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Choi JH, Namgung H, Lim SJ, Kim EK, Oh Y, Park YC. Predicting Suitable Areas for African Swine Fever Outbreaks in Wild Boars in South Korea and Their Implications for Managing High-Risk Pig Farms. Animals (Basel) 2023; 13:2148. [PMID: 37443946 DOI: 10.3390/ani13132148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/21/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
African swine fever (ASF) is a highly contagious disease affecting domestic pigs and wild boars, with no effective vaccine or treatment available. In South Korea, extensive measures have been implemented to prevent ASF transmission between wild boars and ASF spillover from wild boars to pig farm sectors, including the search for ASF-infected carcasses in mountainous forests and the installation of fences across wide areas of these forests. To determine the priority search range for infected carcasses and establish pig farm-centered quarantine measures, it is necessary to predict the specific path of ASF outbreaks in wild boars and identify pig farms at high risk of ASF spillover from wild boars. Here, we aimed to predict suitable areas and geographical paths for ASF outbreaks in wild boars using the MaxEnt model and shortest-path betweenness centrality analysis. The analysis identified a high frequency of ASF outbreaks in areas with a suitability value ≥0.4 on the suitability map and in areas within a 1.8 km range from the path on the shortest-path map, indicating these areas were high-risk zones for ASF outbreaks. Among the 5063 pig farms analyzed, 37 were in the high-risk zone on the suitability map, 499 were in the high-risk zone on the shortest-path map, and 9 were in both risk zones. Of the 51 pig farm sectors with a dense distribution of pig farms (kernel density ≥ 8), 25 sectors were in contact with or partially overlapped the high risk zone on the suitability map, 18 sectors were located within the high risk zone on the shortest-path map, and 14 sectors were located within both risk zones. These findings aided in determining the priority range for searches for wild boar carcasses and enabled the establishment of preemptive ASF prevention measures around the pig farming sectors that are at risk of ASF spillover from wild boars.
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Affiliation(s)
- Ju Hui Choi
- College of Forest & Environmental Sciences, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Hun Namgung
- Ecological Survey Division, Korea National Park Research Institute, Wonju 26441, Republic of Korea
| | - Sang Jin Lim
- College of Forest & Environmental Sciences, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Eui Kyeong Kim
- Ecological Survey Division, Korea National Park Research Institute, Wonju 26441, Republic of Korea
| | - Yeonsu Oh
- College of Veterinary Medicine & Institute of Veterinary Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Yung Chul Park
- College of Forest & Environmental Sciences, Kangwon National University, Chuncheon 24341, Republic of Korea
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Salaheldin AH, Kasbohm E, El-Naggar H, Ulrich R, Scheibner D, Gischke M, Hassan MK, Arafa ASA, Hassan WM, Abd El-Hamid HS, Hafez HM, Veits J, Mettenleiter TC, Abdelwhab EM. Potential Biological and Climatic Factors That Influence the Incidence and Persistence of Highly Pathogenic H5N1 Avian Influenza Virus in Egypt. Front Microbiol 2018; 9:528. [PMID: 29636730 PMCID: PMC5880882 DOI: 10.3389/fmicb.2018.00528] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 03/08/2018] [Indexed: 01/09/2023] Open
Abstract
Highly pathogenic H5N1 avian influenza virus (A/H5N1) of clade 2.2.1 is endemic in poultry in Egypt where the highest number of human infections worldwide was reported. During the last 12 years the Egyptian A/H5N1 evolved into several genotypes. In 2007-2014 vaccinated poultry suffered from antigenic drift variants of clade 2.2.1.1 and in 2014/2015 an unprecedented upsurge of A/H5N1 clade 2.2.1.2 occurred in poultry and humans. Factors contributing to the endemicity or re-emergence of A/H5N1 in poultry in Egypt remain unclear. Here, three potential factors were studied: climatic factors (temperature, relative humidity, and wind speed), biological fitness in vitro, and pathogenicity in domestic Pekin and Muscovy ducks. Statistical analyses using negative binomial regression models indicated that ambient temperature in winter months influenced the spread of A/H5N1 in different geographic areas analyzed in this study. In vitro, at 4 and 56°C 2.2.1.1 and recent 2.2.1.2 viruses were more stable than other viruses used in this study. Further, Pekin ducks were more resistant than Muscovy ducks and the viruses were excreted for up to 2 weeks post-infection assuming a strong role as a reservoir. Taken together, ambient temperature in winter months potentially contributes to increasing outbreaks in some regions in Egypt. Heat stability of clade 2.2.1.1 and recent 2.2.1.2 viruses probably favors their persistence at elevated temperatures. Importantly, asymptomatically infected Pekin ducks may play an important role in the spread of avian and human-like A/H5N1 in Egypt. Therefore, control measures including targeted surveillance and culling of silently infected Pekin ducks should be considered.
