Zoonotic Bird Flu News since 11 Feb till 16 Feb 2023

Bird Flu Is Infecting More Mammals. What Does That Mean for Us? [WebMD, 16 Feb 2023]

By Lucy Hicks

Feb. 16, 2023 ? A highly infectious strain of bird flu ? known as H5N1? is sweeping across the globe, devastating backyard flocks and commercial farms alike. While this virus mostly infects birds, growing reports of mammals infected with the virus have some experts worried. The main concern, they say, is as H5N1 continues to spread and multiply in different species, there are more opportunities for the virus to potentially gain mutations that could help it more easily infect humans.

“Just by the sheer numbers game, the more chances it has to infect humans or [other] mammals, the more chance you're going to get that rare event happening,” says Richard Webby, PhD, the director of the World Health Organization Collaborating Center for Studies on the Ecology of Influenza in Animals and Birds at St. Jude Children’s Hospital in Memphis.
Since May 2022, the U.S. Department of Agriculture has detected 121 mammals infected with the H5N1 virus, including red foxes, skunks, bears, and even seals. In October 2022, an outbreak at a mink farm in Spain resulted in the culling of over 51,000 animals, and earlier this month, Peru confirmed 585 sea lions had died from the virus in coastal nature preserves. While H5N1 infections have been detected in mammals over the past 25 years, “we’re certainly seeing an uptick in reported cases over the past 12 months,” Webby says.

The World Health Organization has stated that the risk to humans remains low, “but we cannot assume that will remain the case, and we must prepare for any change in the status quo,” WHO Director-General Tedros Adhanom Ghebreyesus, PhD, said at a news briefingthis month.

Human Infections Remain Rare
H5N1 infections in humans are rare. They mostly happen when someone has unprotected, direct exposure to birds infected with H5N1 or surfaces contaminated with the virus. Since 1997, there have been about 870 human cases reported to the WHO, with roughly half dying from the infection. Even if someone is infected with the virus, it is even rarer that the infection would spread to another human.

“H5N1 viruses currently circulating in wild birds and causing poultry outbreaks are well-adapted to spread among birds,” Tim Uyeki, MD, chief medical officer of the Influenza Division's Office of the Director at the CDC, said in an online Q&A. "However, these H5N1 bird flu viruses do not have the ability to easily bind to receptors in the upper respiratory tract of humans, or to transmit among people.”

Even with the record-breaking numbers of infected wild birds and poultry, human infections have become rarer in the last few years. Since the beginning of this century, it was not uncommon to have at least 30 to 40 recorded human H5N1 per year. Since 2021, there have been fewer than 10 infections reported around the world, according to the CDC.

More Spread in Mammals
H5N1 infections in wild mammals are not unheard of, though they are also rare events. Most of these cases likely occur when an animal eats an infected bird and is exposed to the virus.

Like in humans, these infections have been sporadic. But a report last month about an outbreak at a mink farm in Spain caused experts to worry, as the researchers suggested the virus may have spread by one mink infecting others. Minks are related to ferrets, which scientists use as an animal model for studying flu transmission.

“If we see something that transmits in mink, it’s not a stretch to think, ‘Maybe that is something that could also transmit in ferrets,’” Webby says. “We certainly would use transmission in ferrets as an alarm bell for human risk."

But so far, there is no evidence that the virus has picked up the ability to more easily infect humans, says William Schaffner, MD, a professor of infectious diseases at the Vanderbilt University Medical Center in Nashville.

“In fact, one of the reassuring things is in that mink farm in Spain, the people who work on the farm ? and had very close contact with those mink ? were all tested, and they were found to be negative,” he says. The minks were also very closely confined in cages ? which may have aided spread of the virus, he notes.

The more recent report of infections in sea lions had some people speculating online about possible spread of the virus among the animals, but these marine mammals may have also been exposed to birds infected with H5N1.

What is clear is that the virus is widespread, and is popping up in more and more animals, says Jennifer Nuzzo, DrPH, who heads the Pandemic Center at the Brown University School of Public Health in Providence, RI. Why that is happening is less obvious.

“Does that mean that [H5N1] has gained some fitness to mammals? What does that mean for the potential to infect humans? We just don't know,” she says.

Will Bird Flu Become the Next Pandemic?
Unfortunately, it’s not possible to predict what type of virus will cause the next pandemic. But the WHO Global Influenza Surveillance and Response System is already hard at work monitoring influenza strains around the world, Schaffner says .

“It’s like a radar system, trying to detect the enemy” as early as possible, he says. The network not only tracks infections in humans, but also in birds and other animals.

If the bird flu did begin to pose a real threat to the public, the U.S. already has a stockpile of bird flu vaccines.

“If we need them, they can be updated to the latest strain and immediately start to be manufactured,” Schaffner says.

While experts agree that the public’s risk for H5N1 is low, people should avoid contact with sick or dead wild birds, poultry, and wild animals. Do not eat uncooked or undercooked poultry, eggs, and other poultry products. It is safe to consume cooked poultry, poultry products, and eggs. Additional protective measures can be found on the CDC’s website.

Will bird flu spark the next pandemic? [Al Jazeera English, 16 Feb 2023]

By Ian Graber-Stiehl

A dramatic series of outbreaks is leading to concerns that a mutation could eventually hit humans and make COVID-19 seem mild.

It is a bloody trail: Avian flu has killed 15 million domestic birds and led to the culling of an unprecedented 193 million more since October 2021. The rampant virus has jumped from Europe and Asia to North America ? spreading shortly afterwards to bird populations in South and Central America.

And it is no longer restricted to birds. In the United States, the list of wild mammals either killed by or culled over avian influenza outbreaks is growing: grizzly bears in Nebraska and Montana, a red fox in Montana, six skunks and raccoons in Oregon, a Kodiak bear in Alaska and more.

Then in January, the World Health Organization (WHO) reported avian influenza in a young girl in Ecuador, the first such case ever in Latin America.

