Large-scale Lassa fever outbreaks in Nigeria: quantifying the association between disease reproduction number and local rainfall

Shi Zhao; Salihu S. Musa; Hao Fu; Daihai He; Jing Qin

ï‚· p-value: 0.044) with a regression R-squared of 0.36. We report the most significant (i.e., with the lowest p-value) regression estimates that appear with a cumulative lag of 7 months. The habitats of the LASV reservoir, i.e., rodents, include irrigated and flooded agricultural lands that are commonly found in and around African villages [6] . The range of lag from 4-9 months has previously been explained by the time interval between the peak of the rainfall and the rodent population [7] . The association between rodent population dynamics and rainfall levels has been demonstrated in a number of previous studies [6-10]. This relation could also be verified by examining the rodent population data in the Nigerian regions included in this work. The present finding of the impact of lagged rainfall on LF outbreaks suggests that knowledge of such weather-driven epidemics could be gained by referring to past rainfall levels. For instance, if a relatively high amount of rainfall occurs, local measures, such as rodent population control, could be effective to reduce the LF risk. The findings in this work are of public health interest and are helpful for policy-makers trying to achieve LF prevention and control.