Category: Flu Virus

A deadly strain of avian influenza has breached the fragile ecosystem of the world's most remote continent. Scientists say it's only a matter of time before it reaches Australia.

Antarctica is home to some of the world's most unique animals.

Now, scores of them are dying in "mass mortality events", the likes of which the continent has never seen.

The bodies of Adliepenguins and skuas are lined up on the snow and ice as adeadly, mutating pathogen continues its unrelenting spread, infecting new species of birds and mammals across the globe.

It was quite devastating, every couple of metres youre finding another dead bird," Australian researcher Dr Meagan Dewar told 7.30.

A multinational crew of scientists led by Dr Dewar made the grim Antarctic finding on their most recent disease surveillance expedition in March.

Among the casualties were dozens of skuas the big brown seagull-like birds had suffered a sudden death.

"It's devastating that we may have lost a population, just as we've discovered it," Dr Dewar told 7.30.

With a theory in mind, they ran experiments to be sure.

Taking tissue samples from the skua carcasses aboard their yacht, they performed tests, similar to the sequencing of COVID-19.

Their findings, while not unexpected, did come with a heavy reality.

A mutated strain of the virus we know as "bird flu" had penetrated the world's most remote continent.

"Sadly, it's something we predicted; it was something that was going to happen."

While the extent of the pathogen's spread in Antarctica remains unknown, tests are being conducted to find out what killed thousands of Adliepenguins on nearby Heroina Island.

Dr Dewar said there were clues to indicate sudden death as their bodies appeared healthy and many had food in their stomachs.

"It indicates most likely [the cause of death was] an infectious disease of some sort," she told 7.30.

Samples from the penguins are still being analysed.

Heroina is classified as the third-largest Adliepenguin colony in the world.

There are now concerns for all bird and mammal species across the continent.

"Now that it's moved onto the peninsula, there's a greater risk it'll spread to other parts of Antarctica," Dr Dewar said.

Skuas are known to frequently move between animal populations across Antarctica,and could potentially spread the virus to penguin colonies next season.

"We do know there are species that mix with similar species from different populations during winter, so there's a chance of [further] spreading the virus and taking it back to their colonies," Dr Dewar said.

The working theory for the Antarctic spread is relatively simple, and commonly attributed to most other bird flu outbreaks: wild birds.

In this case, it's suspected infected skuas carried the virus from the sub-Antarctic Falkland Islands and South Georgia Island, where there were several known hotspots including infections in mammals.

Those sub-Antarctic cases were introduced by birds who carried the deadly strain from South America, which has seen bird populations decimated in recent years.

Developments have been closely monitored and logged by the Scientific Committee on Antarctic Research (SCAR), and show a clearly defined route.

Virus Ecologist Dr Michelle Wille has been tracking bird flu for years.

"If we look at what's happening around the world this virus has arrived and left a trail of destruction, we're talking species-level consequences," she told 7.30.

"The worst-case scenario is arriving at penguin colonies that are silent, arriving at places where there should be abundant wildlife and having nothing.

"It's very hard to predict what's going to happen in the next season, or even this winter."

Bird flu isn't anything new.

It became a well-known virus in the late 1990s, when an outbreak in a Hong Kong poultry market resulted in the deaths of several people.

The disease then appeared in other birds and poultry throughout Asia, before breaching Europe, spreading into Africa and reaching the Americas.

There have been more strains between then and now but since 2020, a mutated strain of bird flu has had unprecedented impacts on poultry and wild birds on a global scale.

It's officially labelled HPAI (Highly Pathogenic Avian Influenza) H5N1 clade 2.3.4.4b.

It is often referred to as "H5N1".

In the context of infectious diseases, scientists agree this is the worst ecological disaster yet.

"I don't think any of us could have imagined it's been as bad as it is now, but since 2020-21, things have gotten to a whole new level," Dr Wille told 7.30.

"The scale of the mortalities is also something we've never seen before and there's no evidence that it's stopping any time soon."

Arguably, the most confronting supporting evidence comes from South America.

In Peru, at least 40 per cent of the native pelican population has been wiped out.

More than 10 per cent of the penguin species have been affected as well.

And this strain is not just killing birds more than 10 per cent of sea lions have died across the continent.

The list goes on.

Globally, more than 500 bird species have been affected, and more than 60 mammalians.

In poultry, some of the worst outbreaks have been recorded in the United States. The Centre for Disease Control estimates total losses exceeding 90 million chickens and turkeys across 48 states.

And the most recent unexpected developments with bird flu have come in the US.

Authorities there are dealing with the fallout from a peculiar "spillover" event which is when animals pass the virus to other species.

Somehow, a herd of dairy cattle became infected, spreading it to other bovines, and to at least one person a farmer who reported having mild flu symptoms and conjunctivitis.

The transmission to multiple species and humans has raised questions.

While this strain has jumped species and finds new hosts with ease, scientists say there is little concern for humans at present.

A team of Australian scientists at the CSIRO's Centre for Disease Preparedness (ACDP) are an authority on the matter and back that statement.

Dr Frank Wong, who is a global authority on avian flu, described humans as "dead-end hosts", which means an infected person cannot pass it on to others.

"In the few cases where people have got infected, they've mainly been people at the front lines dealing with the outbreak or infection," Dr Wong told 7.30.

"The virus still hasn't been able to easily transmit from a mammalian host from person-to-person or mammal-to-mammal."

Dr Wong and others know this because of their research, which takes place inan airtight high-biosecurity laboratory where they're growing the latest H5N1 strain to study it more closely.

The virus is injected into eggs and replicates itself before being harvested.

This is also how some vaccines are developed.

So if the day ever comes when we need one for bird flu, they already know how to develop it.

No one is certain, but the highest risk period for Australia is theorised to be from September the start of Spring.

That's when migratory birds are expected to make their return from Europe.

The first place of incursion depends on which birds (species and populations) are involved.

Shorebirds stop along the top end of Australia first where places like Broome are important sites.

But some fly directly to the country's southern parts, bypassing the top end.

If it arrives with seabirds, like muttonbirds, it would first arrive at their colonies, and this could be across many places.

Some sectors are watching more closely than others.

Australia's poultry industry, which has fallen victim to a number of past deadly outbreaks, including previous strains of bird flu, has increased biosecurity to its strictest level yet.

A bleak picture has been painted in Australia's Avian Influenza Plan, written by a National Biosecurity Committee.

