. "A12 Southern Hemisphere, Northern Hemisphere: A Global Influenza World." The Domestic and International Impacts of the 2009-H1N1 Influenza A Pandemic: Global Challenges, Global Solutions: Workshop Summary. Washington, DC: The National Academies Press, 2010.
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The Domestic and International Impacts of the 2009-H1N1 Influenza a Pandemic: Global Challenges, Global Solutions - Workshop Summary
Temporal Occurrence
Attention has been drawn to the influence of season on times of influenza occurrence. Influenza had been thought to be a winter infection. It clearly occurs in temperate zones with a recognizable disease burden, but in the tropics and subtropics? A meeting was convened in Singapore in late 1988 with influenza colleagues from around the Pacific Basin with an emphasis on those from Asia. Although much of the data were rudimentary or incomplete, generalized patterns of occurrence were discernible and are shown in Figure A12-1 (Reichelderfer et al., 1989). The winter occurrence in northern Asia was consistent with winter elsewhere, but in tropical and subtropical zones the influenza virus was present for much of the year or year-round, often with a peak at the hottest, weather-
FIGURE A12-1 General patterns of temporal occurrence of influenza A and B viruses in eastern Asia and Australasia.
