Estudos transversais sobre Vaccinia virus em Minas Gerais, Brasil: Circulação viral em população urbana e Avaliação do conhecimento de profissionais de saúde em área hiperendêmica

Abstract

The Orthopoxvirus (OPV) genus comprises emerging viruses of significant importance in both human and veterinary medicine, including Variola virus (VARV) and Vaccinia virus (VACV). In South America, VACV is responsible for outbreaks of bovine vaccinia (BV), an occupational zoonosis whose classical transmission route is direct contact between humans and infected cattle. However, reports of cases unrelated to cattle have suggested the existence of alternative routes of viral transmission. Two pilot cross-sectional studies were conducted. The first assessed VACV circulation in the urban population of an endemic area. For this, serum samples were collected from 61 individuals residing in the urban area of Serro, an endemic municipality in the state of Minas Gerais, Brazil. The serum samples were tested using an enzyme-linked immunosorbent assay (ELISA) and a virus neutralization test (VNT) to detect IgG and neutralizing antibodies, respectively. In addition, an epidemiological survey was carried out to investigate potential risk factors. Among the 61 participants, 20 tested positive for IgG antibodies, corresponding to an overall seroprevalence of 32.8%, while 22 individuals (36%) had neutralizing antibodies. The exposure factor “presence of vaccination scar” was statistically significant in association with antibody presence (p < 0.05). The second study, also conducted in Serro, assessed healthcare professionals' knowledge of BV. Fifty-one individuals (49.5% of the town’s healthcare workforce) participated in the study. Among them, 22 tested positive for IgG antibodies, corresponding to an overall prevalence of 43.1%, and 12 individuals (23.5%) had neutralizing antibodies with titers ranging from 100 to 6,400 neutralizing units/mL. Twenty-nine participants (56.9%) reported having heard of BV. Eleven (21.6%) had witnessed a BV outbreak, and only five (9.8%) reported knowing the etiological agent. These findings reveal a lack of preparedness among healthcare professionals regarding BV in Brazil and highlight the need for improved communication about the disease in affected areas. An educational resource was developed to provide information on BV. It is believed that educating the affected population, field veterinarians, animal health authorities, and public health personnel on various aspects of BV could reduce its impact on human and animal health. Moreover, such education would be essential to contain the emergence of VACV in urbanized areas.