Seasonality, Timing, and Climate Drivers of Influenza Activity Worldwide

Abstract

Annual influenza epidemics occur in consistent temporal patterns depending on climate.

Influenza seasonality and vaccination timing in tropical and subtropical areas of southern and south-eastern Asia

“…Despite differences in surveillance methods, demographic characteristics and environmental factors, 2,3,12,30,31 it was possible to show peaks of influenza circulation in some countries, while in others influenza activity was detected throughout the year. These findings are consistent with the reports from the countries.…”

“…lower temperatures and decreased humidity) may influence both viral transmission and host susceptibility. 3,32,33 Several countries, such as Bangladesh, Brazil, India and Viet Nam, have reported high influenza activity that coincides with rainy seasons, 15,16,19,25 while other countries, such as the Philippines, Singapore and Thailand, have reported semi-annual Influenza seasonality and vaccination timing in south-eastern Asia Siddhartha Saha et al…”

“…between November and March in the northern hemisphere and between April and September in the southern hemipshere. [1][2][3] Data on influenza strains circulating globally are used to predict which strains have the highest probability of circulating in the subsequent season and this information is used to generate recommendations for seasonal influenza vaccine composition. 4 The effectiveness of influenza vaccines depends not only on the right match between vaccine strains and circulating viral Objective To characterize influenza seasonality and identify the best time of the year for vaccination against influenza in tropical and subtropical countries of southern and south-eastern Asia that lie north of the equator.…”

Predictors of Hospitalization and Admission to Intensive Care Units of Influenza Patients in Serbia through Four Influenza Seasons from 2010/2011 to 2013/2014

“…In a temperate climate region, the epidemic of influenza commonly occurs during the autumn and winter months. The outbreak, duration, intensity, and geographical spread of influenza are unpredictable and depend on a number of factors, such as the characteristics of the virus, the sensitivity of the population, climate, and environmental factors (1)(2)(3). Patients requiring hospitalization for severe forms of influenza usually suffer from chronic respiratory disease, asthma, diabetes mellitus, chronic heart disease, chronic kidney disease, or are immunocompromised patients undergoing immunosuppressive therapy or chemotherapy (4,5).…”

Influence of Average Income on Epidemics of Seasonal Influenza

“…Most countries have 1 annual influenza epidemic. In contrast, about half of the tropical countries have 2 or 3 influenza endemics per year (6). The epidemic pattern of seasonal influenza was thought to differ from place to place in Aomori prefecture; however, to our knowledge, no epidemiological study has been performed previously regarding this issue.…”