The effect of ambient temperature on the activity influenza like illness andlaboratory-confirmed influenza in Wuxi City / 中华疾病控制杂志

ABSTRACT

Objective To evaluate the effect of ambient temperature on the activity influenza like illness (ILI) and laboratory-confirmed influenza (LAB) in Wuxi City. Methods Daily data of meteorological, ILI and detected influenza virus from 31 December 2012 to 31 December 2017 were collected. Distributed lag non-linear model (DLNM) was used to evaluate the exposure-lag-response of ILI and LAB activity to daily ambient temperature.Results During the period, the overall ILI% was 4.96% and influenza detection positive rate was 12.28% in Wuxi city. The overall cumulative association analysis suggested non-linear relationship between ambient temperature and influenza: U-shaped for ILI, while L-shaped relationship for LAB. Low temperature (＜10℃ ) had strong and longer delay effect than hightemperature (＞20℃ ) for ILI. The cold effect for LAB was stronger and longer delay，and the low temperature (＜10℃ ) was risk factor for LAB. Conclusions The ambient temperature significant correlates with ILI and LAB, and low temperature might be risk factor with lag effect.