“No one saw this coming.”California dairy farms scramble to protect flocks from bird flu

Early this spring, California dairy farmers noticed a mysterious decline in milk production in Texas, New Mexico, Idaho, Ohio, Kansas, and Michigan. A few weeks later, news broke that several herds in those states and North Carolina had been diagnosed with avian influenza. Bird flu is the same strain of avian influenza that has devastated bird populations around the world. demonstrated the troubling ability to jump on mammals.

To prevent infection of local herds, authorities such as California have imposed restrictions on cattle imports from affected states, and the U.S. Department of Agriculture has advised livestock managers to move cattle as little as possible. We urge them to keep it to a minimum.

Although the U.S. Centers for Disease Control and Prevention believes the current risk to the general public is low, the development has shaken dairy farmers. U.S. dairy cows have never been infected with the H5N1 avian influenza virus.

“Nobody expected this to happen,” said Michael Payne, a researcher and outreach coordinator at the Western Institute for Food Safety at the University of California, Davis.

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Scientists and health organizations around the world have been tracking the spread of the virus for years.

From 2021 onwards, Hundreds of millions of farmed poultry It has infected more than 48 species of mammals, including humans, and countless wild birds. It has also proven particularly deadly among some commensal mammals, including elephant seals and sea lions in South America and caged, fur-fed animals in Europe.

Nevertheless, the outbreak among dairy cows has caused a severe shock.

In addition to the cows being infected, a Texas farm worker who had close contact with infected dairy cows was also infected, but his symptoms were mild. This was the second human case confirmed in the United States.

Although the farmworkers' symptoms are mild, some are concerned that they may continue to be infected.

“The alarming trend of multiple states reporting cattle infections increases the likelihood of continued human exposure,” said Suresh Kuchipudi, professor and chair of the Department of Infectious Diseases and Microbiology at the University of Pittsburgh. he said. “This could amplify the risk of further adaptation of the virus and facilitate human-to-human transmission.”

Public health advocates, wildlife biologists and epidemiologists say there are several reasons why the cattle outbreak surprised farmers and authorities.

First, while there have been sporadic infections of cattle through other influenza strains in the past, no other avian influenza has evolved the ability to transmit between cattle and other ruminants, Kuchipudi said. said.

“It was a surprise,” he said. “It's completely unprecedented.”

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And second, there is no single federal or state agency responsible for tracking this disease, which affects wildlife, agriculture, and public health. Some experts say this is a flawed, silo-like approach to the virus that involves multiple government agencies at home and in other countries.

“This is a fundamental problem in our surveillance systems, especially when it comes to emerging and zoonotic diseases such as avian influenza,” Kuchipudi said. “This is a public health issue, a wildlife issue, and a livestock issue,” so a One Health solution that includes all three elements is extremely important in terms of information gathering and managing communications. Could be helpful.

For example, it's still unclear how cattle became infected with the disease, but if farmers had looked out for sick birds and wildlife and contacted wildlife conservation groups and the Farm Bureau, the spread could have been contained. could have been, experts say.

The California Department of Food and Agriculture is now urging farmers to be on the lookout for sick birds and mammals, humanely remove migratory birds and waterfowl that may come into contact with their flocks, and take steps to prevent them from nesting nearby. I'm looking for it.

It is also possible that the disease was transmitted through infected poultry bedding, a mixture of poultry waste, spilled feed, feathers, and other waste scraped from the floors of industrial chicken and turkey production plants. There are also concerns that this may not be the case. Some farms use it to feed cattle. Payne, a professor at the University of California, Davis, said poultry waste in California is processed at high temperatures that kill the virus, so it's unlikely to be a concern.

The practice is banned in the United Kingdom, the European Union and Canada, where concerns about the spread of bovine spongiform encephalitis, a form of mad cow disease, have deemed it too dangerous.

Despite concerns expressed by some experts, California officials say existing avian influenza surveillance efforts are effective.

State Veterinarian Annette Jones said they are working fluidly with multiple state and federal agencies, including the U.S. Department of Agriculture.

“We have veterinarians and experts across the state who can do the initial investigation, and if we believe there may be a human health issue, we have a California Public Health Department with ties to the county. We will also work closely with the Department of Public Health and the CDC,” she said. “To an outsider, it probably looks like acronym soup, right? But to an experienced insider, we know.”

Mr Jones and other dairy and agriculture sector officials say there is no reason for the public to be alarmed or concerned about cows infected with avian influenza.

They say the reaction in infected cows is mild and gets better quickly. Additionally, milk is pasteurized, so even if infected milk enters your body, the virus will be killed.

But some say the most worrying question is “What happens next?”

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“We want to address what's going on and prevent something worse from happening,” said J. Scott Weese, a professor at the Ontario Veterinary College and director of the Center for Public Health and Zoonoses at the University of Guelph. Ta. “What's worse is that this virus is easily transmitted between humans and can cause serious illness.”

Experts say the disease has already defied all expectations, from its ability to infect different species to its international spread and duration. Crystal Heath, a Bay Area veterinarian and co-founder of the animal rights group Our Honor, said the presence of these animals in mammal-based factory farms should double the scrutiny and concern. Ta.

“Hundreds or thousands of genetically similar animals live together in the same space, standing in each other's waste and breathing,” Heath said. “It's a Shangri-La for opportunistic viruses.”

And Weese said it's still unclear how widespread the virus is and how long it's been infecting cattle.

The fact that observers were noticing a decline in milk production in states where herds are currently known to be infected suggests that the infection may have been present for weeks or even months. Some people are suggesting that. And if the symptoms in cattle or humans are mild enough to not require veterinarian or medical attention, the infection can spread and evolve further, Weese said. This includes finding a mammalian host for human or avian influenza, giving the infection an opportunity to spread. Mix and reassemble.

That's why so many people are now turning to factory pigs and hogs, said Matthew Hayek, an assistant professor at New York University's School of the Environment. Pigs are thought to be effective as recombinant factories for influenza — Mammalian vessels that mix human and avian influenza viruses in a potentially lethal manner.

“This is an issue not only for our food production, but also for our safety as a species,” he said.

This story was originally Los Angeles Times.