As 2023 ushered in hopes for an end to the COVID pandemic, another virus loomed over the country. This one decimating wild birds and reaching into poultry houses where millions of flocks had to be culled. In the media, the soaring price of eggs heralded the arrival of highly pathogenic avian influenza, H5N1.
Surprising as it was to the public, the University of Maryland’s poultry team had been watching and preparing for such an outbreak for many years.
“We’ve been working closely with Maryland poultry farmers on biosecurity for a long time, and they’ve made great strides over the years,” said Jonathan Moyle, state poultry specialist and principal Extension agent for the Lower Eastern Shore of Maryland.
Since the last outbreak of H5N1 in 2015, Moyle and the UME team has incorporated biosecurity into nearly all their meetings with farmers. They’ve also produced training materials, including videos outlining the importance of such practices as changing shoes before entering chicken houses, showering immediately after working on the farm, limiting visitors and making sure service people wear full protective equipment on the farm.
The measures protect chickens from a range of diseases, but it’s nearly impossible to fully protect them from a disease like H5N1, which is spread by wild birds. That’s why alarm bells went off around the country when the recent strain of H5N1 started killing off wild birds that had never been affected before. Normally carried by water fowl, this bird flu was devastating raptors, owls, crows, vultures and many others. And it was much more deadly than previous outbreaks.
The arrival of this strain in the region sparked a series of Zoom calls with Maryland farmers and Extension agents, veterinarians and Department of Agriculture representatives, all sharing information about conditions on the ground and how to protect flocks from contact with wild birds and their feces.
“We had hundreds of people on some calls,” said Jennifer Rhodes, principal Extension agent for Queen Anne’s County, Maryland. “In addition to Extension agents, UMD has veterinarians like Nat Tablante who answer farmer questions that I can’t answer, and guide them on best practices.”
Rhodes said that when the outbreak started, she focused on anticipating farmers’ needs. “My biggest concern is for farmers' mental health,” she said. “I want to make sure they’re OK. You know you grow all these birds expecting them to go to market, and to have to lose them all like that, it’s hard. So, I want to make sure farmers understand the resources and programs available to help them recover losses if the virus spreads to their chickens.”
So far, although millions of birds have been culled in Maryland, the losses represent a small fraction of total poultry production in the state, and the region has managed to escape serious outbreaks.
“That’s good news, but it doesn’t mean we can let our guard down,” Moyle said. “Because it doesn’t look like this is going away.”
Principal Extension agents Jennifer Rhodes and Jonathan Moyle work closely with farmers to ensure Maryland’s poultry industry is prepared for threats like H5N1.
A suite of bio-security measures like disinfectant foot baths, and requiring farm visitors to wear personal protective equipment help prevent the spread of potential pathogens on and off of poultry farms.
According to Jennifer Mullinax, associate professor in AGNR’s Department of Environmental Science and Technology, Moyle’s prediction is dead on. Mullinax and her graduate student Johanna Harvey tracked the arrival and progression of H5N1 in North America and concluded that it is likely to become endemic, and slowing its spread will require unprecedented levels of coordination at regional and national scales.
“Our study is really a call to arms saying, we can’t afford to address this from our individual silos any more. Federal agencies, state agencies, the agriculture sector and wildlife management—we are all going to have to deal with this together.”
Mullinax, who teaches decision-making science said the research team recommends a specific management approach that brings people together from across disciplines and jurisdictions, and is much like dealing with a human pandemic.
“Good decision-making science is what you do when you don’t know what is going to happen next,”
Mullinax said. “This is a novel virus for North American birds, so no one knows if their immune systems will adapt, or how long that will take, or what that will look like. Where do we direct our funds for maximum benefit? Is it a vaccine? How do we track it in wild birds? Do we test the water or the soil? What are the triggers for different actions, and how do we measure if we’re succeeding? These decisions have to be made on multiple scales.”
One concern that has received a lot of attention is whether this H5N1 could evolve into the next human pandemic. Although sporadic H5N1 infections have appeared in people and other mammals, it has not evolved to spread easily between humans. But epidemiologists are keeping their eye on the risk of that changing.
One group of AGNR researchers is developing tools to study how the virus replicates and evolves in birds, and to identify the barriers that keep the disease from jumping species. Assistant professors Andrew Broadbent and Younggeon Jin from the Department of Animal and Avian Sciences are developing techniques to grow miniature, artificial airways and intestines from chicken and duck cells that can be used to study the virus without housing and infecting live birds.
“These organs are where new flu strains emerge,” Broadbent said. “But very little is known about how the virus interacts with them. So, having these organoids can help us study, for instance, where the most change occurs in the virus.” That can help guide surveillance efforts for example, by determining where to swab an infected animal for testing."
“Studying these things in wild animals is very difficult,” Younggeon said. “With these models, not only will we not need to infect live birds, but we will be able to ask questions we can’t ask now.”
Ultimately, the researchers hope to compare how the disease behaves in their lab-grown organoids with those from humans and pigs to begin tracing out similarities and differences and identifying barriers that so far have prevented the virus from jumping species.
The project is being sponsored in part by a $570,000 grant from the University’s Grand Challenge Program, which has dedicated $30M to supporting projects that address critical societal issues.
Over the coming years, whatever direction this virus takes, our team of researchers, veterinarians and Extension specialists will be working diligently to understand and prevent the disease and keep poultry farmers in business.
by Kimbra Cutlip : Momentum Magazine Summer 2023