It suggests our domestic economy could suffer from a widespread outbreak and disruptions within the poultry sector.

Export markets for chicken products would "likely close immediately".

It predicted other industries, including tourism, would be affected.

There are grave concerns for wildlife too, with a widespread outbreak potentially reversing "decades of conservation efforts".

There are currently 163 bird species considered either critically endangered, endangered, or vulnerable and those could be pushed closer to extinction.

"Sometimes that's the last nail in the coffin for some species," Dr Wille said.

"They never recover from something like that, it can be catastrophic.

"The most important thing we can do is monitor ... but I don't think there's any way to stop it once it's in Australian wild birds."

Admitting an outbreak is unavoidable doesn't mean the outlook is hopeless.

For several years, state, territory and federal governments have been preparing and considering an incursion to be inevitable.

You can't stop wild birds at the border, so enhanced surveillance is the key to spotting and controlling any outbreaks.

"Our teams here keep a close eye on genetic evolution of the virus and we know what new strains are emerging as the virus spreads in different parts of the world particularly in our region," Dr Wong told 7.30.

"With influenza, we never say never, but we are confident that we're well prepared for any possible incursion."

In a country as vast as Australia, the public plays an important role too.

We're being asked to immediately report any unusual bird deaths to the Emergency Animal Disease Hotline on 1800 675 888.

Health authorities have also warned against handling sick or dead birds.

Those now in charge, watch, wait and hope.

Reporter: Tom Hartley

Photos and videos: DrMeagan Dewar, Dr Michelle Wille, Ben Wallis

Digital production: Jenny Ky

Editor: Paul Johnson

Watch 7.30, Mondays to Thursdays 7:30pm on ABC iview and ABC TV

Do you know more about this story? Get in touch with 7.30 here.

See original here:

A strain of bird flu has caused 'mass mortality events' on every continent but Australia. Scientists say an outbreak is ... - ABC News

Of all the creatures stricken with this new and terrible H5N1 fluthe foxes, the bears, the eagles, ducks, chickens, and many other birdsdairy cattle are some of the most intimate with us. In the United States, more than 9 million milk cows live on farms, where people muck their manure, help birth their calves, tend their sick, and milk them daily. That kind of proximity is exactly what gives a virus countless opportunities to encounter humansand then evolve from an animals-only virus into one that troubles people too.

But as unnerving as H5N1s current spread in cows might be, I would be a whole lot more concerned if this was an event in pigs, Richard Webby, the director of the World Health Organization Collaborating Centre for Studies on the Ecology of Influenza in Animals and Birds, told me. Like cows, pigs share plenty of spaces with us. They also have a nasty track record with flu: Swine airways are evolutionary playgrounds where bird-loving flu viruses can convertand have convertedinto ones that prefer to infect us. A flu virus that jumped from swine to humans, for instance, catalyzed the 2009 H1N1 pandemic. If theres a list of riskiest animals for an avian flu to infiltrate, pigs are clearly at the top, Webby said.

To successfully spread in a new species, a flu virus must infiltrate that creatures cells, reproduce inside of them, and then make it to the next host. This H5N1 has managed that feat in several animals, but so far, were actually still dealing with a very avian virus, Michelle Wille, a virologist at the University of Melbourne, told me. For the virus to spread widely in humans, scientists think that it would need to pick up several new traits; so far, theyve detected only one such modification, which has boosted the viruss ability to replicate inside mammalian cells.

In particular, the virus does not seem to have acquired what Webby considers the most crucial modification, one that would help it more efficiently enter human-airway cells in the first place. To do that, H5N1 would need to adjust its ability to latch on to particular sugars on cell surfaces, which effectively serve as locks to the cells interior. For decades, though, the virus has preferred the version of those sugars thats most commonly found in the gastrointestinal tract of birds, and still seems to. Experts would really start to worry, Webby said, if it started glomming very tightly instead onto the ones most commonly found in human airways.

Read: Bird flu has never done this before

That said, the difference between those sugars is architecturally quite small. And although scientists might colloquially call some bird receptors and others human receptors, mammals can produce bird receptors, and vice versa. (Humans, for instance, have bird receptors in their eyes, which likely explains why the farm worker who appears to have caught H5N1 from a dairy cow developed only conjunctivitis.) The right animal host could encourage the virus to switch its preference from birds to humansand pigs fit that bill. They just so happen to harbor both bird receptors and human receptors in their respiratory tract, giving the flu viruses that infect them plenty of opportunity to transform.

Just by hanging out in pigs for a while, H5N1 could enhance its ability to enter our cells. Or, perhaps even more concerning, it could encounter a flu that had already evolved to infect humans, and swaps bits of its genome with that virus. Pigs catch our viruses all the time. And should one of those pathogens hybridize with this H5N1, becoming human-adapted enough to spread among people but still avian-adapted enough to elude our immune system, a large-scale outbreak could begin. In the late 1970s, after an H1N1 avian-flu virus hopped from wild waterfowl into Europes pig population, it took just a few years to start infecting people in Europe and Asia. Eventually, that same virus helped birth 2009s pandemic swine flu.

Right now flu surveillance among swine needs to be dialed up, experts told me; protections for farm workers who handle the animals should ramp up too. Seema Lakdawala, a virologist at Emory University, told me that shed also like to see cows milk on farms better contained and more quickly heat-treated, so that other animals in the vicinity wont be exposed to the liquid in its raw form. (Several farm cats, for instance, appear to have caught H5N1 by drinking raw milk on farms.)

At this point, any worry about the virus evolving dramatically in pigs is still theoretical. H5N1 hasnt yet been detected in farm pigs, and experimental infections have found that the virus, although capable of infecting and replicating in swine, doesnt seem to transmit easily among them. Even if that were to change, pigs may not end up being the ideal venue for the many other genetic gymnastics that would help this virus adapt to us.

That said, we dont fully understand all of the mutations or genetic requirements needed to convert an avian virus, Louise Moncla, a virologist at the University of Pennsylvania, told me. Viruses sometimes surprise us: 2009s H1N1 flu, for instance, caused a pandemic without making the genetic change that seems to have helped this new H5N1 along. Which means its not a complete comfort that H5N1 isnt spreading in pigs yetespecially when so many cows are getting sick now.

