Abstract:
The incidence of chikungunya has dramatically surged worldwide in recent decades, imposing an expanding burden on public health. In recent years, South America, particularly Brazil, has experienced outbreaks that have ravaged populations following the rapid dissemination of the chikungunya virus (CHIKV), which was first detected in 2014. The primary vector for CHIKV transmission is the urban mosquito species Aedes aegypti, which is highly prevalent throughout Brazil. However, the impact of the locally circulating CHIKV genotypes and specific combinations of local mosquito populations on vector competence remains unexplored. Here, we experimentally analyzed and compared the infectivity and transmissibility of the CHIKV-ECSA lineage recently isolated in Brazil among four Ae. aegypti populations collected from different regions of the country. When exposed to CHIKV-infected AG129 mice for blood feeding, all the mosquito populations displayed high infection rates and dissemination efficiency. Furthermore, we observed that all the populations were highly efficient in transmitting CHIKV to a vertebrate host (naïve AG129 mice) as early as eight days post-infection. These results demonstrate the high capacity of Brazilian Ae. aegypti populations to transmit the locally circulating CHIKV-ECSA lineage. This observation could help to explain the high prevalence of the CHIKV-ECSA lineage over the Asian lineage, which was also detected in Brazil in 2014. However, further studies comparing both lineages are necessary to gain a better understanding of the vector\'s importance in the epidemiology of CHIKV in the Americas.
摘要:
近几十年来,基孔肯雅病的发病率在全球范围内急剧上升,对公共卫生造成越来越大的负担。近年来,南美洲,尤其是巴西,在基孔肯雅病毒(CHIKV)迅速传播之后,它在2014年首次被发现。CHIKV传播的主要媒介是城市蚊子埃及伊蚊,这在整个巴西非常普遍。然而,本地传播的CHIKV基因型和本地蚊子种群的特定组合对媒介能力的影响仍未被研究.这里,我们通过实验分析并比较了最近在巴西分离的CHIKV-ECSA谱系在四个Ae中的传染性和传播性。来自该国不同地区的埃及伊蚊种群。当暴露于感染CHIKV的AG129小鼠进行血液喂养时,所有蚊子的感染率和传播效率都很高。此外,我们观察到,早在感染后8天,所有群体都能高效地将CHIKV传播给脊椎动物宿主(未处理AG129小鼠).这些结果证明了巴西Ae的高容量。埃及伊蚊种群传播当地传播的CHIKV-ECSA谱系。这一观察结果可能有助于解释CHIKV-ECSA谱系在亚洲谱系中的高流行率,2014年在巴西也发现了这种情况。然而,为了更好地了解该媒介在美洲CHIKV流行病学中的重要性,需要对两种谱系进行进一步的比较研究.