Co-infections with bovine herpesvirus type 5 and bovine viral diarrhoea virus

Abstract

A AB BS ST TR RA AC CT TDuring a series of experiments attempting to reproduce clinically apparent bovine herpesvirus type 5 (BoHV-5) infections, a group of calves was inadvertently infected with bovine viral diarrhoea virus (BVDV). Another group of calves was infected with BoHV-5 only. This paper reports the outcome of such infections. Two out of six calves solely infected with BoHV-5 displayed moderate to severe clinical signs. Three out of four calves of the group co-infected with BoHV-5 and BVDV developed severe clinical signs, two of them died. BoHV-5 virus was isolated to higher titres and for a longer period from the group of calves infected with both viruses. These results suggest that BVDV may enhance clinical signs induced by BoHV-5 and may also play a role in extending the period of BoHV-5 shedding.Keywords: BoHV-5, BVDV, co-infection, experimental inoculation RESUMO Durante a realização de experimentos envolvendo inoculações experimentais com herpesvírus bovino tipo 5 (BoHV-5), um grupo de bovinos foi acidentalmente também inoculado com vírus da diarréia viral bovina (BVDV). Os dados obtidos nesta co-infecção foram então comparados a aqueles observados em animais inoculados exclusivamente com

Neurological and epidemiological aspects of a BoHV-5 meningoencephalitis outbreak

“…However, the subacute/chronic case herein presented in which the BoHV-5 infection was manifested as focal caudal brainstem dysfunction (pontomedullary syndrome) could be considered unusual, since subacute/chronic BoHV-5 disease has been typically characterized by diffuse neurological disease with multifocal brain dysfunctions. The remaining neurological deficits observed in this outbreak were similar to those previously described in both naturally and experimentally induced infections (Cascio et al, 1999;Colodel et al, 2002;Perez et al, 2002;Elias et al, 2004;Rissi et al, 2006;2008;Spilki et al, 2006). Histological examination of the brain sections from seven affected calves revealed nervous lesions compatible with viral encephalitis, such as the presence of mild to moderate non-suppurative meningoencephalitis (perivascular cuffing of mononuclear inflammatory cells) (Fig.…”

Histopathological, immunohistochemical, and molecular study of BHV-5 infection in the central nervous system of experimentally infected calves

“…In one study, malacia was associated with fatal cases of BHV-5 infection (Spilki et al 2006); however, in a different study, malacia was not always present in fatal cases (Perez et al 2002). In the present study, malacia was observed in the thalamus and frontal and parietal cortices, similar to a previous study (Rissi et al 2008).…”

Meningoencefalite por herpesvírus bovino-5

“…Além disso, são descritos casos experimentais de infecção por BoHV-5 em que a infecção acidental pelo vírus da diarréia viral bovina (BVD) pode ter exacerbado os sinais clínicos da infecção por BoHV-5 e aumentado a quantidade de vírus excretado pela via nasal (Spilki et al 2006). Esses autores sugerem que ambas as doenças (PEM e BVD) podem ter relação com casos de meningoencefalite por BoHV-5 em situações naturais.…”