Oropouche直鼻病毒(OROV)是一种由mid传播的虫媒病毒,已在整个中美洲和南美洲爆发。在巴西,人类病例历来集中在该国北部地区。人类的Oropouche热范围从轻微的临床症状到罕见的神经系统事件,在巴西被认为是一种被忽视的热带病。由于与其他虫媒病毒的临床相似性,例如基孔肯雅热和登革热病毒,OROV感染可能被低估。2014年在巴西北部和东北部的阿马帕州和巴伊亚州首次发现基孔肯雅病毒(CHIKV)病例。分别。OROV和CHIKV都会引起非特异性症状,在虫媒病毒循环的情况下,使临床诊断变得困难。旨在调查位于巴西亚马逊的阿马帕州CHIKV引入期间的OROV传播,我们对2014年8月至2015年5月收集的发热病例(N=166)进行了回顾性分子学(RT-qPCR)和血清学调查.使用RT-qPCR,所有急性血清样品的OROVRNA均为阴性。然而,使用斑块减少中和试验(PRNT90)在10.24%(17/166)的患者中检测到OROV的中和抗体,中和抗体滴度在20至≥640之间,表明患者先前曾接触过OROV。关于CHIKV,通过在20.25%(33/163)的患者中检测到CHIKVRNA和在28.57%(44/154)的患者中检测到抗CHIKVIgM,证实了近期暴露.在12.58%(19/151)的发热患者中额外检测到抗CHIKVIgG,这表明某些人以前曾接触过CHIKV。此处报告的OROV暴露是否发生在阿马帕的CHIKV循环之前或期间,是未知的,但是因为这些虫媒病毒感染具有相似的临床症状和体征,在引入外来虫媒病毒的过程中,可能会发生一种无声的空气中虫媒病毒循环,并强调了综合征病例监测对巴西虫媒病毒的重要性。
Oropouche orthobunyavirus (OROV) is an
arbovirus transmitted by midges that has been involved in outbreaks throughout Central and South America. In Brazil, human cases have been historically concentrated in the northern region of the country. Oropouche fever in humans range from mild clinical signs to rare neurological events, and is considered a neglected tropical disease in Brazil. Due to the clinical similarities to other arboviruses, such as chikungunya and dengue viruses, OROV infections are likely to be underreported. Chikungunya virus (CHIKV) cases in Brazil were first recognized in 2014 in the states of Amapá and Bahia in the north and northeast regions, respectively. Both OROV and CHIKV cause nonspecific symptoms, making clinical diagnosis difficult in a scenario of
arbovirus cocirculation. Aiming to investigate OROV transmission during the CHIKV introduction in the state of Amapá located in the Brazilian Amazon, we conducted a retrospective molecular (RT-qPCR) and serological investigation in febrile cases (N = 166) collected between August 2014 and May 2015. All acute serum samples were negative for OROV RNA using RT-qPCR. However, neutralizing antibodies for OROV were detected using a plaque reduction neutralization test (PRNT90) in 10.24% (17/166) of the patients, with neutralizing antibody titers ranging from 20 to ≥640, suggesting the previous exposure of patients to OROV. Regarding CHIKV, recent exposure was confirmed by the detection of CHIKV RNA in 20.25% (33/163) of the patients and by the detection of anti-CHIKV IgM in 28.57% (44/154) of the patients. The additional detection of anti-CHIKV IgG in 12.58% (19/151) of the febrile patients suggests that some individuals had been previously exposed to CHIKV. Whether the OROV exposure reported here occurred prior or during the CHIKV circulation in Amapá, is unknown, but because those arboviral infections share similar clinical signs and symptoms, a silent circulation of enzootic arboviruses during the introduction of exotic arboviruses may occur, and highlights the importance of syndromic cases\' surveillance to arboviruses in Brazil.