|BAUERMANN, FERNANDO - Universidade Federal De Santa Maria|
Submitted to: Animal Health Research Reviews
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2015
Publication Date: 6/1/2015
Publication URL: http://handle.nal.usda.gov/10113/61212
Citation: Bauermann, F.V., Ridpath, J.F. 2015. HoBi-like viruses – the typical 'atypical bovine pestivirus'. Animal Health Research Reviews. 16(1):64-69. DOI: 10.1017/S146625231500002X.
Interpretive Summary: Bovine viral diarrhea virus (BVDV) infection in cattle results in major economic impact to the cattle industry worldwide. The emerging pestivirus group known as HoBi-like viruses, BVDV-3, or atypical pestiviruses represents a threat for the cattle industry, as the clinical presentation is indistinguishable from BVDV infection in cattle. HoBi-like viruses seem to be endemic in regions within South America and Asia. Outbreaks were also reported in Italy, but there is no indication of the presence of this virus in United States. The full host range is unknown but HoBi-like viruses have been detected in field samples from cattle and water buffalos. While experimentally infected sheep replicate and shed virus, only seroconversion is reported in pigs. Specific commercial diagnostic tests for HoBi-like virus are not available. Although commercial BVDV diagnostics may detect a substantial percentage of HoBi-like viruses, differentiation from BVDV species is not possible with these tests. Further, it appears that newly isolated HoBi-like strains originating from India and Bangladesh may not be detectable using current tests. This review summarizes the current information available regarding HoBi-like viruses including epidemiology, clinical presentation and evaluation of available diagnostic tests.
Technical Abstract: HoBi-like viruses, also referred to as bovine viral diarrhea virus 3 (BVDV-3) and atypical pestivirus, have been proposed as a new putative bovine pestivirus species. These viruses were first identified in the last decade and are currently distributed in at least three continents. Published findings suggest that these viruses may be endemic at least in parts of South America and Asia. The clinical presentations in cattle, described in field outbreaks and controlled studies, are similar to those associated with BVDV and range from subclinical to mild symptoms, sporadically associated with reproductive losses, respiratory illness and hemorrhagic syndrome. The complete host range of HoBi-like virus is unknown, but data suggest higher adaptation of HoBi-like viruses to ruminants as compared to swine. Acute infections, characterized by mild clinical signs, such as low-grade pyrexia and leukopenia, were observed in both cattle and sheep. Virus was isolated from nasal swabs indicating that virus was being shed. While seroconversion was observed in pigs, no clinical presentation or viral shedding was evident following inoculation. While some commercial BVDV diagnostic tests may detect HoBi-like viruses, these tests do not differentiate between BVDV and HoBi-like viruses. The differentiation of BVDV and HoBi-like viruses is critical to the design of surveillance and control programs for these viruses.