiratory infections are a leading cause of morbidity and mortality worldwide. Starting in 2009, pandemic influenza A(H1N1) 2009 virus has become one of the leading respiratory pathogens worldwide. However, the overall impact of this virus as a cause of mortality has not been clearly defined. Objectives  To determine the impact of pandemic influenza A(H1N1) 2009 on mortality in a Mexican population. Methods  We assessed the impact of pandemic influenza virus on mortality during the first and second outbreaks in San Luis Potosí, Mexico, and compared it to mortality associated with seasonal influenza and respiratory syncytial virus (RSV) during the previous winter seasons. Results  We estimated that, on average, 8·1% of all deaths that occurred during the 2003–2009 seasons were attributable to influenza and RSV. During the first pandemic influenza A(H1N1) 2009 outbreak, there was an increase in mortality in persons 5–59 years of age, but not during the second outbreak (Fall of 2009). Overall, pandemic influenza A (H1N1) 2009 outbreaks had similar effects on mortality to those associated with seasonal influenza virus epidemics. Conclusions  The impact of influenza A(H1N1) 2009 virus on mortality during the first year of the pandemic was similar to that observed for seasonal influenza. The establishment of real‐time surveillance systems capable of integrating virological, morbidity, and mortality data may result in the timely identification of outbreaks so as to allow for the institution of appropriate control measures to reduce the impact of emerging pathogens on the population. PMID:21306570

Multifocal Equine Influenza Outbreak with Vaccination Breakdown in Thoroughbred Racehorses

Directory of Open Access Journals (Sweden)

Sarah Gildea

2018-04-01

Full Text Available Equine influenza (EI outbreaks occurred on 19 premises in Ireland during 2014. Disease affected thoroughbred (TB and non-TB horses/ponies on a variety of premises including four racing yards. Initial clinical signs presented on 16 premises within a two-month period. Extensive field investigations were undertaken, and the diagnostic effectiveness of a TaqMan RT-PCR assay was demonstrated in regularly-vaccinated and sub-clinically-affected horses. Epidemiological data and repeat clinical samples were collected from 305 horses, of which 40% were reported as clinically affected, 39% were identified as confirmed cases and 11% were sub-clinically affected. Multivariable analysis demonstrated a significant association between clinical signs and age, vaccination status and number of vaccine doses received. Vaccine breakdown was identified in 31% of horses with up to date vaccination records. This included 27 horses in four different racing yards. Genetic and antigenic analysis identified causal viruses as belonging to Clade 2 of the Florida sublineage (FCL2. At the time of this study, no commercially available EI vaccine in Ireland had been updated in line with World Organisation for Animal Health (OIE recommendations to include a FCL2 virus. The findings of this study highlight the potential ease with which EI can spread among partially immune equine populations.

Estimating burden of influenza-associated influenza-like illness and severe acute respiratory infection at public healthcare facilities in Romania during the 2011/12-2015/16 influenza seasons.

Science.gov (United States)

Gefenaite, Giedre; Pistol, Adriana; Popescu, Rodica; Popovici, Odette; Ciurea, Daniel; Dolk, Christiaan; Jit, Mark; Gross, Diane

2018-01-01

Influenza is responsible for substantial morbidity and mortality, but there is limited information on reliable disease burden estimates, especially from middle-income countries in the WHO European Region. To estimate the incidence of medically attended influenza-associated influenza-like illness (ILI) and hospitalizations due to severe acute respiratory infection (SARI) presenting to public healthcare facilities in Romania. Sentinel influenza surveillance data for ILI and SARI from 2011/12-2015/16, including virological data, were used to estimate influenza-associated ILI and SARI incidence/100 000 and their 95% confidence intervals (95% CI). The overall annual incidence of ILI and influenza-associated ILI per 100 000 persons in Romania varied between 68 (95% CI: 61-76) and 318 (95% CI: 298-338) and between 23 (95% CI: 19-29) and 189 (95% CI: 149-240), respectively. The highest ILI and influenza incidence was among children aged 0-4 years. We estimated that SARI incidence per 100 000 persons was 6 (95% CI: 5-7) to 9 (95% CI: 8-10), of which 2 (95% CI: 1-2) to 3 (95% CI: 2-4) were due to influenza. Up to 0.3% of the Romanian population were annually reported with ILI, and 0.01% was hospitalized with SARI, of which as much as one-third could be explained by influenza. This evaluation was the first study estimating influenza burden in Romania. We found that during each influenza season, a substantial number of persons in Romania suffer from influenza-related ILI or are hospitalized due to influenza-associated SARI. © 2017 The World Health Organization. Influenza and Other Respiratory Viruses. Published by John Wiley & Sons Ltd.

Characteristics of a large mumps outbreak: Clinical severity, complications and association with vaccination status of mumps outbreak cases.

Science.gov (United States)

Zamir, C Stein; Schroeder, H; Shoob, H; Abramson, N; Zentner, G

2015-01-01

In recent years, large mumps outbreaks, involving mainly adolescents and young adults, have re-emerged in several countries. We investigated a large mumps outbreak, evaluated the association between mumps clinical severity (complications, hospitalization) and vaccination status (number of previous measles, mumps and rubella - MMR vaccine doses), and assessed vaccine effectiveness. The first mumps cases emerged in an ultra-orthodox boys' school in Jerusalem and were epidemiologically linked to the mumps outbreak in New York. Overall, 3130 mumps cases were notified in the Jerusalem district during September 2009-August 2011 (median age 13y, 64% males). Most cases were reported from community clinics. Patients with systemic symptoms and/or complications (419, 13.4%) were either hospitalized (n = 79) or treated in an emergency medical center (n = 340). The main complications included orchitis (3.8% males> age 12y) and meningoencephalitis (0.5%). The mumps virus genotype was G5. The distribution of previous MMR vaccine doses (n = 0,1,2) was: 24.8%, 28.3% and 46.9%, respectively. The number of previous vaccine doses was inversely associated with clinical severity. Adjusted values for MMR vaccine effectiveness against complications were estimated as 52.1% (95% CI -4 -78%) for one vaccine dose and 62.7% (95% CI 25.7-81.3%) for 2 doses. The outbreak was characterized by predominance of male students; the majority of whom had been previously vaccinated. The reported complication rate was relatively low. Vaccination status was associated with age and disease severity. The combination of limited mumps vaccine effectiveness and the specific school setting (dense learning and living conditions) probably contributed to the disease spread.

Nonpharmaceutical Interventions for Military Populations During Pandemic Influenza

Directory of Open Access Journals (Sweden)

Selim Kilic

2007-08-01

Full Text Available Influenza causes substantial illness and loss of work days among young adults, and outbreaks can affect the preparedness of military units. In an influenza pandemic, people who live in confined settings have greater risk of infection. Military trainees are at particularly high risk. Because of likely unavailability of vaccines and antiviral drugs at the start of a pandemic and for many months thereafter, nonpharmaceutical interventions may be very important. During a pandemic, it seems prudent that military public health officials employ at least several nonpharmaceutical interventions. For example frequent handwashing and respiratory hygiene/cough etiquette should be strongly encouraged among soldiers. Head-to-toe sleeping, a “no-cost” intervention should be for crowded berthing areas. Isolation of patients with influenza and quarantine of their close contacts should be employed. Masks and alcohol-based hand rubs may be employed among those at highest risk. Finally, whenever possible military planners should, reduce crowding and limit the interaction of training cohorts to reduce risk of influenza virus transmission. [TAF Prev Med Bull. 2007; 6(4: 285-290

Cell culture based production of avian influenza vaccines

NARCIS (Netherlands)

Wielink, van R.

2012-01-01

Vaccination of poultry can be used as a tool to control outbreaks of avian influenza, including that of highly pathogenic H5 and H7 strains. Influenza vaccines are traditionally produced in embryonated chicken eggs. Continuous cell lines have been suggested as an alternative substrate to produce

Viral vector-based influenza vaccines

Science.gov (United States)

de Vries, Rory D.; Rimmelzwaan, Guus F.

2016-01-01

ABSTRACT Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely production of effective vaccines that antigenically match the virus strains that cause epidemic or pandemic outbreaks. The development of game-changing vaccines that induce broadly protective immunity against a wide variety of influenza viruses is an unmet need, in which recombinant viral vectors may provide. Use of viral vectors allows the delivery of any influenza virus antigen, or derivative thereof, to the immune system, resulting in the optimal induction of virus-specific B- and T-cell responses against this antigen of choice. This systematic review discusses results obtained with vectored influenza virus vaccines and advantages and disadvantages of the currently available viral vectors. PMID:27455345

Influenza Vaccination Strategies: Comparing Inactivated and Live Attenuated Influenza Vaccines

Directory of Open Access Journals (Sweden)

Saranya Sridhar

2015-04-01

Full Text Available Influenza is a major respiratory pathogen causing annual outbreaks and occasional pandemics. Influenza vaccination is the major method of prophylaxis. Currently annual influenza vaccination is recommended for groups at high risk of complications from influenza infection such as pregnant women, young children, people with underlying disease and the elderly, along with occupational groups such a healthcare workers and farm workers. There are two main types of vaccines available: the parenteral inactivated influenza vaccine and the intranasal live attenuated influenza vaccine. The inactivated vaccines are licensed from 6 months of age and have been used for more than 50 years with a good safety profile. Inactivated vaccines are standardized according to the presence of the viral major surface glycoprotein hemagglutinin and protection is mediated by the induction of vaccine strain specific antibody responses. In contrast, the live attenuated vaccines are licensed in Europe for children from 2–17 years of age and provide a multifaceted immune response with local and systemic antibody and T cell responses but with no clear correlate of protection. Here we discuss the immunological immune responses elicited by the two vaccines and discuss future work to better define correlates of protection.

Influenza A Viruses of Human Origin in Swine, Brazil.

Science.gov (United States)

Nelson, Martha I; Schaefer, Rejane; Gava, Danielle; Cantão, Maurício Egídio; Ciacci-Zanella, Janice Reis

2015-08-01

The evolutionary origins of the influenza A(H1N1)pdm09 virus that caused the first outbreak of the 2009 pandemic in Mexico remain unclear, highlighting the lack of swine surveillance in Latin American countries. Although Brazil has one of the largest swine populations in the world, influenza was not thought to be endemic in Brazil's swine until the major outbreaks of influenza A(H1N1)pdm09 in 2009. Through phylogenetic analysis of whole-genome sequences of influenza viruses of the H1N1, H1N2, and H3N2 subtypes collected in swine in Brazil during 2009-2012, we identified multiple previously uncharacterized influenza viruses of human seasonal H1N2 and H3N2 virus origin that have circulated undetected in swine for more than a decade. Viral diversity has further increased in Brazil through reassortment between co-circulating viruses, including A(H1N1)pdm09. The circulation of multiple divergent hemagglutinin lineages challenges the design of effective cross-protective vaccines and highlights the need for additional surveillance.

Comparative community burden and severity of seasonal and pandemic influenza: results of the Flu Watch cohort study.

Science.gov (United States)

Hayward, Andrew C; Fragaszy, Ellen B; Bermingham, Alison; Wang, Lili; Copas, Andrew; Edmunds, W John; Ferguson, Neil; Goonetilleke, Nilu; Harvey, Gabrielle; Kovar, Jana; Lim, Megan S C; McMichael, Andrew; Millett, Elizabeth R C; Nguyen-Van-Tam, Jonathan S; Nazareth, Irwin; Pebody, Richard; Tabassum, Faiza; Watson, John M; Wurie, Fatima B; Johnson, Anne M; Zambon, Maria

2014-06-01

Assessment of the effect of influenza on populations, including risk of infection, illness if infected, illness severity, and consultation rates, is essential to inform future control and prevention. We aimed to compare the community burden and severity of seasonal and pandemic influenza across different age groups and study years and gain insight into the extent to which traditional surveillance underestimates this burden. Using preseason and postseason serology, weekly illness reporting, and RT-PCR identification of influenza from nasal swabs, we tracked the course of seasonal and pandemic influenza over five successive cohorts (England 2006-11; 5448 person-seasons' follow-up). We compared burden and severity of seasonal and pandemic strains. We weighted analyses to the age and regional structure of England to give nationally representative estimates. We compared symptom profiles over the first week of illness for different strains of PCR-confirmed influenza and non-influenza viruses using ordinal logistic regression with symptom severity grade as the outcome variable. Based on four-fold titre rises in strain-specific serology, on average influenza infected 18% (95% CI 16-22) of unvaccinated people each winter. Of those infected there were 69 respiratory illnesses per 100 person-influenza-seasons compared with 44 per 100 in those not infected with influenza. The age-adjusted attributable rate of illness if infected was 23 illnesses per 100 person-seasons (13-34), suggesting most influenza infections are asymptomatic. 25% (18-35) of all people with serologically confirmed infections had PCR-confirmed disease. 17% (10-26) of people with PCR-confirmed influenza had medically attended illness. These figures did not differ significantly when comparing pandemic with seasonal influenza. Of PCR-confirmed cases, people infected with the 2009 pandemic strain had markedly less severe symptoms than those infected with seasonal H3N2. Seasonal influenza and the 2009 pandemic

Virulence determinants of pandemic influenza viruses

Science.gov (United States)

Tscherne, Donna M.; García-Sastre, Adolfo

2011-01-01

Influenza A viruses cause recurrent, seasonal epidemics and occasional global pandemics with devastating levels of morbidity and mortality. The ability of influenza A viruses to adapt to various hosts and undergo reassortment events ensures constant generation of new strains with unpredictable degrees of pathogenicity, transmissibility, and pandemic potential. Currently, the combination of factors that drives the emergence of pandemic influenza is unclear, making it impossible to foresee the details of a future outbreak. Identification and characterization of influenza A virus virulence determinants may provide insight into genotypic signatures of pathogenicity as well as a more thorough understanding of the factors that give rise to pandemics. PMID:21206092

Influenza and other respiratory viruses: standardizing disease severity in surveillance and clinical trials.

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Rath, Barbara; Conrad, Tim; Myles, Puja; Alchikh, Maren; Ma, Xiaolin; Hoppe, Christian; Tief, Franziska; Chen, Xi; Obermeier, Patrick; Kisler, Bron; Schweiger, Brunhilde

2017-06-01

Influenza-Like Illness is a leading cause of hospitalization in children. Disease burden due to influenza and other respiratory viral infections is reported on a population level, but clinical scores measuring individual changes in disease severity are urgently needed. Areas covered: We present a composite clinical score allowing individual patient data analyses of disease severity based on systematic literature review and WHO-criteria for uncomplicated and complicated disease. The 22-item ViVI Disease Severity Score showed a normal distribution in a pediatric cohort of 6073 children aged 0-18 years (mean age 3.13; S.D. 3.89; range: 0 to 18.79). Expert commentary: The ViVI Score was correlated with risk of antibiotic use as well as need for hospitalization and intensive care. The ViVI Score was used to track children with influenza, respiratory syncytial virus, human metapneumovirus, human rhinovirus, and adenovirus infections and is fully compliant with regulatory data standards. The ViVI Disease Severity Score mobile application allows physicians to measure disease severity at the point-of care thereby taking clinical trials to the next level.

Epidemiologic and Economic Analyses on Highly Pathogenic Avian Influenza H5N1 in Nigeria and Egypt

NARCIS (Netherlands)

Fasina, F.O.

2015-01-01

Influenza A viruses have caused several devastating outbreaks in poultry with some zoonotic infections and deaths in humans. To control the viruses and their continuous circulation in poultry population, an understanding of the epidemiology of the viruses is needed. An evaluation of the situation of

The integrated information architecture: a pilot study approach to leveraging logistics management with regard to influenza preparedness.

Science.gov (United States)

Lin, Chinho; Lin, Chun-Mei; Yen, David C; Wu, Wu-Han

2012-02-01

Pandemic influenza is considered catastrophic to global health, with severe economic and social effects. Consequently, a strategy for the rapid deployment of essential medical supplies used for the prevention of influenza transmission and to alleviate public panic caused by the expected shortage of such supplies needs to be developed. Therefore, we employ integrated information concepts to develop a simulated influenza medical material supply system to facilitate a rapid response to such a crisis. Various scenarios are analyzed to estimate the appropriate inventory policy needed under different pandemic influenza outbreaks, and to establish a mechanism to evaluate the necessary stockpiles of medications and other requirements in the different phases of the pandemic. This study constructed a web-based decision support system framework prototype that displayed transparent data related to medical stockpiles in each district and integrated expert opinion about the best distribution of these supplies in the influenza pandemic scenarios. A data collection system was also designed to gather information through a daily VPN transmitted into one central repository for reporting and distribution purposes. This study provides timely and transparent medical supplies distribution information that can help decision makers to make the appropriate decisions under different pandemic influenza outbreaks, and also attempts to establish a mechanism of evaluating the stockpiles and requirements in the different phases of the pandemic.

Are we prepared to help low-resource communities cope with a severe influenza pandemic?

Science.gov (United States)

Starbuck, Eric S; von Bernuth, Rudolph; Bolles, Kathryn; Koepsell, Jeanne

2013-11-01

Recent research involving lab-modified H5N1 influenza viruses with increased transmissibility and the ongoing evolution of the virus in nature should remind us of the continuing importance of preparedness for a severe influenza pandemic. Current vaccine technology and antiviral supply remain inadequate, and in a severe pandemic, most low-resource communities will fail to receive adequate medical supplies. However, with suitable guidance, these communities can take appropriate actions without substantial outside resources to reduce influenza transmission and care for the ill. Such guidance should be completed, and support provided to developing countries to adapt it for their settings and prepare for implementation. © 2012 John Wiley & Sons Ltd.

Prevention of influenza at Hajj: applications for mass gatherings.

Science.gov (United States)

Haworth, Elizabeth; Barasheed, Osamah; Memish, Ziad A; Rashid, Harunor; Booy, Robert

2013-06-01

Outbreaks of infectious diseases that spread via respiratory route, e.g. influenza, are common amongst Hajj congregation in Mecca, Saudi Arabia. The Saudi Arabian authority successfully organized the Hajj 2009 amidst fear of pandemic influenza. While severe influenza A(H1N1)pdm09 was rare, the true burden of pandemic influenza at Hajj that year remains speculative. In this article we review the latest evidence on influenza control and discuss our experience of influenza and its prevention at Hajj and possible application to other mass gatherings. Depending on study design the attack rate of seasonal influenza at Hajj has ranged from 6% in polymerase chain reaction or culture confirmed studies to 38% in serological surveillance. No significant effect of influenza vaccine or the use of personal protective measures against influenza has been established from observational studies, although the uptake of the vaccine and adherence to face masks and hand hygiene has been low. In all, there is a relatively poor evidence base for control of influenza. Until better evidence is obtained, vaccination coupled with rapid antiviral treatment of symptomatic individuals remains the mainstay of prevention at Hajj and other mass gatherings. Hajj pilgrimage provides a unique opportunity to test the effectiveness of various preventive measures that require a large sample size, such as testing the efficacy of plain surgical masks against laboratory-confirmed influenza. After successful completion of a pilot trial conducted among Australian pilgrims at the 2011 Hajj, a large multinational cluster randomized controlled trial is being planned. This will require effective international collaboration.

Applying GIS and Machine Learning Methods to Twitter Data for Multiscale Surveillance of Influenza.

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Chris Allen

Full Text Available Traditional methods for monitoring influenza are haphazard and lack fine-grained details regarding the spatial and temporal dynamics of outbreaks. Twitter gives researchers and public health officials an opportunity to examine the spread of influenza in real-time and at multiple geographical scales. In this paper, we introduce an improved framework for monitoring influenza outbreaks using the social media platform Twitter. Relying upon techniques from geographic information science (GIS and data mining, Twitter messages were collected, filtered, and analyzed for the thirty most populated cities in the United States during the 2013-2014 flu season. The results of this procedure are compared with national, regional, and local flu outbreak reports, revealing a statistically significant correlation between the two data sources. The main contribution of this paper is to introduce a comprehensive data mining process that enhances previous attempts to accurately identify tweets related to influenza. Additionally, geographical information systems allow us to target, filter, and normalize Twitter messages.

[Severe Haemophilus influenzae b infection in healthy male adult

DEFF Research Database (Denmark)

Vilmar, A.C.; Gjorup, I.; David, Kim Peter

2008-01-01

Haemophilus influenzae b (Hib) can be the cause of serious infections, and is mainly observed affecting children and immuno-compromised patients. We report a case of a healthy 49-year old male with a severe Hib infection complicated by septicaemia, meningitis and anuria. The risk of invasive Hib...

Global Avian Influenza Surveillance in Wild Birds: A Strategy to Capture Viral Diversity

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Machalaba, Catherine C.; Elwood, Sarah E.; Forcella, Simona; Smith, Kristine M.; Hamilton, Keith; Jebara, Karim B.; Swayne, David E.; Webby, Richard J.; Mumford, Elizabeth; Mazet, Jonna A.K.; Gaidet, Nicolas; Daszak, Peter

2015-01-01

Wild birds play a major role in the evolution, maintenance, and spread of avian influenza viruses. However, surveillance for these viruses in wild birds is sporadic, geographically biased, and often limited to the last outbreak virus. To identify opportunities to optimize wild bird surveillance for understanding viral diversity, we reviewed responses to a World Organisation for Animal Health–administered survey, government reports to this organization, articles on Web of Knowledge, and the Influenza Research Database. At least 119 countries conducted avian influenza virus surveillance in wild birds during 2008–2013, but coordination and standardization was lacking among surveillance efforts, and most focused on limited subsets of influenza viruses. Given high financial and public health burdens of recent avian influenza outbreaks, we call for sustained, cost-effective investments in locations with high avian influenza diversity in wild birds and efforts to promote standardized sampling, testing, and reporting methods, including full-genome sequencing and sharing of isolates with the scientific community. PMID:25811221

Sialic acid tissue distribution and influenza virus tropism

OpenAIRE

Kumlin, Urban; Olofsson, Sigvard; Dimock, Ken; Arnberg, Niklas

2008-01-01

Abstract? Avian influenza A viruses exhibit a strong preference for using ?2,3?linked sialic acid as a receptor. Until recently, the presumed lack of this receptor in human airways was believed to constitute an efficient barrier to avian influenza A virus infection of humans. Recent zoonotic outbreaks of avian influenza A virus have triggered researchers to analyse tissue distribution of sialic acid in further detail. Here, we review and extend the current knowledge about sialic acid distribu...

Severe influenza cases in paediatric intensive care units in Germany during the pre-pandemic seasons 2005 to 2008

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Liese Johannes G

2011-08-01

Full Text Available Abstract Background Data on complications in children with seasonal influenza virus infection are limited. We initiated a nation-wide three-year surveillance of children who were admitted to a paediatric intensive care unit (PICU with severe seasonal influenza. Methods From October 2005 to July 2008, active surveillance was performed using an established reporting system for rare diseases (ESPED including all paediatric hospitals in Germany. Cases to be reported were hospitalized children Results Twenty severe influenza-associated cases were reported from 14 PICUs during three pre-pandemic influenza seasons (2005-2008. The median age of the patients (12 males/8 females was 7.5 years (range 0.1-15 years. None had received vaccination against influenza. In 14 (70% patients, the infection had been caused by influenza A and in five (25% by influenza B; in one child (5% the influenza type was not reported. Patients spent a median of 19 (IQR 12-38 days in the hospital and a median of 11 days (IQR 6-18 days in the PICU; 10 (50% needed mechanical ventilation. Most frequent diagnoses were influenza-associated pneumonia (60%, bronchitis/bronchiolitis (30%, encephalitis/encephalopathy (25%, secondary bacterial pneumonia (25%, and ARDS (25%. Eleven (55% children had chronic underlying medical conditions, including 8 (40% with chronic pulmonary diseases. Two influenza A- associated deaths were reported: i an 8-year old boy with pneumococcal encephalopathy following influenza infection died from cerebral edema, ii a 14-year-old boy with asthma bronchiale, cardiac malformation and Addison's disease died from cardiac and respiratory failure. For nine (45% patients, possibly permanent sequelae were reported (3 neurological, 3 pulmonary, 3 other sequelae. Conclusions Influenza-associated pneumonia and secondary bacterial infections are relevant complications of seasonal influenza in Germany. The incidence of severe influenza cases in PICUs was relatively low

[An overview on swine influenza viruses].

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Yang, Shuai; Zhu, Wen-Fei; Shu, Yue-Long

2013-05-01

Swine influenza viruses (SIVs) are respiratory pathogens of pigs. They cause both economic bur den in livestock-dependent industries and serious global public health concerns in humans. Because of their dual susceptibility to human and avian influenza viruses, pigs are recognized as intermediate hosts for genetic reassortment and interspecies transmission. Subtypes H1N1, H1N2, and H3N2 circulate in swine populations around the world, with varied origin and genetic characteristics among different continents and regions. In this review, the role of pigs in evolution of influenza A viruses, the genetic evolution of SIVs and interspecies transmission of SIVs are described. Considering the possibility that pigs might produce novel influenza viruses causing more outbreaks and pandemics, routine epidemiological surveillance of influenza viruses in pig populations is highly recommended.

Highly pathogenic avian influenza A (H5N1) virus in wildlife: diagnostics, epidemiology and molecular characteristics

NARCIS (Netherlands)

Keawcharoen, J.

2010-01-01

Since 2003, highly pathogenic avian influenza virus subtype H5N1 outbreaks have been reported in Southeast Asia causing high mortality in poultry and have also been found to cross the species barrier infecting human and other mammalian species. Thailand is one of the countries severely affected by

Infectious respiratory disease outbreaks and pregnancy: occupational health and safety concerns of Canadian nurses.

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Phillips, Karen P; O'Sullivan, Tracey L; Dow, Darcie; Amaratunga, Carol A

2011-04-01

This paper is a report of a qualitative study of emergency and critical care nurses' perceptions of occupational response and preparedness during infectious respiratory disease outbreaks including severe acute respiratory syndrome (SARS) and influenza. Healthcare workers, predominantly female, face occupational and personal challenges in their roles as first responders/first receivers. Exposure to SARS or other respiratory pathogens during pregnancy represents additional occupational risk for healthcare workers. Perceptions of occupational reproductive risk during response to infectious respiratory disease outbreaks were assessed qualitatively by five focus groups comprised of 100 Canadian nurses conducted between 2005 and 2006. Occupational health and safety issues anticipated by Canadian nurses for future infectious respiratory disease outbreaks were grouped into four major themes: (1) apprehension about occupational risks to pregnant nurses; (2) unknown pregnancy risks of anti-infective therapy/prophylaxis; (3) occupational risk communication for pregnant nurses; and (4) human resource strategies required for pregnant nurses during outbreaks. The reproductive risk perceptions voiced by Canadian nurses generally were consistent with reported case reports of pregnant women infected with SARS or emerging influenza strains. Nurses' fears of fertility risks posed by exposure to infectious agents or anti-infective therapy and prophylaxis are not well supported by the literature, with the former not biologically plausible and the latter lacking sufficient data. Reproductive risk assessments should be performed for each infectious respiratory disease outbreak to provide female healthcare workers and in particular pregnant women with guidelines regarding infection control and use of anti-infective therapy and prophylaxis.

Migration of whooper swans and outbreaks of highly pathogenic avian influenza H5N1 virus in eastern Asia.

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Newman, Scott H; Iverson, Samuel A; Takekawa, John Y; Gilbert, Martin; Prosser, Diann J; Batbayar, Nyambyar; Natsagdorj, Tseveenmyadag; Douglas, David C

2009-05-28

Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1) requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp.) has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus) with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer) and in habitats (areas of natural vegetation) where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks) at or near their breeding grounds.

Using egg production data to quantify within-flock transmission of low pathogenic avian influenza virus in commercial layer chickens

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Gonzales, J.L.; Elbers, A.R.W.; Goot, van der J.A.; Bontje, D.M.; Koch, G.; Wit, de J.J.; Stegeman, J.A.

2012-01-01

Even though low pathogenic avian influenza viruses (LPAIv) affect the poultry industry of several countries in the world, information about their transmission characteristics in poultry is sparse. Outbreak reports of LPAIv in layer chickens have described drops in egg production that appear to be

Influenza A Viruses of Human Origin in Swine, Brazil

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Schaefer, Rejane; Gava, Danielle; Cantão, Maurício Egídio; Ciacci-Zanella, Janice Reis

2015-01-01

The evolutionary origins of the influenza A(H1N1)pdm09 virus that caused the first outbreak of the 2009 pandemic in Mexico remain unclear, highlighting the lack of swine surveillance in Latin American countries. Although Brazil has one of the largest swine populations in the world, influenza was not thought to be endemic in Brazil’s swine until the major outbreaks of influenza A(H1N1)pdm09 in 2009. Through phylogenetic analysis of whole-genome sequences of influenza viruses of the H1N1, H1N2, and H3N2 subtypes collected in swine in Brazil during 2009–2012, we identified multiple previously uncharacterized influenza viruses of human seasonal H1N2 and H3N2 virus origin that have circulated undetected in swine for more than a decade. Viral diversity has further increased in Brazil through reassortment between co-circulating viruses, including A(H1N1)pdm09. The circulation of multiple divergent hemagglutinin lineages challenges the design of effective cross-protective vaccines and highlights the need for additional surveillance. PMID:26196759

Assessment of university student health literacy toward Influenza

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Marzieh Meraji

2016-12-01

Full Text Available Background and objective: Outbreak of influenza A/H1N1 become serious concern. Student in academic institutions can play effective role in prevention and control of influenza. Here paramedical faculty student health literacy toward Influenza was assessed. Methods: A cross sectional-descriptive study was conducted among 139 students in Medical Records, Physiotherapy, Radiology, Health Information Technology, Speech Therapy and Optometry discipline at paramedical faculty of Mashhad medical university in 2016. A pandemic influenza questionnaire was translated and edited. Demographic characteristics of student, level of knowledge and perception toward influenza and perception toward government and media were collected. Results: More than half of student correctly identified influenza symptoms as fever 95/1%, body ache 51/2%, cough 46/3% and headaches 43/9%.person to person transmission and contact with infected objects were recognized by 87/8% and 68/3% of student as a mode of transmission. Students Covering identified nose and mouth 87/8%, hand washing with soap and water 80/5% and throwing tissues in rubbish bin as precutions.48/6% of student believed that influenza is not fatal; despite 88/9% of student perceived influenza as serious disease. In Government and media assessment, 39% of student agreed health department and other health authorities had a good control plan, 51/4% of student agreed with transparency of necessary intervention during flu outbreak. Conclusion: This study shows that paramedical faculty student has appropriate influenza health literacy. Delivering more information about mode of transmission, high risk group and precaution intervention and playing more effective role by media is recommended. Paper Type: Research Article.

Avian influenza: the political economy of disease control in Cambodia.

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Ear, Sophal

2011-01-01

Abstract In the wake of avian flu outbreaks in 2004, Cambodia received $45 million in commitments from international donors to help combat the spread of animal and human influenza, particularly avian influenza (H5N1). How countries leverage foreign aid to address the specific needs of donors and the endemic needs of the nation is a complex and nuanced issue throughout the developing world. Cambodia is a particularly compelling study in pandemic preparedness and the management of avian influenza because of its multilayered network of competing local, national, and global needs, and because the level of aid in Cambodia represents approximately $2.65 million per human case-a disproportionately high number when compared with neighbors Vietnam and Indonesia. This paper examines how the Cambodian government has made use of animal and human influenza funds to protect (or fail to protect) its citizens and the global community. It asks how effective donor and government responses were to combating avian influenza in Cambodia, and what improvements could be made at the local and international level to help prepare for and respond to future outbreaks. Based on original interviews, a field survey of policy stakeholders, and detailed examination of Cambodia's health infrastructure and policies, the findings illustrate that while pandemic preparedness has shown improvements since 2004, new outbreaks and human fatalities accelerated in 2011, and more work needs to be done to align the specific goals of funders with the endemic needs of developing nations.

Risk of Human Infections With Highly Pathogenic H5N2 and Low Pathogenic H7N1 Avian Influenza Strains During Outbreaks in Ostriches in South Africa.