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Affiliation(s)
- Ahmed H Salaheldin
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany.,Institute of Poultry Diseases, Free University of Berlin, Berlin, Germany.,Department of Poultry Diseases, Faculty of Veterinary Medicine, Alexandria University, Edfina, Egypt
| | - Elisa Kasbohm
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany.,Institute of Mathematics and Computer Science, University of Greifswald, Greifswald, Germany
| | - Heba El-Naggar
- Veterinary Serum and Vaccine Research Institute, Cairo, Egypt
| | - Reiner Ulrich
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - David Scheibner
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Marcel Gischke
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Mohamed K Hassan
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
| | - Abdel-Satar A Arafa
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
| | - Wafaa M Hassan
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
| | | | - Hafez M Hafez
- Institute of Poultry Diseases, Free University of Berlin, Berlin, Germany
| | - Jutta Veits
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Thomas C Mettenleiter
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Elsayed M Abdelwhab
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
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Influenza A H5N1 and H7N9 in China: A spatial risk analysis. PLoS One 2017; 12:e0174980. [PMID: 28376125 PMCID: PMC5380336 DOI: 10.1371/journal.pone.0174980] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/19/2017] [Indexed: 11/19/2022] Open
Abstract
Background Zoonotic avian influenza poses a major risk to China, and other parts of the world. H5N1 has remained endemic in China and globally for nearly two decades, and in 2013, a novel zoonotic influenza A subtype H7N9 emerged in China. This study aimed to improve upon our current understanding of the spreading mechanisms of H7N9 and H5N1 by generating spatial risk profiles for each of the two virus subtypes across mainland China. Methods and findings In this study, we (i) developed a refined data set of H5N1 and H7N9 locations with consideration of animal/animal environment case data, as well as spatial accuracy and precision; (ii) used this data set along with environmental variables to build species distribution models (SDMs) for each virus subtype in high resolution spatial units of 1km2 cells using Maxent; (iii) developed a risk modelling framework which integrated the results from the SDMs with human and chicken population variables, which was done to quantify the risk of zoonotic transmission; and (iv) identified areas at high risk of H5N1 and H7N9 transmission. We produced high performing SDMs (6 of 8 models with AUC > 0.9) for both H5N1 and H7N9. In all our SDMs, H7N9 consistently showed higher AUC results compared to H5N1, suggesting H7N9 suitability could be better explained by environmental variables. For both subtypes, high risk areas were primarily located in south-eastern China, with H5N1 distributions found to be more diffuse and extending more inland compared to H7N9. Conclusions We provide projections of our risk models to public health policy makers so that specific high risk areas can be targeted for control measures. We recommend comparing H5N1 and H7N9 prevalence rates and survivability in the natural environment to better understand the role of animal and environmental transmission in human infections.