The story of these outbreaks is playing out like the opening shots of a pandemic movie ? with the scene-stealer from last October in Galicia, Spain. There, week by week, the mortality rate in a mink farm of 50,000 animals rose. Coming soon after another outbreak on the coast near Coruna, which left 27 seabirds sick or dead, avian influenza became a suspect. But sequencing revealed something more sinister: a mutation that had enabled the first-ever large-scale case of direct mammal-to-mammal transmission of bird flu.

There have only been five human bird flu cases in the last year. But past human cases of H5N1 avian influenza have had a 53 percent mortality, according to the WHO.

With the virus driving poultry shortages, killing droves of wild birds, and increasingly spilling over to mammals, the situation begs an overarching question: Could avian influenza evolve from an ecological disaster to a full-blown pandemic?

The short answer: For the moment, the risk of consistent bird flu transmissions to ? and between ? humans is low, according to scientists. But the fast-proliferating avian influenza infection is becoming a contender virus that could drive the next pandemic, one with a mortality rate that, if it spreads among humans, could make COVID-19 seem mild in comparison.

The mafia takes over
Avian influenza is actually a catch-all term for several strains of flu. The strain typically of concern is H5N1, each letter-number pair classifying the types of bonding proteins the virus has on the surface. But to truly understand H5N1 and contextualise its recent proliferation, one has to rewind to the late 1990s in China.

Speaking to Al Jazeera, Isabella Monne, a researcher with Italy’s Istituto Zooprofilattico Sperimentale delle Venezie who recently studied the mink outbreak in Galicia, noted that in 1996, H5N1 emerged in Chinese poultry production. The dense quarters and high populations favoured the emergence of more virulent strains, which jumped to wild bird populations in 2005.

This enabled the virus to spread further around Asia, Europe and the Middle East. Between 2003 and 2009, 468 human cases, primarily among poultry workers, resulted in 282 deaths. All the way through 2020, the number of host species and populations expanded exponentially. In all, the virus has killed 457 people in the last 20 years.

Then, in 2021, a front-running clade, or family, of H5N1 variants executed a mafia-esque takeover. By the end of 2021, the 2.3.4.4b clade was not only behind the vast majority of new cases in Europe, Asia, and the Middle East ? but had also jumped to Canada and the US. In 2022, the clan made its move to Central and South America, as well.

With the rise in outbreaks among poultry and wild birds, the increase in mammalian infections is not surprising, Kaitlin Sawatzki, a molecular virologist and animal surveillance coordinator with Tufts University, told Al Jazeera, describing the cases of spillover to mammals as individual incidents.

In birds, said Sawatzki, H5N1 is primarily a gastrointestinal infection that spreads through faeces.

In order to infect humans, said William Schaffner, a professor of medicine at Vanderbilt University’s Division of Infectious Diseases, the virus has to attach to receptors in the lungs ? receptors it lacks the ability to readily bond with. This forced adaptation to replicating in the lungs is why only poultry workers, who breathe in contaminated faecal dust, are typically infected. It is also why there had never been any large-scale cases of mammal-to-mammal transmission.
Until Galicia.

Minks, seals … humans?
According to Monne, following outbreaks of H5N1 in local bird populations, the Galician minks were most likely infected by contact with wild birds. As Monne herself helped uncover, the virus, in the dense population of mammalian hosts, developed a mutation in a gene called PB2.

While it is too early to know how much this contributed to the virus’ jump to minks, the PB2 mutation is known to increase the activity of an enzyme involved in viral replication in mammalian cells. This same mutation was also found in the strain of H1N1 swine flu that caused the 2009 pandemic, killing between 123,000 and 203,000 people worldwide.

“The mutation is a signal that this virus is trying to cross the barrier between species and adapt to the mammalian population,” Wenqing Zhang, the head of the World Health Organization (WHO) global influenza programme, told Al Jazeera.

Sawatzki believes the mink case is not necessarily an example of sustained transmission. The PB2 mutation was concerning but did not enable the virus to jump to humans or other species.

It was a dead end. No workers were infected. The minks were culled. The viral genome was sequenced and closely monitored.

More concerning for her is last year’s mass mortality of harbour seals off the US coast of Maine, as well as the more recent deaths of 2,500 seals off the coast of Dagestan, Russia.

Seals, she said, do not consume or get exposed to birds in quantities that would explain their high infection rates.

The implication: While it has yet to be confirmed, the seals may have an as-of-yet unidentified, alternative route of infection in a wild population that cannot be as easily monitored or culled.

No immunity
What does all of this mean for human health?

There are two potential ways humans can get an H5N1 respiratory infection: from animals or through person-to-person spread. The latter has only been suspected in an exceedingly small and largely unconfirmed handful of cases ? the most recent being from 10 years ago.

Furthermore, many of the recent bird flu headlines have been a story of successful monitoring. According to Zhang, the WHO has been tracking influenza outbreaks and viruses for more than 70 years. The organisation actively sequences variants that arise worldwide, tracking mutations of concern as they arise ? a capability that has only improved since the COVID-19 pandemic.

In the event of an outbreak, the WHO’s Pandemic Influenza Preparedness Framework mandates that a portion of any vaccines manufactured be donated to the organisation.

Likewise, stockpiles of existing antivirals would likely be relatively effective against an outbreak.

The threat of an H5N1 pandemic is not currently high. However, sooner or later, “there will be another influenza pandemic,” said Zhang. If the culprit of that pandemic is avian influenza, the consequences could be heavy.

The flip side of H5N1 viruses rarely infecting humans is the complete lack of immunity to the virus, Zhang said. So if the virus did evolve a way to reliably transmit from animals to humans, or worse yet, between humans, it would almost certainly mean a pandemic.

And there is a readily available mechanism for that evolution.

Influenza viruses have an eight-segment genome. Each segment can potentially swap genes with other influenza viruses inside a host, a process known as reassortment. This, Schaffner told Al Jazeera, makes minks and swine ? which can contract human, swine, and avian influenza viruses ? potential mixing bowls.

In, say, a pig simultaneously infected with a human-associated flu virus and avian influenza, this genetic reshuffling could result in a deadly new virus: one with H5N1’s virulence and mortality, and the receptors to precisely target humans.

Already a crisis
Developing an entirely new vaccine would likely take six to seven months, said Schaffner.