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Venter, Marietjie; Treurnicht, Florette K; Buys, Amelia; Tempia, Stefano; Samudzi, Rudo; McAnerney, Johanna; Jacobs, Charlene A; Thomas, Juno; Blumberg, Lucille

2017-09-15

Risk factors for human infection with highly pathogenic (HP) and low-pathogenic (LP) avian influenza (AI) H5N2 and H7N1 were investigated during outbreaks in ostriches in the Western Cape province, South Africa. Serum surveys were conducted for veterinarians, farmworkers, and laboratory and abattoir workers involved in 2 AI outbreaks in the Western Cape province: (1) controlling and culling of 42000 ostriches during (HPAI)H5N2 outbreaks in ostriches (2011) (n = 207); (2) movement control during (LPAI)H7N1 outbreaks in 2012 (n = 66). A third serosurvey was conducted on state veterinarians from across the country in 2012 tasked with disease control in general (n = 37). Antibodies to H5 and H7 were measured by means of hemagglutination inhibition and microneutralization assays, with microneutralization assay titers >40 considered positive. Two of 207 (1%) participants were seropositive for H5 and 4 of 207 (2%) for H7 in 2011, compared with 1 of 66 (1.5%) and 8 of 66 (13%) in 2012. Although individuals in all professions tested seropositive, abattoir workers (10 of 97; 10.3%) were significantly more at risk of influenza A(H7N1) infection (P = .001) than those in other professions (2 of 171;1.2%). Among state veterinarians, 4 of 37(11%) were seropositive for H7 and 1 of 37 (2.7%) for H5. Investigations of (LP)H7N1-associated fatalities in wild birds and quarantined exotic birds in Gauteng, AI outbreaks in poultry in KwaZulu-Natal, and ostriches in Western Cape province provide possible exposure events. (LPAI)H7N1 strains pose a greater infection-risk than (HPAI)H5N2 strains to persons involved in control of outbreaks in infected birds, with ostrich abattoir workers at highest risk. © 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.

A review on the clinical spectrum and natural history of human influenza.

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Punpanich, Warunee; Chotpitayasunondh, Tawee

2012-10-01

The objective of this review is to provide updated information on the clinical spectrum and natural history of human influenza, including risk factors for severe disease, and to identify the knowledge gap in this area. We searched the MEDLINE database of the recent literature for the period January 2009 to August 17, 2011 with regard to the abovementioned aspects of human influenza, focusing on A(H1N1)pdm09 and seasonal influenza. The clinical spectrum and outcomes of cases of A(H1N1)pdm09 influenza have been mild and rather indistinguishable from those of seasonal influenza. Sporadic cases covering a wide range of neurological complications have been reported. Underlying predisposing conditions considered to be high-risk for A(H1N1)pdm09 infections are generally similar to those of seasonal influenza, but with two additional risk groups: pregnant women and the morbidly obese. Co-infections with bacteria and D222/N variants or 225G substitution of the viral genome have also been reported to be significant factors associated with the severity of disease. The current knowledge gap includes: (1) a lack of clarification regarding the relatively greater severity of the Mexican A(H1N1)pdm09 influenza outbreak in the early phase of the pandemic; (2) insufficient data on the clinical impact, risk factors, and outcomes of human infections caused by resistant strains of influenza; and (3) insufficient data from less developed countries that would enable them to prioritize strategies for influenza prevention and control. Clinical features and risk factors of A(H1N1)pdm09 are comparable to those of seasonal influenza. Emerging risk factors for severe disease with A(H1N1)pdm09 include morbid obesity, pregnancy, bacterial co-infections, and D222/N variants or 225G substitution of the viral genome. Copyright © 2012 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Massively multiplexed microbial identification using resequencing DNA microarrays for outbreak investigation

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Leski, T. A.; Ansumana, R.; Jimmy, D. H.; Bangura, U.; Malanoski, A. P.; Lin, B.; Stenger, D. A.

2011-06-01

Multiplexed microbial diagnostic assays are a promising method for detection and identification of pathogens causing syndromes characterized by nonspecific symptoms in which traditional differential diagnosis is difficult. Also such assays can play an important role in outbreak investigations and environmental screening for intentional or accidental release of biothreat agents, which requires simultaneous testing for hundreds of potential pathogens. The resequencing pathogen microarray (RPM) is an emerging technological platform, relying on a combination of massively multiplex PCR and high-density DNA microarrays for rapid detection and high-resolution identification of hundreds of infectious agents simultaneously. The RPM diagnostic system was deployed in Sierra Leone, West Africa in collaboration with Njala University and Mercy Hospital Research Laboratory located in Bo. We used the RPM-Flu microarray designed for broad-range detection of human respiratory pathogens, to investigate a suspected outbreak of avian influenza in a number of poultry farms in which significant mortality of chickens was observed. The microarray results were additionally confirmed by influenza specific real-time PCR. The results of the study excluded the possibility that the outbreak was caused by influenza, but implicated Klebsiella pneumoniae as a possible pathogen. The outcome of this feasibility study confirms that application of broad-spectrum detection platforms for outbreak investigation in low-resource locations is possible and allows for rapid discovery of the responsible agents, even in cases when different agents are suspected. This strategy enables quick and cost effective detection of low probability events such as outbreak of a rare disease or intentional release of a biothreat agent.

Viral etiologies of influenza-like illness and severe acute respiratory infections in Thailand.

Science.gov (United States)

Chittaganpitch, Malinee; Waicharoen, Sunthareeya; Yingyong, Thitipong; Praphasiri, Prabda; Sangkitporn, Somchai; Olsen, Sonja J; Lindblade, Kim A

2018-07-01

Information on the burden, characteristics and seasonality of non-influenza respiratory viruses is limited in tropical countries. Describe the epidemiology of selected non-influenza respiratory viruses in Thailand between June 2010 and May 2014 using a sentinel surveillance platform established for influenza. Patients with influenza-like illness (ILI; history of fever or documented temperature ≥38°C, cough, not requiring hospitalization) or severe acute respiratory infection (SARI; history of fever or documented temperature ≥38°C, cough, onset respiratory syncytial virus (RSV), metapneumovirus (MPV), parainfluenza viruses (PIV) 1-3, and adenoviruses by polymerase chain reaction (PCR) or real-time reverse transcriptase-PCR. We screened 15 369 persons with acute respiratory infections and enrolled 8106 cases of ILI (5069 cases respiratory viruses tested, while for SARI cases respiratory viruses, particularly seasonality, although adjustments to case definitions may be required. © 2018 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Ethics for pandemics beyond influenza: Ebola, drug-resistant tuberculosis, and anticipating future ethical challenges in pandemic preparedness and response.

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Smith, Maxwell J; Silva, Diego S

2015-01-01

The unprecedented outbreak of Ebola virus disease (EVD) in West Africa has raised several novel ethical issues for global outbreak preparedness. It has also illustrated that familiar ethical issues in infectious disease management endure despite considerable efforts to understand and mitigate such issues in the wake of past outbreaks. To improve future global outbreak preparedness and response, we must examine these shortcomings and reflect upon the current state of ethical preparedness. To this end, we focus our efforts in this article on the examination of one substantial area: ethical guidance in pandemic plans. We argue that, due in part to their focus on considerations arising specifically in relation to pandemics of influenza origin, pandemic plans and their existing ethical guidance are ill-equipped to anticipate and facilitate the navigation of unique ethical challenges that may arise in other infectious disease pandemics. We proceed by outlining three reasons why this is so, and situate our analysis in the context of the EVD outbreak and the threat posed by drug-resistant tuberculosis: (1) different infectious diseases have distinct characteristics that challenge anticipated or existing modes of pandemic prevention, preparedness, response, and recovery, (2) clear, transparent, context-specific ethical reasoning and justification within current influenza pandemic plans are lacking, and (3) current plans neglect the context of how other significant pandemics may manifest. We conclude the article with several options for reflecting upon and ultimately addressing ethical issues that may emerge with different infectious disease pandemics.

Proinflammatory Cytokine Responses in Extra-Respiratory Tissues During Severe Influenza

NARCIS (Netherlands)

Short, Kirsty R; Veeris, Rebecca; Leijten, Lonneke M; van den Brand, Judith M; Jong, Victor L; Stittelaar, Koert J; Osterhaus, Ab D M E|info:eu-repo/dai/nl/074960172; Andeweg, Arno C; van Riel, Debby

2017-01-01

Severe influenza is often associated with disease manifestations outside the respiratory tract. While proinflammatory cytokines can be detected in the lungs and blood of infected patients, the role of extra-respiratory organs in the production of proinflammatory cytokines is unknown. Here, we show

Proinflammatory Cytokine Responses in Extra-Respiratory Tissues during Severe Influenza

NARCIS (Netherlands)

Short, Kirsty R.; Veeris, Rebecca; Leijten, Lonneke M.; van den Brand, Judith M A; Jong, Victor L.; Stittelaar, Koert; Osterhaus, Ab D.M.E.; Andeweg, Arno C; Van Riel, Debby

2017-01-01

Severe influenza is often associated with disease manifestations outside the respiratory tract. While proinflammatory cytokines can be detected in the lungs and blood of infected patients, the role of extra-respiratory organs in the production of proinflammatory cytokines is unknown. Here, we show

Illness Severity and Work Productivity Loss Among Working Adults With Medically Attended Acute Respiratory Illnesses: US Influenza Vaccine Effectiveness Network 2012-2013.

Science.gov (United States)

Petrie, Joshua G; Cheng, Caroline; Malosh, Ryan E; VanWormer, Jeffrey J; Flannery, Brendan; Zimmerman, Richard K; Gaglani, Manjusha; Jackson, Michael L; King, Jennifer P; Nowalk, Mary Patricia; Benoit, Joyce; Robertson, Anne; Thaker, Swathi N; Monto, Arnold S; Ohmit, Suzanne E

2016-02-15

Influenza causes significant morbidity and mortality, with considerable economic costs, including lost work productivity. Influenza vaccines may reduce the economic burden through primary prevention of influenza and reduction in illness severity. We examined illness severity and work productivity loss among working adults with medically attended acute respiratory illnesses and compared outcomes for subjects with and without laboratory-confirmed influenza and by influenza vaccination status among subjects with influenza during the 2012-2013 influenza season. Illnesses laboratory-confirmed as influenza (ie, cases) were subjectively assessed as more severe than illnesses not caused by influenza (ie, noncases) based on multiple measures, including current health status at study enrollment (≤7 days from illness onset) and current activity and sleep quality status relative to usual. Influenza cases reported missing 45% more work hours (20.5 vs 15.0; P productivity as impeded to a greater degree (6.0 vs 5.4; P productivity loss were noted for vaccinated subjects. Influenza illnesses were more severe and resulted in more missed work hours and productivity loss than illnesses not confirmed as influenza. Modest reductions in illness severity for vaccinated cases were observed. These findings highlight the burden of influenza illnesses and illustrate the importance of laboratory confirmation of influenza outcomes in evaluations of vaccine effectiveness. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Estimated incidence of influenza-associated severe acute respiratory infections in Indonesia, 2013-2016.

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Susilarini, Ni K; Haryanto, Edy; Praptiningsih, Catharina Y; Mangiri, Amalya; Kipuw, Natalie; Tarya, Irmawati; Rusli, Roselinda; Sumardi, Gestafiana; Widuri, Endang; Sembiring, Masri M; Noviyanti, Widya; Widaningrum, Christina; Lafond, Kathryn E; Samaan, Gina; Setiawaty, Vivi

2018-01-01

Indonesia's hospital-based Severe Acute Respiratory Infection (SARI) surveillance system, Surveilans Infeksi Saluran Pernafasan Akut Berat Indonesia (SIBI), was established in 2013. While respiratory illnesses such as SARI pose a significant problem, there are limited incidence-based data on influenza disease burden in Indonesia. This study aimed to estimate the incidence of influenza-associated SARI in Indonesia during 2013-2016 at three existing SIBI surveillance sites. From May 2013 to April 2016, inpatients from sentinel hospitals in three districts of Indonesia (Gunung Kidul, Balikpapan, Deli Serdang) were screened for SARI. Respiratory specimens were collected from eligible inpatients and screened for influenza viruses. Annual incidence rates were calculated using these SIBI-enrolled influenza-positive SARI cases as a numerator, with a denominator catchment population defined through hospital admission survey (HAS) to identify respiratory-coded admissions by age to hospitals in the sentinel site districts. From May 2013 to April 2016, there were 1527 SARI cases enrolled, of whom 1392 (91%) had specimens tested and 199 (14%) were influenza-positive. The overall estimated annual incidence of influenza-associated SARI ranged from 13 to 19 per 100 000 population. Incidence was highest in children aged 0-4 years (82-114 per 100 000 population), followed by children 5-14 years (22-36 per 100 000 population). Incidence rates of influenza-associated SARI in these districts indicate a substantial burden of influenza hospitalizations in young children in Indonesia. Further studies are needed to examine the influenza burden in other potential risk groups such as pregnant women and the elderly. © 2017 The Authors. Influenza and Other Respiratory Viruses. Published by John Wiley & Sons Ltd.

Human Infection with Avian Influenza A(H7N9) Virus - China

Science.gov (United States)

... response operations Diseases Biorisk reduction Disease outbreak news Human infection with avian influenza A(H7N9) virus – China ... Region (SAR) notified WHO of a laboratory-confirmed human infection with avian influenza A(H7N9) virus and ...

Reconstructing the 2003/2004 H3N2 influenza epidemic in Switzerland with a spatially explicit, individual-based model

Science.gov (United States)

2011-01-01

Background Simulation models of influenza spread play an important role for pandemic preparedness. However, as the world has not faced a severe pandemic for decades, except the rather mild H1N1 one in 2009, pandemic influenza models are inherently hypothetical and validation is, thus, difficult. We aim at reconstructing a recent seasonal influenza epidemic that occurred in Switzerland and deem this to be a promising validation strategy for models of influenza spread. Methods We present a spatially explicit, individual-based simulation model of influenza spread. The simulation model bases upon (i) simulated human travel data, (ii) data on human contact patterns and (iii) empirical knowledge on the epidemiology of influenza. For model validation we compare the simulation outcomes with empirical knowledge regarding (i) the shape of the epidemic curve, overall infection rate and reproduction number, (ii) age-dependent infection rates and time of infection, (iii) spatial patterns. Results The simulation model is capable of reproducing the shape of the 2003/2004 H3N2 epidemic curve of Switzerland and generates an overall infection rate (14.9 percent) and reproduction numbers (between 1.2 and 1.3), which are realistic for seasonal influenza epidemics. Age and spatial patterns observed in empirical data are also reflected by the model: Highest infection rates are in children between 5 and 14 and the disease spreads along the main transport axes from west to east. Conclusions We show that finding evidence for the validity of simulation models of influenza spread by challenging them with seasonal influenza outbreak data is possible and promising. Simulation models for pandemic spread gain more credibility if they are able to reproduce seasonal influenza outbreaks. For more robust modelling of seasonal influenza, serological data complementing sentinel information would be beneficial. PMID:21554680

Sequential detection of influenza epidemics by the Kolmogorov-Smirnov test

Directory of Open Access Journals (Sweden)

Closas Pau

2012-10-01

Full Text Available Abstract Background Influenza is a well known and common human respiratory infection, causing significant morbidity and mortality every year. Despite Influenza variability, fast and reliable outbreak detection is required for health resource planning. Clinical health records, as published by the Diagnosticat database in Catalonia, host useful data for probabilistic detection of influenza outbreaks. Methods This paper proposes a statistical method to detect influenza epidemic activity. Non-epidemic incidence rates are modeled against the exponential distribution, and the maximum likelihood estimate for the decaying factor λ is calculated. The sequential detection algorithm updates the parameter as new data becomes available. Binary epidemic detection of weekly incidence rates is assessed by Kolmogorov-Smirnov test on the absolute difference between the empirical and the cumulative density function of the estimated exponential distribution with significance level 0 ≤ α ≤ 1. Results The main advantage with respect to other approaches is the adoption of a statistically meaningful test, which provides an indicator of epidemic activity with an associated probability. The detection algorithm was initiated with parameter λ0 = 3.8617 estimated from the training sequence (corresponding to non-epidemic incidence rates of the 2008-2009 influenza season and sequentially updated. Kolmogorov-Smirnov test detected the following weeks as epidemic for each influenza season: 50−10 (2008-2009 season, 38−50 (2009-2010 season, weeks 50−9 (2010-2011 season and weeks 3 to 12 for the current 2011-2012 season. Conclusions Real medical data was used to assess the validity of the approach, as well as to construct a realistic statistical model of weekly influenza incidence rates in non-epidemic periods. For the tested data, the results confirmed the ability of the algorithm to detect the start and the end of epidemic periods. In general, the proposed test could

Efficacy and efficiency of poultry carcass composting using different mechanical mixing equipment for avian influenza outbreaks

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Jennifer Elizabeth Keaten

2017-05-01

Full Text Available Background and Aim: Avian influenza (AI is a viral disease that caused the largest animal disease outbreak in the history of US agriculture. There are several disposal methods of AI infected poultry carcasses available in the US, which include on-site burial, landfill, incineration, rendering, and composting. Of these methods, composting is the most environmentally friendly and poses a low risk for biosecurity. The United States Department of Agriculture (USDA has developed a comprehensive plan for composting AI infected carcasses. The current protocols have the potential for areas of anaerobic pockets within the windrow due to inadequate mixing and the large carcass size of whole birds. This could lead to ineffective virus neutralization or prolonged composting times and higher resource costs. The purpose of this project was to determine if using a horizontal mixer (HM wagon to mix composting ingredients or a vertical mixer (VM wagon to mix and cut up the compositing ingredients is an economical and timely means to accelerate the tissue break-down and obtain optimal temperatures for poultry carcass composting during an AI outbreak. Materials and Methods: A replicated trial with three treatments, HM, conventional layering (CL and VM, and three replications was initiated at the Compost Research and Education Center part of the University of Maine Forest and Agricultural Experimental Station called High Moor Farm. Daily temperatures and screened core sample weights (screen weights on day 0, 16, and 30 were recorded for each of the compost piles. The time to build each replication was recorded and used to help calculate the cost of each method. Data on equipment, carbon material and labor costs were collected from private contractors from the 2014 to 2016 highly pathogenic AI (HPAI outbreak and used to compare costs between methods. Results: All treatment methods reached USDA protocol temperatures to neutralize the HPAI virus. Screen weights for

Secondary Bacterial Infections Associated with Influenza Pandemics

Science.gov (United States)

Morris, Denise E.; Cleary, David W.; Clarke, Stuart C.

2017-01-01

Lower and upper respiratory infections are the fourth highest cause of global mortality (Lozano et al., 2012). Epidemic and pandemic outbreaks of respiratory infection are a major medical concern, often causing considerable disease and a high death toll, typically over a relatively short period of time. Influenza is a major cause of epidemic and pandemic infection. Bacterial co/secondary infection further increases morbidity and mortality of influenza infection, with Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus reported as the most common causes. With increased antibiotic resistance and vaccine evasion it is important to monitor the epidemiology of pathogens in circulation to inform clinical treatment and development, particularly in the setting of an influenza epidemic/pandemic. PMID:28690590

Secondary Bacterial Infections Associated with Influenza Pandemics

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Denise E. Morris

2017-06-01

Full Text Available Lower and upper respiratory infections are the fourth highest cause of global mortality (Lozano et al., 2012. Epidemic and pandemic outbreaks of respiratory infection are a major medical concern, often causing considerable disease and a high death toll, typically over a relatively short period of time. Influenza is a major cause of epidemic and pandemic infection. Bacterial co/secondary infection further increases morbidity and mortality of influenza infection, with Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus reported as the most common causes. With increased antibiotic resistance and vaccine evasion it is important to monitor the epidemiology of pathogens in circulation to inform clinical treatment and development, particularly in the setting of an influenza epidemic/pandemic.

siRNA for Influenza Therapy

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Sailen Barik

2010-07-01

Full Text Available Influenza virus is one of the most prevalent and ancient infections in humans. About a fifth of world's population is infected by influenza virus annually, leading to high morbidity and mortality, particularly in infants, the elderly and the immunocompromised. In the US alone, influenza outbreaks lead to roughly 30,000 deaths each year. Current vaccines and anti-influenza drugs are of limited use due to high mutation rate of the virus and side effects. In recent years, RNA interference, triggered by synthetic short interfering RNA (siRNA, has rapidly evolved as a potent antiviral regimen. Properly designed siRNAs have been shown to function as potent inhibitors of influenza virus replication. The siRNAs outperform traditional small molecule antivirals in a number of areas, such as ease of design, modest cost, and fast turnaround. Although specificity and tissue delivery remain major bottlenecks in the clinical applications of RNAi in general, intranasal application of siRNA against respiratory viruses including, but not limited to influenza virus, has experienced significant success and optimism, which is reviewed here.

siRNA for Influenza Therapy.

Science.gov (United States)

Barik, Sailen

2010-07-01

Influenza virus is one of the most prevalent and ancient infections in humans. About a fifth of world's population is infected by influenza virus annually, leading to high morbidity and mortality, particularly in infants, the elderly and the immunocompromised. In the US alone, influenza outbreaks lead to roughly 30,000 deaths each year. Current vaccines and anti-influenza drugs are of limited use due to high mutation rate of the virus and side effects. In recent years, RNA interference, triggered by synthetic short interfering RNA (siRNA), has rapidly evolved as a potent antiviral regimen. Properly designed siRNAs have been shown to function as potent inhibitors of influenza virus replication. The siRNAs outperform traditional small molecule antivirals in a number of areas, such as ease of design, modest cost, and fast turnaround. Although specificity and tissue delivery remain major bottlenecks in the clinical applications of RNAi in general, intranasal application of siRNA against respiratory viruses including, but not limited to influenza virus, has experienced significant success and optimism, which is reviewed here.

Characterisation and Identification of Avian Influenza Virus (AI

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Dyah Ayu Hewajuli

2008-06-01

Full Text Available Avian Influenza is caused by Influenza A virus which is a member of Orthomyxoviridae family. Influenza A virus is enveloped single stranded RNA with eight-segmented, negative polarity and filament or oval form, 50 – 120 by 200 – 300 nm diameters. Influenza A viruses have been found to infect birds, human, pig, horse and sometimes in the other mammalian such as seal and whale. The viruses are divided into different subtypes based on the antigenic protein which covers the virus surface i.e. Haemaglutinin (HA and Neuraminidase (NA. In addition, the nomenclature of subtype virus is based on HA and NA i.e HxNx, for example H5N1, H9N2 and the others. According to pathogenic, it could be divided into two distinct groups, they are Highly Pathogenic Avian Influenza (HPAI and Low Pathogenic Avian Influenza (LPAI. The Avian Influenza viruses have been continuously occurred and spread out in some continents such us America, Europe, Africa and Asian countries. The outbreak of Avian Influenza caused high mortality on birds and it has been reported that in human case Avian Influenza subtype H5N1 virus has caused several deaths. To anticipate this condition, an effort to prevent the transmission of Avian Influenza is needed. These strategic attempts include biosecurity, depopulation, vaccination, control of virus movement, monitoring and evaluation. Laboratory diagnostic plays an important role for successful prevention, control and eradication programs of Avian Influenza. Recently, there are two diagnostic methods for Avian Influenza. They are conventional (virological diagnosis and molecular methods. The conventional method is usually used for initial diagnostic of Avian Influenza. The conventional method takes more time and more costly, whereas the molecular method is more effective than conventional method. Based on the available diagnostic technique, basically diagnostic of Avian Influenza is done by serology test, isolation and identification as well

Global Dynamics of Avian Influenza Epidemic Models with Psychological Effect

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Sanhong Liu

2015-01-01

Full Text Available Cross-sectional surveys conducted in Thailand and China after the outbreaks of the avian influenza A H5N1 and H7N9 viruses show a high degree of awareness of human avian influenza in both urban and rural populations, a higher level of proper hygienic practice among urban residents, and in particular a dramatically reduced number of visits to live markets in urban population after the influenza A H7N9 outbreak in China in 2013. In this paper, taking into account the psychological effect toward avian influenza in the human population, a bird-to-human transmission model in which the avian population exhibits saturation effect is constructed. The dynamical behavior of the model is studied by using the basic reproduction number. The results demonstrate that the saturation effect within avian population and the psychological effect in human population cannot change the stability of equilibria but can affect the number of infected humans if the disease is prevalent. Numerical simulations are given to support the theoretical results and sensitivity analyses of the basic reproduction number in terms of model parameters that are performed to seek for effective control measures for avian influenza.

Global dynamics of avian influenza epidemic models with psychological effect.

Science.gov (United States)

Liu, Sanhong; Pang, Liuyong; Ruan, Shigui; Zhang, Xinan

2015-01-01

Cross-sectional surveys conducted in Thailand and China after the outbreaks of the avian influenza A H5N1 and H7N9 viruses show a high degree of awareness of human avian influenza in both urban and rural populations, a higher level of proper hygienic practice among urban residents, and in particular a dramatically reduced number of visits to live markets in urban population after the influenza A H7N9 outbreak in China in 2013. In this paper, taking into account the psychological effect toward avian influenza in the human population, a bird-to-human transmission model in which the avian population exhibits saturation effect is constructed. The dynamical behavior of the model is studied by using the basic reproduction number. The results demonstrate that the saturation effect within avian population and the psychological effect in human population cannot change the stability of equilibria but can affect the number of infected humans if the disease is prevalent. Numerical simulations are given to support the theoretical results and sensitivity analyses of the basic reproduction number in terms of model parameters that are performed to seek for effective control measures for avian influenza.

Fire Severity Controlled Susceptibility to a 1940s Spruce Beetle Outbreak in Colorado, USA.

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Dominik Kulakowski

Full Text Available The frequency, magnitude, and size of forest disturbances are increasing globally. Much recent research has focused on how the occurrence of one disturbance may affect susceptibility to subsequent disturbances. While much has been learned about such linked disturbances, the strength of the interactions is likely to be contingent on the severity of disturbances as well as climatic conditions, both of which can affect disturbance intensity and tree resistance to disturbances. Subalpine forests in western Colorado were affected by extensive and severe wildfires in the late 19th century and an extensive and severe outbreak of spruce beetle (Dendroctonus rufipennis in the 1940s. Previous research found that most, but not all, of the stands that burned and established following the late 19th century fires were not susceptible to the 1940s outbreak as beetles preferentially attack larger trees and stands in advanced stages of development. However, previous research also left open the possibility that some stands that burned and established following the 19th century fires may have been attacked during the 1940s outbreak. Understanding how strongly stand structure, as shaped by disturbances of varying severity, affected susceptibility to past outbreaks is important to provide a baseline for assessing the degree to which recent climate change may be relaxing the preferences of beetles for larger trees and for stands in latter stages of structural development and thereby changing the nature of linked disturbances. Here, dendroecological methods were used to study disturbance history and tree age of stands in the White River National Forest in Western Colorado that were identified in historical documents or remotely-sensed images as having burned in the 19th century and having been attacked by spruce beetle in the 1940s. Dendroecological reconstructions indicate that in young post-fire stands only old remnant trees that survived the otherwise stand

Exploring contacts facilitating transmission of influenza A(H5N1) virus between poultry farms in West Java, Indonesia

NARCIS (Netherlands)

Wibawa, Hendra; Karo-Karo, Desniwaty; Pribadi, Eko Sugeng; Bouma, Annemarie; Bodewes, Rogier; Vernooij, Hans; Diyantoro,; Sugama, Agus; Muljono, David H.; Koch, Guus; Tjatur Rasa, Fadjar Sumping; Stegeman, Arjan

2018-01-01

Highly pathogenic avian influenza virus (HPAIV) H5N1 has been reported in Asia, including Indonesia since 2003. Although several risk factors related to the HPAIV outbreaks in poultry in Indonesia have been identified, little is known of the contact structure of farms of different poultry production

The long term impact of the 1918 influenza pandemic in Norway

OpenAIRE

Bakken, Magnus Røthe; Husøy, Sigrid Johanne

2016-01-01

Advisor: Aline Bütikofer A growing literature show the negative effect of prenatal health shocks on childhood and adult outcomes. Several studies exploit disease outbreaks to find causal effects of in utero exposure on various outcomes. We build on the existing literature by applying theories of in utero health effects to Norwegian data. This thesis uses the 1918 Spanish Influenza pandemic as a natural experiment to investigate the impact of prenatal health shock on various ...

Intravenous Immunoglobulin Protects Against Severe Pandemic Influenza Infection

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Steven Rockman

2017-05-01

Full Text Available Influenza is a highly contagious, acute, febrile respiratory infection that can have fatal consequences particularly in individuals with chronic illnesses. Sporadic reports suggest that intravenous immunoglobulin (IVIg may be efficacious in the influenza setting. We investigated the potential of human IVIg to ameliorate influenza infection in ferrets exposed to either the pandemic H1N1/09 virus (pH1N1 or highly pathogenic avian influenza (H5N1. IVIg administered at the time of influenza virus exposure led to a significant reduction in lung viral load following pH1N1 challenge. In the lethal H5N1 model, the majority of animals given IVIg survived challenge in a dose dependent manner. Protection was also afforded by purified F(ab′2 but not Fc fragments derived from IVIg, supporting a specific antibody-mediated mechanism of protection. We conclude that pre-pandemic IVIg can modulate serious influenza infection-associated mortality and morbidity. IVIg could be useful prophylactically in the event of a pandemic to protect vulnerable population groups and in the critical care setting as a first stage intervention.

Fire Severity Controlled Susceptibility to a 1940s Spruce Beetle Outbreak in Colorado, USA.

Science.gov (United States)

Kulakowski, Dominik; Veblen, Thomas T; Bebi, Peter

2016-01-01

The frequency, magnitude, and size of forest disturbances are increasing globally. Much recent research has focused on how the occurrence of one disturbance may affect susceptibility to subsequent disturbances. While much has been learned about such linked disturbances, the strength of the interactions is likely to be contingent on the severity of disturbances as well as climatic conditions, both of which can affect disturbance intensity and tree resistance to disturbances. Subalpine forests in western Colorado were affected by extensive and severe wildfires in the late 19th century and an extensive and severe outbreak of spruce beetle (Dendroctonus rufipennis) in the 1940s. Previous research found that most, but not all, of the stands that burned and established following the late 19th century fires were not susceptible to the 1940s outbreak as beetles preferentially attack larger trees and stands in advanced stages of development. However, previous research also left open the possibility that some stands that burned and established following the 19th century fires may have been attacked during the 1940s outbreak. Understanding how strongly stand structure, as shaped by disturbances of varying severity, affected susceptibility to past outbreaks is important to provide a baseline for assessing the degree to which recent climate change may be relaxing the preferences of beetles for larger trees and for stands in latter stages of structural development and thereby changing the nature of linked disturbances. Here, dendroecological methods were used to study disturbance history and tree age of stands in the White River National Forest in Western Colorado that were identified in historical documents or remotely-sensed images as having burned in the 19th century and having been attacked by spruce beetle in the 1940s. Dendroecological reconstructions indicate that in young post-fire stands only old remnant trees that survived the otherwise stand-replacing fires were

Equine influenza in Brazil

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Patricia Filippsen Favaro

2016-06-01

Full Text Available Equine influenza virus (EIV (H3N8 and H7N7 is the causative agent of equine influenza, or equine flu. The H7N7 subtype has been considered to be extinct worldwide since 1980. Affected animals have respiratory symptoms that can be worsened by secondary bacterial respiratory infection, thereby leading to great economic losses in the horse-breeding industry. In Brazil, equine influenza outbreaks were first reported in 1963 and studies on hemagglutination antibodies against viral subtypes in Brazilian horses have been conducted since then. The objective of the present review was to present the history of the emergence of EIV around the world and in Brazil and the studies that have thus far been developed on EIV in Brazilian equines.

No Major Host Genetic Risk Factor Contributed to A(H1N12009 Influenza Severity.

