With the warmer weather and the retreat of flu and COVID as major risks for this spring season, you may think you’re in the clear now. However, it would be foolish to put your head in the sand when it comes to other possible looming health threats, in particular, bird flu or avian flu. Let’s take a look at a few data points so that you can put this public health threat in perspective.  The avian flu virus has killed millions of birds on every continent around the world except Australia, and has spread to a diverse range of mammals, including cats, goats, dolphins, and, in the United States, cows. While it’s been around in some form for several decades, its spread to mammals is more recent, and there are documented cases of it being spread to humans, with even a few deaths in humans recorded in the US, though no cases yet confirming human-to-human infection. Most spread to humans has occurred among farmworkers. Of the hundreds of human cases recorded around the world, the mortality rate has been close to 50% of those hospitalized. However, most recorded human cases in the US tend to have more mild symptoms, including conjunctivitis, respiratory and stomach upset, runny nose, and sore throat. More serious symptoms can include shortness of breath and difficulty breathing. It’s not yet clear what puts you at risk, and there is some suggestion that older adults, having already been exposed to older flu strains, may be less at risk than young children. Currently, you’re most likely at risk through contact with infected birds or mammals, or by ingesting undercooked meat or consuming raw milk or cheese made from raw milk. It’s believed that the avian flu virus can survive in raw milk cheese for several months.

Given the limited spread to humans to date, is there a reason the general public should worry at this point? It’s clear that the avian flu virus has mutated, and in recent years, a new subtype has emerged, spreading from wild birds to domestic poultry to wild mammals and now to cats and cows. The transmission to cows was unexpected, and the infection of cats has been documented as coming from humans, thereby suggesting that humans can transmit this virus. Commercial labs can test humans for bird flu, and vaccines have been developed, but they have not been matched for the current strain of bird flu, so it’s not clear how effective they would be. While domestic poultry and other mammals could be vaccinated, to date, that has not been done, as our international trading partners (who buy a lot of domestic poultry from the US) would not be willing to purchase vaccinated poultry.

What are the chances that this bird flu will begin to spread from human to human and potentially cause another pandemic of the magnitude of COVID? The risk is not zero, and, in fact, many experts now have serious concerns that we may be facing a public health emergency in the future. As one expert made clear, “I think we are living next to a volcano and it may erupt or it may not. But we need to prepare for the possibility of a pandemic.” Currently, the virus is following a common pattern found in viruses of “stepwise invasion” from animal to human, in a way that could then transform into human-to-human transmission. We can perhaps slow down this spread through such measures as better care for food-bred birds and animals, better vaccination for seasonal influenza (which would lessen the likelihood of the avian flu mixing with our usual seasonal influenza), and we can improve the nutrition and sanitation of poor populations around the world. However, none of these efforts will ultimately stop the spread from human to human if that is our inevitable path. In fact, some experts paint a dire picture, given how the virus has already spread, coupled with the chaos and budget and staff cuts that are now plaguing our public health and health research infrastructure. As one expert has said, “We’re given a stick, and they put a blindfold on us, and we’re sent into a gunfight, and we’re losing. We are losing.” Currently, there are not sufficient “boots on the ground” to collect transmission data, millions of birds have had to be killed, and funding efforts have been paused on new vaccine work. Furthermore, many farm workers are undocumented immigrants who will hesitate to come forward to be tested due to the current political climate, at a time when more than 450 different mammals have been infected. Another expert warned, “If this should spiral into a pandemic, this flu could make COVID look like a walk in the park.”

Unfortunately, however, the general public, already skittish about public health measures due to the mistrust sown during the COVID pandemic, is not sufficiently aware or concerned about this growing threat. A recent study in the American Journal of Public Health reports that the public is both ignorant and apathetic when it comes to concern about bird flu, which will be a real obstacle if the virus begins human-to-human transmission. Many are ill-informed about such basic food safety practices as drinking only pasteurized milk and cooking meats at a high temperature to kill any virus. Furthermore, the study found that only ¼ of the people surveyed knew that the bird flu virus could be transmitted to people, and less than 20% of respondents were aware that cattle have now been infected. So, the question is whether the public at large will have the willingness and enthusiasm to do what’s necessary if we face a large-scale pandemic caused by the avian flu. While that remains to be seen, the threat from bird flu is no longer in question.