Even as the H5N1 virus evolves, gaps remain in the nation’s contingency plans for human testing, scientists say.

New York Times – July 17, 2024 – The first step in combating any infectious disease outbreak is detection. Without widespread testing, health officials have little sense of who is infected, when to treat patients and how to monitor their close contacts.

In that sense, the bird flu outbreak plaguing the nation’s dairy farms is spreading virtually unobserved. As of Monday, the virus had infected 157 herds in 13 states. But while officials have tested thousands of cows and are monitoring hundreds of farmworkers, only about 60 people in the United States have been tested for bird flu.

Officials do not have the authority to compel workers to get tested, and there is no way for workers to test themselves. In the current outbreak, just four dairy workers and five poultry workers have tested positive for H5N1, the bird flu virus, but experts believe that many more have been infected.

The Covid-19 pandemic and the mpox (formerly monkeypox) outbreak in 2022 revealed deep fissures in the U.S. approach to testing for emerging pathogens. Those failures prompted federal agencies to move toward policies that would allow rapid scaling of testing during an outbreak.

But progress has been sluggish, interviews with more than a dozen academic and government experts suggest.
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Federal officials said that the number of tests at hand was more than adequate. But the tests that can pinpoint H5N1 are again available only at public health labs. Most clinics have tests for influenza generally, but they must send samples to one of the labs or to the C.D.C. to confirm infection with bird flu in particular.
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Federal officials have repeatedly said that H5N1’s risk to the general public is low. But the virus has adapted to new hosts at an alarming pace. It may yet mutate to spread among people, some experts have warned. If that were to happen, the nation would need tests not just in public health labs, but in homes, schools, workplaces and wherever else people might need speedy answers.

That requires federal officials to rapidly scale up by helping academic, commercial and hospital labs develop, manufacture and distribute tests. As the pandemic receded, several independent teams of experts called on the C.D.C. to establish flexible partnerships with commercial manufacturers that would begin at the first signs of an outbreak. The manufacturers would be asked to allocate production capacity to bird flu tests as soon as needed.

Bureaucracy and lack of funding may have hobbled progress. The C.D.C. has been discussing tests for H5N1 with 15 companies since last year. Eight have signed licenses to adapt the agency’s test. None of them have released a test yet.

The C.D.C. has “started having very preliminary conversations” about the technology, and the sensitivity and the specificity required for rapid tests, said Dr. Nirav Shah, the agency’s principal deputy director.[…]But other experts said that strategy was based on a series of assumptions.

For it to work, farmworkers must know about their risk of H5N1, recognize the symptoms, get to a clinic with an affordable consultation fee and be comfortable having their employer potentially find out the results, said Bethany Alcauter, the director of research and public health programs at the National Center for Farmworker Health.

“We have heard from many sources that there’s herds that are infected where public health agencies aren’t necessarily monitoring the workers, for a variety of reasons,” she said. “Workers aren’t getting any education in those situations, and they’re definitely not getting any testing.”

Six dairy workers in four states, including four from counties with infected herds, recently told Dr. Alcauter they had never heard of the bird flu virus.

The federal strategy also presumes that clinicians, even those in remote areas where dairy farms tend to be, would think to test for flu after the flu season has ended, are familiar with the procedure to send samples to public health labs and have the time to do so.

Distributing rapid tests to farmworkers and the organizations they trust can circumvent all these potential hurdles, Dr. Alcauter said: “The fewer steps in the process, the fewer chances for it to break down.”