Existing stockpiles of antivirals, he said, would likely be consumed quickly. Thus, if the bird flu sweeping the world does lead to a pandemic among humans, it would probably fall on lockdown procedures to buy time for a vaccine.

“COVID has told us about the effects of behavioural interventions,” said Schaffner. During lockdowns, “while we were social distancing and all wearing masks, we had a season with almost no influenza”.

In the wake of COVID-19, people are practised at distancing procedures. Granted, another lockdown might be a hard sell to a weary public. Nevertheless, given the high mortality of historical H5N1 cases, Schaffner believes that once casualties start rising, people would likely toe the line ? slowing the spread of a potential avian influenza outbreak.

To be sure, there is only a slight risk of avian influenza targeting humans at the moment, but that comfort belies three concerning certainties. There will be an influenza emergency at some point; there are simply too many types of influenza, which mutate easily, and for which humans have limited resistance. Bird flu is a growing contender for the pandemic prize, threatening a mortality rate that far eclipses that of COVID-19. And in some ways, H5N1 is already a pandemic.

It is a pandemic on the beaches of Peru, where more than 10,000 pelicans have washed ashore in recent months. It is a pandemic in the empty nests of seabird colonies the world over. It is a pandemic for those who rely on both the money and food provided by poultry production, who had to cull millions of animals in the past 15 months.

Nutritionally, economically and ecologically, H5N1 is already a crisis. And despite the current low risks, the high-stakes threat of a bird flu pandemic among humans has the world at attention.

The Bird Flu Outbreak Has Taken an Ominous Turn [WIRED, 16 Feb 2023]

The avian flu has killed millions of chickens, decimated wild birds?and moved into mammals. Now the poultry industry needs new measures to stop its spread.

THIS WEEK, ARGENTINA and Uruguay declared national health emergencies following outbreaks of highly pathogenic avian influenza H5N1, the fast-moving virus that destroys poultry flocks and wild birds, and for decades has been feared as a possible spark for a pandemic among people. That makes 10 South American countries that have recently marked their first-ever encounter with the virus, including Peru?where more than 50,000 wild birds died last fall, and more than 600 sea lions in January. Combine the sea lion infections with the revelation that H5N1 flu invaded a mink farm in Spain in October, and health authorities must now confront the possibility that the unpredictable virus may have adapted to threaten other species.

To be clear, this does not yet include people. Although past decades have witnessed bird flu outbreaks that spread to humans, only two cases have been identified in the past 12 months: a Colorado adult last May, and a 9-year-old girl in Ecuador in January. (Neither died.) And there’s no evidence yet that the virus has been able to jump from newly infected mammals to people. But the fact that it was transmitted from bird to mammals, and then spread among them, indicates a disquieting trend.

According to the World Organization for Animal Health, at least 60 countries have recently experienced outbreaks of H5N1, which is named for two proteins found on the virus’s surface.

That includes the US, where 43 million laying hens were either killed by avian flu last year or slaughtered to prevent the disease from spreading. Those losses took out almost a third of the national flock of laying hens; according to the US Department of Agriculture, they cut into egg supplies so much that prices at the end of the year were 210 percent higher than at the end of 2021. Overall, the USDA estimates just under 58 million birds?mostly layers, turkeys, and backyard poultry?died or were killed in 2022, and another half-million so far this year.

The poultry industry is enormous. Just the US portion comprises more than 9 billion meat chickens and 216 million turkeys grown each year, plus 325 million laying hens; chicken is the most-consumed meat worldwide. That scale makes it difficult to put the losses from bird flu into context. But the ongoing epidemic has become the worst animal-disease outbreak in US history, as well as the largest poultry outbreak ever recorded in the UK, Europe, and Japan. And though surveillance is difficult, wildlife biologists say the damage to wild birds has been disastrous.

There may be little that can be done to protect wild birds; avian flu is spread by seasonally migrating waterfowl, which carry the virus without being harmed by it. But the poultry industry relies on a complex set of behaviors and building features, broadly called biosecurity, that it developed or reinforced after a catastrophic outbreak killed more than 50 million birds in 2015. Given the virus’s relentless advance, people who study the industry are beginning to ask whether biosecurity can ever be hardened enough to exclude avian flu?and if not, what has to change to keep birds and humans safe.

“We know that biosecurity can work and does work, but it’s a heroic effort, and it may not be sustainable given current building styles and current workforce,” says Carol Cardona, a veterinarian and professor of avian health at the University of Minnesota College of Veterinary Medicine. “The reason I say it can work is that companies that had [highly pathogenic avian flu] in 2015 had fewer cases in 2022. So they learned some lessons and changed some things?but very few of them kept it out completely.”

The relentless attack of H5N1 is important not just for its impact on poultry or wildlife, but for what it portends for people. Avian flu was long considered the animal disease most likely to break out into a global human pandemic, and even after the onslaught of SARS-CoV-2, many scientists still feel that way.

The H5N1 subtype first spilled from birds to humans in 1997 in Hong Kong. It sickened 18 people and killed six of them?small numbers, but a disturbing 33 percent mortality rate. Since then, variants of H5N1 have periodically infected people, causing 868 human cases through 2022 according to the World Health Organization, and 457 deaths. Those numbers represent a 52 percent mortality rate?but at the same time, an indication that the virus had not adapted enough to spread easily from person to person and ignite large outbreaks.

Still, scientists are always watching for the virus to find situations that would encourage those adaptations. For instance: Spanish and Italian scientists disclosed last month that in October 2022, an H5N1 variant infected minks on a fur farm in northwest Spain. The virus might have been passed to a single mink by a wild bird, or via chicken carcasses used for feed. But once on the farm, it made minute adaptations that allowed it to spread from one mink to another. To stop the outbreak, all the farm’s minks?almost 52,000?were killed.

That outbreak was unnerving, twice over. Not only had the virus begun adapting to mammals, but to a particular mammal that might have direct relevance for people. Minks belong to the same family as ferrets, which are already used by scientists for flu research because they develop symptoms in the same progression that humans do.