Read: Americas infectious-disease barometer is off

Scientists know relatively little about flu in cows. Although cattle have been known to catch certain kinds of flu before, the current outbreak is the first time a type-A influenza, the group that H5N1 belongs to, has been detected in their kind. Researchers are only now starting to understand the animals susceptibility to these pathogens, and a recent preprint study, which Webby contributed to, revealed human-esque flu receptors in several parts of the cow body, some of which have bird receptors tooa finding that suggests that the risk posed by continued spread in cows is higher than once thought. Webby, for one, isnt panicking yet, and he told me that the results mainly help explain why cow udders, now confirmed to be full of bird receptors, have turned out to be such great homes for H5N1. And because cows are likely spreading the virus to one another via milking equipmentbasically a free ride for the pathogenthere may be little pressure for the virus to change its MO.

The bigger risk is simpler. The things that make me the most nervous are the species that we regularly interact with all the time, Moncla told me. The more cows catch the virus, the more exposure there will be for us, giving the virus more chances to explore and potentially adapt to our respiratory tract. Commercial milking is a messy affair: The processing machinery sprays and mists the liquid all about. Lakdawala imagines that milking an infected cow without protective equipment could be like me squirting 10,000 or 100,000 viral particles into someones nose. Just one of those particles needs to carry the right set of genetic changes for this flu to become a human one.

Read the rest here:

Pigs Would Be a Dangerous Bird-Flu Host - The Atlantic

Researchers worry that insufficient collection and reporting of data are hampering efforts to assess the scale of the bird-flu outbreak in US cattle and could hold back efforts to bring the virus under control.

We are not doing enough, says Isabella Eckerle, head of the Geneva Centre for Emerging Viral Diseases in Switzerland. For now, the strain of the influenza virus is a long way from being able to transmit easily to and between humans. But the moment it does, it will be an emergency.

For now, the viral strain infecting cows, called H5N1, still prefers to bind to the receptor it uses to infect birds. This receptor is not common in the upper airways of people, says Thomas Peacock, a virologist at Imperial College London. But the virus has acquired some changes that make it better at making copies of its genome in mammals, which is the first step of the pandemic stairs, says Peacock. Adapting to receptors prevalent in humans is several steps further up.

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Scientists are eager to deploy a host of tools to monitor the pathogens evolution. But for these tools to be useful, Eckerle says, you need to have the data about where the infections are happening right now and those data have not been forthcoming.

Actually changing government policy based on guesses rather than information that we could get, but are not getting, is the real problem, says Angela Rasmussen, a virologist at the University of Saskatchewan in Saskatoon, Canada.

Gaps in the data have been apparent since US officials first announced the outbreak in March. An analysis of viral genomes found that H5N1 probably jumped from an infected wild bird to a cow, perhaps as early as November. The virus has been circulating in cattle ever since. The delay in identifying the outbreak suggests that surveillance programmes are not robust, says Jonathan Pekar, an evolutionary biologist at the University of California, San Diego. The infrastructure we have in place is insufficient to prevent future pandemics, he says.

Shilo Weir, a public-affairs specialist at the US Department of Agriculture (USDA), disagrees with that assessment. This event highlights the success of our animal health network, Weir says. It shows that our surveillance program is incredibly effective at early identification of emerging disease trends.

Researchers say that surveillance has continued to falter. The USDA did not release the first viral sequences until weeks after the outbreak was announced. For many of these sequences, the agency has still not released crucial details about when, where and from which species each was collected information that could offer insight into how the virus is moving between herds, as well as how it is evolving, say researchers. Theres not a huge amount of information coming through, or its coming through very slowly, says Peacock. From a pandemic-potential perspective, to try and understand how bad this is and whats going on, its frustrating.

Weir says that to expedite public access, sequence data are initially shared with general USA and 2024 tags, but polished sequences with more detailed information will be uploaded on the the widely used repository GISAID.

Researchers also say that information about what percentage of all sampled animals the sequences represent hasnt been made available. We dont know the full extent of testing, says Rasmussen. That means that researchers cant assess whether the outbreak is growing, has peaked or is experiencing a downturn, says Peacock.

Weir says that national laboratories have conducted more than 7,500 tests since the start of the outbreak. But that number does not reflect exactly how many animals have been tested because some animals might have been sampled multiple times, or swabs from multiple animals could have been pooled into one test, says Weir.

On 24 April, the USDA mandated testing of lactating dairy cows prior to their movement between states, and reporting of positive influenza A test results in livestock. The USDA expects this federal order to improve the understanding of the viruss distribution and reduce the risk of its further spread, says Weir.

Researchers also say more sampling is needed. Almost 50 herds of dairy cattle across 9 US states have had confirmed cases of H5N1, and one infected person has been linked to the outbreak. But the actual numbers are probably much higher, scientists say. Theres almost certainly been a lot more human cases than just the one, says Peacock.

Cattle and people working on farms should be tested not just for the presence of viral RNA which indicates an active infection but also for antibodies against H5N1, which circulate in the body for longer after an infection. This is something that should be done immediately, says Eckerle. Antibody studies could help scientists to determine how many people and cattle have been exposed to the virus and had infections that went unnoticed, possibly because they did not show symptoms or were not tested.

Weir says that the USDA plans to adapt a commercially available antibody test for birds for use in cattle serum and milk.

The sampling of faeces and organs from infected animals would help to identify where in the body the virus is replicating, how it is being excreted and how it is spreading between animals. If the virus is spreading through contact with contaminated milk, that would be relatively straightforward to control, says Eckerle. But transmission through respiratory secretions would be more difficult to control and would make farm work more risky.

Weir says the USDA is continuing to collect epidemiological data, and to study disease pathology and transmission to better understand the virus in cattle.

Some of the data that researchers are calling for could already have been collected but not publicly shared, says Meghan Davis, an environmental and veterinary epidemiologist at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland. This lack of transparency undermines the speed and other capacities for the response, she says.

One barrier to testing has been the lack of incentives for farmers to step forward if they suspect the virus has infected their animals, say researchers.

On 10 May, the USDA announced a plan to compensate farmers affected by H5N1 outbreaks, and those who cooperate in studies, which could see testing ramp up. Davis says these measures should have been introduced weeks ago, especially in an industry in which there are some 25,000 farms making individual decisions. Farm workers should also receive sufficient protection, so that if they fall ill they are comfortable disclosing it, says Pekar.

