How prepared the U.S. is for a bird flu pandemic (2024)

Two candidate vaccine viruses — essentially the building blocks manufacturers use to produce a vaccine — appear well matched to protect against the H5N1 strain circulating among dairy cattle and birds, according to federal health officials. It’d probably be weeks to months before those shots could first be made available if needed, according to a Health and Human Services official who spoke on the condition of anonymity to describe an ongoing investigation.

Top officials at the Centers for Disease Control and Prevention said the agency is well poised to detect if a person has H5N1 through the agency’s regular surveillance for seasonal flu at more than 100 public health labs in all states as well as enhanced monitoring put in place in 2022 for anyone who has been exposed to birds infected with that strain.

“CDC and the whole U.S. government is taking this situation very seriously,” CDC Director Mandy Cohen said in an interview. “We had not seen avian flu in cattle prior to last week. That is new. It’s a reservoir for virus to circulate and potentially, change.”

The development underscores critical questions about whether the country is equipped to handle an influenza outbreak after the coronavirus pandemic, the worst global health crisis in a century, exposed the weaknesses in the nation’s public health infrastructure and decimated the public’s trust in key federal agencies.

More than half a dozen federal officials say their job is to prepare for the worst but said risk to the general public remains low. H5N1 was first identified in geese in China in 1996, but outbreaks in the past haven’t led to an explosion of cases in humans.

The heightened attention on bird flu comes after the virulent H5N1 strain was recently identified in U.S. dairy cattle for the first time. Federal and state officials announced Monday that a dairy worker in Texas is being treated for bird flu, marking the second-ever human case of this bird flu strain in the United States. The patient — who experienced eye inflammation as the only symptom — was exposed to cattle presumed to be infected with the virus. Disease trackers are monitoring for additional cases, particularly whether the virus can jump from human to human, which has happened infrequently and would be cause for more alarm.

“Why I feel we can say the risk of avian flu remains low to the public is because the virus we are seeing in the cattle and in this one human case is the same genetic virus that we were seeing in poultry,” Cohen said, meaning the virus has not yet evolved to spread easily in humans.

Since bird flu isn’t a novel virus, some experts believe the country is better prepared to tackle such an outbreak than covid, but cautioned against overconfidence.

“Federal funding for pandemic influenza has not kept up with the threat, even by the government’s own assessments,” Tom Daschle, former Senate majority leader and head of the Coalition To Stop Flu, which includes public health organizations and vaccine manufacturers, said in a statement Tuesday.

The government group responsible for defining requirements for medical countermeasures called for $1.15 billion in funding for pandemic influenza for 2025, Daschle said. But the $335 million in Biden’s 2025 budget request fell far short. (Congress appropriated $335 million for pandemic influenza preparedness in the most recent appropriations bill.)

Significant cuts to preparedness funding were also made two weeks ago in a bipartisan appropriations package, Daschle said. That funding could have been used to speed vaccine development and manufacturing, improve diagnostics and early warning capabilities, and ensure the public health workforce on the front lines is adequately resourced, he said.

Detecting changes in the virus’s pattern starts with surveillance.

When there is a presumptive positive test, state health departments begin an investigation and send specimens to the CDC for confirmatory testing, said Vivien Dugan, who heads the agency’s influenza division. The CDC conducts extensive lab testing and analysis to determine the risk to public health; it expects to finish sequencing the sample from the infected dairy worker this week.

Since bird flu outbreaks have become widespread globally in recent years, the CDC and the Agriculture Department have enhanced surveillance — closely monitoring anyone who has been exposed to infected birds or poultry infected with H5N1 for 10 days. More than 8,000 people have been monitored in all the 50 states, D.C., New York City, Puerto Rico, Virgin Islands and the Northern Marianas. Until this week, the only positive case was in Colorado in 2022.

If an outbreak in humans occurs, quickly scaling up vaccination would be paramount. The nation’s 10-year playbook to modernize flu vaccination sets a goal of delivering first doses of a vaccine within 12 weeks of the declaration of an influenza pandemic.

Federal officials point to some good news: Manufacturing a vaccine to match this specific strain of the virus and then mass producing it is vastly easier than the effort to develop a coronavirus vaccine. That’s because there are already vaccines to combat the bird flu. They can be altered, experts say, to better protect against this specific strain.

This scenario would probably only happen if there’s fairly widespread human-to-human transmission. But there would be trade-offs. Manufacturers have limited capacity to produce flu vaccine. Manufacturers are now in the midst of producing the estimated 156 million to 170 million doses of the annual seasonal flu vaccine to be given in the fall.

It would be a risky political decision to disrupt that production and switch to making millions of doses of a new shot, public health officials and experts have said.

“We have a n of 1,” said CDC’s Dugan, referring to the single human case.

“It’s a good news story that we have bulk vaccine in [a government stockpile] but I don’t think we should assume that all Americans will get jabs,” said another federal health official who spoke on the condition of anonymity because of an ongoing investigation.

Those who do become infected with bird flu could be treated with antiviral drugs the Food and Drug Administration has approved for the flu. Experts and officials said there haven’t been any signs that the current strain would be resistant to those therapeutics. The nation’s Strategic National Stockpile has an emergency supply of antivirals that are also available on the commercial market.

“In the wake of our experiences with covid-19, it has become increasingly clear that some individuals show a preference for therapeutic interventions post-infection over preventative vaccination,” Taylor Sexton, the executive director of the Medical Countermeasures Coalition, wrote in an email. “Vaccines and therapeutics are two sides of the same coin when we are fighting a pathogen, and both remain critical.”