State agriculture officials on Thursday banned Fresno-based Raw Farm from distributing its raw dairy products to retailers amid ongoing concerns about possible bird flu infections among its cattle.
However, with the exception of two limited recalls announced in the last few days, products from the farm that are already on store shelves can remain available for sale.
The ban on distribution was issued as a clearer picture emerged regarding whether H5N1, the virus that causes bird flu, had infected cows at Raw Farm. After several days of contradictory test results, in which county public health departments found positive samples in bottled raw milk on store shelves and state agriculture officials did not detect the virus in bulk milk tests, Raw Farm owner Mark McAfee said a new round of tests conducted at the farm Wednesday turned up positive.
The decision to halt distribution of the raw milk added to growing concern among public health experts about the virus.
¡°The fact that H5N1 continues to spread unabated and then surprising us by infecting milk and people in places we don¡¯t expect is bad,¡± said Jennifer Nuzzo, a professor of epidemiology and director of the Pandemic Center at Brown University School of Public Health. ¡°It stokes my concerns that we are giving this virus a runway to launch a pandemic.¡±
On Thursday, California¡¯s agriculture department reached out to McAfee and instructed him to suspend all new sales to retailers. McAfee said he is allowed to sell and distribute cheese that was produced before the state ordered a quarantine on his herds Thursday.
¡°When raw milk disappears from the stores, that will be it,¡± he said.
According to McAfee, neither the agriculture department nor health department has recalled any products other than those involved in two limited recalls made in the last week involving quarter-gallon ¡°cream top¡± whole milk products.
McAfee said until the tests this week by agriculture department officials found the virus, he had not been aware his cows had the disease because ¡°they do not show the classic signs or symptoms. They are mostly all asymptomatic.¡±
Now, he said, ¡°Obviously, we have some asymptomatic shedders at very low levels.¡±
He said two or three of his 1,800 cows had spiked fevers on Oct. 10, but he said they did not test positive for the virus. He said he removed those cows from the herd.
It is unclear how long those cows were separated from others, or if a veterinarian or other professional tested the animals for H5N1.
McAfee said he monitors each cow at his farms with a device that sits in a part of the cow¡¯s stomach and sends real-time information about the animal¡¯s body temperature, milk acidity, etc.
Last week, public health investigators from Santa Clara County tested a retail sample of raw milk they acquired at a store. That sample tested positive for H5N1 bird flu. The state¡¯s public health department soon confirmed that finding and Raw Farm recalled a specific batch that was already off the shelves.
Meanwhile, the state¡¯s agriculture department, which had been routinely testing Raw Farm milk products, kept getting negative results ¡ª leaving infectious disease experts confused.
Then on Wednesday, Santa Clara County Public Health officials announced tests found that a second bottle of milk from Raw Farm was presumptively positive for H5N1. They made the announcement only hours after state agriculture investigators swept Raw Farm¡¯s two herds, creamery, trucks and milk tank for samples.
Questions to the state¡¯s agriculture and public health departments, which were closed for the Thanksgiving holiday, went unanswered Friday.
On Wednesday, health officials from Los Angeles County¡¯s public health department expanded its list of retail stores that may have carried recalled raw milk products.
Untroubled by the positive tests and the possibility of selling raw milk products tainted with the bird flu virus, McAfee told The Times that he is urging consumers to ¡°get to the store. Immediately!¡±
The magnitude of the risk to raw milk consumers is unclear. So far, 55 Americans have contracted H5N1 bird flu this year; these were predominantly dairy and poultry workers who were likely infected through their close proximity to animals and not by consuming contaminated products.
In two of those cases the source has not been identified, including a child in Alameda County who tested positive earlier this month.
In addition, a teenager in British Columbia was infected more than two weeks ago and has been in critical care since. Investigators think the source ¡ª based on its genetic sequencing ¡ª is related to wild birds, not cows.
¡°My biggest concern about finding the virus in raw milk is the potential for harm to the people who consume it,¡± said Nuzzo, the Brown University espidemiologist. ¡°We haven¡¯t yet seen people get H5N1 from drinking raw milk, but it¡¯s reasonable to worry they might.¡±
Richard Webby, director of the World Health Organization¡¯s Collaborating Center for Studies on the Ecology of Influenza in Animals and Birds, and a researcher in the department of infectious diseases at St. Jude Children¡¯s Research Hospital in Memphis, Tenn., agreed.
¡°Folks have fed infected milk to calves and they have not become infected. The same can¡¯t be said for mice, ferrets and cats. Are humans more cow like or mice/ferret/cat? I guess that¡¯s the question,¡± he said. ¡°We don¡¯t have the answer. But still, for sure not a chance I would take.¡±
McAfee said he hopes enough cows on his farms will become infected with bird flu to reach levels required to develop herd immunity. If that happens and the state clears retailers to once again restock store shelves with his products, ¡°all of our raw milk will have antibodies to influenza HPAI H5N1. That¡¯s awesome!¡±
The findings come at a time when President-elect Donald Trump¡¯s nomination for Health and Human Services, Robert F. Kennedy Jr., has voiced his support for raw milk and has said he wants to increase people¡¯s access to unpasteurized milk.
According to the U.S. Department of Agriculture, since August cows in 474 dairy herds in California have tested positive for bird flu. That¡¯s roughly half of the more than 900 dairy herds in the state.
Nationwide, bird flu cases in 688 dairy herds have been identified across 15 states.