Information about how and where the virus has spread is important for informing the response. If the outbreak is not widespread and is moving slowly, public-health officials could decide to cull affected herds and eradicate the virus in cattle, says Eckerle. But if it is too widespread or fast-moving, they might have to resign themselves to a new reality in which cattle are a reservoir of H5N1, and focus on restricting its jump to people. I would not say its too late to decide between these two pathways, says Eckerle but we need data.

This article is reproduced with permission and was first published on May 17, 2024.

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Slow Response to Bird Flu in Cows Worries Scientists - Scientific American

Researchers worry that insufficient collection and reporting of data are hampering efforts to assess the scale of the bird-flu outbreak in US cattle and could hold back efforts to bring the virus under control.

We are not doing enough, says Isabella Eckerle, head of the Geneva Centre for Emerging Viral Diseases in Switzerland. For now, the strain of the influenza virus is a long way from being able to transmit easily to and between humans. But the moment it does, it will be an emergency.

For now, the viral strain infecting cows, called H5N1, still prefers to bind to the receptor it uses to infect birds. This receptor is not common in the upper airways of people, says Thomas Peacock, a virologist at Imperial College London. But the virus has acquired some changes that make it better at making copies of its genome in mammals, which is the first step of the pandemic stairs, says Peacock. Adapting to receptors prevalent in humans is several steps further up.

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Scientists are eager to deploy a host of tools to monitor the pathogens evolution. But for these tools to be useful, Eckerle says, you need to have the data about where the infections are happening right now and those data have not been forthcoming.

Actually changing government policy based on guesses rather than information that we could get, but are not getting, is the real problem, says Angela Rasmussen, a virologist at the University of Saskatchewan in Saskatoon, Canada.

Gaps in the data have been apparent since US officials first announced the outbreak in March. An analysis of viral genomes found that H5N1 probably jumped from an infected wild bird to a cow, perhaps as early as November. The virus has been circulating in cattle ever since. The delay in identifying the outbreak suggests that surveillance programmes are not robust, says Jonathan Pekar, an evolutionary biologist at the University of California, San Diego. The infrastructure we have in place is insufficient to prevent future pandemics, he says.

Shilo Weir, a public-affairs specialist at the US Department of Agriculture (USDA), disagrees with that assessment. This event highlights the success of our animal health network, Weir says. It shows that our surveillance program is incredibly effective at early identification of emerging disease trends.

Researchers say that surveillance has continued to falter. The USDA did not release the first viral sequences until weeks after the outbreak was announced. For many of these sequences, the agency has still not released crucial details about when, where and from which species each was collected information that could offer insight into how the virus is moving between herds, as well as how it is evolving, say researchers. Theres not a huge amount of information coming through, or its coming through very slowly, says Peacock. From a pandemic-potential perspective, to try and understand how bad this is and whats going on, its frustrating.

Weir says that to expedite public access, sequence data are initially shared with general USA and 2024 tags, but polished sequences with more detailed information will be uploaded on the the widely used repository GISAID.

Researchers also say that information about what percentage of all sampled animals the sequences represent hasnt been made available. We dont know the full extent of testing, says Rasmussen. That means that researchers cant assess whether the outbreak is growing, has peaked or is experiencing a downturn, says Peacock.

Weir says that national laboratories have conducted more than 7,500 tests since the start of the outbreak. But that number does not reflect exactly how many animals have been tested because some animals might have been sampled multiple times, or swabs from multiple animals could have been pooled into one test, says Weir.

On 24 April, the USDA mandated testing of lactating dairy cows prior to their movement between states, and reporting of positive influenza A test results in livestock. The USDA expects this federal order to improve the understanding of the viruss distribution and reduce the risk of its further spread, says Weir.

Researchers also say more sampling is needed. Almost 50 herds of dairy cattle across 9 US states have had confirmed cases of H5N1, and one infected person has been linked to the outbreak. But the actual numbers are probably much higher, scientists say. Theres almost certainly been a lot more human cases than just the one, says Peacock.

Cattle and people working on farms should be tested not just for the presence of viral RNA which indicates an active infection but also for antibodies against H5N1, which circulate in the body for longer after an infection. This is something that should be done immediately, says Eckerle. Antibody studies could help scientists to determine how many people and cattle have been exposed to the virus and had infections that went unnoticed, possibly because they did not show symptoms or were not tested.

Weir says that the USDA plans to adapt a commercially available antibody test for birds for use in cattle serum and milk.

The sampling of faeces and organs from infected animals would help to identify where in the body the virus is replicating, how it is being excreted and how it is spreading between animals. If the virus is spreading through contact with contaminated milk, that would be relatively straightforward to control, says Eckerle. But transmission through respiratory secretions would be more difficult to control and would make farm work more risky.

Weir says the USDA is continuing to collect epidemiological data, and to study disease pathology and transmission to better understand the virus in cattle.

Some of the data that researchers are calling for could already have been collected but not publicly shared, says Meghan Davis, an environmental and veterinary epidemiologist at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland. This lack of transparency undermines the speed and other capacities for the response, she says.

One barrier to testing has been the lack of incentives for farmers to step forward if they suspect the virus has infected their animals, say researchers.

On 10 May, the USDA announced a plan to compensate farmers affected by H5N1 outbreaks, and those who cooperate in studies, which could see testing ramp up. Davis says these measures should have been introduced weeks ago, especially in an industry in which there are some 25,000 farms making individual decisions. Farm workers should also receive sufficient protection, so that if they fall ill they are comfortable disclosing it, says Pekar.

Information about how and where the virus has spread is important for informing the response. If the outbreak is not widespread and is moving slowly, public-health officials could decide to cull affected herds and eradicate the virus in cattle, says Eckerle. But if it is too widespread or fast-moving, they might have to resign themselves to a new reality in which cattle are a reservoir of H5N1, and focus on restricting its jump to people. I would not say its too late to decide between these two pathways, says Eckerle but we need data.

This article is reproduced with permission and was first published on May 17, 2024.

View original post here:

Slow Response to Bird Flu in Cows Worries Scientists - Scientific American

In an update today on food safety testing in light of H5N1 avian flu detections in some dairy cattle, the US Department of Agriculture (USDA) said that inoculation of ground beef patties with a virus surrogate and cooking them to medium or well inactivated the virus.

In other developments, federal officials during the same briefing announced more than $22.2 million in funding for efforts to control and respond to animal disease outbreaks, including $6 million for the National Animal Health Laboratory Network, which has played a key role in testing samples from potentially infected herds.

