Late March, The United States Department of Agriculture (USDA) announced that a case of avian influenza has been detected in a dairy cow.Originally discovered on dairy farms in Texas, Kansas, and New Mexico, 36 individuals have now been identified. Outbreaks in dairy herds in nine states.
The H5N1 virus is prevalent among wild birds and is currently circulating among dairy cows in the United States. USDA has confirmed transmission between cattle within the same herd, from cattle to birds, and between different cattle. herd of dairy cows.
However, the reported outbreaks are likely to significantly underestimate the true spread of the virus, says James Wood, head of the University of Cambridge’s School of Veterinary Medicine. “There’s probably going to be a significant amount of underreporting and underdiagnosis,” he says.
Testing of retail milk samples by the Food and Drug Administration (FDA) could give some indication of how widespread the virus is. The agency found virus fragments in one in five commercial milk samples, but the virus had been inactivated by pasteurization and was not infectious.
So far, only one human infection has been confirmed in this outbreak, an infected person in Texas who had close contact with dairy cows.The only reported symptom It was conjunctivitis, and the person was told to isolate and take antiviral medication for the flu.But anecdotal reports of illness on dairy farms suggest infection among humans may be more widespread than official. data suggests. Although human infections tend to be rare, the virus is dangerous, accounting for just over half of the human infections recorded by the World Health Organization over the past 20 years. It was deadly.
James Lawler, a professor of infectious diseases at the University of Nebraska Medical Center, said dairy workers are most at risk from the current outbreak, but it’s very difficult to gauge how infected they are. More than half of U.S. dairy industry workers immigrationand many Of these Not documented.
These undocumented workers are unlikely to want to put themselves at risk by coming for a test, Lawler said. “There is an inherent disincentive for many workers to not raise their hands because of their status as illegal immigrants.” As a result, it is difficult for scientists to track the potential spread of the virus through the human body. Lawler said it has become difficult.
Another issue is encouraging dairy farm owners to report when their animals become sick. The USDA Animal and Plant Health Inspection Service provides payments to poultry farmers who must kill livestock for reasons such as, among other things: avian influenza infection. Because dairy farmers are not compensated for reporting infections, producers tend to remain silent, increasing the risk that outbreaks can get out of control and spread to other cattle and farm workers.
This poses a major problem in tracking the spread of the disease. “From a producer’s perspective, what are the benefits of sharing and even testing to understand if there is a virus circulating in the herd?” Lawler said.
