Enlarge / Holstein cows at a dairy farm. (credit: Getty | John Carl D'Annibale)

Another dairy farm worker in Michigan has been infected with avian influenza virus, state and federal health officials reported Thursday.

The case marks the third time the outbreak of bird flu in milking cows is known to have spilled over to a human. The dairy farm worker in Michigan, like the others, had close contact with H5N1-infected dairy cows, suggesting another case of cow-to-human transmission.

But the case reported today is notable for being the first one involving respiratory symptoms. In the first two cases, the dairy workers (one in Texas, the other in Michigan) reported only eye infections (conjunctivitis). This third case—also in Michigan but from a different farm—reported upper respiratory symptoms, including cough, congestion, and sore throat, as well as eye discomfort and watery discharge, but not conjunctivitis. The worker was given an antiviral (Tamiflu) and is said to be recovering. No other workers on the farm have shown symptoms, and the worker's household contacts are being monitored.

Enlarge (credit: Digicom Photo/Science Photo Library via Getty)

The US government is nearing an agreement to bankroll a late-stage trial of Moderna’s mRNA pandemic bird flu vaccine, hoping to bolster its pandemic jab stockpile as an H5N1 outbreak spreads through egg farms and among cattle herds.

The federal funding from the government’s Biomedical Advanced Research and Development Authority, known as BARDA, could come as early as next month, according to people close to the discussions.

It is expected to total several tens of millions of dollars and could be accompanied by a commitment to procure doses if the phase-three trials are successful, they said.

Enlarge / Suri alpacas on a farm in Pennsylvania. (credit: Getty | Susan L. Angstadt)

Four backyard alpacas in southern Idaho have tested positive for highly pathogenic avian influenza (HPAI) H5N1, marking the first time bird flu has been detected in members of the fleecy camelid family, according to the US Department of Agriculture.

On Tuesday, the USDA announced that the agency's National Veterinary Services Laboratories confirmed the infection on a farm in Jerome County on May 16. While the infections are a first for the spitting llama relatives, the USDA said they weren't particularly surprising. The alpacas were in close contact with HPAI-infected poultry on the farm, which were "depopulated" this month. Of 18 alpacas on the affected farm, only four were found to be infected. There were no deaths documented, according to a report the USDA submitted to the World Organization for Animal Health.

Genomic sequencing indicates that the H5N1 virus infecting the alpacas (B3.13) matches both the virus currently circulating among US dairy cows and the virus that infected birds on the farm.

Enlarge / Fresh raw milk being poured into a container on a dairy farm on July 29, 2023, in De Lutte, Netherlands. (credit: Getty | Pierre Crom)

Despite the delusions of the raw milk crowd, drinking unpasteurized milk brimming with infectious avian H5N1 influenza virus is a very bad idea, according to freshly squeezed data published Friday in the New England Journal of Medicine.

Researchers at the University of Wisconsin-Madison squirted raw H5N1-containing milk from infected cows into the throats of anesthetized laboratory mice, finding that the virus caused systemic infections after the mice were observed swallowing the dose. The illnesses began quickly, with symptoms of lethargy and ruffled fur starting on day 1. On day 4, the animals were euthanized to prevent extended suffering. Subsequent analysis found that the mice had high levels of H5N1 bird flu virus in their respiratory tracts, as well their hearts, kidneys, spleens, livers, mammary glands, and brains.

"Collectively, our data indicate that HPAI [Highly Pathogenic Avian Influenza] A(H5N1) virus in untreated milk can infect susceptible animals that consume it," the researchers concluded. The researchers also found that raw milk containing H5N1 can remain infectious for weeks when stored at refrigerator temperatures.

Enlarge / Holstein dairy cows in a freestall barn. (credit: Getty | )

A dairy farm worker in Michigan has tested positive for an H5 bird flu virus, marking the second human case of bird flu that has been linked to the unprecedented outbreak of highly pathogenic avian influenza H5N1 virus among dairy cows in the US.

According to the Centers for Disease Control and Prevention, the worker only experienced a mild eye infection and has since recovered, much like the first case in a dairy farm worker in Texas. The Michigan worker was being monitored for symptoms due to exposure—the person worked on a dairy farm with H5N1-infected cattle.

In a press briefing Wednesday afternoon, CDC Principal Deputy Director Nirav Shah said the person was taking part in an active surveillance system, in which the state's health department sent out a text message every day asking about the presence of any symptoms. The worker's infection was identified after the person responded that there were symptoms.

Enlarge / A glass of fresh raw milk in the hand of a farmer. (credit: Getty | Pierre Crom)

To drink raw milk at any time is to flirt with dangerous germs. But, amid an unprecedented outbreak of H5N1 bird flu in US dairy cows, the risks have ratcheted up considerably. Health experts have stepped up warnings against drinking raw milk during the outbreak, the scope of which is still unknown.

Yet, raw milk enthusiasts are undaunted by the heightened risk. The California-based Raw Milk Institute called the warnings "clearly fearmongering." The institute's founder, Mark McAfee, told the Los Angeles Times this weekend that his customers are, in fact, specifically requesting raw milk from H5N1-infected cows. According to McAfee, his customers believe, without evidence, that directly drinking high levels of the avian influenza virus will give them immunity to the deadly pathogen.

Expert Michael Payne told the LA Times that the idea amounts to "playing Russian roulette with your health." Payne, a researcher and dairy outreach coordinator at the Western Institute for Food Safety and Security at UC Davis, added, "Deliberately trying to infect yourself with a known pathogen flies in the face of all medical knowledge and common sense."