Predicting suitability of regions for Zika outbreaks with zero-inflated models trained using climate data

Abstract

16In recent years, Zika spread through the Americas. This virus has been linked to 17 Guillain-Barré syndrome, which can lead to paralysis, and microcephaly, a severe birth 18 defect. Zika is primarily transmitted by Aedes (Ae.) aegypti, a mosquito whose geographic 19 range has expanded and is anticipated to continue shifting as the climate changes. 20 We used statistical models to predict regional suitability for autochthonous Zika 21 transmission using climatic variables. By suitability for Zika, we mean the potential for an 22 outbreak to occur based on the climate's habitability for Ae. aegypti. We trained zero-2 23 inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) regression models to 24 predict Zika outbreak suitability using 20 subsets of climate variables for 102 regions. 25 Variable subsets were selected for the final models based on importance to Ae. aegypti 26 survival and their performance in aiding prediction of Zika-suitable regions. We 27 determined the two best models to both be ZINB models. The best model's regressors 28 were winter mean temperature, yearly minimum temperature, and population, and the 29 second-best model's regressors were winter mean temperature and population. 30 These two models were then run on bias-corrected climate projections to predict 31 future climate suitability for Zika, and they generated reasonable predictions. The 32 predictions find that most of the sampled regions are expected to become more suitable 33 for Zika outbreaks. The regions with the greatest risk have increasingly mild winters and 34 high human populations. These predictions are based on the most extreme scenario for 35 climate change, which we are currently on track for. 36 37 Author Summary: 38 In recent years, Zika spread through the Americas. This virus has been linked to 39 Guillain-Barré syndrome, which can lead to paralysis, and microcephaly, a severe birth 40 defect. Zika is primarily transmitted by Aedes (Ae.) aegypti, a mosquito whose geographic 41 range has expanded and is anticipated to continue shifting as the climate changes. We 42 used statistical models to predict regional suitability for locally-acquired Zika cases using 43 climatic variables. By suitability for Zika, we mean the potential for an outbreak to occur 44 based on the climate's habitability for Ae. aegypti. We trained statistical models to predict 45 Zika outbreak suitability using 20 subsets of climate variables for 102 regions. Variable 3 46 subsets were selected for the final two models based on importance to Ae. aegypti 47 survival and their performance in aiding prediction of Zika-suitable regions. These two 48 models were then run on climate projections to predict future climate suitability for Zika, 49 and they generated reasonable predictions. The predictions find that most of the sampled 50 regions are expected to become more suitable for Zika outbreaks. The regions with the 51 greatest risk have high human populations and increasingly mild winters. 52 53

Modeling Seasonal Malaria Transmission: A Methodology Connecting Regional Temperatures to Mosquito and Parasite Developmental Traits

“…Additionally, regions where malaria elimination has been successful risk re-introduction of the disease, with a higher risk for temperate regions such as Western Europe and parts of the US as these regions harbor the malaria transmitting Anopheles species mosquitoes (CDC, 2020). In fact, the aforementioned is true for many other mosquito-borne diseases, with observable seasonal trends and variable disease transmission burden associated to temperature and the locality, as well as the fact that shifting climatic patterns is affecting mosquito abundance and redistribution (Roth et al, 2019;Shapiro et al, 2017).…”