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Koldo Garcia-Etxebarria

Full Text Available While most patients affected by the influenza A(H1N1 pandemic experienced mild symptoms, a small fraction required hospitalization, often without concomitant factors that could explain such a severe course. We hypothesize that host genetic factors could contribute to aggravate the disease. To test this hypothesis, we compared the allele frequencies of 547,296 genome-wide single nucleotide polymorphisms (SNPs between 49 severe and 107 mild confirmed influenza A cases, as well as against a general population sample of 549 individuals. When comparing severe vs. mild influenza A cases, only one SNP was close to the conventional p = 5×10-8. This SNP, rs28454025, sits in an intron of the GSK233 gene, which is involved in a neural development, but seems not to have any connections with immunological or inflammatory functions. Indirectly, a previous association reported with CD55 was replicated. Although sample sizes are low, we show that the statistical power in our design was sufficient to detect highly-penetrant, quasi-Mendelian genetic factors. Hence, and assuming that rs28454025 is likely to be a false positive, no major genetic factor was detected that could explain poor influenza A course.

MANAGEMENT PATIENT OF SWINE INFLUENZA

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Endra Gunawan

2015-05-01

Full Text Available Influenza is an acute respiratory diseases caused by various influenza virus which infect the upper and lower respiratory tract and often accompanied by systemic symptoms such as fever, headache and muscle pain. Influenza spreads through the air. Swine influenza comes from swine and can cause an outbreaks in pig flocks. Even this is a kind of a rare case but the swine influenza could be transmitted to human by direct contact with infected swine or through environment that already being contaminated by swine influenza virus. There are 3 types of swine influenza virus namely H1N1, H3N2 and H1N2. Type H1N1 swine-virus had been known since 1918. Avian influenza virus infection is transmitted from one person to another through secret containing virus. Virus is binded into the mucous cells of respiratory tract before it is finally infecting the cells itself. Management patients with H1N1 influenza is based on the complications and the risk. Besides, it is also need to consider the clinical criteria of the patient. Therapy medicamentosa is applied to the patients by giving an antiviral, antibiotics and symptomatic therapy. Prevention can be done by avoid contact with infected animal or environment, having antiviral prophylaxis and vaccination.

Influenza Virus A (H1N1) in Giant Anteaters (Myrmecophaga tridactyla)

OpenAIRE

Nofs, Sally; Abd-Eldaim, Mohamed; Thomas, Kathy V.; Toplon, David; Rouse, Dawn; Kennedy, Melissa

2009-01-01

In February 2007, an outbreak of respiratory disease occurred in a group of giant anteaters (Myrmecophaga tridactyla) at the Nashville Zoo. Isolates from 2 affected animals were identified in March 2007 as a type A influenza virus related to human influenza subtype H1N1.

Influenza virus A (H1N1) in giant anteaters (Myrmecophaga tridactyla).

Science.gov (United States)

Nofs, Sally; Abd-Eldaim, Mohamed; Thomas, Kathy V; Toplon, David; Rouse, Dawn; Kennedy, Melissa

2009-07-01

In February 2007, an outbreak of respiratory disease occurred in a group of giant anteaters (Myrmecophaga tridactyla) at the Nashville Zoo. Isolates from 2 affected animals were identified in March 2007 as a type A influenza virus related to human influenza subtype H1N1.

Pandemic vaccination strategies and influenza severe outcomes during the influenza A(H1N1)pdm09 pandemic and the post-pandemic influenza season

DEFF Research Database (Denmark)

Gil Cuesta, Julita; Aavitsland, Preben; Englund, Hélène

2016-01-01

During the 2009/10 influenza A(H1N1)pdm09 pandemic, the five Nordic countries adopted different approaches to pandemic vaccination. We compared pandemic vaccination strategies and severe influenza outcomes, in seasons 2009/10 and 2010/11 in these countries with similar influenza surveillance...... systems. We calculated the cumulative pandemic vaccination coverage in 2009/10 and cumulative incidence rates of laboratory confirmed A(H1N1)pdm09 infections, intensive care unit (ICU) admissions and deaths in 2009/10 and 2010/11. We estimated incidence risk ratios (IRR) in a Poisson regression model...... with the other countries. In 2010/11 Denmark had a significantly higher cumulative incidence of A(H1N1)pdm09 ICU admissions (IRR: 2.4; 95% confidence interval (CI): 1.9-3.0) and deaths (IRR: 8.3; 95% CI: 5.1-13.5). Compared with Denmark, the other countries had higher pandemic vaccination coverage...

Changing human mobility and the spreading rate of global influenza outbreaks

NARCIS (Netherlands)

Slaa, Jan Willem

2010-01-01

Influenza, commonly called the flu, is an infectious disease which causes up to 500,000 deaths annually during seasonal epidemics. Influenza viruses circulate in many different types and in many species, such as birds, swines and humans. When a new human

Migration of whooper swans and outbreaks of highly pathogenic avian influenza H5N1 virus in eastern Asia.

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Scott H Newman

Full Text Available Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1 requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp. has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer and in habitats (areas of natural vegetation where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks at or near their breeding grounds.

Quantification of bird-to-bird and bird-to-human infections during 2013 novel H7N9 avian influenza outbreak in China.

Science.gov (United States)

Hsieh, Ying-Hen; Wu, Jianhong; Fang, Jian; Yang, Yong; Lou, Jie

2014-01-01

From February to May, 2013, 132 human avian influenza H7N9 cases were identified in China resulting in 37 deaths. We developed a novel, simple and effective compartmental modeling framework for transmissions among (wild and domestic) birds as well as from birds to human, to infer important epidemiological quantifiers, such as basic reproduction number for bird epidemic, bird-to-human infection rate and turning points of the epidemics, for the epidemic via human H7N9 case onset data and to acquire useful information regarding the bird-to-human transmission dynamics. Estimated basic reproduction number for infections among birds is 4.10 and the mean daily number of human infections per infected bird is 3.16*10-5 [3.08*10-5, 3.23*10-5]. The turning point of 2013 H7N9 epidemic is pinpointed at April 16 for bird infections and at April 9 for bird-to-human transmissions. Our result reveals very low level of bird-to-human infections, thus indicating minimal risk of widespread bird-to-human infections of H7N9 virus during the outbreak. Moreover, the turning point of the human epidemic, pinpointed at shortly after the implementation of full-scale control and intervention measures initiated in early April, further highlights the impact of timely actions on ending the outbreak. This is the first study where both the bird and human components of an avian influenza epidemic can be quantified using only the human case data.

The long term impact of the 1918 influenza pandemic in Norway

OpenAIRE

Bakken, Magnus Røthe; Husøy, Sigrid Johanne

2016-01-01

A growing literature show the negative effect of prenatal health shocks on childhood and adult outcomes. Several studies exploit disease outbreaks to find causal effects of in utero exposure on various outcomes. We build on the existing literature by applying theories of in utero health effects to Norwegian data. This thesis uses the 1918 Spanish Influenza pandemic as a natural experiment to investigate the impact of prenatal health shock on various long term outcomes in Norway...

A review of influenza detection and prediction through social networking sites.

Science.gov (United States)

Alessa, Ali; Faezipour, Miad

2018-02-01

Early prediction of seasonal epidemics such as influenza may reduce their impact in daily lives. Nowadays, the web can be used for surveillance of diseases. Search engines and social networking sites can be used to track trends of different diseases seven to ten days faster than government agencies such as Center of Disease Control and Prevention (CDC). CDC uses the Illness-Like Influenza Surveillance Network (ILINet), which is a program used to monitor Influenza-Like Illness (ILI) sent by thousands of health care providers in order to detect influenza outbreaks. It is a reliable tool, however, it is slow and expensive. For that reason, many studies aim to develop methods that do real time analysis to track ILI using social networking sites. Social media data such as Twitter can be used to predict the spread of flu in the population and can help in getting early warnings. Today, social networking sites (SNS) are used widely by many people to share thoughts and even health status. Therefore, SNS provides an efficient resource for disease surveillance and a good way to communicate to prevent disease outbreaks. The goal of this study is to review existing alternative solutions that track flu outbreak in real time using social networking sites and web blogs. Many studies have shown that social networking sites can be used to conduct real time analysis for better predictions.

Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

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Bin Zhou

2014-10-01

Full Text Available Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV. Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1. This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2 showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

Science.gov (United States)

Zhou, Bin; Ma, Jingjiao; Liu, Qinfang; Bawa, Bhupinder; Wang, Wei; Shabman, Reed S; Duff, Michael; Lee, Jinhwa; Lang, Yuekun; Cao, Nan; Nagy, Abdou; Lin, Xudong; Stockwell, Timothy B; Richt, Juergen A; Wentworth, David E; Ma, Wenjun

2014-10-01

Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

Trends of influenza B during the 2010-2016 seasons in 2 regions of north and south Italy: The impact of the vaccine mismatch on influenza immunisation strategy.

Science.gov (United States)

Orsi, Andrea; Colomba, Giuseppina Maria Elena; Pojero, Fanny; Calamusa, Giuseppe; Alicino, Cristiano; Trucchi, Cecilia; Canepa, Paola; Ansaldi, Filippo; Vitale, Francesco; Tramuto, Fabio

2018-03-04

Influenza A and B viruses are responsible for respiratory infections, representing globally seasonal threats to human health. The 2 viral types often co-circulate and influenza B plays an important role in the spread of infection. A 6-year retrospective surveillance study was conducted between 2010 and 2016 in 2 large administrative regions of Italy, located in the north (Liguria) and in the south (Sicily) of the country, to describe the burden and epidemiology of both B/Victoria and B/Yamagata lineages in different healthcare settings. Influenza B viruses were detected in 5 of 6 seasonal outbreaks, exceeding influenza A during the season 2012-2013. Most of influenza B infections were found in children aged ≤ 14 y and significant differences were observed in the age-groups infected by the different lineages. B/Victoria strains prevailed in younger population than B/Yamagata, but also were more frequently found in the community setting. Conversely, B/Yamagata viruses were prevalent among hospitalized cases suggesting their potential role in the development of more severe disease. The relative proportions of viral lineages varied from year to year, resulting in different lineage-level mismatch for the B component of trivalent influenza vaccine. Our findings confirmed the need for continuous virological surveillance of seasonal epidemics and bring attention to the adoption of universal influenza immunization program in the childhood. The use of tetravalent vaccine formulations may be useful to improve the prevention and control of the influenza burden in general population.

Prevalence of avian influenza virus in wild birds before and after the HPAI H5N8 outbreak in 2014 in South Korea.

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Shin, Jeong-Hwa; Woo, Chanjin; Wang, Seung-Jun; Jeong, Jipseol; An, In-Jung; Hwang, Jong-Kyung; Jo, Seong-Deok; Yu, Seung Do; Choi, Kyunghee; Chung, Hyen-Mi; Suh, Jae-Hwa; Kim, Seol-Hee

2015-07-01

Since 2003, highly pathogenic avian influenza (HPAI) virus outbreaks have occurred five times in Korea, with four HPAI H5N1 outbreaks and one HPAI H5N8 outbreak. Migratory birds have been suggested to be the first source of HPAI in Korea. Here, we surveyed migratory wild birds for the presence of AI and compared regional AI prevalence in wild birds from September 2012 to April 2014 for birds having migratory pathways in South Korea. Finally, we investigated the prevalence of AI in migratory birds before and after HPAI H5N8 outbreaks. Overall, we captured 1617 migratory wild birds, while 18,817 feces samples and 74 dead birds were collected from major wild bird habitats. A total of 21 HPAI viruses were isolated from dead birds, and 86 low pathogenic AI (LPAI) viruses were isolated from captured birds and from feces samples. Spatiotemporal distribution analysis revealed that AI viruses were spread southward until December, but tended to shift north after January, consistent with the movement of migratory birds in South Korea. Furthermore, we found that LPAI virus prevalences within wild birds were notably higher in 2013-2014 than the previous prevalence during the northward migration season. The data from our study demonstrate the importance of the surveillance of AI in wild birds. Future studies including in-depth genetic analysis in combination with evaluation of the movement and ecology of migratory birds might help us to bridge the gaps in our knowledge and better explain, predict, and ultimately prevent future HPAI outbreaks.

Pandemic Influenza A (N1H1: what to learn from it?

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Cristina Rolim Neumann

2009-09-01

Full Text Available Influenza pandemics are natural events that occur periodically. The pandemic’s current agent, Influenza virus A (H1N1 was first identified in Mexico in April 2009, spread rapidly and has caused deaths mainly among young adults. The objective of this manuscript is to present the biological aspects involved in the outbreak of this pandemic, as well as population-control strategies for pandemic influenza. In addition to the population mitigation measures, whose efficacy has been described by theoretical models, today we also have drugs with efficacy valued in some patient groups. These drugs reduce moderately the duration and severity of symptoms, as long as they are started early. This pandemic, with a large number of cases, but caused by a virus of low lethality, could be managed preferably in Units of Primary Health Care, that would treat the wild cases and forward the severe ones to the hospitals. However, what occurred in numerous cities was the burden on emergency care with triage situations, forcing managers to improvise field hospitals, tents and containers to house the extra work in services that were already at the limit of physical infrastructure and human resources. Pandemic Influenza exposed the fragility of our network of primary care and lack of ICU beds.

Avian Influenza A(H5N1) Virus Outbreak Investigation: Application of the FAO-OIE-WHO Four-way Linking Framework in Indonesia.

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Setiawaty, V; Dharmayanti, N L P I; Misriyah; Pawestri, H A; Azhar, M; Tallis, G; Schoonman, L; Samaan, G

2015-08-01

WHO, FAO and OIE developed a 'four-way linking' framework to enhance the cross-sectoral sharing of epidemiological and virological information in responding to zoonotic disease outbreaks. In Indonesia, outbreak response challenges include completeness of data shared between human and animal health authorities. The four-way linking framework (human health laboratory/epidemiology and animal health laboratory/epidemiology) was applied in the investigation of the 193 rd human case of avian influenza A(H5N1) virus infection. As recommended by the framework, outbreak investigation and risk assessment findings were shared. On 18 June 2013, a hospital in West Java Province reported a suspect H5N1 case in a 2-year-old male. The case was laboratory-confirmed that evening, and the information was immediately shared with the Ministry of Agriculture. The human health epidemiology/laboratory team investigated the outbreak and conducted an initial risk assessment on 19 June. The likelihood of secondary cases was deemed low as none of the case contacts were sick. By 3 July, no secondary cases associated with the outbreak were identified. The animal health epidemiology/laboratory investigation was conducted on 19-25 June and found that a live bird market visited by the case was positive for H5N1 virus. Once both human and market virus isolates were sequenced, a second risk assessment was conducted jointly by the human health and animal health epidemiology/laboratory teams. This assessment concluded that the likelihood of additional human cases associated with this outbreak was low but that future sporadic human infections could not be ruled out because of challenges in controlling H5N1 virus contamination in markets. Findings from the outbreak investigation and risk assessments were shared with stakeholders at both Ministries. The four-way linking framework clarified the type of data to be shared. Both human health and animal health teams made ample data available, and there was

[Analysis on diagnosis and treatment of 15 cases with severe influenza A].

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Zuo, Yunlong; Yang, Yiyu; Hong, Jie; Wu, Zhiyuan; Yu, Li; Tao, Jianping; Gong, Sitang

2014-02-01

To analyze the diagnosis and treatment characteristics of patients with severe Influenza A. A retrospective investigation on the clinical manifestation, chest radiography, electronic fiber bronchoscopy and the histology of the cast, rescue course and outcome was conducted in 15 children with severe influenza A during January to May of 2013. Eleven cases were male, the range of age was 2 to 6 years; 5 cases were female, the range of age was 1 month to 6 years, accouting for 4.2% of hospitalized children with influenza. Three patients had an underlying chronic disease, two had nephrotic syndrome, and one had congenital heart disease. All the 15 cases were diagnosed as severe influenza A virus infection complicated with pneumonia and respiratory failure, of whom 10 cases were infected with H1N1 virus , the other 5 cases could not be identified as H1N1 virus by using H1N1 kit, but none of the 15 cases were infected with H7N9 virus. Of 15 cases, 8 had atelectasis, 4 had pneumothorax, 3 had pneumomediastinum, 4 had pleural effusion, 1 had pneumorrhagia; 12 patients required mechanical ventilation. 1 only required noninvasive mask CPAP, 2 did not require assisted ventilation, they were just given mask oxygen. Seven cases' sputum culture showed combined infection with bacteria and fungi, sputum smear examination detected: G(+) cocci in 2 cases, and G(-) bacilli in the other 2. By using electronic fiber bronchoscopy, bronchial cast was detected in 5 patiens. Histological examination of the bronchial cast revealed a fibrinous exudation containing large quantity of eosinophils, neutrophils in 1 patients, fibrinous exudation and necrotic material containing large quantity of neutrophils in 4 patients. After the bronchial casts were removed, 4 patients were improved greatly. All patients were treated with postural drainage of left and right side position, massage of electric oscillation, strengthening the sputum suction aiming to improve pulmonary ventilation function. Three

Influenza hospitalization epidemiology from a severe acute respiratory infection surveillance system in Jordan, January 2008-February 2014.

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Al-Abdallat, Mohammad; Dawson, Patrick; Haddadin, Aktham Jeries; El-Shoubary, Waleed; Dueger, Erica; Al-Sanouri, Tarek; Said, Mayar M; Talaat, Maha

2016-03-01

Acute respiratory infections (ARIs) are a major cause of morbidity and mortality worldwide. Influenza typically contributes substantially to the burden of ARI, but only limited data are available on influenza activity and seasonality in Jordan. Syndromic case definitions were used to identify individuals with severe acute respiratory infections (SARI) admitted to four sentinel hospitals in Jordan. Demographic and clinical data were collected. Nasopharyngeal and oropharyngeal swabs were tested for influenza using real-time reverse transcription polymerase chain reaction and typed as influenza A or B, with influenza A further subtyped. From January 2008-February 2014, 2891 SARI cases were tested for influenza, and 257 (9%) were positive. While 73% of all SARI cases were under 5 years of age, only 57% of influenza-positive cases were under 5 years of age. Eight (3%) influenza-positive cases died. An annual seasonal pattern of influenza activity was observed. The proportion of influenza-positive cases peaked during November-January (14-42%) in the non-pandemic years. Influenza is associated with substantial morbidity and mortality in Jordan. The seasonal pattern of influenza aligns with known Northern Hemisphere seasonality. Further characterization of the clinical and financial burden of influenza in Jordan will be critical in supporting decisions regarding disease control activities. © 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Severe mortality impact of the 1957 influenza pandemic in Chile

DEFF Research Database (Denmark)

Chowell, Gerardo; Simonsen, Lone; Fuentes, Rodrigo

2017-01-01

INTRODUCTION: Epidemiological studies of the 1957 influenza pandemic are scarce, particularly from lower income settings. METHODS: We analyzed the spatial-temporal mortality patterns of the 1957 influenza pandemic in Chile including detailed age-specific mortality data from a large city...... with high baseline mortality (R2=41.8%; P=0.02), but not with latitude (P>0.7). Excess mortality rates increased sharply with age. Transmissibility declined from R=1.4-2.1 to R=1.2-1.4 between the two pandemic waves. CONCLUSIONS: The estimated A/H2N2 mortality burden in Chile is the highest on record...... for this pandemic - about 3-5 times as severe as that experienced in wealthier nations. The global impact of this pandemic may be substantially underestimated from previous studies based on high-income countries....

Outbreak of influenza type A (H1N1 in Iporanga, São Paulo State, Brazil Epidemia de influenza A (H1N1 no Município de Iporanga, SP, Brasil

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Terezinha Maria de PAIVA

2001-12-01

Full Text Available From June to July 1999 an outbreak of acute respiratory illness occurred in the town of Iporanga. Out of a total of 4,837 inhabitants, 324 cases were notified to the Regional Surveillance Service. Influenza virus was isolated from 57.1% of the collected samples and 100% seroconversion to influenza A (H1N1 was obtained in 20 paired sera tested. The isolates were related to the A/Bayern/07/95 strain (H1N1. The percentages of cases notified during the outbreak were 28.4%, 29.0%, 20.7%, 6.2% and 15.7% in the age groups of 0-4, 5-9, 10-14, 15-19 and older than 20 years, respectively. The highest proportion of positives was observed among children younger than 14 years and no cases were notified in people older than 65 years, none of whom had been recently vaccinated against influenza. These findings suggest a significant vaccine protection against A/Bayern/7/95, the H1 component included in the 1997-98 influenza vaccine for elderly people. This viral strain is antigenically and genetically related to A/Beijing/262/95, the H1 component of the 1999 vaccine. Vaccines containing A/Beijing/262/95 (H1N1 stimulated post-immunization hemagglutination inhibition antibodies equivalent in frequency and titre to both A/Beijing/262/95-like and A/Bayern/7/95-like viruses. Thus, this investigation demonstrates the effectiveness of vaccination against influenza virus in the elderly.Durante os meses de junho e julho de 1999, foram notificados 324 casos de doença respiratória aguda no Município de Iporanga-SP. O isolamento do vírus da influenza do tipo A/Bayern/07/95 (H1N1 e a conversão sorológica para a estirpe viral (H1N1 foram de 57,1% e 100%, respectivamente. A porcentagem de casos com diagnóstico clínico notificados durante a epidemia foi de 28,4%, 29,0%, 20,7%, 6,2% e 15,7%, nas faixas etárias de 0-4, 5-9, 10-14, 15-19 anos e indivíduos acima de 20 anos de idade, respectivamente. Observou-se maior incidência da doença entre os indivíduos menores de

Characteristics of patients with influenza-like illness, severe acture respiratory illness, and laboratory-confirmed influenza at a major children's hospital in Angola, 2009-2011.

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Cardoso, Yolanda; Oliveira, Erika; Vasconcelos, Jocelyne; Cohen, Adam L; Francisco, Moises

2012-12-15

There are no published data on influenza trends in Angola, where pneumonia is a leading cause of death among young children. This study aims to describe the seasonal trends, types, and subtypes of influenza virus recovered from patients with respiratory illness who were admitted to the major children's hospital in Angola from May 2009 through April 2011. Nasal and oral swabs were collected from patients seen in the outpatient clinic with influenza-like illness (ILI) or hospitalized with severe acute respiratory illness (SARI) and tested for influenza virus by polymerase chain reaction assays. Of 691 samples collected, 334 (48%) were from case patients with ILI, and 357 (52%) were from case patients with SARI. Most (86%) of these children were Angola.

Economic impacts of avian influenza outbreaks in Kerala, India.

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Govindaraj, G; Sridevi, R; Nandakumar, S N; Vineet, R; Rajeev, P; Binu, M K; Balamurugan, V; Rahman, H

2018-04-01

This study assessed the short-run impact to poultry farmers, duck hatcheries, control costs, compensation paid to stakeholders (transfer payments) and market reactions on own and substitute product prices and backwater tourism (boat operators) due to avian influenza (AI) outbreaks in Kuttanad region of Kerala, India, during 2014. The primary data from 91 poultry farms (duck farms, broiler chicken and backyard poultry), four hatcheries and 90 backwater boat owners were collected through pre-tested schedules. The secondary data on transfer payments and expenditure incurred to control AI were collected from developmental departments and were analysed. The estimated loss (culling live birds, eggs and feed destruction) per duck farm was USD 9,181, USD 3,889 and USD 156 in case of commercial farms reared for meat, dual-purpose and backyard farms, respectively. The loss incurred by small-scale broiler and backyard poultry farms was USD 453 and USD 40, respectively. The loss incurred by large and small duck hatcheries was USD 11,963 and USD 5,790, respectively, due to culling of hatchlings, young birds and destroying eggs. The government invested USD 744,890 to contain the disease spread through massive culling, surveillance and monitoring of poultry and humans due to zoonotic nature of the disease. A sharp market reaction on own and substitute product prices and eight weeks' time lag in price recovery was observed. The consequential impact on tourism especially for the backwater boat operators amounted to a loss of USD 2,280/boat due to fall in tourist inflow. Since, control measures are post-incidence, it is necessary to adopt appropriate preventive bio-security measures at the farm level besides periodical screening of domestic birds in migratory birds' flyway locations like Kuttanad to reduce the AI burden on various stakeholders including government. © 2017 Blackwell Verlag GmbH.

Universal Influenza Vaccines, a Dream to Be Realized Soon

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Han Zhang

2014-04-01

Full Text Available Due to frequent viral antigenic change, current influenza vaccines need to be re-formulated annually to match the circulating strains for battling seasonal influenza epidemics. These vaccines are also ineffective in preventing occasional outbreaks of new influenza pandemic viruses. All these challenges call for the development of universal influenza vaccines capable of conferring broad cross-protection against multiple subtypes of influenza A viruses. Facilitated by the advancement in modern molecular biology, delicate antigen design becomes one of the most effective factors for fulfilling such goals. Conserved epitopes residing in virus surface proteins including influenza matrix protein 2 and the stalk domain of the hemagglutinin draw general interest for improved antigen design. The present review summarizes the recent progress in such endeavors and also covers the encouraging progress in integrated antigen/adjuvant delivery and controlled release technology that facilitate the development of an affordable universal influenza vaccine.

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity.

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Tippett, Michael K; Cohen, Joel E

2016-02-29

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from 'outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954-2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related.

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity

Science.gov (United States)

Tippett, Michael K.; Cohen, Joel E.

2016-01-01

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from ‘outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954–2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related. PMID:26923210

No Major Host Genetic Risk Factor Contributed to A(H1N1)2009 Influenza Severity.

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Garcia-Etxebarria, Koldo; Bracho, María Alma; Galán, Juan Carlos; Pumarola, Tomàs; Castilla, Jesús; Ortiz de Lejarazu, Raúl; Rodríguez-Dominguez, Mario; Quintela, Inés; Bonet, Núria; Garcia-Garcerà, Marc; Domínguez, Angela; González-Candelas, Fernando; Calafell, Francesc

2015-01-01

While most patients affected by the influenza A(H1N1) pandemic experienced mild symptoms, a small fraction required hospitalization, often without concomitant factors that could explain such a severe course. We hypothesize that host genetic factors could contribute to aggravate the disease. To test this hypothesis, we compared the allele frequencies of 547,296 genome-wide single nucleotide polymorphisms (SNPs) between 49 severe and 107 mild confirmed influenza A cases, as well as against a general population sample of 549 individuals. When comparing severe vs. mild influenza A cases, only one SNP was close to the conventional p = 5×10-8. This SNP, rs28454025, sits in an intron of the GSK233 gene, which is involved in a neural development, but seems not to have any connections with immunological or inflammatory functions. Indirectly, a previous association reported with CD55 was replicated. Although sample sizes are low, we show that the statistical power in our design was sufficient to detect highly-penetrant, quasi-Mendelian genetic factors. Hence, and assuming that rs28454025 is likely to be a false positive, no major genetic factor was detected that could explain poor influenza A course.

Deep sequencing of H7N8 avian influenza viruses from surveillance zone supports H7N8 high pathogenicity avian influenza was limited to a single outbreak farm in Indiana during 2016.

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Lee, Dong-Hun; Torchetti, Mia Kim; Killian, Mary Lea; Swayne, David E

2017-07-01

In mid-January 2016, an outbreak of H7N8 high-pathogenicity avian influenza virus (HPAIV) in commercial turkeys occurred in Indiana. Surveillance within the 10km control zone identified H7N8 low-pathogenicity avian influenza virus (LPAIV) in nine surrounding turkey flocks but no other HPAIV-affected premises. We sequenced four of the H7N8 HPAIV isolated from the single farm and nine LPAIV identified during control zone surveillance. Evaluation included phylogenetic network analysis indicating close relatedness across the HPAIV and LPAIV, and that the progenitor H7N8 LPAIV spread among the affected turkey farms in Indiana, followed by spontaneous mutation to HPAIV on a single premise through acquisition of three basic amino acids at the hemagglutinin cleavage site. Deep sequencing of the available viruses failed to identify subpopulations in either the HPAIV or LPAIV suggesting mutation to HPAIV likely occurred on a single farm and the HPAIV did not spread to epidemiologically linked LPAIV-affected farms. Published by Elsevier Inc.

Mortality, severe acute respiratory infection, and influenza-like illness associated with influenza A(H1N1pdm09 in Argentina, 2009.

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Eduardo Azziz-Baumgartner

Full Text Available INTRODUCTION: While there is much information about the burden of influenza A(H1N1pdm09 in North America, little data exist on its burden in South America. METHODS: During April to December 2009, we actively searched for persons with severe acute respiratory infection and influenza-like illness (ILI in three sentinel cities. A proportion of case-patients provided swabs for influenza testing. We estimated the number of case-patients that would have tested positive for influenza by multiplying the number of untested case-patients by the proportion who tested positive. We estimated rates by dividing the estimated number of case-patients by the census population after adjusting for the proportion of case-patients with missing illness onset information and ILI case-patients who visited physicians multiple times for one illness event. RESULTS: We estimated that the influenza A(H1N1pdm09 mortality rate per 100,000 person-years (py ranged from 1.5 among persons aged 5-44 years to 5.6 among persons aged ≥ 65 years. A(H1N1pdm09 hospitalization rates per 100,000 py ranged between 26.9 among children aged <5 years to 41.8 among persons aged ≥ 65 years. Influenza A(H1N1pdm09 ILI rates per 100 py ranged between 1.6 among children aged <5 to 17.1 among persons aged 45-64 years. While 9 (53% of 17 influenza A(H1N1pdm09 decedents with available data had obesity and 7 (17% of 40 had diabetes, less than 4% of surviving influenza A(H1N1pdm09 case-patients had these pre-existing conditions (p ≤ 0.001. CONCLUSION: Influenza A(H1N1pdm09 caused a similar burden of disease in Argentina as in other countries. Such disease burden suggests the potential value of timely influenza vaccinations.

Identification of equine influenza virus infection in Asian wild horses (Equus przewalskii).

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Yin, Xin; Lu, Gang; Guo, Wei; Qi, Ting; Ma, Jian; Zhu, Chao; Zhao, Shihua; Pan, Jialiang; Xiang, Wenhua

2014-05-01

An outbreak of equine influenza was observed in the Asian wild horse population in Xinjiang Province, China, in 2007. Nasal swabs were collected from wild horses and inoculated into 9-10-day SPF embryonated eggs. The complete genome of the isolate was sequenced. A comparison of the amino acid sequence revealed that the isolate was an equine influenza virus strain, which we named A/equine/Xinjiang/4/2007. Each gene of the virus was found to have greater than 99 % homology to equine influenza virus strains of the Florida-2 sublineage, which were circulating simultaneously in China, and a lesser amount of homology was found to the strain A/equine/Qinghai/1/1994 (European lineage), which was isolated during the last outbreak in China. These observations were confirmed by phylogenetic analysis. In addition, the deduced amino acid sequence of the neuraminidase of the A/equine/Xinjiang/4/2007 strain was identical to that of A/equine/California/8560/2002, an American isolate, and was found to be similar to those of Florida-2 strains found in other countries by comparing them with nine other field strains that were isolated in China from 2007 to 2008. It is suggested that the neuraminidase segment of A/equine/Xinjiang/4/2007 may have been obtained from equine influenza virus strains from other countries. We report for the first time an outbreak of equine influenza in the Asian wild horse population, and the complete genome of the virus is provided and analyzed.

Analysis of the PDZ binding specificities of Influenza A Virus NS1 proteins

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Nagasaka Kazunori

2011-01-01

Full Text Available Abstract The Influenza A virus non-structural protein 1 (NS1 is a multifunctional virulence factor with several protein-protein interaction domains, involved in preventing apoptosis of the infected cell and in evading the interferon response. In addition, the majority of influenza A virus NS1 proteins have a class I PDZ-binding motif at the C-terminus, and this itself has been shown to be a virulence determinant. In the majority of human influenza NS1 proteins the consensus motif is RSxV: in avian NS1 it is ESxV. Of the few human strains that have the avian motif, all were from very high mortality outbreaks of the disease. Previous work has shown that minor differences in PDZ-binding motifs can have major effects on the spectrum of cellular proteins targeted. In this study we analyse the effect of these differences upon the binding of Influenza A virus NS1 protein to a range of cellular proteins involved in polarity and signal transduction.

The public health impact of avian influenza viruses.

