As virus spreads, so too does pessimism about halting spread

Fowl flu snapshot: That is the newest installment in a collection of normal updates on the H5N1 flu outbreak in dairy cows that STAT is publishing on Monday mornings. To learn future updates, you too can subscribe to STAT’s Morning Rounds publication.

There are extra human instances of H5N1 chicken flu an infection, and one other state has joined the checklist of these with contaminated dairy cow herds.

Colorado introduced Sunday evening that 5 employees concerned within the culling of chickens at an H5N1-infected poultry operation had examined optimistic for the virus. 4 of the instances have been confirmed by the Facilities for Illness Management and Prevention; the fifth is at present deemed “presumptive” optimistic as a result of the person’s take a look at pattern hasn’t but reached the CDC. All 5 had delicate signs — conjunctivitis and minor respiratory complaints. None required hospitalization.

Extra testing by the CDC is required to completely characterize the viruses chargeable for these infections. However assuming they’re the identical because the one circulating in cows (which has often spilled over into poultry operations), these instances will deliver to 9 the variety of human infections recorded since this outbreak was first detected in late March. The CDC, on the request of the state, helps examine the brand new human instances in Colorado.

And on Friday got here information that one other state had found a chicken flu-infected herd. Oklahoma announced {that a} pattern collected in April that was solely just lately examined was discovered to be optimistic. No rationalization was given for the remarkably sluggish turnaround within the testing of the pattern. Oklahoma referred to as itself the thirteenth state to search out H5N1 in dairy cattle, however in actuality its place on the checklist ought to be decrease, as a number of states solely found optimistic herds in Might and June.

These new human and animal developments help a blunt danger evaluation from the Norwegian Institute of Public Well being, which gave voice to a rising sense of pessimism concerning the prospects for holding the H5N1 outbreak in cows in a latest report.

“There are not any clear indicators that the outbreak is or is about to return underneath management,” the 26-page doc on the general public well being dangers related to the continued unfold states plainly.

“The danger that the state of affairs is not going to quickly be introduced underneath management is nice,” it continues, including that “the chance of … and protracted chains of an infection is taken into account excessive.”

As for the results of continued unfold, the report means that whereas the chance the virus at present poses to individuals isn’t nice, it may rise if transmission in cattle persists.

“There’s a low, however rising chance of viruses creating the flexibility to contaminate successfully to and between individuals,” it says. “The chance will increase with prevalence in animals and with the period of ongoing animal-to-animal an infection.”

The risk assessment, dated June 24, is quickly transformed into English by Google Translate for non-Norwegian readers.

It’s reflective of what seems to be a rising view, definitely overseas however probably within the U.S. as properly, that H5N1 isn’t in any hurry to surrender on its new hosts and nothing farmers or authorities businesses are doing appears to be hastening its departure. (There may be additionally a good diploma of skepticism about how exhausting farmers or the company main the response, the U.S. Division of Agriculture, are working in the direction of that finish.)

Michigan, which has been the exemplar state by way of its efforts to search out and report affected herds and to achieve the belief of cautious farmers, had gone nearly a month with out reporting a brand new contaminated herd. On July 5, it introduced a herd in Gratiot County, which has been battling each poultry and dairy cattle outbreaks since early Might. Texas has gone three weeks with out including to its checklist of affected herds. That modified on July 8.

As of Friday, the USDA had listed 152 herds in 12 states as having examined optimistic for H5N1 because the outbreak was first confirmed in late March. Oklahoma provides one to every of these figures.

Whereas the depend of affected herds has risen steadily in just a few of the reporting states — assume Michigan, Colorado, Idaho — the variety of states with dairy industries that haven’t reported a single outbreak puzzles consultants monitoring this example. (Some are downright dubious.) California, Wisconsin, New York, Pennsylvania, and Washington are on the highest 10 checklist of dairy-producing states by income. Not a type of 5 has reported an affected herd.

Are they luckier? Extra vigilant? Do cows transfer round much less regularly in these states? We don’t but have these solutions. However a information report from Missouri final week could assist clarify a potential distinction between reporting and non-reporting states. (Missouri is without doubt one of the latter.)

Reporter Mary McCue Bell in the Columbia Missourian quoted a veterinarian with the Missouri Division of Agriculture’s animal well being division saying that so far solely 17 dairy cows — in a state that boasts 60,000 — have been examined for H5N1.

There’s a maxim in epidemiology: Search and ye shall discover. It will appear some states should not in search of.

The dearth of a transparent image of how widespread the outbreak is in cattle continues to hamper efforts to evaluate whether or not this outbreak could be stopped and the way finest to do it if that finish is inside attain.

Requested Thursday in the event that they thought the virus could be pushed out of dairy cattle at this level, senior World Well being Group outbreak response leaders hedged their bets. Maria Van Kerkhove, performing director of WHO’s division of epidemic and pandemic preparedness and prevention, stated at this level too little is thought concerning the outbreak to make a prediction by hook or by crook.

“I believe that’s an advanced query,” Van Kerkhove stated throughout a WHO press briefing. “It doesn’t imply that it couldn’t occur. However I believe that earlier than we will get to a solution of when or if that could possibly be potential, we have to perceive the extent [of spread].”

And Mike Ryan, who heads the worldwide well being company’s well being emergencies program, stated the continued presence of the virus in wild birds will proceed to complicate efforts to regulate H5N1’s unfold in home animals. It’s not only a query of driving it out, the objective must be protecting it out of an animal inhabitants — whether or not that’s poultry or dairy cattle. And that takes assets, surveillance, and long-term dedication from the veterinary, wildlife, and public well being sectors, he stated.

“And sadly on the planet the place we search for silver bullets and the remedy that may remedy all the pieces, sadly the remedy for many of our ills as a human civilization is cooperation, coverage, assets and the desire to do the job,” Ryan stated.

Since USDA confirmed the presence of the virus in dairy cattle on March 25 there have been 4 confirmed and three presumptive human infections, all amongst farmworkers. All of the people had delicate signs; some had solely conjunctivitis, whereas just a few have had respiratory signs that resemble what’s seen with an infection with human flu viruses.

The announcement of the fourth case, on the eve of the July 4 vacation, led Adam Kucharski, the co-director of the Centre for Epidemic Preparedness & Response, on the London Faculty of Hygiene and Tropical Medication, to ask on the social platform X: “What’s the plan?”

Kucharski posed a bunch of hypotheticals — What if there are clusters of instances? Circumstances amongst individuals who haven’t had contact with cows? Circumstances exported to different nations? — to convey the purpose {that a} mere 4 years after the beginning of the worst pandemic because the 1918 Spanish Flu, the world doesn’t look like grappling with the truth that H5 virus spreading in cows may result in H5 virus spreading in individuals.

“What, right here in 2024, is the plan for coping with an outbreak of a probably pandemic pathogen like H5N1?” he requested.