There’s been a lot of discussion in the media recently about the possibility of an avian flu outbreak in humans. This is a breakdown of what we know so far, what we don’t know, and what steps you can take to prepare for an emergency.
Avian flu is a type of influenza A virus. In addition to the moniker “avian flu,” you have probably also seen the virus referred to as “H5N1.” The letters and numbers refer to two types of surface proteins present on the virus: hemagglutinin (H) and neuraminidase (N). These proteins are essential to the virus’s ability to infect host cells. Although avian influenza primarily infects birds, since the current outbreak began it has been circulating in a wide range of mammalian species. This is especially worrisome to scientists because when a virus infects a new host species, it may encounter other influenza viruses and swap genetic material. Through this process, a virus like H5N1 can acquire the ability to infect and spread among humans. Events like this are known as spillover events. Because H5N1 continues to infect a wide range of species–everything from sea lions to dairy cows–the chances of such a “swap” occurring are greatly increased. Avian flu has now spread to every corner of the globe, including Antarctica, and human efforts to stop the spread have been largely unsuccessful.
So far, a true spillover event has not occurred; the known human infections observed around the world, most recently in agricultural workers in the U.S., have been the result of animal to human transmission. But the recent detection of avian influenza in dairy cattle raises major red flags for public health officials for several reasons. While testing has confirmed that the meat and milk supply is safe, agricultural workers are a highly vulnerable, often undocumented population; they often lack access to basic health care and are often distrustful of authority figures due to having been scapegoated in the past. Although the CDC has attempted to provide incentives for testing, many of these workers are likely falling below the radar. This means that many infections are probably being missed, as workers fear a positive test result would mean being sent home without pay.
If a major outbreak starts in this population, it could quickly spread before authorities are able to act. Furthermore, there is relatively little that the federal government can do to force factory farms to cooperate with disease surveillance efforts. Currently, the USDA requires that dairy cows be tested for H5N1 before being moved across state lines. There are no requirements for workers to use personal protective equipment (and working conditions make using PPE very challenging), nor are their employers required to supply it. It is mandatory to report a positive H5N1 test, but it is not mandatory for workers to be tested. And while there are avian influenza vaccines for commercial flocks, there is no vaccine that is yet approved for use in cows.
Epidemiologists and public health officials have long worried about the impact of factory farming on pathogen spread. For example, twenty years ago the government of Thailand warned that large-scale agricultural operations were a much bigger threat to public health than small backyard flocks. Well before the concerns over H5N1, scientists have argued for a One Health approach to controlling disease outbreaks, which according to the CDC “recognizes that the health of people is closely connected to the health of animals and our shared environment.” Unfortunately, little progress has been made in the U.S. toward adopting this framework.
And perhaps most unfortunately, it seems that U.S. public health officials have learned little from their communications failures during the COVID-19 pandemic. Many mistakes are being repeated–failing to release new data in a timely manner, engaging in confusing “data dumps,” and releasing information without contextualizing it, to name a few. For example, the FDA, which is responsible for ensuring the safety of U.S. food, waited more than a month to issue a confusing press release stating the milk produced by American dairies is safe to drink as long as it is pasteurized and reassuring that there was no significant threat to the public–but also stating that milk from infected cows was being pulled from the supply. This press release also failed to address concerns from the public after viral particles were detected in some dairy products.
This type of inconsistency may seem minor, but it has already had consequences. The news that viral particles (which were shown to be non-infectious) were detected in the milk supply has not dissuaded some members of the public from drinking raw, unpasteurized milk–in fact, in states where its sale is legal, sales have actually increased. Even more worrying, there are now reports that some consumers are seeking out raw milk from infected cows, believing it will help build immunity to the virus. Setting aside concerns about H5N1, there are many reasons why you should avoid raw dairy products.
While there may not yet be a direct and immediate threat to humans who are not directly exposed to sick animals, there are steps we can all take now to protect ourselves. First and foremost, avoid any unpasteurized dairy products. Second, avoid raw or uncooked meat and dairy products in general, and this goes for your four-legged family members too. Trendy raw pet food diets are risky for both you and your pet. Given the added risk of H5N1, now would be a great time to switch your pet to an alternative diet if you are feeding them raw food. Lastly, don’t let cats or dogs spend time outside unsupervised. In particular, cats exposed to H5N1 on dairy farms have fared poorly, and cats are major killers of wild birds as well; while the risk of exposure to H5N1 may be quite low, there are still plenty of other reasons to keep your cats indoors.
The good news is that because avian influenza is a respiratory virus, the same strategies for personal protection that work against COVID-19 will work against H5N1. Eye shields, masks, hand sanitizers, and cleaning supplies are good investments. If possible, you may want to consider storing at least a week’s worth of shelf-stable food and toiletries (no need to hoard, however). Regardless of whether you end up using these supplies, it is good to keep a supply on hand in the event of any type of emergency.
Finally, share this information with friends and family, particularly those that may be vulnerable to misinformation. People respond best to people they know and trust. Provide resources where you can, and stay informed so that you can respond quickly if necessary.