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Katz, J M; Veguilla, V; Belser, J A; Maines, T R; Van Hoeven, N; Pappas, C; Hancock, K; Tumpey, T M

2009-04-01

Influenza viruses with novel hemagglutinin and 1 or more accompanying genes derived from avian influenza viruses sporadically emerge in humans and have the potential to result in a pandemic if the virus causes disease and spreads efficiently in a population that lacks immunity to the novel hemagglutinin. Since 1997, multiple avian influenza virus subtypes have been transmitted directly from domestic poultry to humans and have caused a spectrum of human disease, from asymptomatic to severe and fatal. To assess the pandemic risk that avian influenza viruses pose, we have used multiple strategies to better understand the capacity of avian viruses to infect, cause disease, and transmit among mammals, including humans. Seroepidemiologic studies that evaluate the frequency and risk of human infection with avian influenza viruses in populations with exposure to domestic or wild birds can provide a better understanding of the pandemic potential of avian influenza subtypes. Investigations conducted in Hong Kong following the first H5N1 outbreak in humans in 1997 determined that exposure to poultry in live bird markets was a key risk factor for human disease. Among poultry workers, butchering and exposure to sick poultry were risk factors for antibody to H5 virus, which provided evidence for infection. A second risk assessment tool, the ferret, can be used to evaluate the level of virulence and potential for host-to-host transmission of avian influenza viruses in this naturally susceptible host. Avian viruses isolated from humans exhibit a level of virulence and transmissibility in ferrets that generally reflects that seen in humans. The ferret model thus provides a means to monitor emerging avian influenza viruses for pandemic risk, as well as to evaluate laboratory-generated reassortants and mutants to better understand the molecular basis of influenza virus transmissibility. Taken together, such studies provide valuable information with which we can assess the public

Distinct Host Tropism Protein Signatures to Identify Possible Zoonotic Influenza A Viruses.

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Eng, Christine L P; Tong, Joo Chuan; Tan, Tin Wee

2016-01-01

Zoonotic influenza A viruses constantly pose a health threat to humans as novel strains occasionally emerge from the avian population to cause human infections. Many past epidemic as well as pandemic strains have originated from avian species. While most viruses are restricted to their primary hosts, zoonotic strains can sometimes arise from mutations or reassortment, leading them to acquire the capability to escape host species barrier and successfully infect a new host. Phylogenetic analyses and genetic markers are useful in tracing the origins of zoonotic infections, but there are still no effective means to identify high risk strains prior to an outbreak. Here we show that distinct host tropism protein signatures can be used to identify possible zoonotic strains in avian species which have the potential to cause human infections. We have discovered that influenza A viruses can now be classified into avian, human, or zoonotic strains based on their host tropism protein signatures. Analysis of all influenza A viruses with complete proteome using the host tropism prediction system, based on machine learning classifications of avian and human viral proteins has uncovered distinct signatures of zoonotic strains as mosaics of avian and human viral proteins. This is in contrast with typical avian or human strains where they show mostly avian or human viral proteins in their signatures respectively. Moreover, we have found that zoonotic strains from the same influenza outbreaks carry similar host tropism protein signatures characteristic of a common ancestry. Our results demonstrate that the distinct host tropism protein signature in zoonotic strains may prove useful in influenza surveillance to rapidly identify potential high risk strains circulating in avian species, which may grant us the foresight in anticipating an impending influenza outbreak.

Challenges and Strategies of Laboratory Diagnosis for Newly Emerging Influenza Viruses in Taiwan: A Decade after SARS

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Jih-Hui Lin

2015-01-01

Full Text Available Since the first case of severe acute respiratory syndrome (SARS in Taiwan was identified in March 2003, viral respiratory infections, in particular the influenza virus, have become a national public health concern. Taiwan would face a serious threat of public health problems if another SARS epidemic overlapped with a flu outbreak. After SARS, the Taiwan Centers for Disease Control accelerated and strengthened domestic research on influenza and expanded the exchange of information with international counterparts. The capacity of influenza A to cross species barriers presents a potential threat to human health. Given the mutations of avian flu viruses such as H7N9, H6N1, and H10N8, all countries, including Taiwan, must equip themselves to face a possible epidemic or pandemic. Such preparedness requires global collaboration.

Enhancing Seasonal Influenza Surveillance: Topic Analysis of Widely Used Medicinal Drugs Using Twitter Data.

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Kagashe, Ireneus; Yan, Zhijun; Suheryani, Imran

2017-09-12

Uptake of medicinal drugs (preventive or treatment) is among the approaches used to control disease outbreaks, and therefore, it is of vital importance to be aware of the counts or frequencies of most commonly used drugs and trending topics about these drugs from consumers for successful implementation of control measures. Traditional survey methods would have accomplished this study, but they are too costly in terms of resources needed, and they are subject to social desirability bias for topics discovery. Hence, there is a need to use alternative efficient means such as Twitter data and machine learning (ML) techniques. Using Twitter data, the aim of the study was to (1) provide a methodological extension for efficiently extracting widely consumed drugs during seasonal influenza and (2) extract topics from the tweets of these drugs and to infer how the insights provided by these topics can enhance seasonal influenza surveillance. From tweets collected during the 2012-13 flu season, we first identified tweets with mentions of drugs and then constructed an ML classifier using dependency words as features. The classifier was used to extract tweets that evidenced consumption of drugs, out of which we identified the mostly consumed drugs. Finally, we extracted trending topics from each of these widely used drugs' tweets using latent Dirichlet allocation (LDA). Our proposed classifier obtained an F 1 score of 0.82, which significantly outperformed the two benchmark classifiers (ie, Pstrategies for mitigating the severity of seasonal influenza outbreaks. The proposed methods can be extended to the outbreaks of other diseases. ©Ireneus Kagashe, Zhijun Yan, Imran Suheryani. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 12.09.2017.

A Simulation-Based Evaluation of Premovement Active Surveillance Protocol Options for the Managed Movement of Turkeys to Slaughter During an Outbreak of Highly Pathogenic Avian Influenza in the United States.

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Todd Weaver, J; Malladi, Sasidhar; Bonney, Peter J; Patyk, Kelly A; Bergeron, Justin G; Middleton, Jamie L; Alexander, Catherine Y; Goldsmith, Timothy J; Halvorson, David A

2016-05-01

Risk management decisions associated with live poultry movement during a highly pathogenic avian influenza (HPAI) outbreak should be carefully considered. Live turkey movements may pose a risk for disease spread. On the other hand, interruptions in scheduled movements can disrupt business continuity. The Secure Turkey Supply (STS) Plan was developed through an industry-government-academic collaboration to address business continuity concerns that might arise during a HPAI outbreak. STS stakeholders proposed outbreak response measure options that were evaluated through risk assessment. The developed approach relies on 1) diagnostic testing of two pooled samples of swabs taken from dead turkeys immediately before movement via the influenza A matrix gene real-time reverse transcriptase polymerase chain reaction (rRT-PCR) test; 2) enhanced biosecurity measures in combination with a premovement isolation period (PMIP), restricting movement onto the premises for a few days before movement to slaughter; and 3) incorporation of a distance factor from known infected flocks such that exposure via local area spread is unlikely. Daily exposure likelihood estimates from spatial kernels from past HPAI outbreaks were coupled with simulation models of disease spread and active surveillance to evaluate active surveillance protocol options that differ with respect to the number of swabs per pooled sample and the timing of the tests in relation to movement. Simulation model results indicate that active surveillance testing, in combination with strict biosecurity, substantially increased HPAI virus detection probability. When distance from a known infected flock was considered, the overall combined likelihood of moving an infected, undetected turkey flock to slaughter was predicted to be lower at 3 and 5 km. The analysis of different active surveillance protocol options is designed to incorporate flexibility into HPAI emergency response plans.

The role of rodents in avian influenza outbreaks in poultry farms: a review.

Science.gov (United States)

Velkers, Francisca C; Blokhuis, Simon J; Veldhuis Kroeze, Edwin J B; Burt, Sara A

2017-12-01

Wild migratory birds are associated with global avian influenza virus (AIV) spread. Although direct contact with wild birds and contaminated fomites is unlikely in modern non-free range poultry farms applying biosecurity measures, AIV outbreaks still occur. This suggests involvement of other intermediate factors for virus transmission between wild birds and poultry. This review describes current evidence of the potential role of rodents in AIV transmission from wild birds to poultry and between poultry houses. Rodents can be abundant around poultry houses, share their habitat with waterfowl and can readily enter poultry houses. Survival of AIV from waterfowl in poultry house surroundings and on the coat of rodents suggests that rodents are likely to act as mechanical vector. AIVs can replicate in rodents without adaptation, resulting in high viral titres in lungs and nasal turbinates, virus presence in nasal washes and saliva, and transmission to naïve contact animals. Therefore, active AIV shedding by infected rodents may play a role in transmission to poultry. Further field and experimental studies are needed to provide evidence for a role of rodents in AIV epidemiology. Making poultry houses rodent-proof and the immediate surroundings unattractive for rodents are recommended as preventive measures against possible AIV introduction.

Mitigating Infectious Disease Outbreaks

Science.gov (United States)

Davey, Victoria

The emergence of new, transmissible infections poses a significant threat to human populations. As the 2009 novel influenza A/H1N1 pandemic and the 2014-2015 Ebola epidemic demonstrate, we have observed the effects of rapid spread of illness in non-immune populations and experienced disturbing uncertainty about future potential for human suffering and societal disruption. Clinical and epidemiologic characteristics of a newly emerged infectious organism are usually gathered in retrospect as the outbreak evolves and affects populations. Knowledge of potential effects of outbreaks and epidemics and most importantly, mitigation at community, regional, national and global levels is needed to inform policy that will prepare and protect people. Study of possible outcomes of evolving epidemics and application of mitigation strategies is not possible in observational or experimental research designs, but computational modeling allows conduct of `virtual' experiments. Results of well-designed computer simulations can aid in the selection and implementation of strategies that limit illness and death, and maintain systems of healthcare and other critical resources that are vital to public protection. Mitigating Infectious Disease Outbreaks.

A new sentinel surveillance system for severe influenza in England shows a shift in age distribution of hospitalised cases in the post-pandemic period.

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Shelly Bolotin

Full Text Available BACKGROUND: The World Health Organization and European Centre for Disease Prevention and Control have highlighted the importance of establishing systems to monitor severe influenza. Following the H1N1 (2009 influenza pandemic, a sentinel network of 23 Trusts, the UK Severe Influenza Surveillance System (USISS, was established to monitor hospitalisations due to confirmed seasonal influenza in England. This article presents the results of the first season of operation of USISS in 2010/11. METHODOLOGY/PRINCIPAL FINDINGS: A case was defined as a person hospitalised with confirmed influenza of any type. Weekly aggregate numbers of hospitalised influenza cases, broken down by flu type and level of care, were submitted by participating Trusts. Cases in 2010/11 were compared to cases during the 2009 pandemic in hospitals with available surveillance data for both time periods (n = 19. An unexpected resurgence in seasonal A/H1N1 (2009 influenza activity in England was observed in December 2010 with reports of severe disease. Reported cases over the period of 4 October 2010 to 13 February 2011 were mostly due to influenza A/H1N1 (2009. One thousand and seventy-one cases of influenza A/H1N1 (2009 occurred over this period compared to 409 at the same Trusts over the 2009/10 pandemic period (1 April 2009 to 6 January 2010. Median age of influenza A/H1N1 (2009 cases in 2010/11 was 35 years, compared with 20 years during the pandemic (p = <0.0001. CONCLUSIONS/SIGNIFICANCE: The Health Protection Agency successfully established a sentinel surveillance system for severe influenza in 2010/11, detecting a rise in influenza cases mirroring other surveillance indicators. The data indicate an upward shift in the age-distribution of influenza A/H1N1 (2009 during the 2010/11 influenza season as compared to the 2009/10 pandemic. Systems to enable the ongoing surveillance of severe influenza will be a key component in understanding and responding to the evolving

Probable Tiger-to-Tiger Transmission of Avian Influenza H5N1

Science.gov (United States)

Thanawongnuwech, Roongroje; Amonsin, Alongkorn; Tantilertcharoen, Rachod; Damrongwatanapokin, Sudarat; Theamboonlers, Apiradee; Payungporn, Sunchai; Nanthapornphiphat, Kamonchart; Ratanamungklanon, Somchuan; Tunak, Eakchai; Songserm, Thaweesak; Vivatthanavanich, Veravit; Lekdumrongsak, Thawat; Kesdangsakonwut, Sawang; Tunhikorn, Schwann

2005-01-01

During the second outbreak of avian influenza H5N1 in Thailand, probable horizontal transmission among tigers was demonstrated in the tiger zoo. Sequencing and phylogenetic analysis of those viruses showed no differences from the first isolate obtained in January 2004. This finding has implications for influenza virus epidemiology and pathogenicity in mammals. PMID:15890122

Maternal and fetal recovery after severe respiratory failure due to influenza: a case report

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Madsen Kristine

2013-02-01

Full Text Available Abstract Background During pregnancy women are at increased risk of severe complications to influenza infection, including death of mother or fetus, especially if chronic comorbid medical conditions such as diabetes mellitus are present. Case presentation A 36 years old Caucasian pregnant woman with type 1 diabetes underwent mechanical ventilation in gestation week 27 for severe respiratory failure due to influenza and pneumonia. For three weeks during and following her most severe illness, fetal growth could not be detected and the umbilical flows and amniotic fluid volumes were affected too. The possibility of preterm delivery and extracorporeal membrane oxygenation (ECMO treatment were considered, however the patient and her fetus recovered gradually on conservative treatment. Under close surveillance the pregnancy continued until term, with delivery of an infant with appropriate weight for gestational age. Conclusion Preterm delivery and decreased birth weight were reported for women with antepartum pneumonia. Mechanical ventilation and ECMO treatment for severe respiratory failure in pregnancy are life threatening conditions and have been associated with preterm delivery. It remains uncertain if delivery improves the respiratory status of a critically ill woman, and the fetal condition is likely to improve, if the maternal condition is stabilized. Severe respiratory insufficiency requiring mechanical ventilation in a diabetic pregnant woman with influenza was successfully treated conservatively. Despite clear signs of impaired fetal condition in the acute phase, watchful waiting resulted in delivery of a normal weight infant at term.

On avian influenza epidemic models with time delay.

Science.gov (United States)

Liu, Sanhong; Ruan, Shigui; Zhang, Xinan

2015-12-01

After the outbreak of the first avian influenza A virus (H5N1) in Hong Kong in 1997, another avian influenza A virus (H7N9) crossed the species barrier in mainland China in 2013 and 2014 and caused more than 400 human cases with a death rate of nearly 40%. In this paper, we take account of the incubation periods of avian influenza A virus and construct a bird-to-human transmission model with different time delays in the avian and human populations combining the survival probability of the infective avian and human populations at the latent time. By analyzing the dynamical behavior of the model, we obtain a threshold value for the prevalence of avian influenza and investigate local and global asymptotical stability of equilibria of the system.

Developing Universal Influenza Vaccines: Hitting the Nail, Not Just on the Head

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Lidewij C. M. Wiersma

2015-03-01

Full Text Available Influenza viruses have a huge impact on public health. Current influenza vaccines need to be updated annually and protect poorly against antigenic drift variants or novel emerging subtypes. Vaccination against influenza can be improved in two important ways, either by inducing more broadly protective immune responses or by decreasing the time of vaccine production, which is relevant especially during a pandemic outbreak. In this review, we outline the current efforts to develop so-called “universal influenza vaccines”, describing antigens that may induce broadly protective immunity and novel vaccine production platforms that facilitate timely availability of vaccines.

Implementing hospital-based surveillance for severe acute respiratory infections caused by influenza and other respiratory pathogens in New Zealand

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Q Sue Huang

2014-05-01

Full Text Available Background: Recent experience with pandemic influenza A(H1N1pdm09 highlighted the importance of global surveillance for severe respiratory disease to support pandemic preparedness and seasonal influenza control. Improved surveillance in the southern hemisphere is needed to provide critical data on influenza epidemiology, disease burden, circulating strains and effectiveness of influenza prevention and control measures. Hospital-based surveillance for severe acute respiratory infection (SARI cases was established in New Zealand on 30 April 2012. The aims were to measure incidence, prevalence, risk factors, clinical spectrum and outcomes for SARI and associated influenza and other respiratory pathogen cases as well as to understand influenza contribution to patients not meeting SARI case definition. Methods/Design: All inpatients with suspected respiratory infections who were admitted overnight to the study hospitals were screened daily. If a patient met the World Health Organization’s SARI case definition, a respiratory specimen was tested for influenza and other respiratory pathogens. A case report form captured demographics, history of presenting illness, co-morbidities, disease course and outcome and risk factors. These data were supplemented from electronic clinical records and other linked data sources. Discussion: Hospital-based SARI surveillance has been implemented and is fully functioning in New Zealand. Active, prospective, continuous, hospital-based SARI surveillance is useful in supporting pandemic preparedness for emerging influenza A(H7N9 virus infections and seasonal influenza prevention and control.

Evaluating the role of wild songbirds or rodents in spreading avian influenza virus across an agricultural landscape

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Derek D. Houston

2017-12-01

Full Text Available Background Avian influenza virus (AIV infections occur naturally in wild bird populations and can cross the wildlife-domestic animal interface, often with devastating impacts on commercial poultry. Migratory waterfowl and shorebirds are natural AIV reservoirs and can carry the virus along migratory pathways, often without exhibiting clinical signs. However, these species rarely inhabit poultry farms, so transmission into domestic birds likely occurs through other means. In many cases, human activities are thought to spread the virus into domestic populations. Consequently, biosecurity measures have been implemented to limit human-facilitated outbreaks. The 2015 avian influenza outbreak in the United States, which occurred among poultry operations with strict biosecurity controls, suggests that alternative routes of virus infiltration may exist, including bridge hosts: wild animals that transfer virus from areas of high waterfowl and shorebird densities. Methods Here, we examined small, wild birds (songbirds, woodpeckers, etc. and mammals in Iowa, one of the regions hit hardest by the 2015 avian influenza epizootic, to determine whether these animals carry AIV. To assess whether influenza A virus was present in other species in Iowa during our sampling period, we also present results from surveillance of waterfowl by the Iowa Department of Natural Resources and Unites Stated Department of Agriculture. Results Capturing animals at wetlands and near poultry facilities, we swabbed 449 individuals, internally and externally, for the presence of influenza A virus and no samples tested positive by qPCR. Similarly, serology from 402 animals showed no antibodies against influenza A. Although several species were captured at both wetland and poultry sites, the overall community structure of wild species differed significantly between these types of sites. In contrast, 83 out of 527 sampled waterfowl tested positive for influenza A via qPCR. Discussion

Evaluating the role of wild songbirds or rodents in spreading avian influenza virus across an agricultural landscape.

Science.gov (United States)

Houston, Derek D; Azeem, Shahan; Lundy, Coady W; Sato, Yuko; Guo, Baoqing; Blanchong, Julie A; Gauger, Phillip C; Marks, David R; Yoon, Kyoung-Jin; Adelman, James S

2017-01-01

Avian influenza virus (AIV) infections occur naturally in wild bird populations and can cross the wildlife-domestic animal interface, often with devastating impacts on commercial poultry. Migratory waterfowl and shorebirds are natural AIV reservoirs and can carry the virus along migratory pathways, often without exhibiting clinical signs. However, these species rarely inhabit poultry farms, so transmission into domestic birds likely occurs through other means. In many cases, human activities are thought to spread the virus into domestic populations. Consequently, biosecurity measures have been implemented to limit human-facilitated outbreaks. The 2015 avian influenza outbreak in the United States, which occurred among poultry operations with strict biosecurity controls, suggests that alternative routes of virus infiltration may exist, including bridge hosts: wild animals that transfer virus from areas of high waterfowl and shorebird densities. Here, we examined small, wild birds (songbirds, woodpeckers, etc.) and mammals in Iowa, one of the regions hit hardest by the 2015 avian influenza epizootic, to determine whether these animals carry AIV. To assess whether influenza A virus was present in other species in Iowa during our sampling period, we also present results from surveillance of waterfowl by the Iowa Department of Natural Resources and Unites Stated Department of Agriculture. Capturing animals at wetlands and near poultry facilities, we swabbed 449 individuals, internally and externally, for the presence of influenza A virus and no samples tested positive by qPCR. Similarly, serology from 402 animals showed no antibodies against influenza A. Although several species were captured at both wetland and poultry sites, the overall community structure of wild species differed significantly between these types of sites. In contrast, 83 out of 527 sampled waterfowl tested positive for influenza A via qPCR. These results suggest that even though influenza A viruses

An overview of the recent outbreaks of the avian-origin influenza A (H7N9 virus in the human

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Ren-Bin Tang

2013-05-01

Full Text Available Since the first human infection with influenza A (H7N9 viruses have been identified in Shanghai on March 31, 2013, the latest variant of the avian flu virus has spread across four Chinese provinces recently. Human infections with avian influenza are rare and this is the first time that human infection with a low pathogenic avian influenza A virus has been associated with fatal outcome. To date (May 5th, 2013, China had reported 128 confirmed H7N9 infections in human, among 27 died. Most reported cases have severe respiratory illness resulting in severe pneumonia and in some cases have died. No evidence of sustained human-to -humans at this time, however, there is one family cluster with two confirmed cases for which human-to-human transmission cannot be ruled out. Recent evidence showed that the gene sequences of this novel H7N9 virus is primarily zoonotic and may be better adapted than other avian influenza viruses to infect human. Effective global infection control is urgently needed, and further surveillance and analyses should be undertaken to identify the source and mode of transmission of these viruses.

A metagenomic analysis of pandemic influenza A (2009 H1N1 infection in patients from North America.

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Alexander L Greninger

2010-10-01

Full Text Available Although metagenomics has been previously employed for pathogen discovery, its cost and complexity have prevented its use as a practical front-line diagnostic for unknown infectious diseases. Here we demonstrate the utility of two metagenomics-based strategies, a pan-viral microarray (Virochip and deep sequencing, for the identification and characterization of 2009 pandemic H1N1 influenza A virus. Using nasopharyngeal swabs collected during the earliest stages of the pandemic in Mexico, Canada, and the United States (n = 17, the Virochip was able to detect a novel virus most closely related to swine influenza viruses without a priori information. Deep sequencing yielded reads corresponding to 2009 H1N1 influenza in each sample (percentage of aligned sequences corresponding to 2009 H1N1 ranging from 0.0011% to 10.9%, with up to 97% coverage of the influenza genome in one sample. Detection of 2009 H1N1 by deep sequencing was possible even at titers near the limits of detection for specific RT-PCR, and the percentage of sequence reads was linearly correlated with virus titer. Deep sequencing also provided insights into the upper respiratory microbiota and host gene expression in response to 2009 H1N1 infection. An unbiased analysis combining sequence data from all 17 outbreak samples revealed that 90% of the 2009 H1N1 genome could be assembled de novo without the use of any reference sequence, including assembly of several near full-length genomic segments. These results indicate that a streamlined metagenomics detection strategy can potentially replace the multiple conventional diagnostic tests required to investigate an outbreak of a novel pathogen, and provide a blueprint for comprehensive diagnosis of unexplained acute illnesses or outbreaks in clinical and public health settings.

Quantification of the effect of vaccination on transmission of avian influenza (H7N7) in chickens

NARCIS (Netherlands)

Goot, van der A.J.; Koch, G.; Jong, de M.C.M.; Boven, van R.M.

2005-01-01

Recent outbreaks of highly pathogenic avian influenza (HPAI) viruses in poultry and their threatening zoonotic consequences emphasize the need for effective control measures. Although vaccination of poultry against avian influenza provides a potentially attractive control measure, little is known

Clinical characteristics and factors associated with severe acute respiratory infection and influenza among children in Jingzhou, China.

Science.gov (United States)

Huai, Yang; Guan, Xuhua; Liu, Shali; Uyeki, Timothy M; Jiang, Hui; Klena, John; Huang, Jigui; Chen, Maoyi; Peng, Youxing; Yang, Hui; Luo, Jun; Zheng, Jiandong; Peng, Zhibin; Huo, Xixiang; Xiao, Lin; Chen, Hui; Zhang, Yuzhi; Xing, Xuesen; Feng, Luzhao; Hu, Dale J; Yu, Hongjie; Zhan, Faxian; Varma, Jay K

2017-03-01

Influenza is an important cause of respiratory illness in children, but data are limited on hospitalized children with laboratory-confirmed influenza in China. We conducted active surveillance for severe acute respiratory infection (SARI; fever and at least one sign or symptom of acute respiratory illness) among hospitalized pediatric patients in Jingzhou, Hubei Province, from April 2010 to April 2012. Data were collected from enrolled SARI patients on demographics, underlying health conditions, clinical course of illness, and outcomes. Nasal swabs were collected and tested for influenza viruses by reverse transcription polymerase chain reaction. We described the clinical and epidemiological characteristics of children with influenza and analyzed the association between potential risk factors and SARI patients with influenza. During the study period, 15 354 children aged acute respiratory infection patients aged 5-15 years with confirmed influenza (H3N2) infection were more likely than children without influenza to have radiographic diagnosis of pneumonia (11/31, 36% vs 15/105, 14%. Pacute respiratory infection cases aged 5-15 years diagnosed with influenza were also more likely to have a household member who smoked cigarettes compared with SARI cases without a smoking household member (54/208, 26% vs 158/960, 16%, Pinfection was an important contributor to pneumonia requiring hospitalization. Our results highlight the importance of surveillance in identifying factors for influenza hospitalization, monitoring adherence to influenza prevention and treatment strategies, and evaluating the disease burden among hospitalized pediatric SARI patients. Influenza vaccination promotion should target children. © 2016 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Cytokine response patterns in severe pandemic 2009 H1N1 and seasonal influenza among hospitalized adults.

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Nelson Lee

Full Text Available BACKGROUND: Studying cytokine/chemokine responses in severe influenza infections caused by different virus subtypes may improve understanding on pathogenesis. METHODS: Adults hospitalized for laboratory-confirmed seasonal and pandemic 2009 A/H1N1 (pH1N1 influenza were studied. Plasma concentrations of 13 cytokines/chemokines were measured at presentation and then serially, using cytometric-bead-array with flow-cytometry and ELISA. PBMCs from influenza patients were studied for cytokine/chemokine expression using ex-vivo culture (Whole Blood Assay,±PHA/LPS stimulation. Clinical variables were prospectively recorded and analyzed. RESULTS: 63 pH1N1 and 53 seasonal influenza patients were studied. pH1N1 patients were younger (mean±S.D. 42.8±19.2 vs 70.5±16.7 years, and fewer had comorbidities. Respiratory/cardiovascular complications were common in both groups (71.4% vs 81.1%, although severe pneumonia with hypoxemia (54.0% vs 28.3% and ICU admissions (25.4% vs 1.9% were more frequent with pH1N1. Hyperactivation of the proinflammatory cytokines IL-6, CXCL8/IL-8, CCL2/MCP-1 and sTNFR-1 was found in pH1N1 pneumonia (2-15 times normal and in complicated seasonal influenza, but not in milder pH1N1 infections. The adaptive-immunity (Th1/Th17-related CXCL10/IP-10, CXCL9/MIG and IL-17A however, were markedly suppressed in severe pH1N1 pneumonia (2-27 times lower than seasonal influenza; P-values<0.01. This pattern was further confirmed with serial measurements. Hypercytokinemia tended to be sustained in pH1N1 pneumonia, associated with a slower viral clearance [PCR-negativity: day 3-4, 55% vs 85%; day 6-7, 67% vs 100%]. Elevated proinflammatory cytokines, particularly IL-6, predicted ICU admission (adjusted OR 12.6, 95%CI 2.6-61.5, per log(10unit increase; P = 0.002, and correlated with fever, tachypnoea, deoxygenation, and length-of-stay (Spearman's rho, P-values<0.01 in influenza infections. PBMCs in seasonal influenza patients were activated and

Investigating an outbreak of acute fever in Chuuk, Federated States of Micronesia

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Damian Hoy

2014-11-01

Full Text Available Objective: In September 2012, there was an unexpected increase of acute febrile illness (AFI in Chuuk State of the Federated States of Micronesia. At the same time, dengue outbreaks were occurring in two of the Federated States of Micronesia’s other three states. The cause of AFI was suspected to be dengue; however, by the end of October, only one of 39 samples was positive for dengue. The objective of the investigation was to establish the cause of the outbreak. Methods: A line list was created and data analysed by time, place, person and clinical features. Reported symptoms were compared with the published symptoms of several diagnoses and laboratory testing undertaken. Results: Of the 168 suspected cases, 62% were less than 20 years of age and 60% were male. The clinical features of the cases were not typical for dengue but suggestive of respiratory illness. Nasopharyngeal swabs were subsequently collected and found to be positive for influenza. Public health measures were undertaken and the AFI returned to expected levels. Discussion: Clinical diagnosis of acute febrile illness (AFI can often be difficult and misleading. This can mean that opportunities for preventive measures early on in an outbreak are missed. In any outbreak, descriptive epidemiological analyses are valuable in helping to ascertain the cause of the outbreak.

A long-lasting outbreak of Salmonella Typhimurium U323 associated with several pork products, Denmark, 2010

DEFF Research Database (Denmark)

Kuhn, K. G.; Sørensen, Gitte; Torpdahl, M.

2013-01-01

This paper shows that control of foodborne disease outbreaks may be challenging even after establishing the source of infection. An outbreak of Salmonella Typhimurium U323 infections occurred in Denmark from March to September 2010, involving 172 cases. Before the detection of human cases, severa...... ready-to-eat spreadable pork sausage (teewurst) as the source of a sub-outbreak (matched odds ratio 17, 95% confidence interval 2·1–130)....... positive isolates of the outbreak strain had been found in a particular pig slaughterhouse and thus early traceback, investigation and control measures were possible. Several batches of pork and pork products were recalled and the slaughterhouse was closed twice for disinfection. No single common food item...

Characterization of the influenza A H5N1 viruses of the 2008-09 outbreaks in India reveals a third introduction and possible endemicity.

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Alok K Chakrabarti

Full Text Available Widespread infection of highly pathogenic avian influenza A H5N1 was reported from backyard and commercial poultry in West Bengal (WB, an eastern state of India in early 2008. Infection gradually spread to Tripura, Assam and Sikkim, the northeastern states, with 70 outbreaks reported between January 2008 and May 2009. Whole genome sequence analysis of three isolates from WB, one isolate from Tripura along with the analysis of hemagglutinin (HA and neuraminidase (NA genes of 17 other isolates was performed during this study. In the HA gene phylogenetic tree, all the 2008-09 Indian isolates belonged to EMA3 sublineage of clade 2.2. The closest phylogenetic relationship was found to be with the 2007-09 isolates from Bangladesh and not with the earlier 2006 and 2007 Indian isolates implying a third introduction into the country. The receptor-binding pocket of HA1 of two isolates from WB showed S221P mutation, one of the markers predicted to be associated with human receptor specificity. Two substitutions E119A (2 isolates of WB and N294S (2 other isolates of WB known to confer resistance to NA inhibitors were observed in the active site of neuraminidase. Several additional mutations were observed within the 2008-09 Indian isolates indicating genetic diversification. Overall, the study is indicative of a possible endemicity in the eastern and northeastern parts of the country, demanding active surveillance specifically in view of the critical mutations that have been observed in the influenza A H5N1 viruses.

Who is that masked person: the use of face masks on Mexico City public transportation during the Influenza A (H1N1) outbreak.

Science.gov (United States)

Condon, Bradly John; Sinha, Tapen

2010-04-01

This article examines three issues: (1) the use, over time, of facemasks in a public setting to prevent the spread of a respiratory disease for which the mortality rate is unknown; (2) the difference between the responses of male and female subjects in a public setting to unknown risks; and (3) the effectiveness of mandatory and voluntary public health measures in a public health emergency. The use of facemasks to prevent the spread of respiratory diseases in a public setting is controversial. At the height of the influenza epidemic in Mexico City in the spring of 2009, the federal government of Mexico recommended that passengers on public transport use facemasks to prevent contagion. The Mexico City government made the use of facemasks mandatory for bus and taxi drivers, but enforcement procedures differed for these two categories. Using an evidence-based approach, we collected data on the use of facemasks over a 2-week period. In the specific context of the Mexico City influenza outbreak, these data showed mask usage rates mimicked the course of the epidemic and gender difference in compliance rates among metro passengers. Moreover, there was not a significant difference in compliance with mandatory and voluntary public health measures where the effect of the mandatory measures was diminished by insufficiently severe penalties, the lack of market forces to create compliance incentives and sufficient political influence to diminish enforcement. Voluntary compliance was diminished by lack of trust in the government. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Impact of Human Immunodeficiency Virus on the Burden and Severity of Influenza Illness in Malawian Adults: A Prospective Cohort and Parallel Case-Control Study.

