In the last decade, Flaviviruses such as yellow fever (YFV) and Zika (ZIKV) have expanded their transmission areas. These viruses originated in Africa, where they exhibit both sylvatic and interhuman transmission cycles. In Brazil, the risk of YFV urbanization has grown, with the sylvatic transmission approaching the most densely populated metropolis, while concern about ZIKV spillback to a sylvatic cycle has risen. To investigate these health threats, we carried out extensive collections and arbovirus screening of 144 free-living, non-human primates (NHPs) and 5219 mosquitoes before, during, and after ZIKV and YFV outbreaks (2015-2018) in southeast Brazil. ZIKV infection was not detected in any NHP collected at any time. In contrast, current and previous YFV infections were detected in NHPs sampled between 2017 and 2018, but not before the onset of the YFV outbreak. Mosquito pools screened by high-throughput PCR were positive for YFV when captured in the wild and during the YFV outbreak, but were negative for 94 other arboviruses, including ZIKV, regardless of the time of collection. In conclusion, there was no evidence of YFV transmission in coastal southeast Brazil before the current outbreak, nor the spread or establishment of an independent sylvatic cycle of ZIKV or urban Aedes aegypti transmission of YFV in the region. In view of the region's receptivity and vulnerability to arbovirus transmission, surveillance of NHPs and mosquitoes should be strengthened and continuous.

中文翻译：

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对非人类灵长类动物和蚊子的调查没有提供黄热病和寨卡病毒在巴西东南部严重爆发后城市和森林循环之间溢出/回溢的证据。

在过去十年中，黄热病（YFV）和寨卡病毒（ZIKV）等黄病毒扩大了传播范围。这些病毒起源于非洲，在那里它们表现出森林传播和人际传播循环。在巴西，随着森林传播逼近人口最稠密的大都市，YFV 城市化的风险有所增加，同时对 ZIKV 回流到森林循环的担忧也有所增加。为了调查这些健康威胁，我们在巴西东南部 ZIKV 和 YFV 爆发之前、期间和之后（2015-2018 年）对 144 只自由生活的非人类灵长类动物 (NHP) 和 5219 只蚊子进行了广泛的收集和虫媒病毒筛查。在任何时间收集的任何 NHP 中均未检测到 ZIKV 感染。相比之下，在 2017 年至 2018 年采样的 NHP 中检测到当前和以前的 YFV 感染，但不是在 YFV 爆发之前。通过高通量 PCR 筛选的蚊子库，在野外捕获和 YFV 爆发期间呈 YFV 阳性，但无论收集时间如何，对包括 ZIKV 在内的 94 种其他虫媒病毒呈阴性。总之，在本次疫情爆发之前，没有证据表明巴西东南部沿海地区存在 YFV 传播，也没有 ZIKV 独立森林循环的传播或建立，也没有 YFV 城市埃及伊蚊在该地区传播的证据。鉴于该地区对虫媒病毒传播的接受性和脆弱性，应加强和持续加强对非人灵长类和蚊子的监测。