But there’s a third reason why the mink outbreak was notable, something that is so normal in animal agriculture that it mostly goes unnoticed. The Spanish farm was not a property where minks gamboled freely while they grew their fur. Instead, it was an intensive farm where the animals were confined in cages. Most of the poultry farms affected in the US have been intensive confinement farms also, though what that means differs by bird species: large metal barns for broilers, barns and sometimes interior cages for layers, and mesh-curtained sheds for turkeys.

Operating in confinement doesn’t necessarily make a farm more vulnerable to infection, but once a virus penetrates the premises, confinement ensures that very many animals are exposed at once. That puts a lot of animals at risk?some of the egg farms wiped out by flu last year lost more than 5 million birds?and it also gives the virus a plethora of hosts to mutate in. This drives people outside the poultry industry to suggest that if very large farms pose a risk of amplifying a virus, maybe making them smaller should be part of viral defense.
“When there’s public discussion of addressing zoonotic disease, it almost immediately turns to vaccination, preparedness, biosecurity?but no one discusses addressing the root cause,” says Jan Dutkiewicz, a political economist and visiting fellow at Harvard Law School’s Brooks McCormick Jr. Animal Law and Policy Clinic. “We would never have a debate about preventing cancer from tobacco products without talking about stopping smoking. Yet when it comes to zoonotic disease risk, there is a huge reticence to discuss curbing animal production.”

That might be an unthinkable proposal, given that Americans ate an estimated 1.45 billion wings during the Superbowl last Sunday?and that as a culture, we’re not inclined to ask many questions about how our food arrives at our plates. “Industrial animal production operates and maybe even depends on a distance between the consumer and the realities and violence of industrial animal production,” says Adam Sheingate, a professor of political science at Johns Hopkins University who studies food and agriculture policy. “Most people really prefer not to know how their food is produced.” Still, he points out, when disease risks from food become clear, other nations respond rapidly?such as when the UK changed cattle-farming practices after Creutzfeldt?Jakob disease, the human variant of bovine spongiform encephalopathy, or “mad cow disease,” killed 178 people in the mid-1990s.

“This is not to say we get rid of poultry,” says Andrew deCoriolis, executive director of Farm Forward, a nonprofit that works to improve farm animal welfare. “It's to say: We have to understand what are the factors that are the biggest risk drivers, and perhaps legislate changes to them. That could be moving farms out of flyways, it could be reducing the number of barns on a particular location, it could be reducing animal density within the barns.”

Dreadful though it is, it’s possible to construe the current outbreak as an opportunity to begin gathering big data about what makes poultry production so vulnerable. Precisely because the disease has spread so widely, data could reveal patterns that haven’t been visible before?whether affected farms use certain feed or water systems, for instance, or buy just-hatched birds from specific breeding lines, or are sited in particular landscape features or lie under the migration routes of identifiable birds. “There isn't a lot of research to show what are absolute best practices, because viruses are stochastic?you don't know exactly when you're going to get an introduction,” says Meghan Davis, a veterinarian and epidemiologist and associate professor at the Johns Hopkins Bloomberg School of Public Health.

After the 2015 outbreak, which up to that point was the worst poultry producers could imagine, the industry focused on identifying the human networks that made its farms vulnerable. Companies tried to control how visitors might unknowingly expose them to the virus: through sharing housing with workers from another property, or driving a truck from an infected farm onto a clean one, or carrying mail or even a cell phone that might have been contaminated. The extraordinary expansion of H5N1 flu into wild birds now may mean that producers also have to think about how the environment itself invites exposure. Wetlands attract ducks. Copses shelter raptors that pursue rodents that scavenge spilled grain. It’s an approach that concedes that biosecurity can never be perfect, and that a production system can never fully seal itself off from the world.

Avian flu hits Peru, killing thousands of sea birds and infecting some marine mammals [Mongabay.com, 16 Feb 2023]

by Tim Vernimmen

? H5N1, a highly pathogenic avian influenza virus carried generally by wild birds, has arrived in Latin America, causing unprecedented mortality in sea bird colonies along the west coast.
? The virus has killed tens of thousands of sea birds in Peru alone, including some species that are considered endangered in the country, and scientists worry other vulnerable species like the Andean condor might also become infected.
? Hundreds of sea lions and a dolphin have also been infected, which raises concerns regarding transmission to humans and is especially worrisome if it is confirmed that mammals can infect each other.
? The outbreaks also threaten Peru’s guano industry, which provides affordable fertilizer to many small-scale farmers in the region, and could expose people harvesting guano to H5N1.

Since late 2021, a highly pathogenic avian influenza virus of the type H5N1 has wreaked havoc on wild and captive birds across Asia, Africa, Europe and North America, killing millions. In November, it also arrived in Latin America, causing unprecedented mortality in sea bird colonies along the region’s west coast. “The first cases in Peru were confirmed on Nov. 13, 2022,” says Victor Gamarra-Toledo, an ornithologist at the Universidad Nacional de San Agustin de Arequipa in Peru. “By now, outbreaks have been reported in Ecuador, Colombia, Venezuela, Chile and Central American countries like Panama and Costa Rica.” The virus continues to spread southward: earlier in February, it was found in Ancud on the Isla Grande de Chiloe in Chile, about 1,125 kilometers (700 miles) south of Santiago.

“I’ve been working with Peruvian sea birds for 30 years,” says Carlos Zavalaga, an ornithologist at the Universidad Cientifica del Sur in Lima, “and I’ve never seen such massive mortality due to disease outbreaks.”

The occurrence of avian influenza in Peru is not unusual in itself, says Giancarlo Inga Diaz, wildlife veterinarian at the Peruvian National Service of Natural Areas Protected by the State (SERNANP), as variants of the virus have been found in the country before. “But in 2022, we’ve observed an unusual impact on wild populations of coastal sea birds. Our wildlife monitoring system recorded nearly 50,000 dead birds in eight protected areas [in Peru alone]. In the last week of January, we’ve observed a high mortality of resident birds in the Paracas National Reserve,” Inga Diaz tells Mongabay about the reserve located 265 km (165 mi) south of Lima.

