What is your assessment of the current situation with H5N1? Both in dairy cows in the U.S. and globally?
It’s very bad in both the U.S. and globally. In the U.S., the dairy cattle outbreak continues to spread and there is no current possibility for containment as long as we don’t know the full scale of the outbreak. Globally, it is not yet in cattle, but a panzootic (multi-species) outbreak has occurred since 2021 and continues to kill birds as well as spill over to other mammals and humans. There were two fatal cases this past week in southeast Asia. To minimize the risk of adaptation to humans, it is urgent that the cattle outbreak be controlled.
What could animal and health agencies in the U.S. and globally be doing better, and what are they getting right?
The U.S. agencies are responding as best as they can and it’s very good that they have taken measures like manufacturing almost five million doses of H5N1 vaccines (potentially for protecting dairy workers and vets at high risk), as well as implementing the Emergency Assistance for Livestock, Honeybees, and Farm-raised Fish Program (ELAP) to compensate dairy farmers for their losses. However, they don’t have sufficient resources or power to test as broadly as needed and there is not enough support from our elected officials (funding from Congress or the White House). Also, the federal agencies are not making enough of an effort to share data rapidly or granularly. For example, new sequence data is released sometimes weeks after it is obtained and there is not enough metadata (data about where and when the sample was collected, etc.) accompanying it to allow external researchers to perform extensive analysis. I want to be clear that this is not the scientists’ fault, nor the fault of the many officials working at these agencies, but structural issues with how these agencies operate. They are not designed for rapid responses or transparency, and it shows.
Finland will be vaccinating at-risk people like poultry farm workers this month; do you expect other nations to follow suit? Could the U.S.?
I hope that the U.S. does follow suit. I think it’s critically important to protect dairy workers and others who are at high occupational risk.
Does mRNA technology offer hope of increasing our capacity to create bird flu vaccines at scale?
Yes, although we are capable of producing flu vaccines at scale using existing methods. The bigger issue is funding the manufacturing and finding facilities to manufacture these vaccines without harming production of seasonal flu vaccines.
Are there any steps individuals can take to protect themselves? Should they be avoiding any food types – normal dairy milk or unpasteurized “raw milk”?
YES. Pasteurized milk is safe, but people should absolutely NOT consume raw milk.
How far off are we from bird flu becoming transmissible between humans, potentially sparking a pandemic? Is it possible it might never happen? How hard is it to predict?
There is not yet evidence that the virus can transmit efficiently between ferrets (a surrogate for humans) via the respiratory route. But that could change, especially if more human infections can occur. I always count on viruses to adapt to their hosts if they get enough practice. We need to contain the cattle outbreak now before that happens.
H5N1 historically has a fatality rate of around 50%, according to the World Health Organization. But the cases so far in the U.S. cattle outbreak have been mild. Can you explain what might be going on there?
We don’t know, but it’s possible this may be the route of infection or just differences between individuals. There have only been four cattle-associated cases, so it may just be that we haven’t seen a severe case … yet.
