Lim JT, Dickens BSL, Chew LZX, et al. Impact of SARS-CoV-2 interventions on dengue transmission. PLoS Negl Trop Dis. 2020: 14(10): e0008719
Social distancing measures are not a standard intervention to reduce transmission of vector-borne diseases such as dengue, due to their minimal influence on vector dynamics versus targeted vector control.
However, social distancing introduced due to SARS-CoV-2 provides an opportunity for a natural experiment.
social distancing introduced due to SARS-CoV-2 provides an opportunity for a natural experiment
Lim et al. therefore used reported dengue case counts when social distancing was implemented in Malaysia, Singapore and Thailand to estimate its effect on dengue cases.
Prior to social distancing, average monthly numbers of reported dengue cases per 10,000 population were 1.15 in Thailand, 2.15 in Singapore, and 0.31 in Malaysia.
With implementation of social distancing, and taking into account factors such as seasonality, climate, and time trends, the number of cases in Thailand is estimated to increase by 0.431 per 10,000 population per province.
Conversely, due to social distancing, the number of dengue cases in Singapore and Malaysia is estimated to decrease by 0.036 and 0.004 per 10,000 population, respectively.
However, these effects were not significant, even when seasonality, climate, and time trends were taken into account.
Lim et al. concluded that social distancing could lead to an increase in dengue cases in Thailand but would have no significant impact in Singapore or Malaysia.