Some of the heaviest impact seems to be on the islands just off Peru’s coast. “Authorities have banned researchers from entering the islands close to the coast where the main areas of mortality are,” says Zavalaga. “But about a month ago, we sent a drone with cameras from the coast to two of them, Pachacamac and Asia, and counted thousands of dead birds.” The most affected species, he says, are Peruvian pelicans (Pelecanus thagus), Peruvian boobies (Sula variegata) and Guanay cormorants (Leucocarbo bougainvilliorum). The pelicans and boobies have been designated as endangered by Peruvian authorities, while Guanay cormorants are considered to be near threatened by the IUCN. “We know that the numbers of the Peruvian pelicans in Peru never exceeded 100,000 individuals in the last 20 years,” says Zavalaga. “So the death of at least 20,000 of them is quite significant.”

The damage seems to go beyond birds. Hundreds of dead sea lions and a few dead fur seals have been discovered in several protected areas, including in Paracas National Reserve. Live sea lions there showed uncoordinated behaviors, a potential indication of infection of the nervous system, and had excessive mucus in their eyes, nose and mouth ? possible symptoms of avian flu, says Inga Diaz of SERNANP.

Still pending review, a recent analysis reveals that the sea lions had been infected by H5N1 ? but whether this was also what killed them has yet to be confirmed. A dead dolphin found in the north in the region of Piura was also shown to be infected with the virus. The deadly infections increase concerns that the virus may be able to spread from one mammal to another ? though that is also unconfirmed at the moment ? and may be able to infect people as well.

Farmers in trouble
The outbreak affecting the pelicans, cormorants and boobies is also affecting a particular sector of the local economy: guano harvesting. The birds’ dried, compacted excrement is a prized fertilizer in agriculture. “These three species produce around 86,000 tons of guano per year, which is roughly worth $50 million,” says biologist Daniel Plazas-Jimenez, from the Unitropico University in Colombia.

Plazas-Jimenez says the guano’s importance far exceeds its monetary value. “In Peru, most guano is sold to organic or traditional farmers, many from Indigenous communities, at a price that is low in comparison to that of inorganic fertilizers. In 2021, the Peruvian authorities planned to extract around 25,000 tons to provide for more than 40,000 families. Many people need guano to keep their organic certifications and often have few economic resources to buy other fertilizers. So this also affects their food security.”

“The guano industry in Peru is not industrial,” Zavalaga adds, “it’s very local. For example, last year only two islands in Peru were under guano harvesting. This year, I think they were planning [to harvest on] three or four [other islands].” He doubts whether the virus can survive in the harsh environment presented by the guano itself. “I’d be more afraid that live birds would pass the virus to humans, either on the islands or on the mainland beaches, where there are also dead animals. It’s summer now, so many people go there.”

In response to the outbreak, the Peruvian Ministry of Health has declared a 90-day state of emergency to prevent the virus from infecting people. According to Inga Diaz, measures include banning the collection of guano, advising against handling wild animals and using high-risk beaches, and training park rangers to monitor animal health.

Condors at risk
Local governments have sent teams wearing personal protective equipment to collect the carcasses found on beaches and bury them, says Zavalaga. He worries, however, that “on the islands, where the main colonies are found, there is a lack of adequate disposal of the carcasses.” As long as few people are allowed to go there, the risk of human infection is low. But in the meantime, dead and sick birds do pose an infection risk to other birds and mammals that share their habitat, and scavengers that feed on them.

That includes a very iconic and vulnerable one, the Andean condor (Vultur gryphus), says Gamarra-Toledo, who is studying how the condor’s feeding behavior exposes it to pollution.

“We are very concerned about the possible fatal consequences of this outbreak on this species.”

“We’ve found there is a population of Andean condors feeding mainly on sea lions, but sometimes also on dead pelicans,” says Sergio Lambertucci, an ornithologist at the Universidad Nacional del Comahue in Argentina. “Andean condors may be feeding on the coastline in the morning and roosting in the high mountains in the evening, 4,000 meters [13,120 feet] above sea level.” He also worries about turkey vultures, which roam more or less across the continent and might spread the disease even if it doesn’t kill them. “We are trapping them in Argentina now to find out.”

Bird migration is probably at the root of the outbreak, says Zavalaga, as the virus appears to have arrived with birds migrating from North America in spring, though the exact routes or culprits have not been identified. “Since the first report in mid-November, the deaths have not stopped,” he adds. “Animals are still dying on the islands. What kind of conservation measures are we going to take? I don’t see anything like a strategy for that yet.”

Gamarra-Toledo agrees that monitoring outbreaks and burying dead birds may not be enough to save them. “We should also reduce human impacts that negatively affect them ? environmental pollution, habitat loss and the overexploitation of resources ? so we can give these birds a better chance of survival.”

Citations:
Gamarra-Toledo, V., Plaza, P. I., Gutierrez, R., Luyo, P., Hernani, L., Angulo, F., & Lambertucci, S. A. (2023). Avian flu threatens Neotropical birds. Science, 379(6629), 246?246. https://doi.org/10.1126/science.adg2271
Wille, M., & Barr, I. G. (2022). Resurgence of avian influenza virus. Science, 376(6592), 459?460. https://doi.org/10.1126/science.abo1232
Gamarra-Toledo, V., Plaza, P. I., Inga, G., Gutierrez, R., Garcia-Tello, O., Valdivia-Ramirez, L.,
Huaman-Mendoza, D., Nieto-Navarrete, J. C., Ventura, S., & Lambertucci, S. A. (2023). First mass mortality of marine mammals caused by highly pathogenic influenza virus (H5n1) in south america [Preprint]. Pathology. https://doi.org/10.1101/2023.02.08.527769
Gamarra-Toledo, V., Plaza, P. I., Pena, Y. A., Bermejo, P. A., Lopez, J., Cano, G. L., Barreto, S., Caceres-Medina, S., & Lambertucci, S. A. (2023). High incidence of plastic debris in Andean condors from remote areas: Evidence for marine-terrestrial trophic transfer. Environmental Pollution, 317, 120742. https://doi.org/10.1016/j.envpol.2022.120742

Deadly new avian flu strain detected in wild mammal in California [San Francisco Chronicle, 16 Feb 2023]

By Jessica Flores

For the first time, the deadly new strain of avian influenza virus that has caused an unprecedented outbreak among birds in the Bay Area and statewide has been detected in a wild mammal in California, state wildlife officials announced.

