- The Department of Health and Human Services (HHS) cut funding to Moderna’s pandemic preparedness program, which develops vaccines for influenza strains like bird flu.
- Millions of birds in U.S. poultry farms and some cattle herds have been affected by bird flu, but the overall risk to humans remains low as no human-to-human transmission has been reported.
- Still, recent research shows the bird flu virus may be just a few mutations away from transmitting more readily to humans, which could elevate risk.
The Trump administration canceled a $766 million contract to develop a bird flu vaccine with Moderna, the drug manufacturer announced on May 28.
The plans to develop an mRNA vaccine to protect people against flu strains that could lead to pandemics were canceled by the Department of Health and Human Services (HHS) over safety concerns about the technology, Reuters reports.
Despite the promising results of Moderna’s pre-pandemic influenza vaccine’s effectiveness in a Phase 1/2 clinical study, the cancellation of the program sows “uncertainty,” Stéphane Bancel, Moderna’s Chief Executive Officer, said in a statement.
“These clinical data in pandemic influenza underscore the critical role mRNA technology has played as a countermeasure to emerging health threats,” Bancel continued.
As the H5 bird flu virus continues to spread among U.S. dairy cow herds and poultry farms, the overall risk to humans remains low.
For context, bird flu has affected more than
Earlier this year, a
Like any respiratory virus, bird flu is constantly mutating. This is evident in the recent rise in the number of domestic cats and other wild animals that have contracted the virus. Compared to humans, the mortality risk for some animals is much higher.
Still, according to recent research, bird flu could be just a few mutations away (or less) from transmitting more readily to (and among) humans.
To learn more about the bird flu outbreak, Healthline spoke with William Schaffner, MD, professor of preventive medicine and infectious diseases in the Department of Health Policy at Vanderbilt University Medical Center in Nashville, to find out just how worried we should be about the virus and what can be done to minimize any risk.
Schaffner: There may well be some silent spread. Public health Investigators spoke with these veterinarians about trying to find any potential contact with an animal known to be infected, but the veterinarians may have had contact with many animals, not all of whom had been tested, so they could have acquired their infection in that fashion.
This doesn’t necessarily imply person-to-person spread but spread from an undefined animal source. I think that is the more likely way these veterinarians became infected, whether it’s a veterinarian or a farm worker contracting the virus from an unknown source. Maybe it’s poultry, maybe it’s livestock or cattle.
Schaffner: Yes, indeed — very, very low. There still is no evidence of easy person-to-person spread. In fact, I don’t think we have any evidence that any of the cases documented in the United States spread their infection to another close contact. So, this virus still has not acquired the genetic capacity to spread readily from person to person.
If it should develop that capacity, we might well be on the threshold of another pandemic. These pandemic influenza viruses in the human population occur every 10 to 20 years, but this has not happened yet with this bird flu virus, which, in its previous forms, has changed over time and has been circulating in the wild bird population and in domestic poultry for about 20 years.
But I’m not diminishing the fact that it has gotten into mammalian species, most prominently dairy cattle, but also mink cats, domestic cats, and even in certain zoos in other mammalian species. So there is concern, clearly.
In the public health and infectious disease community, influenza-like illnesses are being sampled, and molecular fingerprinting of these viruses is being done. It’s like our radar system, picking up the earliest possible indication that this virus may have changed to become more dangerous to the human population.
Schaffner: I’m afraid I can’t reassure you a whole lot. There are two ways this bird flu virus could acquire mutations that allow it to be transmitted readily to humans and from humans to humans.
First, these viruses multiply constantly in wild birds, poultry, dairy cattle, and perhaps other mammalian species by millions and trillions of times. So they’re multiplying all the time, and, by chance alone, such a mutation could occur.
This is less likely than the other way these pandemic influenza viruses have transitioned from birds to humans. Some animals can be infected both with the bird flu virus and with the human flu; they’re biologically able to do that. That animal, notoriously, is the pig.