Science.gov (United States)

Ho, Antonia; Aston, Stephen J; Jary, Hannah; Mitchell, Tamara; Alaerts, Maaike; Menyere, Mavis; Mallewa, Jane; Nyirenda, Mulinda; Everett, Dean; Heyderman, Robert S; French, Neil

2018-03-05

The impact of human immunodeficiency virus (HIV) infection on influenza incidence and severity in adults in sub-Saharan Africa is unclear. Seasonal influenza vaccination is recommended for HIV-infected persons in developed settings but is rarely implemented in Africa. We conducted a prospective cohort study to compare the incidence of laboratory-confirmed influenza illness between HIV-infected and HIV-uninfected adults in Blantyre, Malawi. In a parallel case-control study, we explored risk factors for severe influenza presentation of severe (hospitalized) lower respiratory tract infection, and mild influenza (influenza-like illness [ILI]). The cohort study enrolled 608 adults, of whom 360 (59%) were HIV infected. Between April 2013 and March 2015, 24 of 229 ILI episodes (10.5%) in HIV-infected and 5 of 119 (4.2%) in HIV-uninfected adults were positive for influenza by means of polymerase chain reaction (incidence rate, 46.0 vs 14.5 per 1000 person-years; incidence rate ratio, 2.75; 95% confidence interval, 1.02-7.44; P = .03; adjusted for age, sex, household crowding, and food security). In the case-control study, influenza was identified in 56 of 518 patients (10.8%) with hospitalized lower respiratory tract infection, and 88 or 642 (13.7%) with ILI. The HIV prevalence was 69.6% and 29.6%, respectively, among influenza-positive case patients and controls. HIV was a significant risk factor for severe influenza (odds ratio, 4.98; 95% confidence interval, 2.09-11.88; P factor for influenza-associated ILI and severe presentation in this high-HIV prevalence African setting. Targeted influenza vaccination of HIV-infected African adults should be reevaluated, and the optimal mechanism for vaccine introduction in overstretched health systems needs to be determined. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

A-equi-2 influenza in horses in the Republic of South Africa.

Science.gov (United States)

Rogers, A L

1988-06-01

In early December 1986 A-equi-2 influenza virus was isolated for the first time in the Republic of South Africa. All horses were susceptible to the highly contagious aerosol-borne orthomyxovirus resulting in widespread outbreaks of equine influenza with typical primary respiratory symptoms. Treatment consisted of rest, anti-inflammatory drugs, antibiotics and good nursing. Future protection can be obtained by vaccination.

Influenza vaccination

DEFF Research Database (Denmark)

Østerhus, Sven Frederick

2015-01-01

The Cochrane Library was systematically searched for meta-analyses regarding influenza vaccination of various populations, both healthy and sick. An effect in reducing the number of cases of influenza, influenza-like illness or complications to influenza was found in some studies, but, generally......, the quality of the studies was low, and several studies lacked hard clinical endpoints. Data on adverse effects were scarce. More randomised controlled trials investigating the effects of influenza vaccination are warranted....

Radiographic study of severe Influenza-A (H1N1) disease in children

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Zhao Cailei, E-mail: zhaocailei197866@163.com [Department of Radiology, Shenzhen Children' s Hospital, No. 7019, Yitian Road, Futian District, Shenzhen 518026 (China); Gan Yungen, E-mail: mickeyym@yahoo.cn [Department of Radiology, Shenzhen Children' s Hospital, No. 7019, Yitian Road, Futian District, Shenzhen 518026 (China); Sun Jie, E-mail: sunxixi@21cn.com [Department of Radiology, Shenzhen Children' s Hospital, No. 7019, Yitian Road, Futian District, Shenzhen 518026 (China)

2011-09-15

Objective: To characterize the radiographic findings of pediatric patients with severe Influenza-A (H1N1) disease. Methods: A retrospective study of data from chest X-ray, CT and MRI exam of 29 pediatric patients treated in intensive care unit for severe Influenza-A (H1N1) disease. Results: Disease developed quickly at early stage. Here are four types of radiographic findings. The disease continued to progress for 2-3 days and X-ray showed that all 29 patients had increased solid lesions with the existence of interstitial lesions. Four days later, all lung lesions showed absorption to certain degree. Fifteen days later, X-ray and CT showed complete or significant absorption in 19 cases (85.5%); delayed recovery was identified in 8 cases (27.6%), pulmonary fibrosis was found in 3 cases (10.3%), and 3 patients (10.3%) died. But the latter identified more lesions. Cranial CT and MRI were performed for 8 patients who had neurological symptoms. Of them, 3 cases (10.3%) were abnormal, showed symmetrical long T1 and T2 signal shadow in bilateral thalamus and longer T1 and T2 signals in the between. 3 cases had autopsy completed. Conclusion: The severe Influenza-A (H1N1) among children progression was generally rapid in the first 3 days. The overall radiographic findings are similar to acute respiratory distress syndrome (ARDS). A small portion of the patients occurred acute necrotizing encephalopathy and plastic bronchitis.

Radiographic study of severe Influenza-A (H1N1) disease in children

International Nuclear Information System (INIS)

Zhao Cailei; Gan Yungen; Sun Jie

2011-01-01

Objective: To characterize the radiographic findings of pediatric patients with severe Influenza-A (H1N1) disease. Methods: A retrospective study of data from chest X-ray, CT and MRI exam of 29 pediatric patients treated in intensive care unit for severe Influenza-A (H1N1) disease. Results: Disease developed quickly at early stage. Here are four types of radiographic findings. The disease continued to progress for 2-3 days and X-ray showed that all 29 patients had increased solid lesions with the existence of interstitial lesions. Four days later, all lung lesions showed absorption to certain degree. Fifteen days later, X-ray and CT showed complete or significant absorption in 19 cases (85.5%); delayed recovery was identified in 8 cases (27.6%), pulmonary fibrosis was found in 3 cases (10.3%), and 3 patients (10.3%) died. But the latter identified more lesions. Cranial CT and MRI were performed for 8 patients who had neurological symptoms. Of them, 3 cases (10.3%) were abnormal, showed symmetrical long T1 and T2 signal shadow in bilateral thalamus and longer T1 and T2 signals in the between. 3 cases had autopsy completed. Conclusion: The severe Influenza-A (H1N1) among children progression was generally rapid in the first 3 days. The overall radiographic findings are similar to acute respiratory distress syndrome (ARDS). A small portion of the patients occurred acute necrotizing encephalopathy and plastic bronchitis.

USGS highly pathogenic avian influenza research strategy

Science.gov (United States)

Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

2015-09-09

Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

Annually repeated influenza vaccination improves humoral responses to several influenza virus strains in healthy elderly

NARCIS (Netherlands)

I.A. de Bruijn (Iris); E.J. Remarque (Edmond); W.E.Ph. Beyer (Walter); S. le Cessie (Saskia); N. Masurel (Nic); G.L. Ligthart (Gerard)

1997-01-01

textabstractThe benefit of annually repeated influenza vaccination on antibody formation is still under debate. In this study the effect of annually repeated influenza vaccination on haemagglutination inhibiting (HI) antibody formation in the elderly is investigated. Between 1990 and 1993 healthy

Heterogeneous virulence of pandemic 2009 influenza H1N1 virus in mice

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Farooqui Amber

2012-06-01

Full Text Available Abstract Background Understanding the pathogenesis of influenza infection is a key factor leading to the prevention and control of future outbreaks. Pandemic 2009 Influenza H1N1 infection, although frequently mild, led to a severe and fatal form of disease in certain cases that make its virulence nature debatable. Much effort has been made toward explaining the determinants of disease severity; however, no absolute reason has been established. Results This study presents the heterogeneous virulence of clinically similar strains of pandemic 2009 influenza virus in human alveolar adenocarcinoma cells and mice. The viruses were obtained from patients who were admitted in a local hospital in China with a similar course of infection and recovered. The A/Nanchang/8002/2009 and A/Nanchang/8011/2009 viruses showed efficient replication and high lethality in mice while infection with A/Nanchang/8008/2009 was not lethal with impaired viral replication, minimal pathology and modest proinflammatory activity in lungs. Sequence analysis displayed prominent differences between polymerase subunits (PB2 and PA of viral genomes that might correlate with their different phenotypic behavior. Conclusions The study confirms that biological heterogeneity, linked with the extent of viral replication, exists among pandemic H1N1 strains that may serve as a benchmark for future investigations on influenza pathogenesis.

Contemporary North American influenza H7 viruses possess human receptor specificity: Implications for virus transmissibility

DEFF Research Database (Denmark)

Belser, Jessica A; Blixt, Ola; Chen, Li-Mei

2008-01-01

Avian H7 influenza viruses from both the Eurasian and North American lineage have caused outbreaks in poultry since 2002, with confirmed human infection occurring during outbreaks in The Netherlands, British Columbia, and the United Kingdom. The majority of H7 infections have resulted in self-lim...

Usefulness of CURB-65 and pneumonia severity index for influenza A H1N1v pneumonia.

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Estella, A

2012-01-01

Usefulness of CURB-65 and pneumonia severity index for influenza A H1N1v pneumonia. A. Estella. Different prognostic scales have been documented to assess the severity and indications for hospitalization and ICU admissions of community acquired pneumonia. During the past two years Influenza A H1N1v infections have been commonly attended to in emergency departments. The aim of the study was to analyse the usefulness of the application of the Pneumonia Severity Index (PSI) and CURB-65 prognostic scales in patients with primary viral pneumonia caused by influenza A H1N1v. A retrospective study was performed at a community hospital with a 17 bed-intensive care unit. Patients admitted in hospital with influenza A H1N1v pneumonia over a two year period were analysed. CURB 65 and PSI scales were applied in the emergency department and outcome and destination of admission were analysed. 24 patients were registered, 19 required ICU admission and 5 patients were admitted in medical wards. Most of the patients admitted to the intensive care unit (78.9%) required mechanical ventilation. Mortality was 21.1%. Most patients admitted to the ICU had CURB 65 scale of 1 (60%), 13.3% obtained 0 and 26.7% 2. PSI scale resulted class I in a 20%, class II 40%, 26.7% class IV and 13.3% class V. The scales CURB 65 and PSI showed no differences in scores according to the destination of admission and mortality. Use of CURB-65 and PSI in the emergency department may underestimate the risk of patients with Influenza A H1N1v pneumonia. Based in our results, the ability of these scales to predict ICU admissions for Influenza A H1N1v pneumonia is questioned.

Bringing influenza vaccines into the 21st century.

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Settembre, Ethan C; Dormitzer, Philip R; Rappuoli, Rino

2014-01-01

The recent H7N9 influenza outbreak in China highlights the need for influenza vaccine production systems that are robust and can quickly generate substantial quantities of vaccines that target new strains for pandemic and seasonal immunization. Although the influenza vaccine system, a public-private partnership, has been effective in providing vaccines, there are areas for improvement. Technological advances such as mammalian cell culture production and synthetic vaccine seeds provide a means to increase the speed and accuracy of targeting new influenza strains with mass-produced vaccines by dispensing with the need for egg isolation, adaptation, and reassortment of vaccine viruses. New influenza potency assays that no longer require the time-consuming step of generating sheep antisera could further speed vaccine release. Adjuvants that increase the breadth of the elicited immune response and allow dose sparing provide an additional means to increase the number of available vaccine doses. Together these technologies can improve the influenza vaccination system in the near term. In the longer term, disruptive technologies, such as RNA-based flu vaccines and 'universal' flu vaccines, offer a promise of a dramatically improved influenza vaccine system.

Avian Influenza: a global threat needing a global solution

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Koh GCH

2008-11-01

Full Text Available Abstract There have been three influenza pandemics since the 1900s, of which the 1919–1919 flu pandemic had the highest mortality rates. The influenza virus infects both humans and birds, and mutates using two mechanisms: antigenic drift and antigenic shift. Currently, the H5N1 avian flu virus is limited to outbreaks among poultry and persons in direct contact to infected poultry, but the mortality rate among infected humans is high. Avian influenza (AI is endemic in Asia as a result of unregulated poultry rearing in rural areas. Such birds often live in close proximity to humans and this increases the chance of genetic re-assortment between avian and human influenza viruses which may produce a mutant strain that is easily transmitted between humans. Once this happens, a global pandemic is likely. Unlike SARS, a person with influenza infection is contagious before the onset of case-defining symptoms which limits the effectiveness of case isolation as a control strategy. Researchers have shown that carefully orchestrated of public health measures could potentially limit the spread of an AI pandemic if implemented soon after the first cases appear. To successfully contain and control an AI pandemic, both national and global strategies are needed. National strategies include source surveillance and control, adequate stockpiles of anti-viral agents, timely production of flu vaccines and healthcare system readiness. Global strategies such as early integrated response, curbing the disease outbreak at source, utilization of global resources, continuing research and open communication are also critical.

Descriptive epidemiology of equine influenza in India (2008-2009: temporal and spatial trends

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Partap S. Narwal

2010-12-01

Full Text Available Equine influenza is a contagious viral disease that affects all members of the family Equidae, i.e. horses, donkeys and mules. The authors describe the pattern of equine influenza outbreaks in a number of states of India from July 2008 to June 2009. The disease was first reported in June 2008 in Katra (Jammu and Kashmir and spread to ten other states within a year. All outbreaks of equine influenza in the various states were confirmed by laboratory investigations (virus isolation and/or serological confirmation based on haemagglutination inhibition [HI] assays of paired samples before declaring them as equine influenza virus-affected state(s. The virus (H3N8 was reported from various locations in the country including Katra, Mysore (Karnataka, Ahmedabad (Gujarat, Gopeshwar and Uttarkashi (Uttarakhand and was isolated in 9- to 11-day-old embryonated chicken eggs. The virus was confirmed as H3N8 by HI assays with standard serum and amplification of full-length haemagglutinin and neuraminidase genes by reverse transcriptase-polymerase chain reaction. Serum samples (n = 4 740 of equines from 13 states in India screened by HI revealed 1 074 (22.65% samples as being positive for antibodies to equine influenza virus (H3N8.

An overview of the recent outbreaks of the avian-origin influenza A (H7N9) virus in the human.

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Tang, Ren-Bin; Chen, Hui-Lan

2013-05-01

Since the first human infection with influenza A (H7N9) viruses have been identified in Shanghai on March 31, 2013, the latest variant of the avian flu virus has spread across four Chinese provinces recently. Human infections with avian influenza are rare and this is the first time that human infection with a low pathogenic avian influenza A virus has been associated with fatal outcome. To date (May 5(th), 2013), China had reported 128 confirmed H7N9 infections in human, among 27 died. Most reported cases have severe respiratory illness resulting in severe pneumonia and in some cases have died. No evidence of sustained human-to -humans at this time, however, there is one family cluster with two confirmed cases for which human-to-human transmission cannot be ruled out. Recent evidence showed that the gene sequences of this novel H7N9 virus is primarily zoonotic and may be better adapted than other avian influenza viruses to infect human. Effective global infection control is urgently needed, and further surveillance and analyses should be undertaken to identify the source and mode of transmission of these viruses. Copyright © 2013. Published by Elsevier B.V.

Universal antibodies against the highly conserved influenza fusion peptide cross-neutralize several subtypes of influenza A virus

Energy Technology Data Exchange (ETDEWEB)

Hashem, Anwar M. [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Department of Microbiology, Faculty of Medicine, King Abdulaziz University, Jeddah (Saudi Arabia); Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON (Canada); Van Domselaar, Gary [National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB (Canada); Li, Changgui; Wang, Junzhi [National Institute for the Control of Pharmaceutical and Biological Products, Beijing (China); She, Yi-Min; Cyr, Terry D. [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Sui, Jianhua [Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, 44 Binney Street, Boston, MA 02115 (United States); He, Runtao [National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB (Canada); Marasco, Wayne A. [Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, 44 Binney Street, Boston, MA 02115 (United States); Li, Xuguang, E-mail: Sean.Li@hc-sc.gc.ca [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON (Canada)

2010-12-10

Research highlights: {yields} The fusion peptide is the only universally conserved epitope in all influenza viral hemagglutinins. {yields} Anti-fusion peptide antibodies are universal antibodies that cross-react with all influenza HA subtypes. {yields} The universal antibodies cross-neutralize different influenza A subtypes. {yields} The universal antibodies inhibit the fusion process between the viruses and the target cells. -- Abstract: The fusion peptide of influenza viral hemagglutinin plays a critical role in virus entry by facilitating membrane fusion between the virus and target cells. As the fusion peptide is the only universally conserved epitope in all influenza A and B viruses, it could be an attractive target for vaccine-induced immune responses. We previously reported that antibodies targeting the first 14 amino acids of the N-terminus of the fusion peptide could bind to virtually all influenza virus strains and quantify hemagglutinins in vaccines produced in embryonated eggs. Here we demonstrate that these universal antibodies bind to the viral hemagglutinins in native conformation presented in infected mammalian cell cultures and neutralize multiple subtypes of virus by inhibiting the pH-dependant fusion of viral and cellular membranes. These results suggest that this unique, highly-conserved linear sequence in viral hemagglutinin is exposed sufficiently to be attacked by the antibodies during the course of infection and merits further investigation because of potential importance in the protection against diverse strains of influenza viruses.

Universal antibodies against the highly conserved influenza fusion peptide cross-neutralize several subtypes of influenza A virus

International Nuclear Information System (INIS)

Hashem, Anwar M.; Van Domselaar, Gary; Li, Changgui; Wang, Junzhi; She, Yi-Min; Cyr, Terry D.; Sui, Jianhua; He, Runtao; Marasco, Wayne A.; Li, Xuguang

2010-01-01

Research highlights: → The fusion peptide is the only universally conserved epitope in all influenza viral hemagglutinins. → Anti-fusion peptide antibodies are universal antibodies that cross-react with all influenza HA subtypes. → The universal antibodies cross-neutralize different influenza A subtypes. → The universal antibodies inhibit the fusion process between the viruses and the target cells. -- Abstract: The fusion peptide of influenza viral hemagglutinin plays a critical role in virus entry by facilitating membrane fusion between the virus and target cells. As the fusion peptide is the only universally conserved epitope in all influenza A and B viruses, it could be an attractive target for vaccine-induced immune responses. We previously reported that antibodies targeting the first 14 amino acids of the N-terminus of the fusion peptide could bind to virtually all influenza virus strains and quantify hemagglutinins in vaccines produced in embryonated eggs. Here we demonstrate that these universal antibodies bind to the viral hemagglutinins in native conformation presented in infected mammalian cell cultures and neutralize multiple subtypes of virus by inhibiting the pH-dependant fusion of viral and cellular membranes. These results suggest that this unique, highly-conserved linear sequence in viral hemagglutinin is exposed sufficiently to be attacked by the antibodies during the course of infection and merits further investigation because of potential importance in the protection against diverse strains of influenza viruses.

Avian Influenza in Migratory Birds : Regional Surveillance and ...

International Development Research Centre (IDRC) Digital Library (Canada)

Outbreaks may only occur after transmission from migratory species to domestic flocks through local amplification and secondary spread through the movement of poultry or people, as well as equipment or vehicles contaminated by sick birds. The Asia Partnership for Avian Influenza Research (APAIR) brings together ...

Presence of serum antibodies to influenza A subtypes H5 and N1 in swans and ibises in French wetlands, irrespective of highly pathogenic H5N1 natural infection.

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Niqueux, Eric; Guionie, Olivier; Schmitz, Audrey; Hars, Jean; Jestin, Véronique

2010-03-01

Highly pathogenic (HP) avian influenza A viruses (AIVs) subtype H5N1 (subclade 2.2) were detected in wild birds during outbreaks in France during winter 2006 and summer 2007 in la Dombes wetlands (eastern France) and in Moselle wetlands (northeastern France), respectively. Blood samples from apparently healthy wild birds were collected in 2006 and 2007 from the end of the outbreak to several weeks after the influenza A outbreak inside and outside the contaminated areas, and in 2008 outside the contaminated areas. The samples were tested for the presence and/or quantitation of serum antibodies to influenza A subtypes H5 and N1 using hemagglutination inhibition tests (HITs), a commercial N1-specific enzyme-linked immunosorbent assay kit, and virus neutralization assay. In the HIT, low pathogenicity (LP) and HP H5 AIVs (belonging to H5N1, H5N2, and H5N3 subtypes) were used as antigens. One hundred mute swans were bled in the la Dombes outbreak area in 2006. During 2007, 46 mallards, 69 common pochards, and 59 mute swans were sampled in the Moselle outbreak area. For comparison, blood samples were also collected in 2007 from 60 mute swans from the Marne department where no HP H5N1 influenza A cases have been reported, and in 2008 from 111 sacred ibises in western France where no HP H5N1 influenza A infections in wild birds have been reported either. Mute swans (irrespective of their origin and time of sampling) and sacred ibises (from an area with no known outbreaks) had the highest prevalence of positive sera in the H5 HIT (49-69% and 64%, respectively). The prevalence of anti-H5 antibodies in mallards and common pochards was lower (28% and 27%, respectively). Positive H5- and N1-antibody responses were also significantly associated in swans (irrespective of their origin and time of sampling) and in sacred ibises. However, in swans from the area without outbreaks, the HIT titer against an H5N1 LPAIV was significantly higher than against an H5N1 2.2.1 HPAIV, whereas no

Detection of Influenza C Viruses Among Outpatients and Patients Hospitalized for Severe Acute Respiratory Infection, Minnesota, 2013-2016.

Science.gov (United States)

Thielen, Beth K; Friedlander, Hannah; Bistodeau, Sarah; Shu, Bo; Lynch, Brian; Martin, Karen; Bye, Erica; Como-Sabetti, Kathryn; Boxrud, David; Strain, Anna K; Chaves, Sandra S; Steffens, Andrea; Fowlkes, Ashley L; Lindstrom, Stephen; Lynfield, Ruth

2018-03-19

Existing literature suggests that influenza C typically causes mild respiratory tract disease. However, clinical and epidemiological data are limited. Four outpatient clinics and 3 hospitals submitted clinical data and respiratory specimens through a surveillance network for acute respiratory infection (ARI) from May 2013 through December 2016. Specimens were tested using multitarget nucleic acid amplification for 19-22 respiratory pathogens, including influenza C. Influenza C virus was detected among 59 of 10 202 (0.58%) hospitalized severe ARI cases and 11 of 2282 (0.48%) outpatients. Most detections occurred from December to March, 73% during the 2014-2015 season. Influenza C detections occurred among patients of all ages, with rates being similar between inpatients and outpatients. The highest rate of detection occurred among children aged 6-24 months (1.2%). Among hospitalized cases, 7 required intensive care. Medical comorbidities were reported in 58% of hospitalized cases and all who required intensive care. At least 1 other respiratory pathogen was detected in 40 (66%) cases, most commonly rhinovirus/enterovirus (25%) and respiratory syncytial virus (20%). The hemagglutinin-esterase-fusion gene was sequenced in 37 specimens, and both C/Kanagawa and C/Sao Paulo lineages were detected in inpatients and outpatients. We found seasonal circulation of influenza C with year-to-year variability. Detection was most frequent among young children but occurred in all ages. Some cases that were positive for influenza C, particularly those with comorbid conditions, had severe disease, suggesting a need for further study of the role of influenza C virus in the pathogenesis of respiratory disease.

Agro-environmental determinants of avian influenza circulation: a multisite study in Thailand, Vietnam and Madagascar.

Science.gov (United States)

Paul, Mathilde C; Gilbert, Marius; Desvaux, Stéphanie; Andriamanivo, Harena Rasamoelina; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Véronique

2014-01-01

Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 2004-2005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced.

Fluorescent immunochromatography for rapid and sensitive typing of seasonal influenza viruses.

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Akira Sakurai

Full Text Available Lateral flow tests also known as Immunochromatography (IC is an antigen-detection method conducted on a nitrocellulose membrane that can be completed in less than 20 min. IC has been used as an important rapid test for clinical diagnosis and surveillance of influenza viruses, but the IC sensitivity is relatively low (approximately 60% and the limit of detection (LOD is as low as 10³ pfu per reaction. Recently, we reported an improved IC assay using antibodies conjugated with fluorescent beads (fluorescent immunochromatography; FLIC for subtyping H5 influenza viruses (FLIC-H5. Although the FLIC strip must be scanned using a fluorescent reader, the sensitivity (LOD is significantly improved over that of conventional IC methods. In addition, the antibodies which are specific against the subtypes of influenza viruses cannot be available for the detection of other subtypes when the major antigenicity will be changed. In this study, we established the use of FLIC to type seasonal influenza A and B viruses (FLIC-AB. This method has improved sensitivity to 100-fold higher than that of conventional IC methods when we used several strains of influenza viruses. In addition, FLIC-AB demonstrated the ability to detect influenza type A and influenza type B viruses from clinical samples with high sensitivity and specificity (Type A: sensitivity 98.7% (74/75, specificity 100% (54/54, Type B: sensitivity 100% (90/90, specificity 98.2% (54/55 in nasal swab samples in comparison to the results of qRT-PCR. And furthermore, FLIC-AB performs better in the detection of early stage infection (under 13 h than other conventional IC methods. Our results provide new strategies to prevent the early-stage transmission of influenza viruses in humans during both seasonal outbreaks and pandemics.

Pandemic (H1N1 2009 Influenza Virus Infection in A Survivor who has recovered from severe H7N9 Virus Infection, China

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Shan-Hui Chen

2016-10-01

Full Text Available We firstly report a patient who presented with severe complications after infection with influenza A(H1N1 pdm2009, more than one year after recovery from severe H7N9 virus infections. The population of patients who recovered from severe H7N9 infections might be at a higher risk to suffer severe complications after seasonal influenza infections, and they should be included in the high-risk populations recommended to receive seasonal influenza vaccination.

Mitigation strategies for pandemic influenza A: balancing conflicting policy objectives.

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T Déirdre Hollingsworth

Full Text Available Mitigation of a severe influenza pandemic can be achieved using a range of interventions to reduce transmission. Interventions can reduce the impact of an outbreak and buy time until vaccines are developed, but they may have high social and economic costs. The non-linear effect on the epidemic dynamics means that suitable strategies crucially depend on the precise aim of the intervention. National pandemic influenza plans rarely contain clear statements of policy objectives or prioritization of potentially conflicting aims, such as minimizing mortality (depending on the severity of a pandemic or peak prevalence or limiting the socio-economic burden of contact-reducing interventions. We use epidemiological models of influenza A to investigate how contact-reducing interventions and availability of antiviral drugs or pre-pandemic vaccines contribute to achieving particular policy objectives. Our analyses show that the ideal strategy depends on the aim of an intervention and that the achievement of one policy objective may preclude success with others, e.g., constraining peak demand for public health resources may lengthen the duration of the epidemic and hence its economic and social impact. Constraining total case numbers can be achieved by a range of strategies, whereas strategies which additionally constrain peak demand for services require a more sophisticated intervention. If, for example, there are multiple objectives which must be achieved prior to the availability of a pandemic vaccine (i.e., a time-limited intervention, our analysis shows that interventions should be implemented several weeks into the epidemic, not at the very start. This observation is shown to be robust across a range of constraints and for uncertainty in estimates of both R(0 and the timing of vaccine availability. These analyses highlight the need for more precise statements of policy objectives and their assumed consequences when planning and implementing strategies

Antiviral Activities of Several Oral Traditional Chinese Medicines against Influenza Viruses.

Science.gov (United States)

Ma, Lin-Lin; Ge, Miao; Wang, Hui-Qiang; Yin, Jin-Qiu; Jiang, Jian-Dong; Li, Yu-Huan

2015-01-01

Influenza is still a serious threat to human health with significant morbidity and mortality. The emergence of drug-resistant influenza viruses poses a great challenge to existing antiviral drugs. Traditional Chinese medicines (TCMs) may be an alternative to overcome the challenge. Here, 10 oral proprietary Chinese medicines were selected to evaluate their anti-influenza activities. These drugs exhibit potent inhibitory effects against influenza A H1N1, influenza A H3N2, and influenza B virus. Importantly, they demonstrate potent antiviral activities against drug-resistant strains. In the study of mechanisms, we found that Xiaoqinglong mixture could increase antiviral interferon production by activating p38 MAPK, JNK/SAPK pathway, and relative nuclear transcription factors. Lastly, our studies also indicate that some of these medicines show inhibitory activities against EV71 and CVB strains. In conclusion, the 10 traditional Chinese medicines, as kind of compound combination medicines, show broad-spectrum antiviral activities, possibly also including inhibitory activities against strains resistant to available antiviral drugs.

Risk factors for exposure to influenza a viruses, including subtype H5 viruses, in Thai free-grazing ducks.

Science.gov (United States)

Beaudoin, A L; Kitikoon, P; Schreiner, P J; Singer, R S; Sasipreeyajan, J; Amonsin, A; Gramer, M R; Pakinsee, S; Bender, J B

2014-08-01

Free-grazing ducks (FGD) have been associated with highly pathogenic avian influenza (HPAI) H5N1 outbreaks and may be a viral reservoir. In July-August 2010, we assessed influenza exposure of Thai FGD and risk factors thereof. Serum from 6254 ducks was analysed with enzyme-linked immunosorbent assay (ELISA) to detect antibodies to influenza A nucleoprotein (NP), and haemagglutinin H5 protein. Eighty-five per cent (5305 ducks) were seropositive for influenza A. Of the NP-seropositive sera tested with H5 assays (n = 1423), 553 (39%) were H5 ELISA positive and 57 (4%) suspect. Twelve per cent (74 of 610) of H5 ELISA-positive/suspect ducks had H5 titres ≥ 1 : 20 by haemagglutination inhibition. Risk factors for influenza A seropositivity include older age, poultry contact, flock visitors and older purchase age. Study flocks had H5 virus exposure as recently as March 2010, but no HPAI H5N1 outbreaks have been identified in Thailand since 2008, highlighting a need for rigorous FGD surveillance. © 2012 Blackwell Verlag GmbH.

Antibody Persistence in Adults Two Years after Vaccination with an H1N1 2009 Pandemic Influenza Virus-Like Particle Vaccine.

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Nuriban Valero-Pacheco

Full Text Available The influenza virus is a human pathogen that causes epidemics every year, as well as potential pandemic outbreaks, as occurred in 2009. Vaccination has proven to be sufficient in the prevention and containment of viral spreading. In addition to the current egg-based vaccines, new and promising vaccine platforms, such as cell culture-derived vaccines that include virus-like particles (VLPs, have been developed. VLPs have been shown to be both safe and immunogenic against influenza infections. Although antibody persistence has been studied in traditional egg-based influenza vaccines, studies on antibody response durations induced by VLP influenza vaccines in humans are scarce. Here, we show that subjects vaccinated with an insect cell-derived VLP vaccine, in the midst of the 2009 H1N1 influenza pandemic outbreak in Mexico City, showed antibody persistence up to 24 months post-vaccination. Additionally, we found that subjects that reported being revaccinated with a subsequent inactivated influenza virus vaccine showed higher antibody titres to the pandemic influenza virus than those who were not revaccinated. These findings provide insights into the duration of the antibody responses elicited by an insect cell-derived pandemic influenza VLP vaccine and the possible effects of subsequent influenza vaccination on antibody persistence induced by this VLP vaccine in humans.

