A comparative analysis of Chikungunya and Zika transmission

Abstract

The recent global dissemination of Chikungunya and Zika has fostered public health concern worldwide. To better understand the drivers of transmission of these two arboviral diseases, we propose a joint analysis of Chikungunya and Zika epidemics in the same territories, taking into account the common epidemiological features of the epidemics: transmitted by the same vector, in the same environments, and observed by the same surveillance systems. We analyse eighteen outbreaks in French Polynesia and the French West Indies using a hierarchical time-dependent SIR model accounting for the eect of virus, location and weather on transmission, and based on a disease specic serial interval. We show that Chikungunya and Zika have similar transmission potential in the same territories (transmissibility ratio between Zika and Chikungunya of 1.04 [95% credible interval: 0.97; 1.13]), but that detection and reporting rates were dierent (around 19% for Zika and 40% for Chikungunya). Temperature variations between 22• C and 29• C did not alter transmission, but increased precipitation showed a dual eect, rst reducing transmission after a two-week delay, then increasing it around ve weeks later. The present study provides valuable information for risk assessment and introduces a modelling framework for the comparative analysis of arboviral infections that can be extended to other viruses and territories.

A comparison of mosquito densities, weather and infection rates of Aedes aegypti during the first epidemics of Chikungunya (2014) and Zika (2016) in areas with and without vector control in Puerto Rico

“…Similarly, a comparison of Chikungunya and Zika epidemics suggested similar transmission potential in the same areas (Riou et al ., ). Variations among localities in the importance of weather parameters, such as temperature and precipitation, and their potential impact on both vectors and viruses have been reported (He et al ., ; Lourenço et al ., ; Riou et al ., ). Other variables that are important to consider in the dynamics of these epidemics, but perhaps more difficult to evaluate, are differences in the vector competence of Ae.…”

Global expansion and redistribution of Aedes-borne virus transmission risk with climate change

“…albopictus , found that the A1B and B1 scenarios (older climate change scenarios, roughly comparable to intermediate scenarios RCP 6.0 and 4.5 in current climate assessments) both correspond to substantial increases in chikungunya risk surrounding the Mediterranean [29]. An ecological niche modeling study conducted early in the Zika epidemic found that dengue is likely to expand far more significantly due to climate change than Zika [10] (but epidemiological differences among these three viruses remain unresolved [30–32]). While the combined role of climate change and El Niño has been posited as a possible driver of the Zika pandemic’s severity [10], there is little evidence that anomalous climate conditions were a necessary precursor for Zika transmission.…”

Transfusion risk associated with recent arbovirus outbreaks in French Polynesia

“…The dynamics of ZIKV and CHIKV outbreaks were similar with the same transmission potential when spreading in the same territories . The time distribution of the weekly number of contaminated blood donations during ZIKV and CHIKV outbreaks shows a correlation with the incidence of the disease in the overall population (Figs and ).…”