SHIC Pursues Information on Novel Rotavirus to Determine Risk to US Swine Herd

The Swine Health Information Center (SHIC) monitors emerging swine disease threats, engaging experts on preparedness, response, and possible actions needed on behalf of the US pork industry. Recently, SHIC inquired with experts regarding a novel rotavirus affecting foals in Kentucky this spring. After consideration, those experts, Drs. Feng Li, University of Kentucky (UK) Gluck Equine Research Center, along with swine experts Albert Rovira, University of Minnesota, Ben Hause, South Dakota State University, and Eric Burrough, Iowa State University, conferred with SHIC and determined there was no need for action as the virus was not a threat to pork production.

“The consensus of the group was that equine rotavirus B was genetically more similar to ruminant as opposed to swine rotavirus B,” Dr. Hause stated. Ruminant genotypes of rotavirus B are found in goats and cattle as opposed to pigs. “We considered the potential for it to transmit to pigs however there was no reason for us to suspect this was likely at this time,” he remarked.

“It’s important SHIC has its ears to the ground, listening for anything emerging in other livestock species. It was right to ask the question. We all have informed opinions but none of us know for sure – we’re ranking risks here. In this case, several diagnosticians looked at it and said while it’s something to keep our eyes on, the threat doesn’t appear to be imminent for swine so there’s no need for further action at this time,” Dr. Hause concluded.

SHIC’s interest in the novel rotavirus was piqued when reports on extensive and evolving rotavirus B outbreaks in central Kentucky this spring surfaced. In an article on response to the outbreaks from the UK Gluck Equine Research Center, it was said farmers and practitioners noticed increases in diarrhea incidence in foals aged 2- to 7-days old. Investigation by the Gluck Center, as well as the UK Veterinary Diagnostic Lab (UKVDL), determined a novel rotavirus was the cause. Current diagnostic tests were unable to detect the pathogen causing diarrhea in very young foals affected, however, the UKVDL has subsequently developed a real-time PCR assay able to detect rotavirus B which was determined to be the cause of these new cases.

SHIC notes rotavirus B is more likely to jump to cattle than pigs, a primary reason to continue to watch its prevalence but without action in the swine industry. Of neonatal diarrhea cases coming to VDLs, over 90% will have some evidence of rotavirus, regardless of the actual cause of the disease. While the A-B-C rotavirus PCR does not pick up this equine virus, next generation sequencing and other tools are available now at reasonable cost making it more likely a new rotavirus strain will be quickly identified than it had been previously. These diagnostic steps and processes are followed by VDLs so rotaviruses are investigated and the process reliable for detection and diagnosis.

SHIC, launched in 2015 with Pork Checkoff funding, continues to focus efforts on prevention, preparedness, and response to novel and emerging swine disease for the benefit of US swine health. As a conduit of information and research, SHIC encourages sharing of its publications and research. Forward, reprint, and quote SHIC material freely. SHIC is funded by America’s pork producers to fulfill its mission to protect and enhance the health of the US swine herd. For more information, visit http://www.swinehealth.org or contact Dr. Sundberg at psundberg@swinehealth.org.