TRACKING EMERGING VIRUSES – July 16, 2025 – Bird Flu
“Bird flu remains a risk in the U.S., but we don’t know as much about its threat level because the CDC stopped conducting much surveillance some time ago. They never did the kind of studies some experts had wanted.”
“At the same time that we are cutting surveillance, some experts are concerned that Kennedy’s proposal to let bird flu spread through poultry could set us up for a pandemic. In fact, in this week’s Science, several argue that this “let ‘er rip” approach would be “dangerous and unethical.” Their concern is that by allowing the virus free rein, it will more likely spread and mutate, resulting in a pandemic. Gigi Gronvall, PhD, Johns Hopkins Center for Health Security, explains: “The thing that we are most concerned about is that H5N1 could reassort with a circulating flu virus and gain the ability to transmit between humans. Anything we could do to reduce that likelihood, we should be doing. That includes vaccinating people against what’s currently (influenza) circulating and also against H5N1.” (1)
“The Trump administration’s recent decision to cancel $766 million in funding to vaccine company Moderna for the development of a bird flu vaccine represents an ominous retreat from America’s pandemic preparedness….”
“The H5N1 bird flu presents no ordinary threat. During the past year, there have been scores of confirmed cases of symptomatic H5N1 bird flu in humans in 13 states, with one fatality.”
“The ability of the H5N1 virus to infect so many species of mammals is a particular concern because of the possibility that it could lead to the emergence of a new pandemic strain via a process called reassortment. That occurs when two different influenza viruses, like an avian H5N1 virus and a human seasonal flu virus, simultaneously infect the same host cell and exchange genetic material, creating a new virus with a mix of genes from both parent viruses. (The flu virus genome consists of eight segments of RNA, which can be swapped during coinfection.)
One potential outcome is a virus that retains the H5N1’s ability to cause severe illness but also acquires the ability to spread easily among humans, potentially leading to a pandemic. The 1957 and 1968 flu pandemics were caused by reassortment events where avian and human influenza viruses exchanged genes.” (2)
“Influenza hadn’t previously been known to infect cattle, much less cause the kind of infections in their udders that have now begun circulating in milking parlors across the country. The continued circulation of H5N1 in cows is one of the biggest concerns experts have about this flu subtype. Though H5N1 hasn’t yet spread human-to-human, people can catch the disease from cattle, mostly through close contact with infected milk. And the more it circulates in an animal that humans regularly interact with, the more chances the flu has to stumble on just the right mutation to leap to people and start adapting into something with pandemic potential.” (3)
Bird flu found to evolve rapidly, infecting more hosts and finding ways to spread more effectively, https://medicalxpress.com/news/2025-07-bird-flu-evolve-rapidly-infecting.html
UF scientists seek to curtail bird flu’s spread through education, outreach efforts, https://www.mainstreetdailynews.com/health/uf-bird-flu-education
“Rationalizing the lull in infections has been puzzling. Researchers have tied wild birds, the virus’s largest reservoir, and their spring and fall migrations to periods of greater spread of contagion. Cuts to staff who monitored the virus, at the U.S. Department of Agriculture and the Center for Veterinary Medicine, might also be playing a role. But these ideas dismiss the deeper and more fundamental problem around our present grasp of bird flu. As an infectious diseases physician who works primarily with immigrant populations, my perspective often sits at the nexus between the people a novel disease affects and the apparatuses that exist to control it. Lately, the actions of each arm of that equation, no longer motivated by the ethos of a collective concern, are fractured by individual ambitions and epitomize our faltering response.”
“Because infections are still largely constrained to animals and the marginalized people who work with them, bird flu has the distinction of being both omnipresent and barely visible. The way in which one country approaches it will, invariably, have rippling effects in others.
As the focus shifts to the economics of maintaining stocks of chickens and rebalancing the price of eggs, incentives for the testing of farmworkers remain inadequate, and protections among those who are foreign-born are, at best, dubious. From bench to barn, earnest collaborations with scientists and experts are also being undermined. Public health is a delicate concept. To uphold it involves a complex interplay between forces large and, more importantly, small. We can predict the risk of a bird flu pandemic from a single mutation in the virus’s genetic code. An individual, we must also realize, can upend things all the same.” (4)
1.CDC Bird Flu Response Cuts Could Lead To Another Pandemic, By Judy Stone, https://www.forbes.com/sites/judystone/2025/07/09/cdc-bird-flu-response-cuts-could-lead-to-another-pandemic/
2.Bird flu? Don’t worry, we fired the by Henry Miller, https://geneticliteracyproject.org/2025/07/15/bird-flu-dont-worry-we-fired-the-scientists/
3.What Would It Take for Bird Flu to Spread among Humans?, By Stephanie Pappas, https://www.scientificamerican.com/article/could-bird-flu-spread-between-humans-heres-what-it-would-take/
4. Opinion: What Happened to All the Human Bird Flu Cases?, By Arjun Sharma, https://undark.org/2025/07/10/opinion-bird-flu-emergency-end/
curated by Jonathan M. Metsch, Dr.P.H.
Clinical Professor of Environmental Medicine, Icahn School of Medicine at Mount Sinai