Genetic changes that accompanied shifts of low pathogenic avian influenza viruses toward higher pathogenicity in poultry

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Abdelwhab, El-Sayed M; Veits, Jutta; Mettenleiter, Thomas C

2013-01-01

Avian influenza viruses (AIV) of H5 and H7 subtypes exhibit two different pathotypes in poultry: infection with low pathogenic (LP) strains results in minimal, if any, health disturbances, whereas highly pathogenic (HP) strains cause severe morbidity and mortality. LPAIV of H5 and H7 subtypes can spontaneously mutate into HPAIV. Ten outbreaks caused by HPAIV are known to have been preceded by circulation of a predecessor LPAIV in poultry. Three of them were caused by H5N2 subtype and seven involved H7 subtype in combination with N1, N3, or N7. Here, we review those outbreaks and summarize the genetic changes which resulted in the transformation of LPAIV to HPAIV under natural conditions. Mutations that were found directly in those outbreaks are more likely to be linked to virulence, pathogenesis, and early adaptation of AIV. PMID:23863606

Severe Dengue Fever Outbreak in Taiwan.

Science.gov (United States)

Wang, Sheng-Fan; Wang, Wen-Hung; Chang, Ko; Chen, Yen-Hsu; Tseng, Sung-Pin; Yen, Chia-Hung; Wu, Deng-Chyang; Chen, Yi-Ming Arthur

2016-01-01

Dengue fever (DF) is a vector-borne disease caused by dengue viruses (DENVs). Epidemic dengue occurs intermittently in Taiwan. In 2014, Taiwan experienced its largest DF outbreak. There were 15,732 DF cases reported. There were a total of 136 dengue hemorrhagic fever (DHF) cases, of which 20 resulted in death. Most DF cases were reported in southern Taiwan. A total of 15,043 (96%) cases were from Kaohsiung, a modern city in southern Taiwan. This report reviews DF epidemics in Taiwan during 2005-2014. The correlation between DF and DHF along with temperature and precipitation were conjointly examined. We conclude that most dengue epidemics in Taiwan resulted from imported DF cases. Results indicate three main factors that may have been associated with this DF outbreak in Kaohsiung: an underground pipeline explosion combined with subsequent rainfall and higher temperature. These factors may have enhanced mosquito breeding activity, facilitating DENV transmission. © The American Society of Tropical Medicine and Hygiene.

The Use of Ambient Humidity Conditions to Improve Influenza Forecast

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Shaman, J. L.; Kandula, S.; Yang, W.; Karspeck, A. R.

2017-12-01

Laboratory and epidemiological evidence indicate that ambient humidity modulates the survival and transmission of influenza. Here we explore whether the inclusion of humidity forcing in mathematical models describing influenza transmission improves the accuracy of forecasts generated with those models. We generate retrospective forecasts for 95 cities over 10 seasons in the United States and assess both forecast accuracy and error. Overall, we find that humidity forcing improves forecast performance and that forecasts generated using daily climatological humidity forcing generally outperform forecasts that utilize daily observed humidity forcing. These findings hold for predictions of outbreak peak intensity, peak timing, and incidence over 2- and 4-week horizons. The results indicate that use of climatological humidity forcing is warranted for current operational influenza forecast and provide further evidence that humidity modulates rates of influenza transmission.

Population genetics of IFITM3 in Portugal and Central Africa reveals a potential modifier of influenza severity.

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David, Susana; Correia, Vanessa; Antunes, Liliana; Faria, Ricardo; Ferrão, José; Faustino, Paula; Nunes, Baltazar; Maltez, Fernando; Lavinha, João; Rebelo de Andrade, Helena

2018-03-01

Influenza epidemics are a serious global public health and economic problem. The IFITM3 allele (rs12252-C) was suggested as a population-based genetic risk factor for severe influenza virus infection by A(H1N1)pdm09. We analyzed the population genetics of IFITM3 variants in the Portuguese general population (n = 200) and Central Africans (largely Angolan) (n = 148) as well as its association to influenza severity in Portuguese patients (n = 41). Seven SNPs, within the 352 bp IFITM3 amplicon around rs12252, were identified. SNP distributions in the Portuguese appeared at an intermediate level between the Africans and other Europeans. According to HapMap, rs34481144 belongs to the same linkage disequilibrium (LD) block as rs12252 and is in strong LD with rs6421983. A negative association with severe relative to mild disease was observed for allele rs34481144-A, indicating a protective effect under the dominant model. Moreover, haplotype Hap4 with rs34481144-A, not including rs12252-C, was significantly associated to mild influenza. Conversely, although with borderline significance, haplotype Hap1 with rs34481144-G, not including rs12252-C, was associated to severe disease. Moreover, in comparison to the general Portuguese population, statistical significant differences in the frequencies of the protective allele rs34481144-A in the severe disease group, the deleterious Hap1 in the mild disease group, and the protective Hap4 in the severe disease group were observed. The population attributable risk (PAR) for the targeted rs34481144 allele or genotype was of 55.91 and 64.44% in the general population and the mildly infected individuals, respectively. Implication of these variants in disease phenotype needs further validation, namely through functional analysis as is discussed.

Performance of clinical signs in poultry for the detection of outbreaks during the avian influenza A (H7N7) epidemic in The Netherlands in 2003.

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Elbers, Armin R W; Koch, Guus; Bouma, Annemarie

2005-06-01

The aim of this study was to make an inventory of the clinical signs of high-pathogenicity avian influenza (HPAI), to facilitate the development of an operational syndrome-reporting system (SRS) in The Netherlands as an early warning system for HPAI outbreaks. A total of 537 poultry flocks (240 infected and 297 non-infected) with a clinical suspicion of an infection with HPAI virus were investigated with respect to the clinical signs observed. Standardized reports were analysed with respect to observed clinical signs in the flocks. Various poultry types were distinguished. In infected commercial flocks with egg-producing chickens, the presence of increased mortality, apathy, coughing, reduction in normal vocalization, or pale eggs appeared to be overall the most sensitive indicators to detect a HPAI outbreak, matching a sensitivity of 99% with a specificity of 23%. In infected turkey flocks, the presence of apathy, decreased growth performance, reduction of normal vocalization, swollen sinuses, yawning, huddling, mucosal production from the beak, or lying down with an extended neck appeared to be overall the most sensitive indicators to detect a HPAI outbreak, matching a sensitivity of 100% with a specificity of 79%. In infected backyard/hobby flocks, increased mortality or swollen head appeared to be overall the most sensitive indicators of a HPAI outbreak, matching a sensitivity of 100% with a specificity of 26%. These results indicate that there is a solid basis for the choice of using increased mortality in the operational SRS in The Netherlands as an early warning system for HPAI outbreaks. The presence of apathy, specifically for turkeys, should be added to the SRS as an indicator.

Influenza hospitalization epidemiology from a severe acute respiratory infection surveillance system in Jordan, January 2008?February 2014

OpenAIRE

Al?Abdallat, Mohammad; Dawson, Patrick; Haddadin, Aktham Jeries; El?Shoubary, Waleed; Dueger, Erica; Al?Sanouri, Tarek; Said, Mayar M.; Talaat, Maha

2016-01-01

Background Acute respiratory infections (ARIs) are a major cause of morbidity and mortality worldwide. Influenza typically contributes substantially to the burden of ARI, but only limited data are available on influenza activity and seasonality in Jordan. Methods Syndromic case definitions were used to identify individuals with severe acute respiratory infections (SARI) admitted to four sentinel hospitals in Jordan. Demographic and clinical data were collected. Nasopharyngeal and oropharyngea...

Nonlinear dynamics of avian influenza epidemic models.

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Liu, Sanhong; Ruan, Shigui; Zhang, Xinan

2017-01-01

Avian influenza is a zoonotic disease caused by the transmission of the avian influenza A virus, such as H5N1 and H7N9, from birds to humans. The avian influenza A H5N1 virus has caused more than 500 human infections worldwide with nearly a 60% death rate since it was first reported in Hong Kong in 1997. The four outbreaks of the avian influenza A H7N9 in China from March 2013 to June 2016 have resulted in 580 human cases including 202 deaths with a death rate of nearly 35%. In this paper, we construct two avian influenza bird-to-human transmission models with different growth laws of the avian population, one with logistic growth and the other with Allee effect, and analyze their dynamical behavior. We obtain a threshold value for the prevalence of avian influenza and investigate the local or global asymptotical stability of each equilibrium of these systems by using linear analysis technique or combining Liapunov function method and LaSalle's invariance principle, respectively. Moreover, we give necessary and sufficient conditions for the occurrence of periodic solutions in the avian influenza system with Allee effect of the avian population. Numerical simulations are also presented to illustrate the theoretical results. Copyright © 2016 Elsevier Inc. All rights reserved.

Estimation of the National Disease Burden of Influenza-Associated Severe Acute Respiratory Illness in Kenya and Guatemala: A Novel Methodology

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Katz, Mark A.; Lindblade, Kim A.; Njuguna, Henry; Arvelo, Wences; Khagayi, Sammy; Emukule, Gideon; Linares-Perez, Nivaldo; McCracken, John; Nokes, D. James; Ngama, Mwanajuma; Kazungu, Sidi; Mott, Joshua A.; Olsen, Sonja J.; Widdowson, Marc-Alain; Feikin, Daniel R.

2013-01-01

Background Knowing the national disease burden of severe influenza in low-income countries can inform policy decisions around influenza treatment and prevention. We present a novel methodology using locally generated data for estimating this burden. Methods and Findings This method begins with calculating the hospitalized severe acute respiratory illness (SARI) incidence for children Guatemala, using data from August 2009–July 2011. In Kenya (2009 population 38.6 million persons), the annual number of hospitalized influenza-associated SARI cases ranged from 17,129–27,659 for children Guatemala (2011 population 14.7 million persons), the annual number of hospitalized cases of influenza-associated pneumonia ranged from 1,065–2,259 (0.5–1.0 per 1,000 persons) among children Guatemala. This method can be performed in most low and lower-middle income countries. PMID:23573177

Framing risk in pandemic influenza policy and control.

Science.gov (United States)

Seetoh, Theresa; Liverani, Marco; Coker, Richard

2012-01-01

This article explores differing understandings of 'risk' in relation to pandemic influenza policy and control. After a preliminary overview of methodological and practical problems in risk analysis, ways in which risk was framed and managed in three historical cases were examined. The interdependence between scientific empiricism and political decision-making led to the mismanagement of the 1976 swine influenza scare in the USA. The 2004 H5N1 avian influenza outbreak in Thailand, on the other hand, was undermined by questions of national economic interest and concerns over global health security. Finally, the recent global emergency of pandemic influenza H1N1 in 2009 demonstrated the difficulties of risk management under a context of pre-established perceptions about the characteristics and inevitability of a pandemic. Following the analysis of these cases, a conceptual framework is presented to illustrate ways in which changing relationships between risk assessment, risk perception and risk management can result in differing policy strategies.

Induction of respiratory immune responses in the chicken; implications for development of mucosal avian influenza virus vaccines

NARCIS (Netherlands)

Geus, de E.D.; Rebel, J.M.J.; Vervelde, L.

2012-01-01

The risk and the size of an outbreak of avian influenza virus (AIV) could be restricted by vaccination of poultry. A vaccine used for rapid intervention during an AIV outbreak should be safe, highly effective after a single administration and suitable for mass application. In the case of AIV,

Lessons from the pandemic: the need for new tools for risk and outbreak communication.

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Abraham, Thomas

2011-10-17

The influenza pandemic of 2009 revealed shortcomings in the existing guidelines for risk and outbreak communication. Concepts such as building trust proved hard to achieve in practice, whereas other issues such as communicating through the internet and coping with the political fallout of disease outbreaks are not dealt with in existing guidelines. This article surveys the current guidelines and makes recommendations for additional tools and guidelines to be developed in four areas: integrating long-term behavior change models with outbreak communications; research to develop a better understanding of communicating through the internet; research to understand how to use communications to build trust; and developing guidelines and principles to understand the political nature of disease outbreaks.

Syndromic surveillance for local outbreaks of lower-respiratory infections: would it work?

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Cees C van den Wijngaard

2010-04-01

Full Text Available Although syndromic surveillance is increasingly used to detect unusual illness, there is a debate whether it is useful for detecting local outbreaks. We evaluated whether syndromic surveillance detects local outbreaks of lower-respiratory infections (LRIs without swamping true signals by false alarms.Using retrospective hospitalization data, we simulated prospective surveillance for LRI-elevations. Between 1999-2006, a total of 290762 LRIs were included by date of hospitalization and patients place of residence (>80% coverage, 16 million population. Two large outbreaks of Legionnaires disease in the Netherlands were used as positive controls to test whether these outbreaks could have been detected as local LRI elevations. We used a space-time permutation scan statistic to detect LRI clusters. We evaluated how many LRI-clusters were detected in 1999-2006 and assessed likely causes for the cluster-signals by looking for significantly higher proportions of specific hospital discharge diagnoses (e.g. Legionnaires disease and overlap with regional influenza elevations. We also evaluated whether the number of space-time signals can be reduced by restricting the scan statistic in space or time. In 1999-2006 the scan-statistic detected 35 local LRI clusters, representing on average 5 clusters per year. The known Legionnaires' disease outbreaks in 1999 and 2006 were detected as LRI-clusters, since cluster-signals were generated with an increased proportion of Legionnaires disease patients (p:<0.0001. 21 other clusters coincided with local influenza and/or respiratory syncytial virus activity, and 1 cluster appeared to be a data artifact. For 11 clusters no likely cause was defined, some possibly representing as yet undetected LRI-outbreaks. With restrictions on time and spatial windows the scan statistic still detected the Legionnaires' disease outbreaks, without loss of timeliness and with less signals generated in time (up to 42% decline.To our

Surveillance of low pathogenic novel H7N9 avian influenza in commercial poultry barns: detection of outbreaks and estimation of virus introduction time.

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Pinsent, Amy; Blake, Isobel M; White, Michael T; Riley, Steven

2014-08-01

Both high and low pathogenic subtype A avian influenza remain ongoing threats to the commercial poultry industry globally. The emergence of a novel low pathogenic H7N9 lineage in China presents itself as a new concern to both human and animal health and may necessitate additional surveillance in commercial poultry operations in affected regions. Sampling data was simulated using a mechanistic model of H7N9 influenza transmission within commercial poultry barns together with a stochastic observation process. Parameters were estimated using maximum likelihood. We assessed the probability of detecting an outbreak at time of slaughter using both real-time polymerase chain reaction (rt-PCR) and a hemagglutinin inhibition assay (HI assay) before considering more intense sampling prior to slaughter. The day of virus introduction and R0 were estimated jointly from weekly flock sampling data. For scenarios where R0 was known, we estimated the day of virus introduction into a barn under different sampling frequencies. If birds were tested at time of slaughter, there was a higher probability of detecting evidence of an outbreak using an HI assay compared to rt-PCR, except when the virus was introduced <2 weeks before time of slaughter. Prior to the initial detection of infection N sample = 50 (1%) of birds were sampled on a weekly basis once, but after infection was detected, N sample = 2000 birds (40%) were sampled to estimate both parameters. We accurately estimated the day of virus introduction in isolation with weekly and 2-weekly sampling. A strong sampling effort would be required to infer both the day of virus introduction and R0. Such a sampling effort would not be required to estimate the day of virus introduction alone once R0 was known, and sampling N sample = 50 of birds in the flock on a weekly or 2 weekly basis would be sufficient.

"This is not a drill": Activation of a student-led influenza vaccination point of dispensing.

Science.gov (United States)

Adams, Lavonne M; Canclini, Sharon; Tillman, Kelle

2018-04-13

To describe activation of a Point of dispensing (POD) in response to an influenza outbreak, highlighting the use of a student-led model. Faculty, staff, and students of Harris College of Nursing and Health Sciences, Texas Christian University (TCU), as well as those located in its primary building. In response to an August 2017 influenza outbreak, a vaccination clinic was conducted for a target population through POD activation. The larger campus community was served through provision of additional doses by the Texas Christian University Health Center and the annual October student-led vaccination clinic. Eleven additional cases were diagnosed after vaccinations began. One hundred percent of the targeted population was vaccinated (n = 824), with an additional 127 participants vaccinated (others working in the building where POD held also vaccinated). This was the first time POD activation had occurred on campus in response to an outbreak.

Influenza A/H1N1 Severe Pneumonia: Novel Morphocytological Findings in Bronchoalveolar Lavage

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Paola Faverio

2014-01-01

Full Text Available We present the results of bronchoalveolar lavage (BAL performed in three patients with severe influenza A/H1N1 pneumonia complicated by acute respiratory distress syndrome (ARDS. Light microscopy analysis of BAL cytocentrifugates showed the presence of characteristic large, mononuclear, plasmoblastic/plasmocytoid-like cells never described before. Via transmission electron microscopy, these cells were classified as atypical type II pneumocytes and some of them showed cytoplasmic vesicles and inclusions. We concluded that plasmoblastic/plasmocytoid-like type II pneumocytes might represent a morphologic marker of A/H1N1 influenza virus infection as well as reparative cellular activation after diffuse alveolar damage.

Leveraging social networking sites for disease surveillance and public sensing: the case of the 2013 avian influenza A(H7N9 outbreak in China

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Emma Xuxiao Zhang

2015-05-01

Full Text Available We conducted in-depth analysis on the use of a popular Chinese social networking and microblogging site, Sina Weibo, to monitor an avian influenza A(H7N9 outbreak in China and to assess the value of social networking sites in the surveillance of disease outbreaks that occur overseas. Two data sets were employed for our analysis: a line listing of confirmed cases obtained from conventional public health information channels and case information from Weibo posts. Our findings showed that the level of activity on Weibo corresponded with the number of new cases reported. In addition, the reporting of new cases on Weibo was significantly faster than those of conventional reporting sites and non-local news media. A qualitative review of the functions of Weibo also revealed that Weibo enabled timely monitoring of other outbreak-relevant information, provided access to additional crowd-sourced epidemiological information and was leveraged by the local government as an interactive platform for risk communication and monitoring public sentiment on the policy response. Our analysis demonstrated the potential for social networking sites to be used by public health agencies to enhance traditional communicable disease surveillance systems for the global surveillance of overseas public health threats. Social networking sites also can be used by governments for calibration of response policies and measures and for risk communication.

Leveraging social networking sites for disease surveillance and public sensing: the case of the 2013 avian influenza A(H7N9) outbreak in China.

Science.gov (United States)

Zhang, Emma Xuxiao; Yang, Yinping; Di Shang, Richard; Simons, Joseph John Pyne; Quek, Boon Kiat; Yin, Xiao Feng; See, Wanhan; Oh, Olivia Seen Huey; Nandar, Khine Sein Tun; Ling, Vivienne Ruo Yun; Chan, Pei Pei; Wang, Zhaoxia; Goh, Rick Siow Mong; James, Lyn; Tey, Jeannie Su Hui

2015-01-01

We conducted in-depth analysis on the use of a popular Chinese social networking and microblogging site, Sina Weibo, to monitor an avian influenza A(H7N9) outbreak in China and to assess the value of social networking sites in the surveillance of disease outbreaks that occur overseas. Two data sets were employed for our analysis: a line listing of confirmed cases obtained from conventional public health information channels and case information from Weibo posts. Our findings showed that the level of activity on Weibo corresponded with the number of new cases reported. In addition, the reporting of new cases on Weibo was significantly faster than those of conventional reporting sites and non-local news media. A qualitative review of the functions of Weibo also revealed that Weibo enabled timely monitoring of other outbreak-relevant information, provided access to additional crowd-sourced epidemiological information and was leveraged by the local government as an interactive platform for risk communication and monitoring public sentiment on the policy response. Our analysis demonstrated the potential for social networking sites to be used by public health agencies to enhance traditional communicable disease surveillance systems for the global surveillance of overseas public health threats. Social networking sites also can be used by governments for calibration of response policies and measures and for risk communication.

In situ molecular identification of the Influenza A (H1N1 2009 Neuraminidase in patients with severe and fatal infections during a pandemic in Mexico City

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Ocadiz-Delgado Rodolfo

2013-01-01

Full Text Available Abstract Background In April 2009, public health surveillance detected an increased number of influenza-like illnesses in Mexico City’s hospitals. The etiological agent was subsequently determined to be a spread of a worldwide novel influenza A (H1N1 triple reassortant. The purpose of the present study was to demonstrate that molecular detection of pandemic influenza A (H1N1 2009 strains is possible in archival material such as paraffin-embedded lung samples. Methods In order to detect A (H1N1 virus sequences in archived biological samples, eight paraffin-embedded lung samples from patients who died of pneumonia and respiratory failure were tested for influenza A (H1N1 Neuraminidase (NA RNA using in situ RT-PCR. Results We detected NA transcripts in 100% of the previously diagnosed A (H1N1-positive samples as a cytoplasmic signal. No expression was detected by in situ RT-PCR in two Influenza-like Illness A (H1N1-negative patients using standard protocols nor in a non-related cervical cell line. In situ relative transcription levels correlated with those obtained when in vitro RT-PCR assays were performed. Partial sequences of the NA gene from A (H1N1-positive patients were obtained by the in situ RT-PCR-sequencing method. Sequence analysis showed 98% similarity with influenza viruses reported previously in other places. Conclusions We have successfully amplified specific influenza A (H1N1 NA sequences using stored clinical material; results suggest that this strategy could be useful when clinical RNA samples are quantity limited, or when poor quality is obtained. Here, we provide a very sensitive method that specifically detects the neuraminidase viral RNA in lung samples from patients who died from pneumonia caused by Influenza A (H1N1 outbreak in Mexico City.

USGS role and response to highly pathogenic avian influenza

Science.gov (United States)

Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

2015-09-09

Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

Absenteeism in schools during the 2009 influenza A(H1N1) pandemic: a useful tool for early detection of influenza activity in the community?

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Kara, E O; Elliot, A J; Bagnall, H; Foord, D G F; Pnaiser, R; Osman, H; Smith, G E; Olowokure, B

2012-07-01

Certain influenza outbreaks, including the 2009 influenza A(H1N1) pandemic, can predominantly affect school-age children. Therefore the use of school absenteeism data has been considered as a potential tool for providing early warning of increasing influenza activity in the community. This study retrospectively evaluates the usefulness of these data by comparing them with existing syndromic surveillance systems and laboratory data. Weekly mean percentages of absenteeism in 373 state schools (children aged 4-18 years) in Birmingham, UK, from September 2006 to September 2009, were compared with established syndromic surveillance systems including a telephone health helpline, a general practitioner sentinel network and laboratory data for influenza. Correlation coefficients were used to examine the relationship between each syndromic system. In June 2009, school absenteeism generally peaked concomitantly with the existing influenza surveillance systems in England. Weekly school absenteeism surveillance would not have detected pandemic influenza A(H1N1) earlier but daily absenteeism data and the development of baselines could improve the timeliness of the system.

Matrix-M Adjuvated Seasonal Virosomal Influenza Vaccine Induces Partial Protection in Mice and Ferrets against Avian H5 and H7 Challenge.

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Freek Cox

Full Text Available There is a constant threat of zoonotic influenza viruses causing a pandemic outbreak in humans. It is virtually impossible to predict which virus strain will cause the next pandemic and it takes a considerable amount of time before a safe and effective vaccine will be available once a pandemic occurs. In addition, development of pandemic vaccines is hampered by the generally poor immunogenicity of avian influenza viruses in humans. An effective pre-pandemic vaccine is therefore required as a first line of defense. Broadening of the protective efficacy of current seasonal vaccines by adding an adjuvant may be a way to provide such first line of defense. Here we evaluate whether a seasonal trivalent virosomal vaccine (TVV adjuvated with the saponin-based adjuvant Matrix-M (MM can confer protection against avian influenza H5 and H7 virus strains in mice and ferrets. We demonstrate that mice were protected from death against challenges with H5N1 and H7N7, but that the protection was not complete as evidenced by severe clinical signs. In ferrets, protection against H7N9 was not observed. In contrast, reduced upper and lower respiratory tract viral loads and reduced lung pathology, was achieved in H5N1 challenged ferrets. Together these results suggest that, at least to some extent, Matrix-M adjuvated seasonal virosomal influenza vaccine can serve as an interim measure to decrease morbidity and mortality associated with a pandemic outbreak.

Pandemic influenza preparedness: an ethical framework to guide decision-making

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Gibson Jennifer L

2006-12-01

Full Text Available Abstract Background Planning for the next pandemic influenza outbreak is underway in hospitals across the world. The global SARS experience has taught us that ethical frameworks to guide decision-making may help to reduce collateral damage and increase trust and solidarity within and between health care organisations. Good pandemic planning requires reflection on values because science alone cannot tell us how to prepare for a public health crisis. Discussion In this paper, we present an ethical framework for pandemic influenza planning. The ethical framework was developed with expertise from clinical, organisational and public health ethics and validated through a stakeholder engagement process. The ethical framework includes both substantive and procedural elements for ethical pandemic influenza planning. The incorporation of ethics into pandemic planning can be helped by senior hospital administrators sponsoring its use, by having stakeholders vet the framework, and by designing or identifying decision review processes. We discuss the merits and limits of an applied ethical framework for hospital decision-making, as well as the robustness of the framework. Summary The need for reflection on the ethical issues raised by the spectre of a pandemic influenza outbreak is great. Our efforts to address the normative aspects of pandemic planning in hospitals have generated interest from other hospitals and from the governmental sector. The framework will require re-evaluation and refinement and we hope that this paper will generate feedback on how to make it even more robust.

Immune Responses in Acute and Convalescent Patients with Mild, Moderate and Severe Disease during the 2009 Influenza Pandemic in Norway

Science.gov (United States)

Mohn, Kristin G.-I.; Cox, Rebecca Jane; Tunheim, Gro; Berdal, Jan Erik; Hauge, Anna Germundsson; Jul-Larsen, Åsne; Peters, Bjoern; Oftung, Fredrik

2015-01-01

Increased understanding of immune responses influencing clinical severity during pandemic influenza infection is important for improved treatment and vaccine development. In this study we recruited 46 adult patients during the 2009 influenza pandemic and characterized humoral and cellular immune responses. Those included were either acute hospitalized or convalescent patients with different disease severities (mild, moderate or severe). In general, protective antibody responses increased with enhanced disease severity. In the acute patients, we found higher levels of TNF-α single-producing CD4+T-cells in the severely ill as compared to patients with moderate disease. Stimulation of peripheral blood mononuclear cells (PBMC) from a subset of acute patients with peptide T-cell epitopes showed significantly lower frequencies of influenza specific CD8+ compared with CD4+ IFN-γ T-cells in acute patients. Both T-cell subsets were predominantly directed against the envelope antigens (HA and NA). However, in the convalescent patients we found high levels of both CD4+ and CD8+ T-cells directed against conserved core antigens (NP, PA, PB, and M). The results indicate that the antigen targets recognized by the T-cell subsets may vary according to the phase of infection. The apparent low levels of cross-reactive CD8+ T-cells recognizing internal antigens in acute hospitalized patients suggest an important role for this T-cell subset in protective immunity against influenza. PMID:26606759

Use of a Digital Health Application for Influenza Surveillance in China.

Science.gov (United States)

Hswen, Yulin; Brownstein, John S; Liu, Jeremiah; Hawkins, Jared B

2017-07-01

To examine whether a commercial digital health application could support influenza surveillance in China. We retrieved data from the Thermia online and mobile educational tool, which allows parents to monitor their children's fever and infectious febrile illnesses including influenza. We modeled monthly aggregated influenza-like illness case counts from Thermia users over time and compared them against influenza monthly case counts obtained from the National Health and Family Planning Commission of the People's Republic of China by using time series regression analysis. We retrieved 44 999 observations from January 2014 through July 2016 from Thermia China. Thermia appeared to predict influenza outbreaks 1 month earlier than the National Health and Family Planning Commission influenza surveillance system (P = .046). Being younger, not having up-to-date immunizations, and having an underlying health condition were associated with participant-reported influenza-like illness. Digital health applications could supplement traditional influenza surveillance systems in China by providing access to consumers' symptom reporting. Growing popularity and use of commercial digital health applications in China potentially affords opportunities to support disease detection and monitoring and rapid treatment mobilization.

75 FR 10645 - Low Pathogenic Avian Influenza; Voluntary Control Program and Payment of Indemnity

Science.gov (United States)

2010-03-09

... pathogenic avian influenza outbreaks, provides that consistency with humane euthanasia guidelines will be... markets. In the commenter's view, this action would not only provide for disease control but would benefit...

Surveillance for avian influenza viruses in wild birds in Denmark and Greenland

DEFF Research Database (Denmark)

Hjulsager, Charlotte Kristiane; Breum, Solvej Østergaard; Trebbien, Ramona

Avian influenza (AI) is a disease of major threat to poultry production. Surveillance of AI in wild birds contributes to the control of AI. In Denmark (DK) and Greenland (GL), extensive surveillance of AI viruses in the wild bird population has been conducted. The surveillance aimed at detecting......7 subtypes were detected throughout the period together with several other LPAI subtypes. In GL, HPAI was not detected, but few samples were PCR positive for AI. The occurrence of AI subtypes in the wild bird population correlates with concurrent outbreaks of LPAI in Danish poultry, which may...

Estimating the effectiveness of early control measures through school absenteeism surveillance in observed outbreaks at rural schools in Hubei, China.

Science.gov (United States)

Fan, Yunzhou; Yang, Mei; Jiang, Hongbo; Wang, Ying; Yang, Wenwen; Zhang, Zhixia; Yan, Weirong; Diwan, Vinod K; Xu, Biao; Dong, Hengjin; Palm, Lars; Liu, Li; Nie, Shaofa

2014-01-01

School absenteeism is a common data source in syndromic surveillance, which allows for the detection of outbreaks at an early stage. Previous studies focused on its correlation with other data sources. In this study, we evaluated the effectiveness of control measures based on early warning signals from school absenteeism surveillance in rural Chinese schools. A school absenteeism surveillance system was established in all 17 primary schools in 3 adjacent towns in the Chinese region of Hubei. Three outbreaks (varicella, mumps, and influenza-like illness) were detected and controlled successfully from April 1, 2012, to January 15, 2014. An impulse susceptible-exposed-infectious-recovered model was used to fit the epidemics of these three outbreaks. Moreover, it simulated the potential epidemics under interventions resulting from traditional surveillance signals. The effectiveness of the absenteeism-based control measures was evaluated by comparing the simulated datasets. The school absenteeism system generated 52 signals. Three outbreaks were verified through epidemiological investigation. Compared to traditional surveillance, the school absenteeism system generated simultaneous signals for the varicella outbreak, but 3 days in advance for the mumps outbreak and 2-4 days in advance for the influenza-like illness outbreak. The estimated excess protection rates of control measures based on early signals were 0.0%, 19.0-44.1%, and 29.0-37.0% for the three outbreaks, respectively. Although not all outbreak control measures can benefit from early signals through school absenteeism surveillance, the effectiveness of early signal-based interventions is obvious. School absenteeism surveillance plays an important role in reducing outbreak spread.

A national survey of emergency nurses and avian influenza threat.

Science.gov (United States)

Bell, Mary Ann; Dake, Joseph A; Price, James H; Jordan, Timothy R; Rega, Paul

2014-05-01

The purpose of this study was to determine the perceived likelihood of emergency nurses reporting to work during an avian influenza outbreak, to consider options if nurses decided not to report work, and to explore Protection Motivation Theory constructs as predictors of reporting to work. A descriptive, nonexperimental, cross-sectional survey of emergency nurses within the United States. A total of 332 nurses (46%) responded. Most emergency nurses (84%) reported they would report to work (1 in 6 would not). The likelihood of reporting to work differed by education level, nurses' avian influenza information sources, and nurses who had family living with them. Of the nurses who decided not to report to work, the majority were willing to provide health information (90%), administer vaccinations (82%), and triage (74%) neighbors/friends from home. One third of nurses had not attended a disaster-preparedness drill within the past year. Only 20% identified formal training while on the job as a source of avian influenza information. A third of emergency nurses would be worried about getting an avian influenza vaccination because of potential adverse effects. Protection Motivation Theory accounted for almost 40% of the variance of likelihood to report to work, with response costs being the largest predictor. Disaster drills, avian influenza job training, and vaccination education are necessary to prepare emergency nurses for an outbreak. The findings support emergency nurses' willingness to work from home if they are unable to report to work. This finding is new and may have implications for disaster planning, staffing, and ED operations. Copyright © 2014 Emergency Nurses Association. Published by Mosby, Inc. All rights reserved.

