ABSTRACT
To assess the impact of absolute humidity on influenza transmission in Beijing from 2014 to 2019, we estimated the influenza transmissibility via the instantaneous reproduction number (Rt), and evaluated its nonlinear exposure-response association and delayed effects with absolute humidity by using the distributed lag nonlinear model (DLNM). Attributable fraction (AF) of Rt due to absolute humidity was calculated. The result showed a significant M-shaped relationship between Rt and absolute humidity. Compared with the effect of high absolute humidity, the low absolute humidity effect was more immediate with the most significant effect observed at lag 6 days. AFs were relatively high for the group aged 15–24 years, and was the lowest for the group aged 0–4 years with low absolute humidity. Therefore, we concluded that the component attributed to the low absolute humidity effect is greater. Young and middle-aged people are more sensitive to low absolute humidity than children and elderly.
Acknowledgments
We are grateful to the staff members in district and municipal CDCs, and medical settings in Beijing for conducting field investigation, specimen collection, laboratory detection and case reporting.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Author contribution
Li Zhang: Writing – original draft, methodology. Chunna Ma: investigation. Wei Duan: investigation. Jie Yuan: methodology. Shuangsheng Wu: data curation. Ying Sun: data curation. Jiaojiao Zhang: editing. Jue Liu: supervision. Quanyi Wang: supervision, resources. Min Liu: conceptualization, project administration.
Data availability
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.