Eric Deeble, DVM, the USDA's acting senior adviser for highly pathogenic avian influenza, said that, as part of the department's food safety testing, it wanted to determine what ground beef cooking temperatures could kill H5N1.

Though the virus hasn't been detected in beef cattle, some dairy cattle are used in the production of ground beef. Earlier this month, PCR testing by USDA scientists on retail ground beef samples found no traces of H5N1.

Researchers inoculated the ground beef patties with high levels of an H5N1 surrogate virus, then cooked them to different internal temperatures. Deeble said no virus was found when the beef was cooked to 145F internal temperature (medium) or 160F (well done).

When the virus-laden beef patties were cooked to 120F degrees (rare), however, the tests found evidence of the virus, but at much reduced levels, he said.

Deeble said there are no recommended changes in safe cooking practices and that the longstanding USDA Food Safety and Inspection Service (FSIS) advice is to cook beef patties to an internal temperature of 160F.

In other food safety tests, USDA scientists are testing whole-muscle cuts for any evidence of H5N1, and he said results are expected next week.

Regarding the funding boost for NAHLN labs, there are no concerns about testing capacity, but the infusion will build on existing capacity and add more resources, Deeble said. Some labs need updated equipment, and some of the funding will target research projects within the labs that are aimed at expanding testing methods.

Of the more than $22.2 million announced today to boost animal disease efforts, $16.2 million will target 74 projects to advance animal disease preparedness, such as helping states develop plans and practice quickly controlling animal disease outbreaks.

In addition, $1 million is earmarked for emergency preparedness, and $5 million will go directly to labs for capacity building.

USDA officials today said they wouldn't speculate on the current trajectory of the outbreaks or if activity has peaked.

Deeble said, however, that the lack of recent spread beyond the nine currently affected states may be partly due to the federal rule that requires testing for dairy cows before movement between states.

Meanwhile, Nirav Shah, JD, MD, principal deputy director for the Centers for Disease Control and Prevention (CDC), told reporters that although current findings from the CDC's new influenza A wastewater dashboard are reassuring, the investigation is ongoing. "There's a lot more to be done."

The dashboard, unveiled 2 days ago on the CDC's H5N1 surveillance page, found that, over the past 2 weeks, there were only 3 sites in the high category among 230 that met data reporting criteria. The sites are in Kansas, Florida, and Illinois.

Regarding epidemiologic and scientific investigations, federal officials last week announcedas part of new support for farms and the outbreak responsea $75 financial incentive for farm workers at affected dairy farms to be tested. Shah said so far the CDC hasn't identified any workers who are willing to participate.

He added that the CDC is eager to conduct testing to answer key questions, such as which farm jobs pose the highest risk to workers. There are no plans to add a testing requirement, Shah said. "We would like to do this in voluntary cooperation with farms and farm workers."

Federal officials said they were aware of anecdotal reports that some proponents of drinking raw milk are claiming that drinking H5N1-contaminated milk will boost immunity against the virus. Deeble said the USDA is not aware of any raw milk sold from any of the known outbreak farms. He added that the only way to protect against H5N1 infection from milk is to avoid drinking raw milk.

Even before the H5N1 outbreak in dairy cows was first detected in late March, federal health agencies have had a longstanding recommendation against drinking raw milk because of potential contamination with pathogens.

See more here:

USDA experiments suggest H5N1 not viable in properly cooked ground beef - University of Minnesota Twin Cities

In an update today on food safety testing in light of H5N1 avian flu detections in some dairy cattle, the US Department of Agriculture (USDA) said that inoculation of ground beef patties with a virus surrogate and cooking them to medium or well inactivated the virus.

In other developments, federal officials during the same briefing announced more than $22.2 million in funding for efforts to control and respond to animal disease outbreaks, including $6 million for the National Animal Health Laboratory Network, which has played a key role in testing samples from potentially infected herds.

Eric Deeble, DVM, the USDA's acting senior adviser for highly pathogenic avian influenza, said that, as part of the department's food safety testing, it wanted to determine what ground beef cooking temperatures could kill H5N1.

Though the virus hasn't been detected in beef cattle, some dairy cattle are used in the production of ground beef. Earlier this month, PCR testing by USDA scientists on retail ground beef samples found no traces of H5N1.

Researchers inoculated the ground beef patties with high levels of an H5N1 surrogate virus, then cooked them to different internal temperatures. Deeble said no virus was found when the beef was cooked to 145F internal temperature (medium) or 160F (well done).

When the virus-laden beef patties were cooked to 120F degrees (rare), however, the tests found evidence of the virus, but at much reduced levels, he said.

Deeble said there are no recommended changes in safe cooking practices and that the longstanding USDA Food Safety and Inspection Service (FSIS) advice is to cook beef patties to an internal temperature of 160F.

In other food safety tests, USDA scientists are testing whole-muscle cuts for any evidence of H5N1, and he said results are expected next week.

Regarding the funding boost for NAHLN labs, there are no concerns about testing capacity, but the infusion will build on existing capacity and add more resources, Deeble said. Some labs need updated equipment, and some of the funding will target research projects within the labs that are aimed at expanding testing methods.

Of the more than $22.2 million announced today to boost animal disease efforts, $16.2 million will target 74 projects to advance animal disease preparedness, such as helping states develop plans and practice quickly controlling animal disease outbreaks.

In addition, $1 million is earmarked for emergency preparedness, and $5 million will go directly to labs for capacity building.

USDA officials today said they wouldn't speculate on the current trajectory of the outbreaks or if activity has peaked.

Deeble said, however, that the lack of recent spread beyond the nine currently affected states may be partly due to the federal rule that requires testing for dairy cows before movement between states.

Meanwhile, Nirav Shah, JD, MD, principal deputy director for the Centers for Disease Control and Prevention (CDC), told reporters that although current findings from the CDC's new influenza A wastewater dashboard are reassuring, the investigation is ongoing. "There's a lot more to be done."

The dashboard, unveiled 2 days ago on the CDC's H5N1 surveillance page, found that, over the past 2 weeks, there were only 3 sites in the high category among 230 that met data reporting criteria. The sites are in Kansas, Florida, and Illinois.

Regarding epidemiologic and scientific investigations, federal officials last week announcedas part of new support for farms and the outbreak responsea $75 financial incentive for farm workers at affected dairy farms to be tested. Shah said so far the CDC hasn't identified any workers who are willing to participate.