Influenza epidemiology and influenza vaccine effectiveness during the 2014–2015 season: annual report from the Global Influenza Hospital Surveillance Network

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Joan Puig-Barberà

2016-08-01

Full Text Available Abstract The Global Influenza Hospital Surveillance Network (GIHSN has established a prospective, active surveillance, hospital-based epidemiological study to collect epidemiological and virological data for the Northern and Southern Hemispheres over several consecutive seasons. It focuses exclusively on severe cases of influenza requiring hospitalization. A standard protocol is shared between sites allowing comparison and pooling of results. During the 2014–2015 influenza season, the GIHSN included seven coordinating sites from six countries (St. Petersburg and Moscow, Russian Federation; Prague, Czech Republic; Istanbul, Turkey; Beijing, China; Valencia, Spain; and Rio de Janeiro, Brazil. Here, we present the detailed epidemiological and influenza vaccine effectiveness findings for the Northern Hemisphere 2014–2015 influenza season.

Severe canine distemper outbreak in unvaccinated dogs in Mozambique

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Julieta Zacarias

2016-07-01

Full Text Available Although significant animal suffering caused by preventable diseases is frequently seen in developing countries, reports of this are scarce. This report describes avoidable animal suffering owing to a suspected canine distemper (CD outbreak in unvaccinated dogs owned by low-income families in Mozambique that killed approximately 200 animals. Affected dogs exhibited clinical signs, and gross and microscopic lesions compatible with CD. Immunohistochemical staining confirmed the presence of canine distemper virus (CDV in the kidney of one dog from the cohort. This brief communication again illustrates that large outbreaks of CDV in unvaccinated dogs occur and that large-scale avoidable suffering and threats to the health of dogs and wild canines continue. Mass vaccination supported by government and non-government organisations is recommended. Keywords: Canine distemper; dogs; outbreak; animal welfare; Mozambique

Addition of αGal HyperAcute™ technology to recombinant avian influenza vaccines induces strong low-dose antibody responses.

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Wenlan Alex Chen

Full Text Available Highly pathogenic avian influenza represents a severe public health threat. Over the last decade, the demand for highly efficacious vaccines against avian influenza viruses has grown, especially after the 2013 H7N9 outbreak in China that resulted in over 600 human cases with over 200 deaths. Currently, there are several H5N1 and H7N9 influenza vaccines in clinical trials, all of which employ traditional oil-in-water adjuvants due to the poor immunogenicity of avian influenza virus antigens. In this study, we developed potent recombinant avian influenza vaccine candidates using HyperAcute™ Technology, which takes advantage of naturally-acquired anti-αGal immunity in humans. We successfully generated αGal-positive recombinant protein and virus-like particle vaccine candidates of H5N1 and H7N9 influenza strains using either biological or our novel CarboLink chemical αGal modification techniques. Strikingly, two doses of 100 ng αGal-modified vaccine, with no traditional adjuvant, was able to induce a much stronger humoral response in αGT BALB/c knockout mice (the only experimental system readily available for testing αGal in vivo than unmodified vaccines even at 10-fold higher dose (1000 ng/dose. Our data strongly suggest that αGal modification significantly enhances the humoral immunogenicity of the recombinant influenza vaccine candidates. Use of αGal HyperAcute™ technology allows significant dose-sparing while retaining desired immunogenicity. Our success in the development of highly potent H5N1 and H7N9 vaccine candidates demonstrated the potential of αGal HyperAcute™ technology for the development of vaccines against other infectious diseases.

Seasonal Influenza A H1N1pdm09 Virus and Severe Outcomes: A Reason for Broader Vaccination in Non-Elderly, At-Risk People.

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Elisa Minchole

Full Text Available Recent pandemics of influenza A H1N1pdm09 virus have caused severe illness, especially in young people. Very few studies on influenza A H1N1pdm09 in post-pandemic periods exist, and there is no information on the severity of both seasonal influenza A(H1N1 and A(H3N2 from the same season, adjusting for potential confounders, including vaccine.We performed a retrospective observational study of adults hospitalized during the 2014 season with influenza A(H1N1 or A(H3N2. All patients underwent the same diagnostic and therapeutic protocol in a single hospital, including early Oseltamivir therapy. We included 234 patients: 146 (62.4% influenza A(H1N1 and 88 (37.6% A(H3N2. A(H1N1 patients were younger (p<0.01, developed more pneumonia (p<0.01, respiratory complications (p = 0.015, ARDS (p = 0.047, and septic shock (p = 0.049, were more frequently admitted to the ICU (p = 0.022, required IMV (p = 0.049, and were less frequently vaccinated (p = 0.008. After adjusting for age, comorbidities, time from onset of illness, and vaccine status, influenza A(H1N1 (OR, 2.525, coinfection (OR, 2.821, and no vaccination (OR, 3.086 were independent risk factors for severe disease.Hospitalized patients with influenza A(H1N1 were more than twice as likely to have severe influenza. They were younger and most had not received the vaccine. Our findings suggest that seasonal influenza A(H1N1 maintains some features of pandemic viruses, and recommend wider use of vaccination in younger adult high-risk patients.

[Analysis of risk factors of fatal outcome in pregnant and puerperant patients with severe H1N1 influenza].

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Zabolotskikh, I B; Penzhoian, G A; Musaeva, T S; Goncharenko, S I

2010-01-01

As well as previous epidemics and pandemias of influenza, the 2009 H1N1 influenza pandemia increases the risk of severe illness in pregnant. Data were reported for 28 pregnant and 2 postpartum women who have been hospitalized in ICUs of Krasnodar Region with H1N1 influenza diagnosis. The laboratory tests for H1N1 were negative in 53.3% of suspected cases of H1N1 influenza (16 of 30). The major lethal risk factor in pregnant with H1N1 influenza is a development of septic shock with low PaO2\\FiO2 ratio (less than 140) and high Murray's Acute Lung Injury Score (higher than 2.5). High Apache II, Apache III, SAPS 2, SAPS 3 and SOFA scores are the additional lethal risk factors. Lethal outcomes were more frequent in the end of the second trimester of pregnancy.

Using Google Trends for influenza surveillance in South China.

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Kang, Min; Zhong, Haojie; He, Jianfeng; Rutherford, Shannon; Yang, Fen

2013-01-01

Google Flu Trends was developed to estimate influenza activity in many countries; however there is currently no Google Flu Trends or other Internet search data used for influenza surveillance in China. Influenza surveillance data from 2008 through 2011 were obtained from provincial CDC influenza-like illness and virological surveillance systems of Guangdong, a province in south China. Internet search data were downloaded from the website of Google Trends. Pearson's correlation coefficients with 95% confidence intervals (95% CI) were calculated to compare surveillance data and internet search trends. The correlation between CDC ILI surveillance and CDC virus surveillance was 0.56 (95% CI: 0.43, 0.66). The strongest correlation was between the Google Trends term of Fever and ILI surveillance with a correlation coefficient of 0.73 (95% CI: 0.66, 0.79). When compared with influenza virological surveillance, the Google Trends term of Influenza A had the strongest correlation with a correlation coefficient of 0.64 (95% CI: 0.43, 0.79) in the 2009 H1N1 influenza pandemic period. This study shows that Google Trends in Chinese can be used as a complementary source of data for influenza surveillance in south China. More research in the future should develop new models using search trends in Chinese language to estimate local disease activity and detect early signals of outbreaks.

The cost effectiveness of pandemic influenza interventions: a pandemic severity based analysis.

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George J Milne

Full Text Available BACKGROUND: The impact of a newly emerged influenza pandemic will depend on its transmissibility and severity. Understanding how these pandemic features impact on the effectiveness and cost effectiveness of alternative intervention strategies is important for pandemic planning. METHODS: A cost effectiveness analysis of a comprehensive range of social distancing and antiviral drug strategies intended to mitigate a future pandemic was conducted using a simulation model of a community of ∼30,000 in Australia. Six pandemic severity categories were defined based on case fatality ratio (CFR, using data from the 2009/2010 pandemic to relate hospitalisation rates to CFR. RESULTS: Intervention strategies combining school closure with antiviral treatment and prophylaxis are the most cost effective strategies in terms of cost per life year saved (LYS for all severity categories. The cost component in the cost per LYS ratio varies depending on pandemic severity: for a severe pandemic (CFR of 2.5% the cost is ∼$9 k per LYS; for a low severity pandemic (CFR of 0.1% this strategy costs ∼$58 k per LYS; for a pandemic with very low severity similar to the 2009 pandemic (CFR of 0.03% the cost is ∼$155 per LYS. With high severity pandemics (CFR >0.75% the most effective attack rate reduction strategies are also the most cost effective. During low severity pandemics costs are dominated by productivity losses due to illness and social distancing interventions, while for high severity pandemics costs are dominated by hospitalisation costs and productivity losses due to death. CONCLUSIONS: The most cost effective strategies for mitigating an influenza pandemic involve combining sustained social distancing with the use of antiviral agents. For low severity pandemics the most cost effective strategies involve antiviral treatment, prophylaxis and short durations of school closure; while these are cost effective they are less effective than other strategies in

The Cost Effectiveness of Pandemic Influenza Interventions: A Pandemic Severity Based Analysis

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Milne, George J.; Halder, Nilimesh; Kelso, Joel K.

2013-01-01

Background The impact of a newly emerged influenza pandemic will depend on its transmissibility and severity. Understanding how these pandemic features impact on the effectiveness and cost effectiveness of alternative intervention strategies is important for pandemic planning. Methods A cost effectiveness analysis of a comprehensive range of social distancing and antiviral drug strategies intended to mitigate a future pandemic was conducted using a simulation model of a community of ∼30,000 in Australia. Six pandemic severity categories were defined based on case fatality ratio (CFR), using data from the 2009/2010 pandemic to relate hospitalisation rates to CFR. Results Intervention strategies combining school closure with antiviral treatment and prophylaxis are the most cost effective strategies in terms of cost per life year saved (LYS) for all severity categories. The cost component in the cost per LYS ratio varies depending on pandemic severity: for a severe pandemic (CFR of 2.5%) the cost is ∼$9 k per LYS; for a low severity pandemic (CFR of 0.1%) this strategy costs ∼$58 k per LYS; for a pandemic with very low severity similar to the 2009 pandemic (CFR of 0.03%) the cost is ∼$155 per LYS. With high severity pandemics (CFR >0.75%) the most effective attack rate reduction strategies are also the most cost effective. During low severity pandemics costs are dominated by productivity losses due to illness and social distancing interventions, while for high severity pandemics costs are dominated by hospitalisation costs and productivity losses due to death. Conclusions The most cost effective strategies for mitigating an influenza pandemic involve combining sustained social distancing with the use of antiviral agents. For low severity pandemics the most cost effective strategies involve antiviral treatment, prophylaxis and short durations of school closure; while these are cost effective they are less effective than other strategies in reducing the

Cold And Flu: Conventional vs Botanical & Nutritional Therapy

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KALRA M; KHATAK M; KHATAK S

2011-01-01

Cold and flu (or Influenza) are both respiratory illnesses and the terms are used interchangeably. However, they are both caused by different viruses. There are two main types of flu viruses: influenza A and influenza B. The most serious and deadly flu outbreaks are caused by influenza A because of its ability to genetically shift into new forms against which no person has developed immunity. Influenza B generally causes less severe infection. Outbreaks of influenza B commonly occur in school...

Mechanical ventilation in patients with most severe forms of influenza a H1N1

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Romić Predrag

2011-01-01

Full Text Available Background/Aim. Pandemic of A H1N1 influenza is noted for its rapid spreading and life-threatening consequences like acute respiratory distress syndrome (ARDS which requires mechanical ventilation (MV and intensive therapy (IT. The aim of the study was to determine the significance of mechanical ventilation application in the presence of comorbidities on the outcome of the disease and patients with severe forms of acute influenza caused by A H1N1 virus. Methods. Five patients with acute respiratory failure caused by A H1N1 influenza that required MV were included in the study. Course and outcome of the treatment were monitored in relation to age and sex of the patients, concomitant diseases, time of influenza beginning, a time of admittance in an intensive care unit, a time of an endotracheal intubation and MV beginning, MV duration and occurrence of secondary infections. Results. Three patients were on a very prolonged MV (39, 43 and 20 days, respectively and they all survived. Two patients with a significantly shorter duration of MV (14 and 12 days, respectively died because of a very severe clinical course and concomitant diseases. Unexpectedly, we found a positive correlation between duration of MV and survival although two patients, who were on MV for the longest period of time (43 and 39 days, respectively, developed, as a complication, secondary bacterial pneumonia. Conclusion. Intensive therapy of patients with ARDS due to A H1N1 influenza virus requires MV which should be carried out according to guidelines of international expert forums. That is in accordance with our unexpected observation on negative correlation between duration of MV and fatal outcome. Intensive treatment of these patients, specially MV, can be very prolonged and, therefore, requires specialized teams of anesthesiologists, separate, isolated intensive therapy units and high level of medical staff protection, as was the case in this study, so no member of medical

Knowledge, motivation, and attitudes of Hungarian family physicians toward pandemic influenza vaccination in the 2009/10 influenza season: questionnaire study.

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Rurik, Imre; Langmár, Zoltán; Márton, Hajnalka; Kovács, Eszter; Szigethy, Endre; Ilyés, István

2011-04-15

To evaluate the knowledge, motivation, and attitudes of Hungarian family physicians toward pandemic influenza vaccination in the 2009/10 influenza season. A questionnaire with 20 questions was developed and sent to 232 family physicians in 3 largest Hungarian cities: Budapest, Debrecen, and Miskolc. The study was conducted in December 2009 and January 2010. A hundred and ninety eight (85%) physicians answered the questionnaire adequately. Respondents believed that the influenza outbreak represented less of a threat to their practices than to Hungary or the world as a whole. They mostly agreed that vaccination was important and were frequently dissatisfied with the support from health authorities. The proportion of vaccinated patients ranged between 2% and 53%, without differences according to geographical region, age, sex, and duration of physicians' employment in family practice. Physicians who were satisfied with the payment for procedures and underwent vaccination themselves were more active in vaccination. Health authorities should provide clear and evidence-based professional support to family physicians and should encourage them to get vaccinated against pandemic influenza, while insurance funds have to establish appropriate reimbursement system.

A retrospective analysis of oral cholera vaccine use, disease severity and deaths during an outbreak in South Sudan.

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Bekolo, Cavin Epie; van Loenhout, Joris Adriaan Frank; Rodriguez-Llanes, Jose Manuel; Rumunu, John; Ramadan, Otim Patrick; Guha-Sapir, Debarati

2016-09-01

To determine whether pre-emptive oral cholera vaccination reduces disease severity and mortality in people who develop cholera disease during an outbreak. The study involved a retrospective analysis of demographic and clinical data from 41 cholera treatment facilities in South Sudan on patients who developed cholera disease between 23 April and 20 July 2014 during a large outbreak, a few months after a pre-emptive oral vaccination campaign. Patients who developed severe dehydration were regarded as having a severe cholera infection. Vaccinated and unvaccinated patients were compared and multivariate logistic regression analysis was used to identify factors associated with developing severe disease or death. In total, 4115 cholera patients were treated at the 41 facilities: 1946 (47.3%) had severe disease and 62 (1.5%) deaths occurred. Multivariate analysis showed that patients who received two doses of oral cholera vaccine were 4.5-fold less likely to develop severe disease than unvaccinated patients (adjusted odds ratio, aOR: 0.22; 95% confidence interval, CI: 0.11-0.44). Moreover, those with severe cholera were significantly more likely to die than those without (aOR: 4.76; 95% CI: 2.33-9.77). Pre-emptive vaccination with two doses of oral cholera vaccine was associated with a significant reduction in the likelihood of developing severe cholera disease during an outbreak in South Sudan. Moreover, severe disease was the strongest predictor of death. Two doses of oral cholera vaccine should be used in emergencies to reduce the disease burden.

Strengthening the diagnostic capacity to detect Bio Safety Level 3 organisms in unusual respiratory viral outbreaks.

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van Asten, Liselotte; van der Lubben, Mariken; van den Wijngaard, Cees; van Pelt, Wilfrid; Verheij, Robert; Jacobi, Andre; Overduin, Pieter; Meijer, Adam; Luijt, Dirk; Claas, Eric; Hermans, Mirjam; Melchers, Willem; Rossen, John; Schuurman, Rob; Wolffs, Petra; Boucher, Charles; Bouchier, Charles; Schirm, Jurjen; Kroes, Louis; Leenders, Sander; Galama, Joep; Peeters, Marcel; van Loon, Anton; Stobberingh, Ellen; Schutten, Martin; Koopmans, Marion

2009-07-01

Experience with a highly pathogenic avian influenza outbreak in the Netherlands (2003) illustrated that the diagnostic demand for respiratory viruses at different biosafety levels (including BSL3), can increase unexpectedly and dramatically. We describe the measures taken since, aimed at strengthening national laboratory surge capacity and improving preparedness for dealing with diagnostic demand during outbreaks of (emerging) respiratory virus infections, including pandemic influenza virus. Academic and peripheral medical-microbiological laboratories collaborated to determine minimal laboratory requirements for the identification of viruses in the early stages of a pandemic or a large outbreak of avian influenza virus. Next, an enhanced collaborative national network of outbreak assistance laboratories (OAL) was set up. An inventory was made of the maximum diagnostic throughput that this network can deliver in a period of intensified demand. For an estimate of the potential magnitude of this surge demand, historical counts were calculated from hospital- and physician-based registries of patients presenting with respiratory symptoms. Number of respiratory physician-visits ranged from 140,000 to 615,000 per month and hospitalizations ranged from 3000 to 11,500 per month. The established OAL-network provides rapid diagnostic response with agreed quality requirements and a maximum throughput capacity of 1275 samples/day (38,000 per month), assuming other routine diagnostic work needs to be maintained. Thus surge demand for diagnostics for hospitalized cases (if not distinguishable from other respiratory illness) could be handled by the OAL network. Assessing etiology of community acquired acute respiratory infection however, may rapidly exceed the capacity of the network. Therefore algorithms are needed for triaging for laboratory diagnostics; currently this is not addressed in pandemic preparedness plans.

Identification of TMPRSS2 as a Susceptibility Gene for Severe 2009 Pandemic A(H1N1) Influenza and A(H7N9) Influenza

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Cheng, Zhongshan; Zhou, Jie; To, Kelvin Kai-Wang; Chu, Hin; Li, Cun; Wang, Dong; Yang, Dong; Zheng, Shufa; Hao, Ke; Bosse, Yohan; Obeidat, Ma'en; Brandsma, Corry-Anke; Song, You-Qiang; Chen, Yu; Zheng, Bo-Jian; Li, Lanjuan; Yuen, Kwok-Yung

2015-01-01

The genetic predisposition to severe A(H1N1) 2009 (A[H1N1]pdm09) influenza was evaluated in 409 patients, including 162 cases with severe infection and 247 controls with mild infection. We prioritized candidate variants based on the result of a pilot genome-wide association study and a lung

Novel pandemic influenza A(H1N1 viruses are potently inhibited by DAS181, a sialidase fusion protein.

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Gallen B Triana-Baltzer

2009-11-01

Full Text Available The recent emergence of a novel pandemic influenza A(H1N1 strain in humans exemplifies the rapid and unpredictable nature of influenza virus evolution and the need for effective therapeutics and vaccines to control such outbreaks. However, resistance to antivirals can be a formidable problem as evidenced by the currently widespread oseltamivir- and adamantane-resistant seasonal influenza A viruses (IFV. Additional antiviral approaches with novel mechanisms of action are needed to combat novel and resistant influenza strains. DAS181 (Fludase is a sialidase fusion protein in early clinical development with in vitro and in vivo preclinical activity against a variety of seasonal influenza strains and highly pathogenic avian influenza strains (A/H5N1. Here, we use in vitro, ex vivo, and in vivo models to evaluate the activity of DAS181 against several pandemic influenza A(H1N1 viruses.The activity of DAS181 against several pandemic influenza A(H1N1 virus isolates was examined in MDCK cells, differentiated primary human respiratory tract culture, ex-vivo human bronchi tissue and mice. DAS181 efficiently inhibited viral replication in each of these models and against all tested pandemic influenza A(H1N1 strains. DAS181 treatment also protected mice from pandemic influenza A(H1N1-induced pathogenesis. Furthermore, DAS181 antiviral activity against pandemic influenza A(H1N1 strains was comparable to that observed against seasonal influenza virus including the H274Y oseltamivir-resistant influenza virus.The sialidase fusion protein DAS181 exhibits potent inhibitory activity against pandemic influenza A(H1N1 viruses. As inhibition was also observed with oseltamivir-resistant IFV (H274Y, DAS181 may be active against the antigenically novel pandemic influenza A(H1N1 virus should it acquire the H274Y mutation. Based on these and previous results demonstrating DAS181 broad-spectrum anti-IFV activity, DAS181 represents a potential therapeutic agent for

Cloning and Expression of Recombinant Nucleoprotein of Influenza H1N1

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Somaie Tavakoli

2015-04-01

Full Text Available Background: Influenza virus is the major cause of lower respiratory tract illnesses on the worldwide. Vaccination can be an effective tool to prevent its outbreak. Highly conserved viral nucleoprotein is an effective vaccine candidate to provide heterosubtypic immunity, offering resistance against various influenza virus strains.Materials and Methods: In present research NP gene was inserted in pET-22b expression vector. New construct (pET-22b/NP was transformed into E. coli BL21 (DE3 strain and the expression of nucleoprotein was induced by IPTG. It was analyzed by SDS-PAGE and confirmed by Western blotting.Results: Western blotting confirmed the expression and production of recombinant Influenza nucleoprotein.Conclusion: These results suggest that the codon-optimized influenza A virus NP gene can be efficiently expressed in E. coli.

Outbreaks of emerging infectious diseases: Risk perception and behaviour of the general public

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M. Bults (Marloes)

2014-01-01

markdownabstract__Abstract__ This thesis focuses on risk perception and behaviour of the public during the outbreaks of emerging infectious diseases. It consists of studies on Influenza A (H1N1), Q fever and Lyme disease. These studies were conducted among both the general public and specific

Immunity to current H5 highly pathogenic avian influenza viruses: From vaccines to adaptive immunity in wild birds

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Following the 2014-2015 outbreaks of H5N2 and H5N8 highly pathogenic avian influenza (HPAI) in the U.S., studies were performed to assess the immunity required for protection against future outbreaks should they occur. We assessed the ability of vaccines to induce protection of chickens and turkeys...

Pathogenesis, Transmissibility, and Tropism of a Highly Pathogenic Avian Influenza A(H7N7) Virus Associated With Human Conjunctivitis in Italy, 2013.

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Belser, Jessica A; Creager, Hannah M; Zeng, Hui; Maines, Taronna R; Tumpey, Terrence M

2017-09-15

H7 subtype influenza viruses represent a persistent public health threat because of their continued detection in poultry and ability to cause human infection. An outbreak of highly pathogenic avian influenza H7N7 virus in Italy during 2013 resulted in 3 cases of human conjunctivitis. We determined the pathogenicity and transmissibility of influenza A/Italy/3/2013 virus in mouse and ferret models and examined the replication kinetics of this virus in several human epithelial cell types. The moderate virulence observed in mammalian models and the capacity for transmission in a direct contact model underscore the need for continued study of H7 subtype viruses. Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Effects of closing and reopening live poultry markets on the epidemic of human infection with avian influenza A virus

OpenAIRE

Lu, Jian; Liu, Wendong; Xia, Rui; Dai, Qigang; Bao, Changjun; Tang, Fenyang; Zhu, yefei; Wang, Qiao

2015-01-01

Abstract Live poultry markets (LPMs) are crucial places for human infection of influenza A (H7N9 virus). In Yangtze River Delta, LPMs were closed after the outbreak of human infection with avian influenza A (H7N9) virus, and then reopened when no case was found. Our purpose was to quantify the effect of LPMs? operations in this region on the transmission of influenza A (H7N9) virus. We obtained information about dates of symptom onset and locations for all human influenza A (H7N9) cases repor...

Highly Pathogenic Avian Influenza Virus among Wild Birds in Mongolia

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Gilbert, Martin; Jambal, Losolmaa; Karesh, William B.; Fine, Amanda; Shiilegdamba, Enkhtuvshin; Dulam, Purevtseren; Sodnomdarjaa, Ruuragchaa; Ganzorig, Khuukhenbaatar; Batchuluun, Damdinjav; Tseveenmyadag, Natsagdorj; Bolortuya, Purevsuren; Cardona, Carol J.; Leung, Connie Y. H.; Peiris, J. S. Malik; Spackman, Erica; Swayne, David E.; Joly, Damien O.

2012-01-01

Mongolia combines a near absence of domestic poultry, with an abundance of migratory waterbirds, to create an ideal location to study the epidemiology of highly pathogenic avian influenza virus (HPAIV) in a purely wild bird system. Here we present the findings of active and passive surveillance for HPAIV subtype H5N1 in Mongolia from 2005–2011, together with the results of five outbreak investigations. In total eight HPAIV outbreaks were confirmed in Mongolia during this period. Of these, one was detected during active surveillance employed by this project, three by active surveillance performed by Mongolian government agencies, and four through passive surveillance. A further three outbreaks were recorded in the neighbouring Tyva Republic of Russia on a lake that bisects the international border. No HPAIV was isolated (cultured) from 7,855 environmental fecal samples (primarily from ducks), or from 2,765 live, clinically healthy birds captured during active surveillance (primarily shelducks, geese and swans), while four HPAIVs were isolated from 141 clinically ill or dead birds located through active surveillance. Two low pathogenic avian influenza viruses (LPAIV) were cultured from ill or dead birds during active surveillance, while environmental feces and live healthy birds yielded 56 and 1 LPAIV respectively. All Mongolian outbreaks occurred in 2005 and 2006 (clade 2.2), or 2009 and 2010 (clade 2.3.2.1); all years in which spring HPAIV outbreaks were reported in Tibet and/or Qinghai provinces in China. The occurrence of outbreaks in areas deficient in domestic poultry is strong evidence that wild birds can carry HPAIV over at least moderate distances. However, failure to detect further outbreaks of clade 2.2 after June 2006, and clade 2.3.2.1 after June 2010 suggests that wild birds migrating to and from Mongolia may not be competent as indefinite reservoirs of HPAIV, or that HPAIV did not reach susceptible populations during our study. PMID:22984464

Influenza forecasting with Google Flu Trends.

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Dugas, Andrea Freyer; Jalalpour, Mehdi; Gel, Yulia; Levin, Scott; Torcaso, Fred; Igusa, Takeru; Rothman, Richard E

2013-01-01

We developed a practical influenza forecast model based on real-time, geographically focused, and easy to access data, designed to provide individual medical centers with advanced warning of the expected number of influenza cases, thus allowing for sufficient time to implement interventions. Secondly, we evaluated the effects of incorporating a real-time influenza surveillance system, Google Flu Trends, and meteorological and temporal information on forecast accuracy. Forecast models designed to predict one week in advance were developed from weekly counts of confirmed influenza cases over seven seasons (2004-2011) divided into seven training and out-of-sample verification sets. Forecasting procedures using classical Box-Jenkins, generalized linear models (GLM), and generalized linear autoregressive moving average (GARMA) methods were employed to develop the final model and assess the relative contribution of external variables such as, Google Flu Trends, meteorological data, and temporal information. A GARMA(3,0) forecast model with Negative Binomial distribution integrating Google Flu Trends information provided the most accurate influenza case predictions. The model, on the average, predicts weekly influenza cases during 7 out-of-sample outbreaks within 7 cases for 83% of estimates. Google Flu Trend data was the only source of external information to provide statistically significant forecast improvements over the base model in four of the seven out-of-sample verification sets. Overall, the p-value of adding this external information to the model is 0.0005. The other exogenous variables did not yield a statistically significant improvement in any of the verification sets. Integer-valued autoregression of influenza cases provides a strong base forecast model, which is enhanced by the addition of Google Flu Trends confirming the predictive capabilities of search query based syndromic surveillance. This accessible and flexible forecast model can be used by

Influenza Transmission in the Mother-Infant Dyad Leads to Severe Disease, Mammary Gland Infection, and Pathogenesis by Regulating Host Responses.

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Paquette, Stéphane G; Banner, David; Huang, Stephen S H; Almansa, Raquel; Leon, Alberto; Xu, Luoling; Bartoszko, Jessica; Kelvin, David J; Kelvin, Alyson A

2015-10-01

Seasonal influenza viruses are typically restricted to the human upper respiratory tract whereas influenza viruses with greater pathogenic potential often also target extra-pulmonary organs. Infants, pregnant women, and breastfeeding mothers are highly susceptible to severe respiratory disease following influenza virus infection but the mechanisms of disease severity in the mother-infant dyad are poorly understood. Here we investigated 2009 H1N1 influenza virus infection and transmission in breastfeeding mothers and infants utilizing our developed infant-mother ferret influenza model. Infants acquired severe disease and mortality following infection. Transmission of the virus from infants to mother ferrets led to infection in the lungs and mother mortality. Live virus was also found in mammary gland tissue and expressed milk of the mothers which eventually led to milk cessation. Histopathology showed destruction of acini glandular architecture with the absence of milk. The virus was localized in mammary epithelial cells of positive glands. To understand the molecular mechanisms of mammary gland infection, we performed global transcript analysis which showed downregulation of milk production genes such as Prolactin and increased breast involution pathways indicated by a STAT5 to STAT3 signaling shift. Genes associated with cancer development were also significantly increased including JUN, FOS and M2 macrophage markers. Immune responses within the mammary gland were characterized by decreased lymphocyte-associated genes CD3e, IL2Ra, CD4 with IL1β upregulation. Direct inoculation of H1N1 into the mammary gland led to infant respiratory infection and infant mortality suggesting the influenza virus was able to replicate in mammary tissue and transmission is possible through breastfeeding. In vitro infection studies with human breast cells showed susceptibility to H1N1 virus infection. Together, we have shown that the host-pathogen interactions of influenza virus

SNPer: an R library for quantitative variant analysis on single nucleotide polymorphisms among influenza virus populations.

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Unitsa Sangket

Full Text Available Influenza virus (IFV can evolve rapidly leading to genetic drifts and shifts resulting in human and animal influenza epidemics and pandemics. The genetic shift that gave rise to the 2009 influenza A/H1N1 pandemic originated from a triple gene reassortment of avian, swine and human IFVs. More minor genetic alterations in genetic drift can lead to influenza drug resistance such as the H274Y mutation associated with oseltamivir resistance. Hence, a rapid tool to detect IFV mutations and the potential emergence of new virulent strains can better prepare us for seasonal influenza outbreaks as well as potential pandemics. Furthermore, identification of specific mutations by closely examining single nucleotide polymorphisms (SNPs in IFV sequences is essential to classify potential genetic markers associated with potentially dangerous IFV phenotypes. In this study, we developed a novel R library called "SNPer" to analyze quantitative variants in SNPs among IFV subpopulations. The computational SNPer program was applied to three different subpopulations of published IFV genomic information. SNPer queried SNPs data and grouped the SNPs into (1 universal SNPs, (2 likely common SNPs, and (3 unique SNPs. SNPer outperformed manual visualization in terms of time and labor. SNPer took only three seconds with no errors in SNP comparison events compared with 40 hours with errors using manual visualization. The SNPer tool can accelerate the capacity to capture new and potentially dangerous IFV strains to mitigate future influenza outbreaks.

Transmission of Influenza A Viruses

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Neumann, Gabriele; Kawaoka, Yoshihiro

2015-01-01

Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

Is the association between hip fractures and seasonality modified by influenza vaccination? An ecological study.

