Scientists say novel bird flu requires urgent coordinated response

The team found that the deadly impact on wild birds and the shift from seasonal to year-round infections signal dangerous changes in bird flu in the United States. They concluded that there is an urgent need for unprecedented national and regional coordination to manage the spread of a disease across jurisdictions and disciplines. The team also suggests that H5N1 will likely become endemic, potentially posing risks to food security and the economy.

The article was published on April 19, 2023 in the journal Conservation Biology.

“We’ve been dealing with low pathogenic avian influenza for decades in the poultry industry, but this is different.” said Jennifer Mullinax, an assistant professor in UMD’s Department of Environmental Science and Technology and co-author of the study. The low pathogenic disease is less contagious and easier to contain than the highly pathogenic variety.

“This highly pathogenic virus is wiping out everything in numbers we’ve never seen before,” Mullinax said. “This document illustrates how unprecedented this is and outlines what we believe is happening. It is truly a call to arms that we cannot afford to address this issue from our individual silos. Federal agencies, state agencies, agriculture and wildlife management, we’re all going to have to deal with this together because we can’t afford not to.”

The team’s findings are based on an analysis of five different data sources that provide information on the incidence of highly pathogenic avian influenza in wild birds and poultry with a focus on the United States and Canada as well than on a global database from 2014 to early 2023.

Data shows the progression of highly pathogenic H5N1 as it spread from Eurasia to the United States where it was first documented in late 2021. As of October 2022, the disease had resulted in 31 wild bird deaths reported, representing approximately 33,504 wild bird detections. in the United States and Canada. In addition, more than 58 million domestic poultry have been infected or had to be culled to limit the spread of infection in the United States and 7 million in Canada.

In 2015, an outbreak of highly pathogenic H5N8 in the United States resulted in the culling of 50 million poultry. But the disease was eradicated from North America the same year, largely because it had no serious impact on wild birds, making containment through culling of poultry relatively easy. But H5N1 poses new challenges.

“Unlike H5N8, this disease strongly affects wild birds,” said Johanna Harvey, postdoctoral researcher at UMD and lead author of the study. “It is difficult to estimate how many birds are truly affected in wild populations, but we are seeing dramatic effects of the disease on raptors, seabirds and colonial breeding birds. a worst-case scenario.”

The data also reveals a shift from a seasonal disease to one that occurs year-round. Previous outbreaks of bird flu – whether it was a low pathogenic virus endemic to the United States or the highly pathogenic H5N8 in 2015 – usually occurred in the fall, which meant that farmers could prepare for the seasonal epidemics, slaughter herds to stop the spread of disease, and have almost a full year to recoup their losses. But this new virus appears to be sustained throughout the year, with summer disease detections in wild birds and outbreaks in poultry occurring in the spring and fall.

Although declaring an endemic disease is a complicated process, the study authors suggest that the United States will likely follow the patterns seen in Europe where highly pathogenic avian influenza is already treated as an endemic disease rather than something that can be eradicated.

The research team recommends a management approach based on a method called structured decision-making, which follows a specific process of identifying and bringing together relevant individuals with an interest, expertise or stake in an issue, distinguishing the unknown factors and establishing measurable measures. objectives and actions with quantifiable results. The process is very much like a human pandemic.

“Good decision science is what you do when you don’t know what’s going to happen next,” said Mullinax, who teaches decision science. “This is a new virus for North American birds, so no one knows if their immune systems will adapt, or how long it will take, or what it will look like. Where are we directing our funds for a 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 are successful? These decisions need to be taken at several scales.

The document outlines examples of potential triggers for action, identifying the relevant decision makers needed to coordinate a response and some of the challenges that may arise. The researchers hope their work will bring key players to the table to consider next steps.