He added that the CDC is eager to conduct testing to answer key questions, such as which farm jobs pose the highest risk to workers. There are no plans to add a testing requirement, Shah said. "We would like to do this in voluntary cooperation with farms and farm workers."

Federal officials said they were aware of anecdotal reports that some proponents of drinking raw milk are claiming that drinking H5N1-contaminated milk will boost immunity against the virus. Deeble said the USDA is not aware of any raw milk sold from any of the known outbreak farms. He added that the only way to protect against H5N1 infection from milk is to avoid drinking raw milk.

Even before the H5N1 outbreak in dairy cows was first detected in late March, federal health agencies have had a longstanding recommendation against drinking raw milk because of potential contamination with pathogens.

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USDA experiments suggest H5N1 not viable in properly cooked ground beef - University of Minnesota Twin Cities

(NewsNation) The Centers for Disease Control and Prevention launched a wastewater tracking dashboard Tuesday in an effort to monitor and stop the rapid spread of bird flu, which has been detected in cattle in nine states.

Over 40 cattle herds across the country have confirmed cases of the H5N1 virus, also called bird flu.

The CDC dashboard will track all influenza A viruses from 600 wastewater treatment sites around the country in order to help public health officials pinpoint where the viruses show up most aggressively.

Flu viruses that cause human disease circulate at very low levels during the summer months, so the presence of high levels of influenza A in wastewater during this time could be a reliable indicator that something unusual is going on in a particular area, reported STAT.

As of May 4, data from 189 of the agencys wastewater sampling sites showed that an influenza A virus had been detected at higher-than-average levels in sites, including some in Illinois and Alaska.

Concerns around the spread of bird flu have heightened as the virus becomes more widespread in dairy cows.

Avian influenza, commonly called bird flu, is an infection from a type of influenza virus that usually spreads in birds and other animals, according to the Cleveland Clinic.

The virus usually spreads in birds but can also infect humans if they come in contact with an infected animals body fluid, like spit, respiratory droplets or feces, the medical center said.

It can also be spread if a human breathes in small dust particles in animal habitats or gets it into their eyes, nose or mouth after touching animal body fluids. People who work with poultry, waterfowl and livestock are most vulnerable to catching the virus.

Its extremely rare for the virus to spread from one human to another, according to the Cleveland Clinic.

Researchers still dont know how the recent outbreak of bird flu spread to cattle, but the leading theory is that it has to do with milking machines that could be carrying the virus, Jenna Guthmiller, an assistant professor of immunology and microbiology at the University of Colorado School of Medicine, said in the universitys journal.

She said high levels of the virus have been found in the cows udders, and the infection appears restricted to dairy cows, which furthers this possibility.

Influenza A has never been recorded like this in cows before. Theres the occasional cow infected, but they are not a natural host for influenza A viruses, so this is really quite shocking to the field, she said.

Bird flu has been detected in 42 cattle herds in nine states as of Tuesday, according to federal data.

These states include Michigan, New Mexico, North Carolina, Kansas, Colorado, Idaho, Ohio, South Dakota and Texas.

Researchers at Stanford University and Emory University found high amounts of bird flu viral RNA in archived wastewater samples from three sites in northern Texas, reported STAT. The virus had been present at detectable levels since late February, one month before the state confirmed its first case of bird flu in cattle, the outlet reported.

There has been only one confirmed human case of bird flu this year, which came out of Texas.

The person had direct exposure to dairy cattle presumed to be infected with bird flu and experienced eye inflammation as their only symptom, state officials said.

The CDC is monitoring 260 people who have been exposed to infected dairy cows for flu-like symptoms. Thirty-three people have been tested for the virus, according to agency data.

The agency says the current risk of contracting the virus to the general public is low as these cases are rare in humans.

Right now, the H5N1 bird flu situation remains primarily an animal health issue. However, the CDC is watching this situation closely and taking routine preparedness and prevention measures in case this virus changes to pose a greater human health risk, it said.

According to the CDC, symptoms of bird flu in humans range from eye redness or mild flu-like upper respiratory symptoms to pneumonia, high fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches, fatigue, and shortness of breath or difficulty breathing.

Less common signs and symptoms include diarrhea, nausea, vomiting, or seizures, according to the agency.

The virus has been found in high levels in the raw unpasteurized milk of infected cows.

CDC officials warned last week that people who drink raw milk could theoretically become infected if the bird flu virus comes in contact with receptors in the nose, mouth and throat or if they inhale the virus into their lungs.

The Food and Drug Administration and the CDC both have long said that raw milk is one of the riskiest foods people can consume.

Raw milk can be contaminated with harmful germs that can make you very sick, the CDC warned.

But despite those warnings, sales of raw milk have risen.

Since March 25, when the bird flu virus was confirmed in cattle for the first time, weekly sales of raw cows milk have ticked up 21% to as much as 65% compared with the same periods a year ago, according to the market research firm NielsenIQ.

States have widely varying regulations regarding raw milk, with some allowing retail sales in stores and others allowing sales only at farms.

Viral remnants have been found in samples of milk sold in grocery stores, but the FDA said those products are safe to consume because pasteurization has been confirmed to kill the virus.

Bird flu is not transmissible by eating properly prepared and cooked poultry and eggs so these are safe to eat, the FDA has said.

The chance of infected poultry or eggs entering the food chain is extremely low because of the rapid onset of symptoms in poultry as well as the safeguards USDA has in place, which include testing of flocks, and Federal inspection programs, the agency said.

The Associated Press contributed to this story.

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Bird flu is spreading, but should you be worried? - NewsNation Now

Sales of raw milk appear to be on the rise, despite years of warnings about the health risks of drinking the unpasteurized products -- and an outbreak of bird flu in dairy cows.

Since March 25, when the bird flu virus was confirmed in U.S. cattle for the first time, weekly sales of raw cow's milk have ticked up 21% to as much as 65% compared with the same period a year ago, according to the market research firm NielsenIQ.

That runs counter to advice from the FDA and the CDC, which calls raw milk one of the "riskiest" foods people can consume.

"Raw milk can be contaminated with harmful germs that can make you very sick," the CDC says on its website.

As of Monday, at least 42 herds in nine states are known to have cows infected with the virus known as type A H5N1, federal officials said.