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Walsh MG, Amstislavski P, Greene A, Haseeb MA. The Landscape Epidemiology of Seasonal Clustering of Highly Pathogenic Avian Influenza (H5N1) in Domestic Poultry in Africa, Europe and Asia. Transbound Emerg Dis 2016; 64:1465-1478. [DOI: 10.1111/tbed.12537] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Indexed: 12/27/2022]
Affiliation(s)
- M. G. Walsh
- Westmead Clinical School and Marie Bashir Institute for Infectious Diseases and Biosecurity; University of Sydney; Sydney NSW Australia
| | - P. Amstislavski
- Department of Health Sciences; University of Alaska; Anchorage AK USA
| | - A. Greene
- Department of Epidemiology and Biostatistics; School of Public Health; State University of New York Downstate Medical Center; Brooklyn NY USA
| | - M. A. Haseeb
- Department of Epidemiology and Biostatistics; School of Public Health; State University of New York Downstate Medical Center; Brooklyn NY USA
- Departments of Cell Biology, Pathology and Medicine; College of Medicine; State University of New York Downstate Medical Center; Brooklyn NY USA
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Vela EM, Kasoji MD, Wendling MQ, Price JA, Knostman KAB, Bresler HS, Long JP. MicroRNA expression in mice infected with seasonal H1N1, swine H1N1 or highly pathogenic H5N1. J Med Microbiol 2014; 63:1131-1142. [PMID: 24913561 DOI: 10.1099/jmm.0.067959-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Influenza virus infections in humans remain a healthcare concern, and the need for vaccines, therapeutics and prophylactics remains a high priority. Understanding the molecular events associated with influenza-virus-induced pathology may lead to the identification of clinical disease biomarkers and novel antiviral targets. MicroRNAs (miRNAs) are well-conserved endogenous non-coding RNAs known to regulate post-transcriptional gene expression as well as play a major role in many biological processes and pathways. Animal studies have demonstrated that miRNAs are involved in viral disease and controlling inflammation. In this study, we examined the differences in the miRNA expression profiles associated with the lung in mice infected with influenza viruses that varied in virulence and pathogenicity. A statistical model was employed that utilized changes in miRNA expression to identify the virus that was used to infect the mice. This study identified a unique fingerprint of viral pathogenicity associated with seasonal H1N1, swine H1N1 and highly pathogenic H5N1 in the mouse model, and may lead to the identification of novel therapeutic and prophylactic targets.
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Affiliation(s)
- Eric M Vela
- Battelle, 505 King Avenue, Columbus, OH, USA
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Zhu G, Peterson AT. Potential geographic distribution of the novel avian-origin influenza A (H7N9) virus. PLoS One 2014; 9:e93390. [PMID: 24690878 PMCID: PMC3972139 DOI: 10.1371/journal.pone.0093390] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 03/03/2014] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In late March 2013, a new avian-origin influenza virus emerged in eastern China. This H7N9 subtype virus has since infected 240 people and killed 60, and has awakened global concern as a potential pandemic threat. Ecological niche modeling has seen increasing applications as a useful tool in mapping geographic potential and risk of disease transmission. METHODOLOGY/PRINCIPALS We developed two datasets based on seasonal variation in Normalized Difference Vegetation Index (NDVI) from the MODIS sensor to characterize environmental dimensions of H7N9 virus. One-third of well-documented cases was used to test robustness of models calibrated based on the remaining two-thirds, and model significance was tested using partial ROC approaches. A final niche model was calibrated using all records available. CONCLUSIONS/SIGNIFICANCE Central-eastern China appears to represent an area of high risk for H7N9 spread, but suitable areas were distributed more spottily in the north and only along the coast in the south; highly suitable areas also were identified in western Taiwan. Areas identified as presenting high risk for H7N9 spread tend to present consistent NDVI values through the year, whereas unsuitable areas show greater seasonal variation.
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Affiliation(s)
- Gengping Zhu
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, China
- * E-mail:
| | - A. Townsend Peterson
- Biodiversity Institute, University of Kansas, Lawrence, Kansas, United States of America
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Hosseini PR, Fuller T, Harrigan R, Zhao D, Arriola CS, Gonzalez A, Miller MJ, Xiao X, Smith TB, Jones JH, Daszak P. Metapopulation dynamics enable persistence of influenza A, including A/H5N1, in poultry. PLoS One 2013; 8:e80091. [PMID: 24312455 PMCID: PMC3846554 DOI: 10.1371/journal.pone.0080091] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 10/08/2013] [Indexed: 11/18/2022] Open
Abstract
Highly pathogenic influenza A/H5N1 has persistently but sporadically caused human illness and death since 1997. Yet it is still unclear how this pathogen is able to persist globally. While wild birds seem to be a genetic reservoir for influenza A, they do not seem to be the main source of human illness. Here, we highlight the role that domestic poultry may play in maintaining A/H5N1 globally, using theoretical models of spatial population structure in poultry populations. We find that a metapopulation of moderately sized poultry flocks can sustain the pathogen in a finite poultry population for over two years. Our results suggest that it is possible that moderately intensive backyard farms could sustain the pathogen indefinitely in real systems. This fits a pattern that has been observed from many empirical systems. Rather than just employing standard culling procedures to control the disease, our model suggests ways that poultry production systems may be modified.
