The outbreak of H5N1 avian influenza in dairy cows within the United States, first reported on March 25, has now spread to at the least 33 herds in eight states. Genetic evidence of the virus was recently present in industrial milk. Federal authorities maintain the milk supply is secure, but this latest development raises troubling questions on how widespread the outbreak actually is.
So far there is just one confirmed human case. Rick Bright, an authority on the H5N1 virus and a member of President Joe Biden's coronavirus advisory committee, told me that is the defining moment. “There is a fine line between one and 10 people with H5N1,” he said. “By the time we discover 10, it’s probably too late” to contain it.
So I told him what I had heard from Sid Miller, the Texas agriculture commissioner. He said he strongly suspects the outbreak occurred at the least in February. The commissioner speculated that as much as 40% of herds within the Texas panhandle could have been infected on the time.
Bright was silent after which asked a really sensible query: “Isn’t anyone monitoring this?”
The H5N1 outbreak, already a devastating crisis for cattle farmers and their herds, has the potential to change into an infinite tragedy for the remainder of us. But after spending the last two weeks attempting to get answers from our nation's health officials, I'm shocked at how little they appear to learn about what's actually happening and the way little of what they know is shared in a timely manner becomes.
How bird flu spreads
How exactly does infection spread between herds? The U.S. Department of Agriculture, the Food and Drug Administration and the Centers for Disease Control and Prevention all say they’re working to search out out.
According to many public health officials, the viral load is especially high in infected cow's milk, raising the chance that the disease could also be transmitted through milking machines or through aerosol spray when milking room floors are cleaned with high-pressure cleaners. Another possible route is cow feed, because the U.S. allows farmers to feed leftover poultry bedding material — feathers, excrement, spilled seeds — to dairy and beef cattle as an affordable source of additional protein.
Worryingly, the USDA told me that it had evidence that the virus had also spread from dairy farms back to poultry farms “through an unknown route.” Well, one thing that goes backwards and forwards between cattle ranches and chicken farms is people. They may travel from cattle farms to pig farms, and pigs are the killer animals for human flu pandemics.
The USDA also told me that it doesn’t know the way many farmers have tested their cattle and doesn’t know the way lots of those tests have come back positive. Whatever testing is finished takes place on the state level or in private laboratories. Recently, the agency made reporting of all positive results mandatory, a protracted overdue step that – without the accompanying negative results – continues to be not enough to present us a whole picture. Additionally, the USDA has mandated testing for dairy cattle moving from one state to a different. It says mandatory testing of other flocks wouldn’t be “practical, feasible or necessarily informative” for “several reasons ranging from laboratory capacity to test turnaround times”. At most, the authority will recommend voluntary testing for cattle that show symptoms of the disease – which will not be the case for all infected people. Bright compares this to the Trump administration's approach to COVID-19: If you don't test, it doesn't exist.
The FDA tells me it has not conducted any specific tests to substantiate that pasteurization would make milk from infected cows secure, although the agency considers this “very likely” based on extensive testing for other pathogens. (It will not be yet clear whether the weather of the H5N1 virus that recently appeared in milk have been completely neutralized.) These tests must be accomplished by now. In any case, unpasteurized milk stays legal in lots of states.
Making matters worse, the USDA did not share the genomes of infected animals in a timely manner and did so in an unwieldy format and without geographic information, leaving scientists tearing their hair out in frustration.
Too few tested
All of this makes it so urgent to discover potential human cases. Bright says that given a situation like this and the incontrovertible fact that undocumented farmworkers may not have access to health care, the federal government should use all sophisticated surveillance techniques, including wastewater testing, and publicly release the outcomes. That doesn’t occur. The CDC says it’s monitoring emergency room data for signs of an outbreak. By the time enough individuals are sick enough to be noticed within the emergency room, it's almost definitely too late to stop it.
Local individuals are doing their best. Adeline Hambley, a health official in Ottawa, Michigan, told me a few farm whose herd had tested positive. The farm owner voluntarily provided the cellphone numbers to the employees and the employees received text messages asking them to report any potential symptoms. Lynn Sutfin, an information officer on the Michigan Department of Health and Human Services, told me that the response rate to those texts and other types of outreach could be as high as 90%. That's encouraging, however it's an excessive amount of to expect that a poor farmworker – out of fear of stigma, legal problems and economic loss – will all the time report even mild symptoms and stay home from work as instructed.
It's entirely possible that we'll get lucky with H5N1 and never manage to spread amongst humans. Transmission from animals to humans is common, but pandemics are rare because they require a sequence of unlucky events to occur one after the opposite. But pandemics are a numbers game, and a large-scale animal outbreak like this increases the risks. When dangerous novel pathogens emerge in humans, there is just a small window of opportunity to stop them before they get uncontrolled. Neither our animal husbandry practices nor our public health tools seem as much as the duty.
image credit : www.mercurynews.com