Hepacivírus em animais domésticos e silvestres

O vírus da hepatite C (HCV), membro da Família Flaviviridae e do gênero Hepacivirus, é um vírus RNA que infecta 170 milhões de pessoas em todo o mundo, causando insuficiência hepática, hepatite e carcinoma hepatocelular. Aproximadamente 3% da população mundial está cronicamente infectada pelo vírus da hepatite C (HCV), resultando em um alto risco de doenças hepáticas. Até 1996, o HCV era a única espécie conhecida do Gênero Hepacivírus. Desde então, os hepacivírus (HVs) têm sido detectados em diversos animais domésticos e selvagens, incluindo equinos, cães, roedores, morcegos e, mais recentemente, bovinos. Desta forma, uma nova classificação foi proposta, dividindo o gênero em 14 novas espécies (denominadas de A até N). Tendo em vista que não existe um modelo experimental de estudo para HCV e a multiplicação do vírus em cultivo celular é de difícil realização, o estudo de HVs nos diversos hospedeiros animais pode abrir novas áreas de pesquisa para compreender a sua biologia e auxiliar a elucidar a origem e evolução viral do HCV. O entendimento sobre vírus em animais também é importante para a saúde pública e animal, visto que é possível identificar possíveis reservatórios zoonóticos. O objetivo deste trabalho de conclusão é realizar uma revisão bibliográfica a fim de descrever as características dos HVs nos seus diversos hospedeiros, conhecer melhor suas possíveis rotas de infecção e biologia viral. Além disso, visa revisar as teorias relacionadas a origem e evolução viral do HCV e determinar o potencial dos HVs para estabelecer novas infecções zoonóticas.The hepatitis C virus (HCV), member of the Flaviviridae Family and the genus Hepacivirus, is an RNA virus infecting 170 million people worldwide, causing hepatic failure, hepatitis and hepatocellular carcinoma. Approximately 3% of the world's population is chronically infected with the hepatitis C virus (HCV), resulting in a high risk of liver disease. Until 1996, HCV was a single known species of the genus Hepacivirus. Since then, hepaciviruses (HVs) have been detected in several domestic and wild animals, including horses, dogs, rodents, bats and, more recently, cattle. Therefore, a new classification was proposed, dividing the genus in 14 new species (denominated from A to N). Considering that there is no experimental model for HCV and the multiplication of the virus in cell culture is difficult to perform, the study of HVs in the various animal hosts can open new areas of research to understand its biology and to help elucidate the origin and viral evolution of HCV. Understanding of viruses in animals is of utmost importance for public and animal health as it is possible to identify possible zoonotic reservoirs. The objective of this conclusion work is to carry out a bibliographic review in order to describe the characteristics of HVs in their different hosts, to better know their possible routes of infection and viral biology. In addition, it aims to review theories related to the origin and viral evolution of HCV and the potential of HVs to establish zoonotic infections

Causes of fetal death in the Flemish cattle herd in Brazil

Background and Aim: Flemish cattle in Brazil are on the brink of extinction and are found only in one herd in Lages, Santa Catarina State. This study aimed to uncover the reasons for the recurring abortions in the Flemish cattle herd. Materials and Methods: Seventeen Flemish fetuses underwent postmortem examinations, with samples collected for histopathology and microbiology culture tests, polymerase chain reaction (PCR) test for Neospora caninum, and reverse transcription-PCR (RT-PCR) test for bovine viral diarrhea virus (BVDV) from 2015 to 2020. Results: Of the 17 fetuses, N. caninum was the most common diagnosis and was found in 88% (15/17). One fetus (5.8%) had a coinfection with N. caninum and Citrobacter amalonaticus, leading to fibrinonecrotic pericarditis. All fetuses tested negative for BVDV by RT-PCR. Of the 107 dams tested by indirect immunofluorescence assay, 26 (25.2%) were anti-N. caninum seropositive, with 17 (65.4%) aborting and 5 (19.2%) having estrus repetition. Reverse transcription-PCR results showed that 9 (8.4%) of the serum samples collected from dams tested positive, which tested follow-up test 3 months later, indicating a BVDV transient infection. The factors that contributed to neosporosis included dogs’ access to pastures and improper disposal of fetal remains, which made it easier for dogs to consume them. Conclusion: This study warns the occurrence of N. caninum as a cause of reproductive disorders that can lead to abortion in the studied Flemish cattle herd

Serologic evidence of West Nile virus and Saint Louis encephalitis virus in horses from Southern Brazil

Flaviviruses as West Nile virus (WNV), Saint Louis encephalitis virus (SLEV), Ilhéus virus (ILHV), and Rocio virus (ROCV) are previously reported in different Brazilian regions, but studies in Southern Brazil are still scarce. To improve the information regarding flaviviruses in Southern Brazil, horse serum samples were analyzed using RT-qPCR and a commercial ELISA-Ab against WNV followed by PRNT75. All 1000 samples analyzed by real-time RT-PCR resulted negative. The 465 subsampled samples were analyzed by a commercial ELISA-Ab against WNV, and the 18.5% (86/465) positive samples were further analyzed by PRNT75. In the PRNT75, 13/86 and 2/86 horses were positive for SLEV and WNV, respectively. It was observed that 5.8% (13/226) of the farms presented at least one positive animal for SLEV in PRNT75, whereas 0.9% (2/226) for WNV. Apart from the lower seroprevalences identified when compared to data previously reported in other Brazilian regions, our results suggest that public health professionals must be aware of the presence of these potential zoonotic pathogens