The interplay of climate, intervention and imported cases as determinants of the 2014 dengue outbreak in Guangzhou
Cheng, Qu et al. (2020), The interplay of climate, intervention and imported cases as determinants of the 2014 dengue outbreak in Guangzhou, Dryad, Dataset, https://doi.org/10.6078/D17X14
Dengue is a fast spreading mosquito-borne disease that affects more than half of the population worldwide. An unprecedented outbreak happened in Guangzhou, China in 2014, which contributed 52 percent of all dengue cases that occurred in mainland China between 1990 and 2015. Our previous analysis, based on a deterministic model, concluded that the early timing of the first imported case that triggered local transmission and the excessive rainfall thereafter were the most important determinants of the large final epidemic size in 2014. However, the deterministic model did not allow us to explore the driving force of the early local transmission. Here, we expand the model to include stochastic elements and calculate the successful invasion rate of cases that entered Guangzhou at different times under different climate and intervention scenarios. The conclusion is that the higher number of imported cases in May and June was responsible for the early outbreak instead of climate. Although the excessive rainfall in 2014 did increase the success rate, this effect was offset by the low initial water level caused by interventions in late 2013. The success rate is strongly dependent on mosquito abundance during the recovery period of the imported case, since the first step of a successful invasion is infecting at least one local mosquito. The average final epidemic size of successful invasion decreases exponentially with introduction time, which means if an imported case in early summer initiates the infection process, the final number infected can be extremely large. Therefore, dengue outbreaks occurring in Thailand, Singapore, Malaysia and Vietnam in early summer merit greater attention, since the travel volumes between Guangzhou and these countries are large. As the climate changes, destroying mosquito breeding sites in Guangzhou can mitigate the detrimental effects of the probable increase in rainfall in spring and summer.
Columns 1-19 represent parameter values. The meaning of each parameter is shown in Table 1.
PassFail represents the passing or failing status, with 1 stands for passing and 0 stands for failing
National Natural Science Foundation of China, Award: 81273139
Guangdong Natural Science Foundation, Award: S2013010013637
Guangdong Natural Science Foundation, Award: 2015A030313784
Cyrus Tang Foundation
Project for Key Medicine Discipline Construction of Guangzhou Municipality, Award: 2017-2019-04
Collaborative innovation project of Bureau of Science and technology of Guangzhou Municipality, Award: 201508020263