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Fraenkel, M; Yitshak-Sade, M; Beacher, L; Carmeli, M; Mandelboim, M; Siris, E; Novack, V

2017-09-01

Osteoporotic hip fractures in 4344 patients were more common during winter. Lower temperatures were associated with higher rates of fracture only in those not vaccinated for influenza. Influenza outbreaks increased the risk of hip fractures. Further studies are needed to assess whether influenza vaccination can prevent hip fractures. Winter seasonality of osteoporotic hip fracture incidence has been demonstrated, yet the explanation for the association is lacking. We hypothesize that the seasonality of osteoporotic hip fracture can be explained by an association between hip fractures and seasonal influenza outbreaks. This retrospective cohort study included all patients admitted to Soroka University Medical Center with a diagnosis of osteoporotic hip fracture (ICD-9 code 820) between the years 2001 and 2013. Patients with malignancies, trauma, and age under 50 were excluded. In a time series analysis, we examined the association between hip fracture incidence and seasonality adjusted for meteorological factors, and population rates of influenza infection and vaccination using Poisson models. Four thousand three hundred forty-four patients with a hip fracture were included (69% females, mean age 78). Daily fracture rates were significantly higher in winter (1.1 fractures/day) compared to summer, fall, and spring (0.79, 0.90, and 0.91; p risk only in those not vaccinated for influenza (n = 2939, for every decrease of 5 °C, RR 1.08, CI 1.02-1.16; p risk for hip fracture, adjusted for seasons and temperature, was 1.26 2 weeks following a week with high infection burden (CI 1.05;1.51 p = 0.01), while the temperature was not significantly associated with the fracture risk. Under dry and warm desert climate, winter hip fracture incidence increase might be associated with influenza infection, and this effect can be negated by influenza vaccination.

Agro-Environmental Determinants of Avian Influenza Circulation: A Multisite Study in Thailand, Vietnam and Madagascar

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Paul, Mathilde C.; Gilbert, Marius; Desvaux, Stéphanie; Rasamoelina Andriamanivo, Harena; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Véronique

2014-01-01

Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 2004–2005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced. PMID:25029441

Influence of time to diagnosis of severe influenza on antibiotic use, length of stay, isolation precautions, and mortality: a retrospective study.

Science.gov (United States)

Akers, Isabel E; Weber, Rainer; Sax, Hugo; Böni, Jürg; Trkola, Alexandra; Kuster, Stefan P

2017-07-01

Timely diagnosis of influenza infection in patients might help reduce antibiotic use during influenza seasons and, consequently, antibiotic selection pressure. In this retrospective cohort study, we aimed to evaluate whether time to influenza diagnosis in patients with severe influenza is associated with the duration of antibiotic therapy. We retrospectively included all hospitalized patients >16 years who tested positive for influenza A or B by polymerase chain reaction during influenza seasons 2013/2014 or 2014/2015 at the University Hospital Zurich. The primary aim was to assess the association between timing of laboratory-confirmed influenza diagnosis and duration of antibiotic therapy. Secondary outcomes were length of hospital stay, duration of isolation precautions, and mortality. Early diagnosis was defined as laboratory confirmation on the day of or the day after hospital admission or symptom onset. A total of 126 patients were included (median age 57 years). Timing of influenza diagnosis was not associated with the duration of antibiotic treatment, the duration of isolation precautions, or mortality. Early influenza was associated with reduced length of hospital stay (median 7 vs 9 days [P=.014]) in patients with community-acquired influenza. Although the duration of antibiotic therapy and mortality were found unaffected by early influenza diagnosis, our data indicate that it is linked with a reduction in the length of hospitalization in patients with community-acquired influenza. This highlights a need to also fully understand the effect of time to diagnosis of bacterial pathogens on antibiotic prescribing patterns in order to exploit the potential of early influenza diagnosis in patient care. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Duration of immunity induced by an equine influenza and tetanus combination vaccine formulation adjuvanted with ISCOM-Matrix.

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Heldens, J G M; Pouwels, H G W; Derks, C G G; Van de Zande, S M A; Hoeijmakers, M J H

2010-10-08

Equine influenza is a contagious disease caused by equine influenza virus which belongs to the orthomyxovirus family. Outbreaks of equine influenza cause severe economic loses to the horse industry and consequently horses in competition are required to be regularly vaccinated against equine influenza. Unlike the existing inactivated vaccines, Equilis Prequenza Te is the only one able to induce protection against clinical disease and virus excretion after a primary vaccination course consisting of two vaccine applications 4-6 weeks apart until the recommended time of the third vaccination. In this paper we describe the duration of immunity profile, tested in an experimental setting according to European legislation, of this inactivated equine influenza and tetanus combination vaccine. In addition to influenza antigen, the formulation contains a second generation ISCOM (the so called ISCOMatrix) as an adjuvant. The vaccine aims at the induction of protection from the primary vaccination course until the time of annual revaccination 12 months later, against challenge with a virulent equine influenza strain. The protection against A/equine/Kentucky/95 (H3N8) at the time of annual revaccination was evidenced by a significant reduction of clinical signs of influenza, a significant reduction of virus excretion and a significant reduction of fever. The effect of the annual revaccination on the duration of immunity against influenza and tetanus was also studied by serology. For tetanus, as a consequence of the 24 months duration of immunity, an alternating annual vaccination schedule consisting of Prequenza and Prequenza Te is proposed after the first three doses of Prequenza Te. Copyright © 2010 Elsevier Ltd. All rights reserved.

Avian Influenza Biosecurity: Filling the Gaps with Non-Traditional Education

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Madsen, Jennifer; Tablante, Nathaniel

2013-01-01

Outbreaks of highly pathogenic avian influenza have become endemic, crippling trade and livelihood for many, and in rare cases, resulting in human fatalities. It is imperative that up-to-date education and training in accessible and interactive formats be available to key target audiences like poultry producers, backyard flock owners, and…

Contemporary avian influenza A virus subtype H1, H6, H7, H10, and H15 hemagglutinin genes encode a mammalian virulence factor similar to the 1918 pandemic virus H1 hemagglutinin.

Science.gov (United States)

Qi, Li; Pujanauski, Lindsey M; Davis, A Sally; Schwartzman, Louis M; Chertow, Daniel S; Baxter, David; Scherler, Kelsey; Hartshorn, Kevan L; Slemons, Richard D; Walters, Kathie-Anne; Kash, John C; Taubenberger, Jeffery K

2014-11-18

Zoonotic avian influenza virus infections may lead to epidemics or pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its H1 hemagglutinin was identified as a key mammalian virulence factor. A chimeric 1918 virus expressing a contemporary avian H1 hemagglutinin, however, displayed murine pathogenicity indistinguishable from that of the 1918 virus. Here, isogenic chimeric avian influenza viruses were constructed on an avian influenza virus backbone, differing only by hemagglutinin subtype expressed. Viruses expressing the avian H1, H6, H7, H10, and H15 subtypes were pathogenic in mice and cytopathic in normal human bronchial epithelial cells, in contrast to H2-, H3-, H5-, H9-, H11-, H13-, H14-, and H16-expressing viruses. Mouse pathogenicity was associated with pulmonary macrophage and neutrophil recruitment. These data suggest that avian influenza virus hemagglutinins H1, H6, H7, H10, and H15 contain inherent mammalian virulence factors and likely share a key virulence property of the 1918 virus. Consequently, zoonotic infections with avian influenza viruses bearing one of these hemagglutinins may cause enhanced disease in mammals. Influenza viruses from birds can cause outbreaks in humans and may contribute to the development of pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its main surface protein, an H1 subtype hemagglutinin, was identified as a key mammalian virulence factor. In a previous study, a 1918 virus expressing an avian H1 gene was as virulent in mice as the reconstructed 1918 virus. Here, a set of avian influenza viruses was constructed, differing only by hemagglutinin subtype. Viruses with the avian H1, H6, H7, H10, and H15 subtypes caused severe disease in mice and damaged human lung cells. Consequently, infections with avian influenza viruses bearing one of these hemagglutinins may cause enhanced disease in mammals, and therefore surveillance for human infections

Adaptive pathways of zoonotic influenza viruses: from exposure to establishment in humans.

Science.gov (United States)

Reperant, Leslie A; Kuiken, Thijs; Osterhaus, Albert D M E

2012-06-22

Human influenza viruses have their ultimate origin in avian reservoirs and may adapt, either directly or after passage through another mammalian species, to circulate independently in the human population. Three sets of barriers must be crossed by a zoonotic influenza virus before it can become a human virus: animal-to-human transmission barriers; virus-cell interaction barriers; and human-to-human transmission barriers. Adaptive changes allowing zoonotic influenza viruses to cross these barriers have been studied extensively, generating key knowledge for improved pandemic preparedness. Most of these adaptive changes link acquired genetic alterations of the virus to specific adaptation mechanisms that can be screened for, both genetically and phenotypically, as part of zoonotic influenza virus surveillance programs. Human-to-human transmission barriers are only sporadically crossed by zoonotic influenza viruses, eventually triggering a worldwide influenza outbreak or pandemic. This is the most devastating consequence of influenza virus cross-species transmission. Progress has been made in identifying some of the determinants of influenza virus transmissibility. However, interdisciplinary research is needed to further characterize these ultimate barriers to the development of influenza pandemics, at both the level of the individual host and that of the population. Copyright © 2012 Elsevier Ltd. All rights reserved.

Spatiotemporal Analysis of the Genetic Diversity of Seal Influenza A(H10N7) Virus, Northwestern Europe

DEFF Research Database (Denmark)

Bodewes, Rogier; Zohari, Siamak; Krog, Jesper Schak

2016-01-01

and Denmark. Within a few months, this virus spread to seals of the coastal waters of Germany and the Netherlands, causing the death of thousands of animals. Genetic analysis of the hemagglutinin (HA) and neuraminidase (NA) genes of this seal influenza A(H10N7) virus revealed that it was most closely related...... to various avian influenza A(H10N7) viruses. The collection of samples from infected seals during the course of the outbreak provided a unique opportunity to follow the adaptation of the avian virus to its new seal host. Sequence data for samples collected from 41 different seals from four different......, various sequencing methods were used to elucidate the genetic changes that occurred after the introduction and subsequent spread of an avian influenza A(H10N7) virus among harbor seals of northwestern Europe by use of various samples collected during the outbreak. Such detailed knowledge of genetic...

Avian influenza overview September–November 2017

DEFF Research Database (Denmark)

Brown, Ian; Kuiken, Thijs; Mulatti, Paolo

2017-01-01

Between 1 September and 15 November 2017, 48 A(H5N8) highly pathogenic avian influenza (HPAI) outbreaks in poultry holdings and 9 H5 HPAI wild bird events were reported within Europe. A second epidemic HPAI A(H5N8) wave started in Italy on the third week of July and is still ongoing on 15November...... to focus in order to achieve the most effective testing of dead birds for detection of H5 HPAI viruses. Monitoring the avian influenza situation in other continents revealed the same risks as in the previous report (October 2016-August 2017): the recent human case of HPAI A(H5N6) in China underlines...... the continuing threat of this avian influenza virus to human health and possible introduction via migratory wild birds into Europe. Close monitoring is required of the situation in Africa with regards to HPAI of the subtypes A(H5N1) and A(H5N8), given the rapidity of the evolution and the uncertainty...

Is sunspot activity a factor in influenza pandemics?

Science.gov (United States)

Qu, Jiangwen

2016-09-01

The 2009 AH1N1 pandemic became a global health concern, although fortunately, its worst anticipated effects were not realised. While the origins of such outbreaks remain poorly understood, it is very important to identify the precipitating factors in their emergence so that future pandemics can be detected as quickly as possible. Methords: Descriptive epidemiology was used to analyse the association between influenza pandemics and possible pandemics and relative number of sunspots. Non-conditional logistic regression was performed to analyse the statistical association between sunspot extremes and influenza pandemics to within plus or minus 1 year. Almost all recorded influenza/possible pandemics have occurred in time frames corresponding to sunspot extremes, or +/- 1 year within such extremes. These periods were identified as important risk factors in both possible and confirmed influenza pandemics (odds ratio: 3.87; 95% confidence interval: 1.08 to 13.85). Extremes of sunspot activity to within plus or minus 1 year may precipitate influenza pandemics. Mechanisms of epidemic initiation and early spread are discussed including primary causation by externally derived viral variants (from space via cometary dust). Efforts to construct a comprehensive early warning system for potential influenza and other viral pandemics that include analysis of sunspot activity and stratospheric sampling for viral variants should be supported. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A data-driven model for influenza transmission incorporating media effects.

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Mitchell, Lewis; Ross, Joshua V

2016-10-01

Numerous studies have attempted to model the effect of mass media on the transmission of diseases such as influenza; however, quantitative data on media engagement has until recently been difficult to obtain. With the recent explosion of 'big data' coming from online social media and the like, large volumes of data on a population's engagement with mass media during an epidemic are becoming available to researchers. In this study, we combine an online dataset comprising millions of shared messages relating to influenza with traditional surveillance data on flu activity to suggest a functional form for the relationship between the two. Using this data, we present a simple deterministic model for influenza dynamics incorporating media effects, and show that such a model helps explain the dynamics of historical influenza outbreaks. Furthermore, through model selection we show that the proposed media function fits historical data better than other media functions proposed in earlier studies.

Evolution of Therapeutic Antibodies, Influenza Virus Biology, Influenza, and Influenza Immunotherapy

Directory of Open Access Journals (Sweden)

Urai Chaisri

2018-01-01

Full Text Available This narrative review article summarizes past and current technologies for generating antibodies for passive immunization/immunotherapy. Contemporary DNA and protein technologies have facilitated the development of engineered therapeutic monoclonal antibodies in a variety of formats according to the required effector functions. Chimeric, humanized, and human monoclonal antibodies to antigenic/epitopic myriads with less immunogenicity than animal-derived antibodies in human recipients can be produced in vitro. Immunotherapy with ready-to-use antibodies has gained wide acceptance as a powerful treatment against both infectious and noninfectious diseases. Influenza, a highly contagious disease, precipitates annual epidemics and occasional pandemics, resulting in high health and economic burden worldwide. Currently available drugs are becoming less and less effective against this rapidly mutating virus. Alternative treatment strategies are needed, particularly for individuals at high risk for severe morbidity. In a setting where vaccines are not yet protective or available, human antibodies that are broadly effective against various influenza subtypes could be highly efficacious in lowering morbidity and mortality and controlling unprecedented epidemic/pandemic. Prototypes of human single-chain antibodies to several conserved proteins of influenza virus with no Fc portion (hence, no ADE effect in recipients are available. These antibodies have high potential as a novel, safe, and effective anti-influenza agent.

Streptococcus pneumoniae Coinfection Is Correlated with the Severity of H1N1 Pandemic Influenza

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Cisterna, Daniel; Savji, Nazir; Bussetti, Ana Valeria; Kapoor, Vishal; Hui, Jeffrey; Tokarz, Rafal; Briese, Thomas; Baumeister, Elsa; Lipkin, W. Ian

2009-01-01

Background Initial reports in May 2009 of the novel influenza strain H1N1pdm estimated a case fatality rate (CFR) of 0.6%, similar to that of seasonal influenza. In July 2009, however, Argentina reported 3056 cases with 137 deaths, representing a CFR of 4.5%. Potential explanations for increased CFR included virus reassortment or genetic drift, or infection of a more vulnerable population. Virus genomic sequencing of 26 Argentinian samples representing both severe and mild disease indicated no evidence of reassortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence. Furthermore, no evidence was found for increased frequency of risk factors for H1N1pdm disease. Methods/Principal Findings We examined nasopharyngeal swab samples (NPS) from 199 cases of H1N1pdm infection from Argentina with MassTag PCR, testing for 33 additional microbial agents. The study population consisted of 199 H1N1pdm-infected subjects sampled between 23 June and 4 July 2009. Thirty-nine had severe disease defined as death (n = 20) or hospitalization (n = 19); 160 had mild disease. At least one additional agent of potential pathogenic importance was identified in 152 samples (76%), including Streptococcus pneumoniae (n = 62); Haemophilus influenzae (n = 104); human respiratory syncytial virus A (n = 11) and B (n = 1); human rhinovirus A (n = 1) and B (n = 4); human coronaviruses 229E (n = 1) and OC43 (n = 2); Klebsiella pneumoniae (n = 2); Acinetobacter baumannii (n = 2); Serratia marcescens (n = 1); and Staphylococcus aureus (n = 35) and methicillin-resistant S. aureus (MRSA, n = 6). The presence of S. pneumoniae was strongly correlated with severe disease. S. pneumoniae was present in 56.4% of severe cases versus 25% of mild cases; more than one-third of H1N1pdm NPS with S. pneumoniae were from subjects with severe disease (22 of 62 S. pneumoniae-positive NPS, p = 0

Spatial and temporal association of outbreaks of H5N1 influenza virus infection in wild birds with the 0 degrees C isotherm.

Directory of Open Access Journals (Sweden)

Leslie A Reperant

2010-04-01

Full Text Available Wild bird movements and aggregations following spells of cold weather may have resulted in the spread of highly pathogenic avian influenza virus (HPAIV H5N1 in Europe during the winter of 2005-2006. Waterbirds are constrained in winter to areas where bodies of water remain unfrozen in order to feed. On the one hand, waterbirds may choose to winter as close as possible to their breeding grounds in order to conserve energy for subsequent reproduction, and may be displaced by cold fronts. On the other hand, waterbirds may choose to winter in regions where adverse weather conditions are rare, and may be slowed by cold fronts upon their journey back to the breeding grounds, which typically starts before the end of winter. Waterbirds will thus tend to aggregate along cold fronts close to the 0 degrees C isotherm during winter, creating conditions that favour HPAIV H5N1 transmission and spread. We determined that the occurrence of outbreaks of HPAIV H5N1 infection in waterbirds in Europe during the winter of 2005-2006 was associated with temperatures close to 0 degrees C. The analysis suggests a significant spatial and temporal association of outbreaks caused by HPAIV H5N1 in wild birds with maximum surface air temperatures of 0 degrees C-2 degrees C on the day of the outbreaks and the two preceding days. At locations where waterbird census data have been collected since 1990, maximum mallard counts occurred when average and maximum surface air temperatures were 0 degrees C and 3 degrees C, respectively. Overall, the abundance of mallards (Anas platyrhynchos and common pochards (Aythya ferina was highest when surface air temperatures were lower than the mean temperatures of the region investigated. The analysis implies that waterbird movements associated with cold weather, and congregation of waterbirds along the 0 degrees C isotherm likely contributed to the spread and geographical distribution of outbreaks of HPAIV H5N1 infection in wild birds in

Nrf2 Expression Modifies Influenza A Entry and Replication inNasal Epithelial Cells

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Influenza infection is a major cause of morbidity and mortality worldwide, especially during pandemics outbreaks. Emerging data indicate that phase II antioxidant enzyme pathways could playa role in virus-associated inflammation and immune clearance. While Nrf2-dependent gene exp...

Isolation and molecular characterization of an H5N1 swine influenza virus in China in 2015.

Science.gov (United States)

Wu, Haibo; Yang, Fan; Lu, Rufeng; Xu, Lihua; Liu, Fumin; Peng, Xiuming; Wu, Nanping

2018-03-01

In 2015, an H5N1 influenza virus was isolated from a pig in Zhejiang Province, Eastern China. This strain was characterized by whole-genome sequencing with subsequent phylogenetic analysis. Phylogenetic analysis showed that all segments from this strain belonged to clade 2.3.2 and that it had received its genes from poultry influenza viruses in China. A Glu627Lys mutation associated with pathogenicity was observed in the PB2 protein. This strain was moderately pathogenic in mice and was able to replicate without prior adaptation. These results suggest that active surveillance of swine influenza should be used as an early warning system for influenza outbreaks in mammals.

Influenza C infections in Western Australia and Victoria from 2008 to 2014.

Science.gov (United States)

Jelley, Lauren; Levy, Avram; Deng, Yi-Mo; Spirason, Natalie; Lang, Jurissa; Buettner, Iwona; Druce, Julian; Blyth, Chris; Effler, Paul; Smith, David; Barr, Ian G

2016-11-01

Influenza C is usually considered a minor cause of respiratory illness in humans with many infections being asymptomatic or clinically mild. Large outbreaks can occur periodically resulting in significant morbidity. This study aimed at analyzing the available influenza C clinical samples from two widely separated states of Australia, collected over a 7-year period and to compare them with influenza C viruses detected in other parts of the world in recent years. Between 2008 and 2014, 86 respiratory samples that were influenza C positive were collected from subjects with influenza-like illness living in the states of Victoria and Western Australia. A battery of other respiratory viruses were also tested for in these influenza C-positive samples. Virus isolation was attempted on all of these clinical samples, and gene sequencing was performed on all influenza C-positive cultures. Detections of influenza C in respiratory samples were sporadic in most years studied, but higher rates of infection occurred in 2012 and 2014. Many of the patients with influenza C had coinfections with other respiratory pathogens. Phylogenetic analysis of the full-length hemagglutinin-esterase-fusion (HE) gene found that most of the viruses grouped in the C/Sao Paulo/378/82 clade with the remainder grouping in the C/Kanagawa/1/76 clade. © 2016 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Adaptive evolution during the establishment of European avian-like H1N1 influenza A virus in swine.

Science.gov (United States)

Joseph, Udayan; Vijaykrishna, Dhanasekaran; Smith, Gavin J D; Su, Yvonne C F

2018-04-01

An H1N1 subtype influenza A virus with all eight gene segments derived from wild birds (including mallards), ducks and chickens, caused severe disease outbreaks in swine populations in Europe beginning in 1979 and successfully adapted to form the European avian-like swine (EA-swine) influenza lineage. Genes of the EA-swine lineage that are clearly segregated from its closest avian relatives continue to circulate in swine populations globally and represent a unique opportunity to study the adaptive process of an avian-to-mammalian cross-species transmission. Here, we used a relaxed molecular clock model to test whether the EA-swine virus originated through the introduction of a single avian ancestor as an entire genome, followed by an analysis of host-specific selection pressures among different gene segments. Our data indicated independent introduction of gene segments via transmission of avian viruses into swine followed by reassortment events that occurred at least 1-4 years prior to the EA-swine outbreak. All EA-swine gene segments exhibit greater selection pressure than avian viruses, reflecting both adaptive pressures and relaxed selective constraints that are associated with host switching. Notably, we identified key amino acid mutations in the viral surface proteins (H1 and N1) that play a role in adaptation to new hosts. Following the establishment of EA-swine lineage, we observed an increased frequency of intrasubtype reassortment of segments compared to the earlier strains that has been associated with adaptive amino acid replacements, disease severity and vaccine escape. Taken together, our study provides key insights into the adaptive changes in viral genomes following the transmission of avian influenza viruses to swine and the early establishment of the EA-swine lineage.

Risk factors associated with hospitalisation for influenza-associated severe acute respiratory illness in South Africa: A case-population study.

Science.gov (United States)

Abadom, Tochukwu Raphael; Smith, Adrian D; Tempia, Stefano; Madhi, Shabir A; Cohen, Cheryl; Cohen, Adam L

2016-11-04

Influenza is a common cause of severe respiratory illness, but risk factors for hospitalisation in low income settings with a high HIV prevalence are not well described. We aimed to assess risk factors associated with influenza-associated severe acute respiratory illness (SARI) hospitalisation in South Africa. We conducted a case-population study using data on risk conditions in patients hospitalised with SARI and the national prevalence of these conditions. Data on hospitalised cases were from the national SARI surveillance program while data on the referent population were from the latest national census or health and demographic surveillance surveys. From 2009 to 2012, we identified 3646 (7.9%) of 46,031 enrolled cases of SARI that were associated with influenza infection. Risk factors associated with hospitalisation included previous history of smoking [case-population ratio (CPR) 3.82, 95% confidence interval (CI) 3.5-4.16], HIV infection (CPR 3.61, 95% CI 3.5-3.71), asthma (CPR 2.45, 95% CI 2.19-2.73), previous history of hospital admission in the past 12months (CPR 2.07, 95% CI 1.92-2.23), and tuberculosis (CPR 1.85, 95% CI 1.68-2.02). When stratified by age, there is increased risk of hospitalisation in those ⩽5yearsof age (CPR 3.07, 95% CI 2.93-3.21) and among those 35yearsof age and above (CPR 1.23, 95% CI 1.28-1.18). Male sex (CPR 0.85, 95% CI 0.82-0.88) and completion of pneumococcal conjugate vaccination schedule in children <5yearsof age (CPR 0.74, 95% CI 0.71-0.77) were associated with decreased risk of hospitalisation. These results identify groups at high-risk for severe influenza who should be considered potential targets for influenza vaccination in South Africa and similar settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influenza A (H3N2) virus in swine at agricultural fairs and transmission to humans, Michigan and Ohio, USA, 2016

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An 18 case outbreak of variant H3N2 influenza A occurred during 2016 after exposure to influenza-infected swine at seven agricultural fairs. Sixteen cases were infected with a reassortant between 2010-2011 human seasonal H3N2 strains and viruses endemic in North American swine, a viral lineage incre...

Use of oseltamivir in Dutch nursing homes during the 2004-2005 influenza season.

NARCIS (Netherlands)

Sande, Marianne A B van der; Ruijs, Wilhelmina L M; Meijer, Adam; Cools, Herman J M; Plas, Simone M van der

2006-01-01

To assess the implementation of guidelines for using neuraminidase inhibitors in the control of influenza outbreaks in Dutch nursing homes, data were collected on prophylactic and therapeutic use of anti-viral medication, indications for use and criteria for prescribing, based on experiences during

Implementation of Non-Pharmaceutical Interventions by New York City Public Schools to Prevent 2009 Influenza A

Science.gov (United States)

Agolory, Simon G.; Barbot, Oxiris; Averhoff, Francisco; Weiss, Don; Wilson, Elisha; Egger, Joseph; Miller, Jeffery; Ogbuanu, Ikechukwu; Walton, Sabrina; Kahn, Emily

2013-01-01

Introduction Children are important transmitters of influenza in the community and a number of non-pharmaceutical interventions (NPIs), including hand washing and use of hand sanitizer, have been recommended to mitigate the transmission of influenza, but limited information is available regarding schools' ability to implement these NPIs during an influenza outbreak. We evaluated implementation of NPIs during fall 2009 in response to H1N1 pandemic influenza (pH1N1) by New York City (NYC) public schools. Methods From January 25 through February 9, 2010, an online survey was sent to all the 1,632 NYC public schools and principals were asked to participate in the survey or to designate a school nurse or other school official with knowledge of school policies and characteristics to do so. Results Of 1,633 schools, 376(23%) accessed and completed the survey. Nearly all respondents (99%) implemented at least two NPIs. Schools that had a Flu Response Team (FRT) as a part of school emergency preparedness plan were more likely to implement the NPI guidelines recommended by NYC public health officials than schools that did not have a FRT. Designation of a room for isolating ill students, for example, was more common in schools with a FRT (72%) than those without (53%) (peffects of an influenza outbreak is feasible, but there is potential need for additional resources in some schools to increase capacity and adherence to all recommendations. Public health influenza-preparedness plans should include school preparedness planning and FRTs. PMID:23341877

Implementation of non-pharmaceutical interventions by New York City public schools to prevent 2009 influenza A.

Science.gov (United States)

Agolory, Simon G; Barbot, Oxiris; Averhoff, Francisco; Weiss, Don; Wilson, Elisha; Egger, Joseph; Miller, Jeffery; Ogbuanu, Ikechukwu; Walton, Sabrina; Kahn, Emily

2013-01-01

Children are important transmitters of influenza in the community and a number of non-pharmaceutical interventions (NPIs), including hand washing and use of hand sanitizer, have been recommended to mitigate the transmission of influenza, but limited information is available regarding schools' ability to implement these NPIs during an influenza outbreak. We evaluated implementation of NPIs during fall 2009 in response to H1N1 pandemic influenza (pH1N1) by New York City (NYC) public schools. From January 25 through February 9, 2010, an online survey was sent to all the 1,632 NYC public schools and principals were asked to participate in the survey or to designate a school nurse or other school official with knowledge of school policies and characteristics to do so. Of 1,633 schools, 376(23%) accessed and completed the survey. Nearly all respondents (99%) implemented at least two NPIs. Schools that had a Flu Response Team (FRT) as a part of school emergency preparedness plan were more likely to implement the NPI guidelines recommended by NYC public health officials than schools that did not have a FRT. Designation of a room for isolating ill students, for example, was more common in schools with a FRT (72%) than those without (53%) (pschool system to mitigate the effects of an influenza outbreak is feasible, but there is potential need for additional resources in some schools to increase capacity and adherence to all recommendations. Public health influenza-preparedness plans should include school preparedness planning and FRTs.

Evidence for subclinical avian influenza virus infections among rural Thai villagers.

Science.gov (United States)

Khuntirat, Benjawan P; Yoon, In-Kyu; Blair, Patrick J; Krueger, Whitney S; Chittaganpitch, Malinee; Putnam, Shannon D; Supawat, Krongkaew; Gibbons, Robert V; Pattamadilok, Sirima; Sawanpanyalert, Pathom; Heil, Gary L; Friary, John A; Capuano, Ana W; Gray, Gregory C

2011-10-01

Regions of Thailand reported sporadic outbreaks of A/H5N1 highly pathogenic avian influenza (HPAI) among poultry between 2004 and 2008. Kamphaeng Phet Province, in north-central Thailand had over 50 HPAI poultry outbreaks in 2004 alone, and 1 confirmed and 2 likely other human HPAI infections between 2004 and 2006. In 2008, we enrolled a cohort of 800 rural Thai adults living in 8 sites within Kamphaeng Phet Province in a prospective study of zoonotic influenza transmission. We studied participants' sera with serologic assays against 16 avian, 2 swine, and 8 human influenza viruses. Among participants (mean age 49.6 years and 58% female) 65% reported lifetime poultry exposure of at least 30 consecutive minutes. Enrollees had elevated antibodies by microneutralization assay against 3 avian viruses: A/Hong Kong/1073/1999(H9N2), A/Thailand/676/2005(H5N1), and A/Thailand/384/2006(H5N1). Bivariate risk factor modeling demonstrated that male gender, lack of an indoor water source, and tobacco use were associated with elevated titers against avian H9N2 virus. Multivariate modeling suggested that increasing age, lack of an indoor water source, and chronic breathing problems were associated with infection with 1 or both HPAI H5N1 strains. Poultry exposure was not associated with positive serologic findings. These data suggest that people in rural central Thailand may have experienced subclinical avian influenza infections as a result of yet unidentified environmental exposures. Lack of an indoor water source may play a role in transmission.

Surveillance for early detection of low pathogenicity avian influenza in poultry

NARCIS (Netherlands)

Comin, A.

2012-01-01

Infection with low pathogenicity avian influenza (LPAI) virus is widespread and has led to outbreaks in domestic birds in many countries. Although infection does not pose a serious concern for animal heath, LPAI virus subtypes H5 and H7 can mutate into the highly pathogenic form (HPAI), which can

The emergence of influenza A H7N9 in human beings 16 years after influenza A H5N1: a tale of two cities.

Science.gov (United States)

To, Kelvin K W; Chan, Jasper F W; Chen, Honglin; Li, Lanjuan; Yuen, Kwok-Yung

2013-09-01

Infection with either influenza A H5N1 virus in 1997 or avian influenza A H7N9 virus in 2013 caused severe pneumonia that did not respond to typical or atypical antimicrobial treatment, and resulted in high mortality. Both viruses are reassortants with internal genes derived from avian influenza A H9N2 viruses that circulate in Asian poultry. Both viruses have genetic markers of mammalian adaptation in their haemagglutinin and polymerase PB2 subunits, which enhanced binding to human-type receptors and improved replication in mammals, respectively. Hong Kong (affected by H5N1 in 1997) and Shanghai (affected by H7N9 in 2013) are two rapidly flourishing cosmopolitan megacities that were increasing in human population and poultry consumption before the outbreaks. Both cities are located along the avian migratory route at the Pearl River delta and Yangtze River delta. Whether the widespread use of the H5N1 vaccine in east Asia-with suboptimum biosecurity measures in live poultry markets and farms-predisposed to the emergence of H7N9 or other virus subtypes needs further investigation. Why H7N9 seems to be more readily transmitted from poultry to people than H5N1 is still unclear. Copyright © 2013 Elsevier Ltd. All rights reserved.

Streptococcus pneumoniae and Haemophilus influenzae as etiological agents of conjunctivitis outbreaks in the region of Ribeirão Preto, SP, Brazil