Back in 2009, we had swine flu because that virus came via the pig from birds. An individual pig can become infected with the bird flu virus but also simultaneously infected with a human flu virus. These two viruses multiply in the pig simultaneously. They can trade genes. The bird flu virus could pick up from the human virus the ability to infect humans readily, known as reassortment. In other words, the genes are reassorted and trade genetic elements.
That’s the more common way for these new pandemic viruses to appear on the global scene, and we can’t tell you whether or when this will happen. It can happen next Tuesday. It can happen 10 years from now or not. This bird flu virus hasn’t done that yet, so what we can do is do surveillance. We set up this diagnostic radar system looking at these influenza viruses all over the world constantly, and now we have the scientific capacity to do their molecular fingerprinting so we can look at their genes. We couldn’t do that readily 15 or 10 years ago.
Schaffner: Domestic cats can be infected with bird flu, which causes serious illness. That’s been well established. It was quickly determined that was the case with barnyard cats around dairy cows. They consumed contaminated milk and became ill.
I don’t think we’re seeing cats infected in a backyard bird feeder or bird bath, but could it happen? Yes.
Depending upon your level of concern, I would say to use disposable gloves as you handle your bird feeder and your bird bath. When you come into the house, discard those gloves and wash your hands thoroughly. If you have a household cat and you’re concerned, taking down your bird feeder for the time being is a simple thing you can do.
Schaffner: If your pet cat gets bird flu, it’s pretty unlikely you could catch bird flu from your cat.
But as with any sick animal, I would be careful when handling it, particularly if it has an infectious illness. Listen to your veterinarian and wear gloves while you’re trying to comfort the animal.
Editor’s note: Now that plans for a bird flu vaccine are paused, it’s unclear whether production will resume and when. Moderna states it will “explore alternatives for late-stage development and manufacturing of the H5 program” consistent with the company’s commitment to pandemic preparedness.
Schaffner: There is already a blueprint or template for making a bird flu vaccine. It was made several years ago, and the United States stockpiled a certain amount of vaccine as a starter in case we had to use it.
Since the virus has changed a little bit over time, we’re now updating that vaccine, and we’ll have at least a starter amount in the national stockpile to be used In high risk populations, should that become necessary.
We’re working on vaccines for both humans and animals. Since bird flu is not an immediate threat to humans, there are no current plans to implement it. Looking ahead, it would probably be targeted first at people who work with poultry and dairy cows because they’re likely at the greatest risk. That would be just the start before we roll out a more comprehensive vaccination program if we thought a pandemic was starting.
As with all influenza vaccines, they do best in preventing serious disease. They cannot prevent every infection. You can’t prevent epidemics or pandemics, but you can minimize their serious impact and reduce hospitalizations and deaths.
As the CDC likes to say about the influenza vaccine, it turns wild into mild, to make the point that it reduces the severity of the illness rather than being able to prevent each and every illness.
Schaffner: We can’t predict the future. In its various variants, this bird flu has been around for 20 years, and it hasn’t happened yet. I will say there will be another influenza pandemic sometime. Will it be bird flu or another? Another bird flu or swine flu? We can’t say. When will it happen? Nobody knows.
You have to be prepared on the public health side, which takes resources. You have to keep your guard up and have a response capacity; sometimes, we lose track of that when we think about infectious diseases, influenza included.
We’ve been concerned about bird flu as a potential problem, but we’re also in the middle of a very large seasonal influenza outbreak, and the acceptance of the seasonal influenza vaccine has been much less than we would like.
My message to the public is, next fall, in preparation for the next flu outbreak, please make a resolution to get vaccinated and bring your entire family along to be vaccinated. That will blunt the impact of the next influenza outbreak because we will have another influenza outbreak next winter. I don’t know whether mild, moderate, or severe, but we’re going to have one.
A bird flu vaccine for poultry is underway, and experts say an updated vaccine for humans will be available should the outbreak ever reach pandemic-level concern.