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Affiliation(s)
| | - Trevon Fuller
- Center for Tropical Research, Institute of the Environment, University of California Los Angeles, Los Angeles, California, United States of America
| | - Ryan Harrigan
- Center for Tropical Research, Institute of the Environment, University of California Los Angeles, Los Angeles, California, United States of America
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Delong Zhao
- Department of Botany and Microbiology, Center for Spatial Analysis, University of Oklahoma, Norman, Oklahoma, United States of America
| | - Carmen Sofia Arriola
- Laboratory of Preventive Veterinary Medicine, School of Veterinary Medicine, San Marcos Major National University, Lima, Peru
| | - Armandoe Gonzalez
- Laboratory of Preventive Veterinary Medicine, School of Veterinary Medicine, San Marcos Major National University, Lima, Peru
| | | | - Xiangming Xiao
- Department of Botany and Microbiology, Center for Spatial Analysis, University of Oklahoma, Norman, Oklahoma, United States of America
| | - Tom B. Smith
- Center for Tropical Research, Institute of the Environment, University of California Los Angeles, Los Angeles, California, United States of America
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Jamie Holland Jones
- Woods Institute for the Environment and Department of Anthropology, Stanford University, Stanford, California, United States of America
| | - Peter Daszak
- EcoHealth Alliance, New York, New York, United States of America
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Si Y, de Boer WF, Gong P. Different environmental drivers of highly pathogenic avian influenza H5N1 outbreaks in poultry and wild birds. PLoS One 2013; 8:e53362. [PMID: 23308201 PMCID: PMC3538778 DOI: 10.1371/journal.pone.0053362] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 11/27/2012] [Indexed: 11/23/2022] Open
Abstract
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. However, previous studies found no difference between these two outbreak types when only the effect of physical environmental factors was analysed. The influence of physical and anthropogenic environmental variables and interactions between the two has only been investigated for wild bird outbreaks. We therefore tested the effect of these environmental factors on HPAI H5N1 outbreaks in poultry, and the potential spread mechanism, and discussed how these differ from those observed in wild birds. Logistic regression analyses were used to quantify the relationship between HPAI H5N1 outbreaks in poultry and environmental factors. Poultry outbreaks increased with an increasing human population density combined with close proximity to lakes or wetlands, increased temperatures and reduced precipitation during the cold season. A risk map was generated based on the identified key factors. In wild birds, outbreaks were strongly associated with an increased Normalized Difference Vegetation Index (NDVI) and lower elevation, though they were similarly affected by climatic conditions as poultry outbreaks. This is the first study that analyses the differences in environmental drivers and spread mechanisms between poultry and wild bird outbreaks. Outbreaks in poultry mostly occurred in areas where the location of farms or trade areas overlapped with habitats for wild birds, whereas outbreaks in wild birds were mainly found in areas where food and shelters are available. The different environmental drivers suggest that different spread mechanisms might be involved: HPAI H5N1 spread to poultry via both poultry and wild birds, whereas contact with wild birds alone seems to drive the outbreaks in wild birds.
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Affiliation(s)
- Yali Si
- Ministry of Education Key Laboratory for Earth System Modeling, and Center for Earth System Science, Tsinghua University, Beijing, China.
