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By Liv Osby

One person dead, millions of chickens destroyed and a spread to cats and other animals has renewed concerns among some experts about bird flu.

“So far, most people that have gotten a strain of bird flu … get conjunctivitis and some mild respiratory symptoms,” said Dr. Georges Benjamin, executive director of the American Public Health Association. 

“But it has enormous potential to mutate to a form that is very dangerous.”

Bird flu is widespread around the world resulting in outbreaks in poultry and U.S. dairy cows, as well as cases in people who work in those industries, according to the U.S. Centers for Disease Control and Prevention. 

There is no evidence of person-to-person spread so far, the agency reports, noting that the one person who died was exposed from a backyard flock. 

But the commercial poultry industry has been hit hard with many millions of chickens being culled to prevent the spread of the virus resulting in a nationwide shortage of eggs and spiking prices.

And bird flu has been found in several other species, including cows, domestic and wild cats, raccoons, foxes, and bears, experts say.  

“Almost 15 years ago, we were all very nervous about bird flu. But it never mutated and kind of died out,” said Benjamin. 

“But now it’s come back, and the concerning part is that it’s infecting so many other species,” he said. “And when this flu goes from birds into other species, like pigs … it becomes more infectious to people.” 

“We don’t live in little silos,” said Dr. Scott Curry, Assistant Professor of Medicine at the Medical University of South Carolina with the Division of Infectious Diseases. “Viruses mix and match in all different species.”  

“The risk of a mutation … is where our concern comes in for humans,” adds Dr. Linda Bell, state epidemiologist with the SC Department of Public Health. 

“At this time there is no evidence it’s being transmitted from person to person,” she said. “But if people who are infected with seasonal flu are also infected with bird flu, there can occur a genetic mutation that can result in a new virus that is transmitted from person to person.”

Particularly concerning is the case of a 13-year-old Canadian girl with asthma who became seriously ill with bird flu requiring intubation for several weeks and dialysis, said Dr. Helmut Albrecht, Medical Director of the Center of Infectious Diseases Research and Policy at Prisma Health and the University of South Carolina, noting that human deaths from bird flu have occurred in other countries for years.

While the girl survived, the source of her exposure hasn’t been found, he said, adding that the strain she had is mostly seen in wild birds in that area.

“It also had adaptations to being better prepared for mammals and humans,” he said.

“The strain they found in this individual … has been shown to be more capable of infecting people,” said Benjamin. “The good news is that it didn’t. So far.”

In South Carolina, there have been no reported cases of bird flu in people, Bell said, adding that DPH is following CDC guidelines for enhanced surveillance including testing patients hospitalized with flu to see what kind they have and taking appropriate measures to make sure it doesn’t spread.

CDC says the current risk to public health is low and adds it is keeping a careful eye on the situation “working with states to monitor people with animal exposures.”

Just 67 cases have been reported in people as of Jan. 27, according to the CDC. 

But with most cases being mild, and many workers in these industries being undocumented, it’s a good bet that’s an undercount, experts said.

“I can assure you we have more cases than we know about,” said Benjamin. “Most cases are mild and ... are not reported. Even in areas where there have been outbreaks in dairy cows, we knew we were missing cases in people.” 

“‘It appears that avian influenza is just as often as not a mild illness,” said Curry. “It’s easy to imagine it is in thousands … of farm workers. And the more of those (human infections) we have, the more we’re rolling the dice.”

Albrecht said the cases reported so far are “probably the tip of the iceberg.”  

“We found these cases not because they presented as severe, but because the system included agriculture,” he said, “… that’s where we have the surveillance.” 

But how accurate that system is, is anyone’s guess, he said, “because we don’t know how many patients with mild disease don’t show up.”

For example, Albrecht said, undocumented farm workers may not come forward fearing deportation.

“Are you going to risk that with pink eye and sniffles?” he said. “Obviously that’s a concern that one could have.”

Nonetheless, he said, farm owners should make their employees aware they are at risk.  