Federal veterinary officials in January detected the highly pathogenic avian influenza strain, H5N1, in a bobcat after its remains were collected in Butte County in December and submitted for testing, the California Department of Fish and Wildlife said in a news release Wednesday.

“This is the first detection of the virus in a wild mammal in the state,” state officials said, adding that the deadly virus had been found in mammals ? including foxes, raccoons and skunks ? in other states and Canada.

Until now, only wild birds had been infected with the virus in California. H5N1 was first identified in wild birds in July 2022 and has been found in wild birds in 44 counties and domestic birds from 18 counties, officials said.

Avian influenza typically circulates among wild water birds and domestic poultry, and transmits to other birds through feces, saliva and respiratory droplets, according to the wildlife department.

But the current H5N1 strain has been infecting and killing a greater diversity of wild bird species than in past outbreaks, affecting raptors and scavengers such as turkey vultures and ravens, the release said.

Both mammalian and avian predators and scavengers may be exposed when they feed on infected birds, officials said.

The infected bobcat was wearing a GPS collar that alerts state officials when an animal stops moving, officials said. State biologists found it in an area where the virus had been recently detected in a turkey vulture, and began investigating the cause of death.

“Notwithstanding this detection, infection of wild mammals with avian influenza viruses appears to be relatively rare,” state officials said.

The disease causes neurological symptoms including tremors and seizures in birds. People who see a bird exhibiting strange behavior, experiencing tremors or appearing weak and lethargic should call a local animal control or wildlife center, officials say.

Because no vaccine or treatment exists, a bird that shows symptoms will not survive, experts say.

Transmission to people is considered low, but wildlife officials say people should not touch injured or dead birds or allow children or pets near them. Dead birds should be reported to the Department of Fish and Wildlife.

The Centers for Disease Control and Prevention urges people who are in contact with wildlife to take basic protective measures, such as wearing gloves and face masks, and washing their hands.

Mutating Bird Flu Virus Triggers Mass Die-Off Among Sea Lions | Weather.com [The Weather Channel, 15 Feb 2023]

Since the beginning of 2023, over 600 sea lions have been found dead or dying on Peruvian beaches. And we finally know the cause: the bird flu virus.

For the unversed, Peru has been facing a bird flu crisis since late last year, leading to the authorities declaring a 180-day health alert after finding three cases of highly contagious bird flu in pelicans in November 2022.

What followed was a massive event where 37,000 birds on a chicken farm had to be culled due to another outbreak in December.

Now, we know what you're thinking: what does avian influenza have to do with the death of mammals?

Before the sea lions died, the majestic carnivores were apparently suffering from agonising convulsions and were struggling to swim. With nothing like this having been observed before, a scientific team of Peruvian and Argentine researchers ran tests on the dead seals and have now confirmed that the mass mortality of the sea lions is due to the A(H5N1) bird flu virus that seems to have jumped from seabirds to these wild mammals.

Argentine biologist Sergio Lambertucci, one of the leaders of the investigation, suggested that the mammals were infected one after another ? either by living with sick birds or by feeding on their corpses.

However, addressing the strange episode on January 27 where a hundred dead sea lions were found floating in the waters of Isla Asia, Lambertucci said, "it wouldn't be strange if a few of them had eaten infected birds, but all of them?"

This has led researchers to consider a terrifying hypothesis suggesting that the virus had perhaps learned to spread from mammal to mammal. It would be the first time that this has occurred in nature.

While the pathogen has jumped from bird to mammal several times, even to people in exceptional cases, there had not been any cases of mammal-to-mammal transmission ? until now. And scientists fear that the virus could mutate and cause a deadly pandemic among humans.

"Given the large number of specimens found dead, it seems more likely that there was direct transmission between sea lions.

This is the second mass mortality episode to suggest that this virus can readily adapt to efficient mammal-to-mammal transmission. If it can occur in mink and sea lions, why wouldn't it happen in humans?" wondered Dutch veterinarian Thijs Kuiken from the Erasmus University Medical Center in Rotterdam.

Peruvian authorities have yet to monitor and conduct an epidemiological analysis to see what other species were affected by the H5N1 virus. But Peru's National Forest and Wildlife Service (SERFOR) has urged people and their pets to avoid contact with sea lions and seabirds on the beach.

Mountain lion near Gunnison found to have had bird flu ? The Crested Butte News [Crested Butte News, 15 Feb 2023]

by Mark Reaman

Be aware and protect your pets and yourself
While rare that the Highly Pathogenic Avian Influenza (HPAI), more commonly known as the bird flu, is discovered in mammals, count Gunnison County as a place to be marked with such a rare occurrence. A deceased mountain lion found near the city of Gunnison on January 15 was analyzed and determined to have HPAI. What that means is that it is still rare for mammals to contract the disease, but it does happen, and it could impact other wildlife and even pets and people in the area.

“I think the most important thing for people to remember is that this is first and foremost a disease among bird species. Wherever waterfowl are present, it is expected that HPAI is currently present,” said Southwest Region public information officer for Colorado Parks and Wildlife John Livingston. “While we have confirmed a few mammal cases, the concern here is still primarily with wild and domestic bird populations. Transmission to other wild animals most likely happens when they feed on wild birds that are sick or have died from HPAI. It’s also important to note that not every wild animal that does feed on a bird with HPAI will become sick or die.”

As far as humans, the CPW says HPAI strains can infect people very rarely but it can happen, so it is important to protect yourself. Avoid handling sick or dead birds and keep a distance from wildlife. Livingston said anyone handling birds should utilize personal protective equipment such as rubber or latex gloves. People should not eat wildlife found sick or dead.
HPAI has already killed thousands of wild birds in the U.S., including in Colorado. HPAI has been particularly contagious among domestic poultry. Three cases of this bird flu have now been confirmed in mammals in the state. They include the mountain lion found near Gunnison, a black bear in Huerfano County and a skunk from Weld County. Other deceased mammals are being tested. According to the CPW, symptoms of the disease include seizures or circling, general signs of illness including weakness or lack of responsiveness to human presence, and organ damage including encephalitis, hepatitis, and pneumonia.

