Missouri health officials should be doing more on ‘perplexing’ bird flu case, experts say
Missouri officials are under growing pressure from public health experts across the country to pinpoint the source of the state’s first human bird flu infection. The experts say identifying the source would give invaluable insight into the disease’s potential to spread and become more dangerous to people.
But so far, while still investigating, the state has been reactive instead of proactive in its release of information about the case, experts argue.
It’s been roughly a month since officials with the Missouri Department of Health and Senior Services, or DHSS, detected the case through its flu surveillance program, which tests specimens from patients with influenza. The case, the 14th nationwide this year, was unique because the patient had no known recent exposure to livestock or other animals, which is how bird flu has spread to humans in the past.
The positive result surfaced through routine flu testing and tracking, not from a known outbreak related to sick cows or poultry like the other 13 cases in other states.
The state has released little to no details about the infected patient, who has recovered after being admitted to an undisclosed hospital for multiple days. State officials have cited a need to prioritize the confidentiality of the patient.
“There is no public health benefit to providing specific location information because there has been no evidence of human-to-human transmission despite following up with more than 100 individuals,” said Lisa Cox, a DHSS spokesperson. “Additionally, the release of the location is disrespectful to the patient’s privacy. Those who need to know have been in communication with public health officials.”
But knowing the location of the patient is important, particularly whether the person lives in a rural area or crowded city, said Amesh Adalja, an infectious disease doctor and senior scholar at the Johns Hopkins Center for Health Security.
“We don’t know how this patient got infected,” Adalja said. “But if we know that this person lives in the proximity of all the dairy cattle farms in Missouri, or poultry farms or swine farms or whatever it might be, that’s useful.”
The case has received scant attention among state lawmakers and politicians. But national health experts are watching Missouri closely, fearing the results of the investigation could show evidence of person-to-person transmission. That would be a sign indicating the virus, called H5N1, has the ability to readily spread among people.
Missouri’s case is “particularly perplexing and tantalizing,” said infectious disease expert William Schaffner, professor of preventive medicine at the Vanderbilt University School of Medicine in Nashville.
“If this H5N1 virus were to acquire that genetic capacity to readily affect people and to be readily transmitted from person to person, we might be on the threshold of not only a large national outbreak, but perhaps a global pandemic,” said Schaffner.
Those concerns appeared to ramp up last week when the U.S. Centers for Disease Control and Prevention announced that seven people who came into contact with the Missouri patient later showed symptoms of a respiratory illness, which may not necessarily indicate bird flu. Test results for those people are not yet available.
And while DHSS has been communicating with, and receiving assistance from, the CDC, the state has not invited the federal agency to investigate on the ground in Missouri — a move that some health experts have questioned.
Both the CDC and DHSS have said they believe the virus’ risk to the public remains low.
As of now, state officials have emphasized that the investigation is ongoing and that the agency has no evidence to suggest person-to-person transmission.
At the same time, the Missouri Department of Agriculture said it has no evidence that the patient was exposed to livestock.
That raises major questions about how the patient came in contact with the virus, and some health experts have questioned whether Missouri is doing enough to pinpoint its source. Fourteen states have reported outbreaks of the virus in cows, according to the CDC.
Missouri is not one of them.
Calls to test more cows, wastewater
Adalja said some health experts don’t believe that Missouri, which has a robust agricultural industry, does not have cattle that are infected with the virus. The state needs to integrate its health and agricultural agencies into the investigation to find the virus in its cattle, he said.
Massachusetts, for example, tested all 95 of its dairy farms for the virus and found no positive samples. The state touted itself as the only state in the nation that tested all of its dairy herds with 100% negative results.
“They seem to not want to find it in dairy cattle,” Adalja said of Missouri. “So I think knowing if this (patient) lives in a county where there is a lot of dairy cattle, that would be important to know.”
The Missouri Department of Agriculture has had minimal involvement in the investigation, said spokesperson Christi Miller. As of Sept. 30, the department has tested 84 lactating dairy cows before moving them to other locations in the state, and all of those cows tested negative for the virus. She said Missouri cows have not shown signs of being sick.
“There have been no tests of dairy cattle due to symptoms of avian influenza, as other states have experienced,” Miller said.
Dairy producers are constantly monitoring the health of cows and there have been no reports of symptoms from dairy owners or their veterinarians, said Miller. Those dairy producers can also test their cows at any time at the agency’s lab in Springfield or in the animal health lab at the University of Missouri-Columbia.
On top of concerns about dairy cattle, the state has also not asked Marc Johnson, a professor of Molecular Microbiology and Immunology at the University of Missouri-Columbia, to test wastewater for the H5N1 virus.
In 2021, Johnson’s lab detected the COVID-19 Delta variant in wastewater weeks before the state’s first case was reported, according to St. Louis TV station FOX2.
“We’re probably the first group in the country to set up a system for measuring H5 from wastewater, but the state has not asked for us to test for it yet, and we are not allowed to test for anything unless they ask us to,” he said. “At this point, we’re one of the only states that is not doing H5 specific tests.”
However, a map from the CDC’s wastewater program shows that one wastewater sample was tested in Jefferson County near St. Louis. That sample was negative for the bird flu.
When asked about concerns that Missouri wasn’t doing enough to find the source of the virus, Johnson said he thinks the state wants to know where the patient got it from.
“I don’t think it’s quite that nefarious, but…they’re not being particularly aggressive about wanting to see where H5 might be circulating,” he said.
‘A good investigation’
When asked about the investigation this week, Cox, the DHSS spokesperson, pushed back on concerns about person-to-person transmission. The positive case’s connection to the seven other people who had respiratory symptoms was being mischaracterized, she said.
“These individuals are certainly not considered cases,” she said. “There is not an active outbreak established to date. It has not been confirmed that any of the contacts had any type of flu, or COVID or another illness for that matter.”
State health officials are performing serology, or blood tests, to determine whether any of those people who were exposed have been infected with the bird flu, she said, emphasizing that no other cases had been detected.
“Those speaking to this investigation who have not been directly involved seem to be missing important context,” she said. “Based on what we know and what we do not know, this should not be mischaracterized as an H5 outbreak or a situation of person-to-person transmission.”
The agency is continuing to investigate and respond to the case along with local public health and clinical partners, as well as the CDC, Cox said.
“Relevant updates are being shared only as components of the follow-up are completed to avoid misinformation or confusion,” she said.
Cox also provided The Star with a lengthy update on the investigation, which included details on the agency’s contact investigations, blood tests and other flu surveillance work.
Adalja, with Johns Hopkins, said Cox provided a lot of good information in the update that was reassuring about the investigation. However, he criticized the state for being reactive in its release of information.
“A lot of us would have liked to have seen all of that been released proactively, not just because you push them,” he said. “Because a lot of us in the field have many questions, and… they could go a long way to answering those questions if they were proactive in releasing that information.”
The information DHSS provided to The Star was “clearly the most elaborate description” of the investigation he’s read, said Schaffner. The state’s response appears to be reasonable, but it could be more intensive, he said.
“It’s a good investigation. It’s very solid…this is a good Chevy, but it’s not a Cadillac,” Schaffner said.
A more intensive investigation would require more resources, and Schaffner said he would have invited the CDC in to investigate on the ground.
“I don’t want you to get the idea that it’s not a good, solid, reasonable investigation. And lots of people would say, ‘okay, yeah, that’s good enough,’” he said. “Others would say, given the potential import of this to general public health, they would have bought the Cadillac.”
This story was originally published October 2, 2024 at 2:15 PM.