Bird flu was found in South Carolina in 2021 in samples from wild birds – including waterfowl like geese, ducks, and shore birds as well as birds of prey like vultures and hawks that feed on dead birds, said Dr. Michael Neault, state veterinarian headquartered at Clemson University. Since then, it’s been found throughout the U.S. in wild birds and has flared up now and then, he said. 

“We’re in one of those situations now where cases are flaring up across the country,” he said. “Since 2022, there are well over 108 million birds – commercial and backyard – that had to be culled out.”

While commercial flocks have been culled in Georgia and North Carolina, that hasn’t happened in South Carolina yet, said Julie Helm, director of the state Poultry Health Program.

“But it is a matter of when,” she said. “We knew this was going to be a high-risk season based on the number of birds flying down last fall from Canada and it infecting so many other species. A couple states not impacted before are now having huge flocks being culled.”

There are more than 4,300 poultry farms in the state, some 750 of them large commercial operations with up to 4 million birds, Helm said.

On the other hand, backyard flocks in the state have been affected. 

A mixed flock of pheasants, quail, and ducks in Spartanburg County tested positive around Christmas and had to be euthanized, Neault said.  

“The birds are dying anyway, they get so sick,” said Helm, “So we do have to depopulate affected flocks so it doesn’t spread to other farms.”

Backyard flock owners should follow steps to prevent infection of their birds, such as ensuring poultry is separated from wild birds, she said. Some also have clothing and shoes only worn around farm birds to prevent accidental contamination, she said. 

“Viruses mutate all the time, even among birds. And we’re always concerned about what can happen,” Neault said. “The USDA and CDC and state public health and us are all watching this very closely.”

While there are no state laws regarding backyard flocks, the commercial poultry industry has its own standards around feeding, testing and more, Neault said. 

And there’s a national disease surveillance program required for commercial farms to reduce the spread of disease, Helm said, adding that veterinarians are required to notify authorities within 48 hours of a positive test.

Clemson Extension also shares information and biosecurity alerts to producers and backyard flock owners, Neault said.

While vaccination of flocks has been discussed for years, it’s impractical and hard to do, they said.   

Neault and Helm say that birdfeeders aren’t a risk because the virus is not typically found the birds that visit most yards. 

But they say that anyone who finds a dead bird should wear gloves and a mask, use a shovel to pick it up, and bury it in the woods or double-bag it and put it in the trash.

And experts advise people not to eat or drink unpasteurized products, or feed their pets raw food or milk either, because the virus can spread to pets that way.

Meanwhile, the DPH is also getting information to health care providers, farmers and others as part of its public health measures, Bell said, noting there is guidance for poultry and dairy workers to protect them against exposure, including wearing masks.

The state is always monitoring for the emergence of novel infectious diseases, Bell said, adding that early mitigation and containment measures are important to control them when the numbers are small.

“Because once we get efficient transmission from person to person, as we’ve all seen, it becomes so much more difficult to control,” she said. “If we were to have the emergence of a novel virus, we might be looking at something similar to Covid, which would be the worst-case scenario.” 

The foundation of state preparedness is surveillance to identify cases and taking appropriate control measures, Bell said. 

So, patients hospitalized with flu are tested quickly to see if it’s the seasonal variety, Albrecht said, and if it’s not, further testing is done to see whether it’s bird flu.

Rapid home tests for bird flu are not yet available, he said, but he expects they will be at some point.

Meanwhile, people should avoid contact with animals and stay home if they get sick to avoid exposing others, Bell said, adding that people should also get vaccinated against the flu and use proper hand hygiene.

Curry adds that the nation is at a record low for seasonal flu and Covid vaccinations.

While science overall is better prepared than it was for Covid, Albrecht said, public health is still under-resourced.

“We’ve never had an adequate public health response because we don’t have an adequate public health system,” Albrecht said. “A preventive public health approach would be better. It requires more resources.”

So far, at least, seasonal flu, which kills dozens of people every day, is more of a threat than bird flu, he said.

And bird flu typically responds to available antiviral drugs, he said, while there’s a stockpile of vaccine that can get the country over the first hump as additional vaccine is made quickly with the mRNA technology used for Covid.