Lockdowns to Contain COVID-19 Increase Risk and Severity of Mosquito-Borne Disease Outbreaks

Akshay Jindal; Shrisha Rao

is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.04.11.20061143 doi: medRxiv preprint of cases even doubled in some cases relative to the full-lockdown configuration. This increase in cases can be attributed to the increased mobility of infections over larger distances enabled by the few human agents still moving across the population in partial lockdowns, while also preserving the mosquitoes' advantage in being able to infect more humans. This result suggests that additional care must be taken to see that essential workers who continue to be mobile in lockdowns do not carry mosquito-borne diseases, and that others who may carry such infections are not allowed to move around. We further analyzed how the impact of lockdowns varies across three mosquito-borne diseases: chikungunya, dengue and malaria. We found that dengue outbreaks are more severe than chikungunya in any situation even though they share the same vector, Aedes Aegypti. This is because the dengue virus is transmissible from humans to mosquitoes even during late intrinsic incubation stage and early recovered stage. This in turn allows movement of infections by means of humans who are infectious but not showing symptoms (ironically in a manner similar to COVID-19). We also observed that the effects of lockdowns are less pronounced on malaria outbreaks, as they are spread by female Anopheles mosquitoes which are generally active during the night, a time where most humans are stationary with or without lockdowns.