Viral factors in influenza pandemic risk assessment.
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ABSTRACT:
SUBMITTER: Lipsitch M
PROVIDER: S-EPMC5156527 | biostudies-literature | 2016 Nov
REPOSITORIES: biostudies-literature
Publications
Viral factors in influenza pandemic risk assessment.
Lipsitch Marc M Barclay Wendy W Raman Rahul R Russell Charles J CJ Belser Jessica A JA Cobey Sarah S Kasson Peter M PM Lloyd-Smith James O JO Maurer-Stroh Sebastian S Riley Steven S Beauchemin Catherine Aa CA Bedford Trevor T Friedrich Thomas C TC Handel Andreas A Herfst Sander S Murcia Pablo R PR Roche Benjamin B Wilke Claus O CO Russell Colin A CA
eLife 20161111
The threat of an influenza A virus pandemic stems from continual virus spillovers from reservoir species, a tiny fraction of which spark sustained transmission in humans. To date, no pandemic emergence of a new influenza strain has been preceded by detection of a closely related precursor in an animal or human. Nonetheless, influenza surveillance efforts are expanding, prompting a need for tools to assess the pandemic risk posed by a detected virus. The goal would be to use genetic sequence and/ ...[more]
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Project description:Data from all reported cases of 2009 pandemic influenza A (H1N1) were obtained from the China Information System for Disease Control and Prevention. The spatiotemporal distribution patterns of cases were characterized through spatial analysis. The impact of travel-related risk factors on invasion of the disease was analyzed using survival analysis, and climatic factors related to local transmission were identified using multilevel Poisson regression, both at the county level. The results showed that the epidemic spanned a large geographic area, with the most affected areas being in western China. Significant differences in incidence were found among age groups, with incidences peaking in school-age children. Overall, the epidemic spread from southeast to northwest. Proximity to airports and being intersected by national highways or freeways but not railways were variables associated with the presence of the disease in a county. Lower temperature and lower relative humidity were the climatic factors facilitating local transmission after correction for the effects of school summer vacation and public holidays, as well as population density and the density of medical facilities. These findings indicate that interventions focused on domestic travel, population density, and climatic factors could play a role in mitigating the public health impact of future influenza pandemics.
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