A retrospective analysis on the association between seasonality of influenza A and climate factors in human from 1997 to 2008,in Hong Kong / 中华流行病学杂志

ABSTRACT

Objective To investigate the association between seasonal dynamics of influenza A and climate factors in Hong Kong.Methods Data regarding monthly report on influenza A and climate during the period of 1997-2008 were collected.Generalized additive models were established to study the effects of climate factors on the seasonality of influenza A in human while confounders controlled and nonlinear effect determined.Results Results showed that the association between climate factors and the seasonality of influenza A was complicated.The nonlinear effects of climate factors on the epidemics of influenza A were significant,using x2 test (P＜0.05).The effect of the factors including mean temperature,relative humidity,wind speed and absolute humidity on the seasonality of influenza A were similar,maximal at low scale,minimal at mid-rang scale and moderate at high one.The minamal effect intervals of the above factors were (17.95-24.10) ℃,(71.5-78.5 )％,(18.3-24.0) km/h and (4.37-4.80)mb respectively.Conclusion Data from this study suggested that the effect of climate factors on the seasonal dynamics of influenza A in human was complicated.