Three months after the first detection of bird flu in US dairy cows, experts are expressing growing concern about the government’s response and the potential for a deadly pandemic.
Since avian influenza A (H5N1), also known as “bird flu”, was for the first time detected in dairy cows on March 25, the number of infected herds continues to rise.
To date, three human cases have been confirmed, and at least 118 dairy herds across 12 states have been affected since March. However, according to the Centers for Disease Control and Prevention (CDC)’s latest update on June 21, only 51 people have been tested, while an additional 690 individuals are under monitoring.
“Unfortunately, our response to H5N1 has taken too long,” Tom Frieden, former director of the CDC and current president and CEO of Resolve to Save Lives, told China Daily.
Frieden referenced the “7-1-7” target, a metric proposed by his organization in early 2020 and now adopted by other countries to gauge the effectiveness of outbreak responses.
This target calls for seven days to detect a suspected outbreak, one day to notify public health authorities, and seven days to complete the initial response.
“In the US, instead of seven days, the time from emergence of H5N1 in cattle to detection was more like 100 days, and it’s not clear the US met the seven-day target for initial response even months into the outbreak,” Frieden said.
While the US has taken steps like increasing test production, evaluating vaccines and tracking wastewater, Frieden stressed that more needs to be done to improve preparedness.
He pointed to the “rocky” relationships between government agencies due to differing priorities, legal authorities and political considerations.
“To meet the 7-1-7 target, we need communication and public health measures in the affected communities — and better connection between human and animal health. Any directives from the government should be crafted to the specific needs of each community,” he added.
Insufficient testing and tracking have left the US in the dark about the extent of the virus’ spread among animals and humans. Frieden attributed that partly to low trust in the government, particularly among rural Americans who are at the forefront of the outbreaks.
Jennifer Nuzzo, an epidemiologist and director of the Pandemic Center at Brown University’s School of Public Health, echoed this concern.
“Of great concern is that surveillance and response to infections on dairy farms is largely voluntary. Testing on farms is not systematic or fast enough to protect workers before they are exposed to infected cattle. In some states, health officials have been unable to get access to farms to monitor workers and investigate how the virus is spreading,” she wrote in an article published by The New York Times last week.
The US Department of Agriculture (USDA) has allocated $824 million in new funding to protect dairy cattle and introduced a voluntary “dairy herd status program”, which requires weekly testing. However, only six herds have enrolled thus far.
Rick Bright, former director of the Biomedical Advanced Research and Development Authority, told PBS that a significant portion of the dairy farm workforce consists of undocumented immigrants, who are wary of being tracked or traced by the government.
Bright further explained that farmers are reluctant to participate in government programs because if federal or state authorities discover a widespread outbreak on their farms, they risk shutdowns, loss of workforce and income.
“It’s really hard for us to know how many people have been exposed, and if there really is any human-to-human transmission or not,” Bright said.
In humans, the H5N1 virus causes lower respiratory infections leading to fever, cough, shortness of breath and pneumonia. It is considerably more deadly than seasonal flu strains, according to the 2024 report Epidemics That Didn’t Happen by Resolve to Save Lives.
“No one knows whether H5N1, if left unchecked, will become the deadly pandemic that public health experts like me worry it could,” Nuzzo wrote in her article. She warned that the virus could mutate to infect people more easily, and a highly contagious version could trigger a new pandemic due to the lack of immunity in humans.
Frieden shared those concerns, stating that the spillover of H5N1 into cattle raises the question of whether the virus can be stopped from becoming endemic in this new species. He acknowledged that this may be inevitable given the close contact between humans and cows.
“That said, the only thing predictable about flu is that it’s unpredictable. While we can’t predict the future, we should be preparing as best we can. That means tracking what’s happening in as close to real time as possible so we can respond in as real time as possible,” said Frieden.