Vasconcelos P F, Da Rosa J F, Da Rosa A P, Dégallier N, Pinheiro F de P, Sá Filho G C
Instituto Evandro Chagas, Centro Colaborador da OMS em Arboviroses, Fundação SESP, Belém, Pará, Brasil.
Rev Inst Med Trop Sao Paulo. 1991 Nov-Dec;33(6):465-76.
An overview of ecological, epidemiological and clinical findings of potential arthropod-borne encephalitis viruses circulating in the Amazon Region of Brazil are discussed. These viruses are the Eastern Equine Encephalitis (EEE), Western Equine Encephalitis (WEE), St. Louis Encephalitis (SLE), Mucambo (MUC) and Pixuna (PIX). These last two are subtypes (III and IV) of Venezuelan Equine Encephalitis virus. The areas of study were the highways and projects of development, as well as places where outbreaks of human diseases caused by arboviruses had been detected. These viruses are widespread in all Amazonia, and at least four of them, EEE, WEE, SLE and MUC are pathogenic to man. EEE and WEE infections were detected by serology, while SLE and MUC by either serology and virus isolation. The PIX virus has the lowest prevalence and, it was isolated in only a few cases, one being from a laboratory infection. Wild birds are the main hosts for all these viruses, except MUC, whose major hosts are rodents. The symptoms presented by infected people were generally a mild febrile illness. Although, jaundice was observed in two individuals from whom SLE was isolated. A comparison of the clinical symptoms presented by the patients in the Amazon Region and other areas of America, especially in the USA is made. In Brazilian Amazon region epidemics have not been detected although, at least, one EEE epizootic was recorded in Bragança, Para State, in 1960. At that time, of 500 horses that were examined 61% were positive to EEE by HI and of them 8.2% died. On the other hand, SLE has caused four epizootics in a forest near Belem. Wild birds and sentinel monkeys were infected, but no human cases were reported.
本文讨论了在巴西亚马逊地区传播的潜在节肢动物传播脑炎病毒的生态学、流行病学和临床研究结果。这些病毒包括东部马脑炎病毒（EEE）、西部马脑炎病毒（WEE）、圣路易斯脑炎病毒（SLE）、穆坎博病毒（MUC）和皮苏纳病毒（PIX）。后两种病毒是委内瑞拉马脑炎病毒的亚型（III型和IV型）。研究区域包括高速公路和开发项目，以及已检测到虫媒病毒引起人类疾病暴发的地点。这些病毒在整个亚马逊地区广泛传播，其中至少四种病毒，即EEE、WEE、SLE和MUC对人类具有致病性。通过血清学检测到了EEE和WEE感染，而SLE和MUC则通过血清学和病毒分离检测到。PIX病毒的流行率最低，仅在少数病例中分离到，其中一例来自实验室感染。野生鸟类是所有这些病毒的主要宿主，但MUC除外，其主要宿主是啮齿动物。感染者的症状通常为轻度发热疾病。不过，从两名分离出SLE的患者身上观察到了黄疸症状。本文对亚马逊地区和美国其他地区，特别是美国患者出现的临床症状进行了比较。尽管1960年在帕拉州的布拉干萨记录了至少一次EEE动物疫情，但在巴西亚马逊地区尚未检测到疫情。当时，在检查的500匹马中，61%通过血凝抑制试验对EEE呈阳性反应，其中8.2%死亡。另一方面，SLE在贝伦附近的一片森林中引发了四次动物疫情。野生鸟类和哨兵猴受到感染，但未报告人类病例。