The virus has been found in high levels in the raw milk of infected cows. Viral remnants have been found in samples of milk sold in grocery stores, but the FDA said those products are safe to consume because pasteurization has been confirmed to kill the virus.

It's not yet known whether live virus can be transmitted to people who consume milk that hasn't been heat-treated.

But CDC officials warned last week that people who drink raw milk could theoretically become infected if the bird flu virus comes in contact with receptors in the nose, mouth, and throat or by inhaling virus into the lungs. There's also concern that if more people are exposed to the virus, it could mutate to spread more easily in people.

States have widely varying regulations regarding raw milk, with some allowing retail sales in stores and others allowing sales only at farms. Some states allow so-called cowshares, where people pay for milk from designated animals, and some allow consumption only by farm owners, employees, or "non-paying guests."

The NielsenIQ figures include grocery stores and other retail outlets. They show that raw milk products account for a small fraction of overall dairy sales. About 4,100 units of raw cow's milk and about 43,000 units of raw milk cheese were sold the week of May 5, for instance, according to NielsenIQ. That compares with about 66.5 million units of pasteurized cow's milk and about 62 million units of pasteurized cheese.

Still, testimonies to raw milk are trending on social media sites. And Mark McAfee, owner of Raw Farm USA in Fresno, California, says he can't keep his unpasteurized products in stock.

"People are seeking raw milk like crazy," he said, noting that no bird flu has been detected in his herds or in California. "Anything that the FDA tells our customers to do, they do the opposite."

The surge surprises Donald Schaffner, PhD, a Rutgers University food science professor who called the trend "absolutely stunning."

"Food safety experts like me are just simply left shaking their heads," he said.

From 1998 to 2018, the CDC documented more than 200 illness outbreaks traced to raw milk, which sickened more than 2,600 people and hospitalized more than 225.

Raw milk is far more likely than pasteurized milk to cause illnesses and hospitalizations linked to dangerous bacteria such as Campylobacter, Listeria, Salmonella, and Escherichia coli, research shows.

Before milk standards were adopted in 1924, about 25% of foodborne illnesses in the U.S. were related to dairy consumption, said Alex O'Brien, safety and quality coordinator for the Center for Dairy Research. Now, dairy products account for about 1% of such illnesses, he said.

"I liken drinking raw milk to playing Russian roulette," O'Brien said. The more times people consume it, the greater the chance they'll get sick, he added.

Despite the risks, about 4.4% of U.S. adults -- nearly 11 million people -- report that they drink raw milk at least once each year, and about 1% say they consume it each week, according to a 2022 FDA study.

Bonni Gilley, 75, of Fresno, said she has raised generations of her family on raw milk and unpasteurized cream and butter because she believes "it's so healthy" and lacks additives.

Reports of bird flu in dairy cattle have not made her think twice about drinking raw milk, Gilley said.

"If anything, it is accelerating my thoughts about raw milk," she said, partly because she doesn't trust government officials.

Such views are part of a larger problem of government mistrust and a rejection of expertise, said Matthew Motta, PhD, who studies health misinformation at Boston University.

"It's not that people are stupid or ignorant or that they don't know what the science is," he said. "They're motivated to reject it on the basis of partisanship, their political ideology, their religion, their cultural values."

CDC and FDA officials didn't respond to questions about the rising popularity of raw milk.

Motta suggested that the agencies should push back with social media posts extolling the health effects of pasteurized milk.

"Communicators need to make an effort to understand why people consume raw milk and try to meet them where they are," he said.

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There's Bird Flu in U.S. Dairy Cows. Raw Milk Drinkers Aren't Deterred. - Medpage Today

Influenza A viruses of various subtypes have a large reservoir in wild waterfowl. They are also known to infect and transmit among humans and in some other species or groups (domestic poultry, swine, horses, dogs, and bats). Influenza A virus subtypes currently circulating among people are A(H3N2) and A(H1N1) viruses. Examples of different influenza A virus subtypes currently circulating in animals include A(H1N1), A(H1N2), and A(H3N2) in pigs (different virus strains than those subtypes found in humans), A(H3N8) in horses, A(H3N2) in dogs, and A(H5N1) in wild water birds, domestic poultry, and dairy cattle. Influenza A viruses that can infect and regularly transmit among wild water birds and domestic poultry are called avian influenza viruses.

Influenza A viruses that typically circulate in wild aquatic birds can sometimes cause illness in another species (for example: pigs). Additionally, influenza A viruses from humans may be transmitted to pigs. For example, before 1998, only A(H1N1) viruses circulated widely in the U.S. pig population. However, in 1998, A(H3N2) viruses from humans were introduced into the pig population and caused widespread disease among pigs. More recently, avian influenza A viruses from birds have caused sporadic infections in mammals in the United States and in other countries and in United States dairy cattle.

Avian influenza A (bird flu) viruses may be transmitted from infected birds to other animals, and potentially to humans, in two main ways:

In birds, avian influenza A viruses infect the respiratory and gastrointestinal tract and are shed in feces. Direct infection of wild birds, poultry, and mammals can occur from exposure to saliva, mucous, or feces from infected birds. Avian influenza A virus infections among people arerare because currently circulating avian influenza A viruses do not have the ability to easily bind to receptors in the human upper respiratory tract.

However, human infections with avian influenza A viruses can happen when enough virus gets into a persons eyes, nose or mouth, or is inhaled. This can happen when virus is in the air (in droplets or possibly dust) and a person breathes it in, or when a person touches something that has virus on it and then touches their mouth, eyes or nose. Avian influenza A virusinfections in people happen most often after close, prolonged and unprotected (no gloves or other protective wear) contact with infected birds or other animals. People with close or prolonged contact with infected birds or animals or their contaminated environments are at greater risk of infection.

Influenza A viruses have eight separate gene segments. The segmented genome allows influenza A viruses from different species to mix genes (genetic reassortment) and create a new virus if influenza A viruses from two different species infect the same person or animal at the same time.

One possible way that virus reassortment could occur is if an animal or human were infected with a human influenza A virus and an avian influenza A virus at the same time. The new replicating viruses could reassort and produce a new influenza A virus that had some genes from the human virus and some genes from the avian virus. The resulting new virus might then be able to infect humans and spread easily from person to person, but it could have surface proteins (hemagglutinin and/or neuraminidase) different than those currently found in influenza viruses that routinely circulate in humans this could make it seem like a new influenza virus to people, one that had not been encountered before. Specifically, the term antigenic shift is applied to a new influenza A virus for which most people have little or no immune protection. If this new influenza A virus causes illness in people, is transmitted easily from person to person in a sustained manner, and if most people lack immunity to the new virus, an influenza pandemic can occur.

