The United States has vaccines for bird flu. Here’s why you can’t get one

Like bird flu The virus is spreading among birds and dairy cattle throughout the United States, and the state of Georgia became the latest state to discover the virus in commercial poultry flocks, and on Friday it suspended all poultry sales to the United States. Reducing the spread of the disease further. Nationally, egg prices are rising, if you can find them at all in your local grocery store.

The ongoing outbreak of disease in animals has also led to… At least 67 human cases of bird fluAll but one of them cause mild illness. Earlier this month, someone in Louisiana He died after being hospitalized due to severe bird flu In December. It is the country’s first recorded death attributed to the H5N1 virus.

The United States has previously licensed three H5N1 vaccines for use in humans, but they are not commercially available. The government has purchased millions of doses for the national stockpile in case they are needed. But even as the outbreak spread, federal health officials under President Joe Biden have been reluctant to deploy them. Experts say the decision came down to risk, and for now, the risk of contracting the H5N1 virus remains low. Rolling out a vaccine to farmworkers and other people most at risk of infection would be a more targeted tactic, but even that action may be premature. Now, with an impending change in federal health leadership as President Donald Trump begins his second term, the decision rests with the new administration.

“Right now, from the standpoint of severity of infection and ease of transmission, it does not seem necessary to produce a vaccine to protect humans,” says William Schaffner, MD, a professor of preventive medicine at Vanderbilt University in Tennessee. .

So far, no person-to-person spread of H5N1 has been identified, but health officials are monitoring the virus for any genetic changes that would make transmission between people more likely. Most cases of bird flu are associated with exposure to animals. Of the 67 known human cases in the United States, 40 have been linked to sick dairy cattle and 23 have been linked to poultry farms and culls. In the other four cases, the exact source is unknown.

In the United States, human cases have been mild, with many causing only conjunctivitis. In some cases, people experience mild respiratory symptoms. Aside from the Louisiana patient, all individuals who tested positive for H5N1 recovered quickly and never required hospitalization. However, historically, H5N1 has been fatal in about 50 percent of cases. Since 2003, a total of 954 cases of human H5N1 infection have been recorded The World Health Organization has reported, About half of them died. Egypt, Indonesia, Vietnam, Cambodia and China have reported the highest number of human deaths from bird flu.

These numbers come with some caveats. First, many of these deaths occurred in places where people lived near sick poultry. “In those circumstances, it is thought that they probably got a very large dose of the virus,” Schaffner says.

In addition, the case fatality rate — the proportion of infected people who die from the disease — takes into account only known cases, and some cases of H5N1 go undetected in part because the symptoms of bird flu resemble other respiratory viruses. In the United States, language barriers among farmworkers, lack of testing, and workers’ reluctance to report illness are also factors. “We are probably missing more cases than we are detecting, and we are more likely to detect a serious case,” says Shira Doron, chief infection control officer at Tufts Hospital in Boston and an epidemiologist at Tufts Medical Center Hospital.