Henipavírus: Paramixovírus Zoonóticos, Emergentes e Letais

Hendra henipavirus (HeV) e Nipah henipavirus (NiV) sao membros do genero Henipavirus, pertencente a familia Paramyxoviridae, sendo classificados como patogenos de nivel de biosseguranca 4, em funcao de sua alta capacidade em causar doenca letal em seres humanos associada a constituicao genetica unica, carencia de terapia e profilaxia especificas. O reservatorio natural destes virus sao os morcegos pertencentes ao genero Pteropus, encontrados em regioes que se estendem do Pacifico Ocidental a Costa Leste da Africa. O desmatamento e um dos responsaveis pela saida dos morcegos de seus nichos ecologicos e aproximacao de fazendas e vilarejos. Novos casos de infeccao pelo HeV em cavalos continuam ocorrendo na Australia, enquanto o NiV e responsavel por surtos anuais em humanos, desde 2001, na India e Bangladesh. O NiV, em particular, possui varios recursos que destacam seu potencial como ameaca pandemica, incluindo sua capacidade de infectar humanos diretamente, a partir de reservatorios naturais, alem de uma capacidade limitada de transmissao entre seres humanos. Apesar disso, atualmente, pouco se sabe sobre os mecanismos pelos quais os morcegos abrigam virus capazes de causar doencas tao graves em outros mamiferos terrestres. A presente revisao traz informacoes relevantes para o entendimento sobre a epidemiologia destas viroses, a patogenia nas especies suscetiveis, bem como a importância destes virus nas especies domesticas, principalmente, nos equideos. Palavras-chave: Hendra Virus. Nipah Virus. Morcegos. Equinos. Suinos. Abstract Hendra henipavirus (HeV) and Nipah henipavirus (NiV) are members of the genus Henipavirus, belonging to the family Paramyxoviridae, being classified as biosafety level 4 pathogens, due to their high capacity to cause lethal disease in humans associated with their unique genetic constitution, lack of specific therapy and prophylaxis. Bats belonging to the genus Pteropus, found in regions that extend from the Western Pacific to the East coast of Africa, are natural reservoir of such viruses. Deforestation is one of the factors responsible for the bats’ leaving their ecological niches and their adaptation to farms and villages. New cases of HeV infection in horses continue to occur in Australia while NiV has been responsible for annual human outbreaks since 2001 in India and Bangladesh. NiV has several features that highlight its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs, as well as a limited capacity for transmission between humans. Despite this, little is currently known about the mechanisms by which bats harbor viruses capable of causing serious diseases in other terrestrial mammals. This review provides relevant information for understanding the epidemiology of these viruses, the pathogenesis in susceptible species, as well as the importance of these viruses in domestic species, especially in horses. Keywords: Hendra Virus. Nipah Virus. Bats. Horses. Pigs.