In the spring of 2009, a novel A(H1N1) virus emerged to infect people and quickly spread, causing an influenza pandemic. This virus had genes that were descended from viruses circulating in swine which were the result of reassortment between viruses from North American and Eurasian swine. It is also theoretically possible that the process of genetic reassortment could occur in an animal or person who is co-infected with an avian influenza A virus, or a swine influenza A virus, and a seasonal (human) influenza A virus. The genes of these viruses could reassort to create a new influenza A virus with a hemagglutinin and/or neuraminidase gene from the avian or swine influenza A virus and other genes from the seasonal influenza A virus. Viruses with such hemagglutinin and/or neuraminidase genes could potentially cause a pandemic if people lacked immunity against them, and the virus was able to spread easily from person to person in a sustained manner. Therefore, careful evaluation of influenza A viruses recovered from humans and animals who are not usually infected with avian influenza A viruses is important to identify genetic reassortment if it occurs.

Although it is unusual for people to get influenza A virus infections directly from animals, sporadic human infections and outbreaks caused by certain avian influenza A virusesand swine influenza A viruseshave occurred.

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Transmission of Bird Flu Viruses Between Animals and People - CDC

Bird flu, also known as the H5N1 virus, has infected cattle in nine states, according to data from the Centers for Disease Control and Prevention (CDC).

To track the spread of the disease, the CDC has begun reporting wastewater data.

Although it has affected millions of birds and other animals in the last 2 years, its risk to humans is still considered low. Just one person in the U.S. has developed H5N1 in recent months.

Since January 2022 in the U.S., the H5N1 virus has killed over 90 million birds across 48 states.

It also sporadically jumped into mammal species in the U.S., including mountain lions, bears, bobcats, coyotes, raccoons, minks, and skunks.

More recently, the virus has moved into a new host: cattle. Although cattle are less seriously affected than other species, this can make it harder to track where the disease is spreading.

Because the virus rarely kills cows, infected animals can continue to live among their herd, providing more opportunities for the virus to pass to other cattle and species.

In April 2024, the United States recorded its first cow-to-human transmission of H5N1 in a dairy farm worker in Texas. This is only the second human case of H5N1 to be identified in the U.S. ever; the first was in 2022.

So far, there has been no recorded human-to-human transmission of the virus.

Krzysztof Pyr, PhD, a professor of biological sciences and leader of the Virology Laboratory at the Malopolska Centre of Biotechnology at the Jagiellonian University in Poland said that the first human cases of H5N1 were discovered in the 1990s.

Since then, he explained, roughly 1,000 cases have been recorded in humans, approximately 50% of which were fatal.

Since 2020, we have a new subtype that is much more transmissible, causing a pandemic in birds with multiple outbreaks recorded worldwide, he said.

This includes infections in mammals, including marine mammals in South America, farmed foxes in Finland, and cats in Poland.

The CDC considers the threat posed to people by H5N1 to be low, but they are closely monitoring the outbreak. They have launched a new dashboard monitoring wastewater.

Their National Wastewater Surveillance System (NWSS) takes data from more than 600 sites across the U.S. and compares current levels of the virus with those from 2023.

According to the CDC, most wastewater monitoring cannot tell the difference between H5N1 and other types of influenza A viruses. However, detecting large differences between this years levels and the levels from 2023 is a signal that H5N1 is involved.

Compared with last years data, during the week ending the 4th of May, levels of influenza A viruses were above average in 10 sampling regions out of 230:

Levels of the virus were deemed high in one region:

To date, nine states have identified H5N1 outbreaks in cattle:

A recent paper from the Texas Epidemic Public Health Institute identified nine cities in Texas where H5N1 was detected in the wastewater between March 4th and April 25th. The paper is a pre-print and has yet to be published in a peer-reviewed journal.

The research used data from the Texas Wastewater Environmental Biomonitoring Network (TexWEB network) which focuses on the early detection of pathogens.

For approximately 2 years, TexWEB has been monitoring the wastewater of multiple municipalities across Texas, the study authors said in an emailed statement.

Using genetic information, the researchers can monitor the levels and sequence of hundreds or even thousands of viruses in a single sample.

The study authors told Healthline that, until March 2024, they had not identified any H5N1 viruses. However, After early March, they explained, we have seen H5N1 in multiple sites and we continue to see H5N1 up until the most recent sampling.

The Texas-based researchers told Healthline that data from wastewater acts as an early sentinel signal of where known or emerging viruses are present within the catchment area of a wastewater treatment plant.

They then pass this information to local and state public health departments, which can begin planning and increasing their surveillance efforts.

Although wastewater monitoring is a vital part of detecting emerging viral outbreaks, it does have certain limitations.

For instance, the researchers explain that TexWEB cannot identify where the virus is coming from, so it could be from wild birds, agriculture, food processing, or mammals, including humans.

At this point, there is no evidence for human-to-human transmission, and pasteurized milk has been shown to be safe, the researchers from Texas told Healthline.

However, they also said that TexWEB continues to monitor for emerging mutations that may increase virulence or transmissibility to mammalian hosts.

We asked Pyr whether the H5N1 virus could spark a new pandemic. Unfortunately, the answer is yes.

Luckily, he continued, for now, the virus does not thrive in the human body, and only a few cases have been reported globally. Can this change? Yes, it can, but we cannot predict when it will happen and how severe the disease caused by a new variant will be in humans.

We also asked what global health organizations should do to slow transmission. He answered our question with a question:

Are individual countries and politicians prepared to brace for the next threat and follow the advice given by international agencies? Are they ready to allow professional agencies to operate without political pressure?

While bird flu certainly is a serious threat, Pyr believes we should prepare for it, but we should not panic.

The H5N1 virus has infected millions of birds and other mammals. Recently, it has jumped into cattle in nine states. So far, there has only been one case of cattle-to-human transmission and no human-to-human transmission.

The CDC is closely monitoring the situation, and wastewater analysis is just one of their tools. Although we do not know the virus next move, for now, we do not need to worry.

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Where is Bird Flu Spreading in the US? - Healthline