Secundino Nagila Francinete Costa, Chaves Barbara Aparecida, Orfano Alessandra Silva, Silveira Karine Renata Dias, Rodrigues Nilton Barnabe, Campolina Thais Bonifácio, Nacif-Pimenta Rafael, Villegas Luiz Eduardo Martinez, Silva Breno Melo, Lacerda Marcus Vinícius Guimarães, Norris Douglas Eric, Pimenta Paulo Filemon Paolucci
Laboratory of Medical Entomology, René Rachou Research Centre - FIOCRUZ-MG, Belo Horizonte, Minas Gerais, Brazil.
Tropical Medicine Foundation Dr. Heitor Vieira Dourado, Manaus, Amazonas, Brazil.
Parasit Vectors. 2017 Jul 20;10(1):346. doi: 10.1186/s13071-017-2286-2.
Zika disease has transformed into a serious global health problem due to the rapid spread of the arbovirus and alarming severity including congenital complications, microcephaly and Guillain-Barré syndrome. Zika virus (ZIKV) is primarily transmitted to humans through the bite of an infective mosquito, with Aedes aegypti being the main vector.
We successfully developed a ZIKV experimental transmission model by single infectious Ae. aegypti bite to a laboratory mouse using circulating Brazilian strains of both arbovirus and vector. Mosquitoes were orally infected and single Ae. aegypti were allowed to feed on mouse ears 14 days post-infection. Additionally, salivary gland (SG) homogenates from infected mosquitoes were intrathoracically inoculated into naïve Ae. aegypti. Mosquito and mouse tissue samples were cultured in C6/36 cells and processed by quantitative real-time PCR.
A total of 26 Ae. aegypti were allowed to feed individually on mouse ears. Of these, 17 mosquitoes fed, all to full engorgement. The transmission rate of ZIKV by bite from these engorged mosquitoes to mouse ears was 100%. The amount of virus inoculated into the ears by bites ranged from 2 × 10-2.1 × 10 ZIKV cDNA copies and was positively correlated with ZIKV cDNA quantified from SGs dissected from mosquitoes post-feeding. Replicating ZIKV was confirmed in macerated SGs (2.45 × 10 cDNA copies), mouse ear tissue (1.15 × 10 cDNA copies, and mosquitoes 14 days post-intrathoracic inoculation (1.49 × 10 cDNA copies) by cytopathic effect in C6/36 cell culture and qPCR.
Our model illustrates successful transmission of ZIKV by an infectious mosquito bite to a live vertebrate host. This approach offers a comprehensive tool for evaluating the development of infection in and transmission from mosquitoes, and the vertebrate-ZIKV interaction and progression of infection following a natural transmission process.
由于虫媒病毒的迅速传播以及包括先天性并发症、小头畸形和吉兰 - 巴雷综合征在内的令人担忧的严重性，寨卡病已演变成一个严重的全球健康问题。寨卡病毒（ZIKV）主要通过感染性蚊子的叮咬传播给人类，埃及伊蚊是主要传播媒介。
我们使用巴西循环的虫媒病毒株和传播媒介，通过单只感染性埃及伊蚊叮咬实验室小鼠，成功建立了寨卡病毒实验性传播模型。蚊子经口感染，感染后14天让单只埃及伊蚊叮咬小鼠耳朵。此外，将感染蚊子的唾液腺（SG）匀浆经胸腔接种到未感染的埃及伊蚊体内。蚊子和小鼠组织样本在C6/36细胞中培养，并通过定量实时PCR进行处理。
总共让26只埃及伊蚊分别叮咬小鼠耳朵。其中，17只蚊子叮咬并全部饱食。这些饱食的蚊子叮咬小鼠耳朵后寨卡病毒的传播率为100%。叮咬接种到耳朵中的病毒量在2×10 - 2.1×10寨卡病毒cDNA拷贝之间，并且与喂食后从蚊子解剖得到的唾液腺中定量的寨卡病毒cDNA呈正相关。通过C6/36细胞培养中的细胞病变效应和qPCR在匀浆的唾液腺（2.45×10 cDNA拷贝）、小鼠耳朵组织（1.15×10 cDNA拷贝）以及胸腔接种后14天的蚊子（1.49×10 cDNA拷贝）中证实了寨卡病毒的复制。
我们的模型表明感染性蚊子叮咬可成功将寨卡病毒传播给活体脊椎动物宿主。这种方法为评估蚊子体内感染的发展、蚊子的传播以及自然传播过程后脊椎动物 - 寨卡病毒相互作用和感染进程提供了一个全面的工具。