The mountain lion, found near Gunnison in a place common for mountain lion habitat, had necrosis in the liver and broncho interstitial pneumonia which had been seen in domestic cats with HPAI. “Similar to many local species, mountain lions move through our communities on a regular basis as they travel between seasonal ranges throughout the year,” said CPW area wildlife manager Brandon Diamond of Gunnison. “It was only a matter of time before the first HPAI case was confirmed in Gunnison County based on known cases in adjacent counties.

While this is an interesting case study with the lion, it’s important to point out that HPAI has been documented previously in a variety of mammals from across the country. In Gunnison County, CPW routinely investigates reports of sick and injured wildlife and is always interested in hearing from the public if they encounter something that doesn’t look quite right.”

CPW is currently focusing surveillance by species, county and season. Once HPAI has been confirmed in a certain species and county, Livingston said the organization will not test additional birds of that species within that county until the next season. “We still appreciate reports of sick and dying birds to help inform us of the extent of an event, but we do not need to test every sick or dead bird,” he explained. “Testing of mammals is on a case by case basis determined by the wildlife officers and biologists who may find reason to send an animal in for testing.

“Mammalian cases across the country have included some species such as various bears, foxes, raccoons and bobcats, animals that are also found in Colorado,” emphasized Livingston. “It is important to remember that these cases are rare and this issue remains primarily a concern among wild and domestic bird populations. But it’s also important to keep pets away from wildlife at all times, and people should always keep their pets away from dead birds or other animal carcasses.”

Mass death of sea lions from bird flu suggests virus may be spreading between mammals in the wild [EL PAIS USA, 15 Feb 2023]

By MANUEL ANSEDE

Hundreds of dead or dying sea lions have washed up on the beaches of Peru since January.

Before dying, the animals ? majestic carnivores that can weigh up to 350 kilos ? had been suffering from agonizing convulsions and struggling to swim. Nothing like this had ever been observed in the region. A scientific team of Peruvian and Argentine researchers has now confirmed that the mass mortality of the sea lions is due to the A(H5N1) bird flu virus, which has jumped from seabirds to these wild mammals. Researchers are not ruling out a terrifying hypothesis: that the virus may have learned to spread from mammal to mammal, as it apparently did on a Spanish mink farm. It would be the first time that this has occurred in nature.

A total of 634 sea lions have been found dead in Peru. The leading theory is that the mammals were infected one by one, independently, by living with sick birds or eating their corpses, according to Argentine biologist Sergio Lambertucci, one of the leaders of the investigation.

The scientist, however, points to a concerning episode on January 27, when a hundred dead sea lions were found floating in the waters of Isla Asia, less than 60 miles (100 kilometers) south of Lima, the capital of Peru. “It wouldn’t be strange if a few of them had eaten infected birds, but all of them?” says Lambertucci, who is a researcher at the Biodiversity and Environment Research Institute in the Argentine city of San Carlos de Bariloche.

Dutch veterinarian Thijs Kuiken, an expert on emerging diseases, is also skeptical of the hypothesis that each sea lion was infected independently. “Given the large number of specimens found dead, it seems more likely that there was direct transmission between sea lions,” says Kuiken, from the Erasmus University Medical Center in Rotterdam. “It’s worrying,” he continues. “This is the second mass mortality episode to suggest that this virus can readily adapt to efficient mammal-to-mammal transmission. If it can occur in mink and sea lions, why wouldn’t it happen in humans?”

The A(H5N1) virus circulating around the world is a subtype of the highly pathogenic avian influenza. In Europe, it has caused the most devastating epidemic in history, with more than 50 million poultry slaughtered in just one year. The virus reached South America in late 2022, wreaking havoc in Peru, where it has killed more than 50,000 wild birds, mostly pelicans and boobies, according to data from Peruvian and Argentine scientists. The pathogen has jumped many times from bird to mammal, even to people in exceptional cases. In these case, however, there has not been mammal-to-mammal transmission. Scientists fear that the virus could mutate and cause a deadly pandemic among humans.

Thijs Kuiken lists another reason for concern: “There is video footage showing people in Peru trying to rescue sea lions potentially infected with the virus. This close contact increases the chances of the virus being transmitted from sea lions to humans.” The Peruvian government has asked citizens not to approach the wild animals. On January 3, a nine-year-old girl from Ecuador ? who was in contact with backyard poultry ? was admitted to the intensive care unit in critical condition after being infected with the A(H5) virus. According to the World Health Organization, the girl recovered from the virus. It was the first reported case of human infection by this strain of the avian influenza in Latin America.

In Peru, the 634 dead sea lions have been found on various beaches and protected areas in the country, such as the Paracas National Reserve. Researchers analyzed six specimens and found the virus in all of them. Autopsies of other specimens also detected traces of bird flu, i.e. hemorrhagic pneumonia in the lungs and hemorrhagic encephalitis in the brain.

Lambertucci points out that sea lions are very social animals, living in colonies that are often overcrowded. “If you have to think of wild species with the highest probability of mammal-to-mammal transmission, you would look to social animals such as sea lions, which live very close to each other,” says Lambertucci.

Before publishing their findings on the sea lions, the team of Peruvian and Argentine scientists had warned that the arrival of the bird flu virus posed a threat to protected birds in South America, including the Andean condor. Faced with the mass mortality of the sea lions, the researchers decided to urgently publish the first draft of their study on the mammals, without waiting to complete it. “We wanted to raise the alert as soon as possible due to the worrying nature of the situation. It is the first case of mass mortality of wild mammals in South America and could be the first event of intraspecies transmission in wild mammals in the world,” explains Lambertucci. The Argentine biologist stresses that they will need to carry out genetic studies of the virus to confirm or rule out their hypotheses ? work that will take weeks.

