Correlation between seasonal influenza and meteorological factors: a systematic review

  Objective  To explore the correlation between seasonal influenza activity level and meteorological factors.

  Methods  A literature retrieval of papers about influenza activity and meteorological factors published by May 2019 in English electronic databases, such as Pubmed, Cochrane Library, OVID, EBSCO and Web of Science, was conducted. A total of 45 qualified literatures were included, including laboratory and epidemiological surveys. Research sites of epidemiological studies were stratified according to different climatic regions, and basic information, meteorological factors and statistical methods of the included literatures were extracted, classified and analyzed.

  Results  Most epidemiological studies used some type of regression analysis. Influenza activity in temperate region was significantly associated with low temperature and low humidity. The correlation between influenza activity and temperature or humidity in subtropical and tropical regions were complex and inconsistent, and rainfall might increase the level of influenza activity in tropical region.

  Conclusion  Environmental factors, such as cold and dry climate in temperate region and humid and rainy climate in tropical region, are closely related to influenza activity, but the information about the influence of meteorological factors, such as solar radiation, wind speed, and atmospheric pressure, on influenza activity is still limited.