Researchers to examine Virginia's food system and antimicrobial resistance in sheep and goat populations, a possible surveillance blind spot
September 8, 2022
The National Institute of Food and Agriculture (NIFA)/USDA has granted $150,000 for a three-year study of antimicrobial resistance in small ruminant agrosystems. Patrick Pithua, associate professor of Epidemiology in the Department of Health Sciences at Virginia-Maryland College of Veterinary Medicine and Eunice Ndegwa, assistant professor of Agriculture Research at Virginia State University, will lead the research.
Pithua and Ndegwa will examine Virginia's food systems to determine the number of sheep and goats raised and slaughtered in the Commonwealth infected with antimicrobial-resistant Campylobacter spp, Salmonella and E. coli. The researchers will reach out to Virginia farmers and veterinarians to determine what they know about antimicrobial resistance, how they feel about it, and how they treat their small ruminants with antimicrobial medicines.
Antimicrobial resistance refers to when the genes of disease-causing agents mutate or transfer, allowing microbes to survive antimicrobial treatment—this means that medications that have successfully cured microbial infections in the past won't be as effective.
The project has profound public health implications, especially for immigrant populations, who consume the most sheep, lamb and goats in the U.S.
"Emergent diseases usually come from sectors of the population that are neglected, where scientists are not looking for those diseases," said Pithua.
"This is where microbes incubate, spill over into the human population and spread. With swine in the U.S., there's a lot of surveillance on detecting early images of resistant strains of bacteria, but the same isn't being done in goats and sheep. I call those surveillance blind spots, where you're missing an opportunity to detect a disease or an agent that could potentially turn out to be serious."
The research will begin with surveys focusing on the knowledge base of farmers in the state of Virginia.
"We want to know what small ruminant farmers know about antimicrobial resistance because they are a key part of mitigating it. We can't really do the work without involving the farmers themselves, so they're our starting point: Do they understand that antimicrobial resistance is a problem? Do they know what to do to minimize the problem? What kind of antimicrobials do they use to treat conditions on their farms? Do they involve veterinarians in any kind of treatment decisions and so on. We want to get that preliminary knowledge because then we can design extension and education programs that target where there is a knowledge gap on the farmers' side. We can help them employ practices that minimize the emergence of antimicrobial resistance on their farms, and this is really important for antimicrobial stewardship."
Antimicrobial stewardship refers to a coordinated program that promotes the appropriate use of antimicrobials and antibiotics to decrease the spread of infections caused by multidrug-resistant organisms. Over the grant's three-year duration, Pithua will lead and implement these stewardship practices in livestock food systems throughout Virginia. As the research progresses, he will foster relationships with farmers and veterinarians to increase antimicrobial stewardship practices.
"I hope to engage farmers in an informed way to mitigate antimicrobial resistance. My long-term goal is to empower small ruminant producers by giving them the tools to address animal health challenges economically and sustainably."
In addition to being a public health concern, emerging diseases from microbes resistant to antibiotics can also be economically devastating. Pithua said, "There's a huge economic downturn with a foodborne disease outbreak. We've all read about recalls where factories or farms have to recall all of the food products because of an outbreak. That's a large economic loss that many of these companies face frequently. This research is important because food safety has implications beyond public health."
The funding opportunity from the NIFA is especially exciting for Pithua, as this project grew out of work he's done before.
"It was an idea I had in the back of my mind to look for surveillance gaps or these pockets of livestock populations in the U.S. that have been overlooked in terms of the surveillance for foodborne diseases. My team argued that by not providing resources that would enable scientists to understand better what kind of manure cycle pathogens harbored by those surveilled species, we would probably be putting individuals who consume those animals for food at risk. With small agro ruminants that disproportionately affects immigrant populations who consume the most lamb, sheep and goat. This is another reason why investing in food safety is so important and why we are trained to ensure and contribute to the health of all people."