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Moriguchi S, Onuma M, Goka K. Potential risk map for avian influenza A virus invading Japan. DIVERS DISTRIB 2012. [DOI: 10.1111/ddi.12006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Affiliation(s)
- Sachiko Moriguchi
- Invasive Alien Species Research Team; National Institute for Environmental Studies; 16-2 Onogawa; Tsukuba; Ibaraki; 305-8506; Japan
| | - Manabu Onuma
- Ecological Genetics Research Section; Center for Environmental Biology and Ecosystem; National Institute for Environmental Studies; 16-2 Onogawa; Tsukuba; Ibaraki; 305-8506; Japan
| | - Koichi Goka
- Invasive Alien Species Research Team; National Institute for Environmental Studies; 16-2 Onogawa; Tsukuba; Ibaraki; 305-8506; Japan
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Vela EM, Buccellato MA, Tordoff K, Stark G, Bigger JE. Efficacy of a heterologous vaccine and adjuvant in ferrets challenged with influenza virus H5N1. Influenza Other Respir Viruses 2012; 6:328-40. [PMID: 22192389 PMCID: PMC3412077 DOI: 10.1111/j.1750-2659.2011.00321.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND In 1997, highly pathogenic avian influenza (HPAI) viruses caused outbreaks of disease in domestic poultry markets in Hong Kong. The virus has also been detected in infected poultry in Europe and Africa. OBJECTIVE The objective of this study was to determine the efficacy of a heterologous vaccine administered with and without the aluminum hydroxide adjuvant in ferrets challenged with HPAI (A/Vietnam/1203/04). METHODS Animals in four of the five groups were vaccinated twice 21 days apart, with two doses of a heterologous monovalent subvirion vaccine with or without an aluminum hydroxide adjuvant and challenged with a lethal target dose of A/Vietnam/1203/04. RESULTS All animals vaccinated with the heterologous vaccine in combination with the aluminum hydroxide adjuvant survived a lethal challenge of A/Vietnam/1203/04. Four of the eight animals vaccinated with 30 μg of the vaccine without the adjuvant survived, while two of the eight animals vaccinated with 15 μg of the vaccine without the adjuvant survived. None of the unvaccinated control animals survived challenge. Additionally, changes in virus recovered from nasal washes and post-mortem tissues and serology suggest vaccine efficacy. CONCLUSIONS Altogether, the data suggest that the heterologous vaccine in combination with the aluminum hydroxide adjuvant offers maximum protection against challenge with A/Vietnam/1203/04 when compared to the unvaccinated control animals or animals vaccinated without any adjuvant.
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Affiliation(s)
- Eric M Vela
- Battelle, 505 King Avenue, Columbus, OH 43201, USA.
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Gilbert M, Pfeiffer DU. Risk factor modelling of the spatio-temporal patterns of highly pathogenic avian influenza (HPAIV) H5N1: a review. Spat Spatiotemporal Epidemiol 2012; 3:173-83. [PMID: 22749203 PMCID: PMC3389348 DOI: 10.1016/j.sste.2012.01.002] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 11/25/2011] [Accepted: 01/30/2012] [Indexed: 10/14/2022]
Abstract
Highly pathogenic avian influenza virus (HPAIV) H5N1 continues to impact on smallholder livelihoods, to constrain development of the poultry production sector, and to cause occasional human fatalities. HPAI H5N1 outbreaks have occurred in a variety of ecological systems with economic, agricultural and environmental differences. This review aimed to identify common risk factors amongst spatial modelling studies conducted in these different agro-ecological systems, and to identify gaps in our understanding of the disease's spatial epidemiology. Three types of variables with similar statistical association with HPAI H5N1 presence across studies and regions were identified: domestic waterfowl, several anthropogenic variables (human population density, distance to roads) and indicators of water presence. Variables on socio-economic conditions, poultry trade, wild bird distribution and movements were comparatively rarely considered. Few studies have analysed the HPAI H5N1 distribution in countries such as Egypt and Indonesia, where HPAIV H5N1 continues to circulate extensively.
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Affiliation(s)
- Marius Gilbert
- Biological Control and Spatial Ecology, Université Libre de Bruxelles, av FD Roosevelt 50, B-1050 Brussels, Belgium.
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