Rehfeld Izabelle Silva, Matos Ana Carolina Diniz, Guedes Maria Isabel Maldonado Coelho, Costa Aristóteles Gomes, Fraiha Ana Luiza Soares, Lobato Zélia Inês Portela
Laboratório de Pesquisa em Virologia Animal, Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Brazil.
Laboratório de Pesquisa em Virologia Animal, Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Brazil.
Res Vet Sci. 2017 Oct;114:233-235. doi: 10.1016/j.rvsc.2017.03.022. Epub 2017 Apr 6.
Bovine vaccinia (BV) is a zoonosis caused by Vaccinia virus (VACV) that mainly affects lactating cows and dairy farm milkers. The epidemiological role(s) of other cattle categories such as dry cows, bulls, and heifers in BV remains unclear. This study was performed to investigate VACV in affected dairy cattle herds and perifocal farms during an outbreak in Brazil. Crusts from lesions of cows' teats were collected from all farms with BV outbreaks. Milk, feces, blood, and serum were collected from symptomatic and asymptomatic lactating cows. Blood and serum were also sampled from other cattle categories (calves, heifers, dry cows, and bulls). The samples were tested for VACV by PCR, and to confirm VACV viability, VACV-positive samples were inoculated in BSC-40 cells and stained using immunoperoxidase. Neutralizing antibodies were investigated using plaque reduction neutralization test. Viral DNA was detected in milk, blood, and feces samples of symptomatic and asymptomatic dairy cows and in blood samples from other cattle categories on farms with and without confirmed BV outbreak. In affected farms, viable virus was identified in feces and milk samples from lactating cows and in blood samples from asymptomatic dry cows. Viable VACV was also identified in feces from lactating cows and one bull's blood sample from perifocal farms. Neutralizing antibodies were detected in 81.6% of the herds affected by BV and in 53.8% of the herds on perifocal farms. The presented data indicate a potential source of viral dissemination, which contributes to the persistence and spread of VACV in the environment.
牛痘是由痘苗病毒（VACV）引起的一种人畜共患病，主要影响泌乳奶牛和奶牛场挤奶工。其他牛类别，如干奶牛、公牛和小母牛在牛痘中的流行病学作用仍不清楚。本研究旨在调查巴西一次疫情期间受影响的奶牛群和疫源地周边农场中的痘苗病毒。从所有爆发牛痘的农场收集奶牛乳头病变的痂皮。从有症状和无症状的泌乳奶牛采集牛奶、粪便、血液和血清。还从其他牛类别（犊牛、小母牛、干奶牛和公牛）采集血液和血清。通过聚合酶链反应（PCR）检测样本中的痘苗病毒，为确认痘苗病毒的活力，将痘苗病毒阳性样本接种到BSC - 40细胞中并用免疫过氧化物酶染色。使用蚀斑减少中和试验研究中和抗体。在有和没有确诊牛痘疫情的农场中，在有症状和无症状的泌乳奶牛的牛奶、血液和粪便样本以及其他牛类别的血液样本中检测到病毒DNA。在受影响的农场中，在泌乳奶牛的粪便和牛奶样本以及无症状干奶牛的血液样本中鉴定出活病毒。在泌乳奶牛的粪便和疫源地周边农场一头公牛的血液样本中也鉴定出活的痘苗病毒。在81.6%受牛痘影响的牛群和53.8%疫源地周边农场的牛群中检测到中和抗体。所呈现的数据表明存在病毒传播的潜在来源，这有助于痘苗病毒在环境中的持续存在和传播。