Peruvian ornithologist Victor Gamarra, co-author of the study, laments the slow reaction of the authorities. “We published the letter in Science precisely to draw the attention of Latin American governments to the need to do monitoring, an epidemiological analysis and to see what other species were affected,” explains Gamarra, from the National University of San Agustin de Arequipa. “There was an epidemiological silence, in which the public institutions stated that everything was under control. And suddenly these reports appeared of people finding dead sea lions all over the Peruvian coast. That is when the institutions began to take some samples,” says Gamarra. Among the Peruvian co-authors of the study, seven are members of the National Service of Natural State-Protected Areas.

In Spain last year, there were 37 outbreaks of the highly pathogenic avian influenza in poultry and another 138 cases in wild birds. In one of the outbreaks, on a farm with 150,000 laying hens in the city of Guadalajara, two workers became infected without developing symptoms. In October, the virus entered a fur farm with 52,000 American mink in Carral, a few minutes’ drive from the city of A Coruna. Mortality in this outbreak exceeded 4% in a single week. A study led by Montserrat Aguero, from the Spanish Ministry of Agriculture’s Central Veterinary Laboratory, suggested that the avian virus mutated at the mink farm and was then transmitted from mammal to mammal. The Spanish outbreak set off alarm bells around the world. Even the British doctor Jeremy Farrar, newly appointed scientific director of the World Health Organization, warned on social media of the risk of “a devastating flu pandemic.”

Bird flu isn't a direct threat to humans, experts say, but they're keeping a close eye on the virus [CNN, 14 Feb 2023]

By Jen Christensen

CNN ?
Avian flu has infected a record number of birds and some mammals across the United States, and scientists are keeping close watch.

World Health Organization Director General Tedros Adhanom Ghebreyesus said Thursday that the risk to humans remains low but added, “we cannot assume that will remain the case.”

As with the coronavirus that causes Covid-19 that is believed to have started in animals before spreading to humans, some animal viruses can mutate, jump species to make humans sick and spread quickly around the world.

But highly pathogenic avian influenza is no Covid-19. Scientists are reassuring the public that, with a few rare exceptions, the virus hasn’t made the jump to humans at a large enough scale to trigger an outbreak.

It has gone far beyond birds, though, and its recent spread among members of a separate species has some experts concerned about the way the virus is changing.

What is bird flu?
Avian flu is a type A influenza virus that originated in birds. The version that’s predominantly causing problems in the Americas and Europe is called H5N1. There are several subtypes, and H5N1 bird flu viruses commonly in circulation now are genetically different from earlier versions of the virus, according to the US Centers for Disease Control and Prevention.

Since late 2022, scientists have detected this virus in more than 100 species of wild birds like ducks, seagulls, geese, hawks and owls in the US.

Globally, this strain of the virus has actually been around a lot longer, said Richard Webby, an infectious disease researcher at St. Jude Children’s Research Hospital in Memphis, Tennessee, and director of WHO’s Collaborating Centre for Studies on the Ecology of Influenza in Animals and Birds.

“We saw the sort of great-great-granddad of the virus in the late 1990s in Southeast Asia, and we’ve been following its evolution and change ever since,” Webby said.

By the 2000s, it had spread into parts of Europe and Africa and then got carried into the rest of the world through infected migratory birds. It came to the Americas more recently, Webby said.

The first infection with this version of the virus was reported in wild birds in the US in January 2022, according to the CDC. The next month, the US Department of Agriculture announced an outbreak among turkeys in a commercial facility.

Studies have shown that bird flu may spread to songbirds, but the ones that typically gather at feeders ? such as cardinals, sparrows or blue jays ? and those you may see on the street like pigeons or crows do not typically carry bird flu viruses that would be a threat to humans, according to the CDC.

Ducks and geese can carry the virus without appearing sick. Poultry isn’t always so lucky.

Highly pathogenic avian influenza carries “very high mortality rates”among chickens and turkeys. The disease can affect multiple internal organs, causing death in 90% to 100% of chickens within 48 hours of infection, according to the CDC.

Because it can spread rapidly, farmers usually have to cull uninfected birds along with infected ones to prevent a wider outbreak. It is considered one of the largest known threats to domestic birds.

As of Wednesday, 6,111 cases had been detected in wild birds in all 50 states, the USDA says. The virus has affected more than 58.3 million poultry birds in 47 states, according to the CDC.
The sheer volume of cases means that the virus has a better chance of spilling over into other species, experts say.

More animals getting sick
Bird flu spreads through things like feces and saliva. It can also spread through contact with a contaminated surface.

The virus has infected many mammals in the US, mostly in the West and Midwest, as part of the latest outbreak.

In Alaska, cases have been reported among bears and foxes, according to the USDA. The virus has also been found in a bobcat in California, a skunk in Colorado, a raccoon in Washington, possums in Illinois and Iowa, a mountain lion and grizzly bear in Nebraska, seals in Maine and even a bottlenose dolphin in Florida.

In total, 17 non-bird species have been infected in 20 states.

Scientists say that all of those sick mammals probably caught the virus when they ate or otherwise interacted with infected birds.

But in a concerning development last fall, the virus seemed to spread between mammals ? perhaps for the first time ? at a mink farm in Spain, according to a study published in the journal Eurosurveillance.

The mink got bloody noses, developed tremors, lost their appetite and seemed depressed, the scientists said, and had to be killed to keep the threat in check.

The virus did not spread to humans who worked at the mink farm, but what worried scientists were the multiple mutations found in the virus that made it distinct from sequences found in birds. One mutation made it better at replicating in mammals, although it’s not clear whether the mutation was in the virus before it got to the farm.

“But it’s when it starts to spread from one mammal to the next mammal to the next mammal, it’s in those environments where we think it’s most likely that it will pick up these changes that allow us to switch hosts, and that’s why we get concerned,” Webby said.

A handful of human cases
There have been less than 10 known avian flu cases in humans since December 2021, and none has come from human-to-human transmission, the CDC says.

The most recent US case was in a person in Colorado who got sick after culling infected birds in April. The person reported being tired for a few days. They were isolated and treated with an antiviral, according to the CDC.

The agency said at the time that the threat to public health remained low, but it urged people who had any kind of exposure to birds to take precautions.

“People who’ve typically become ill are one of those individuals who have very intense interactions with wildlife either alive or dead,” said Dr. W. Ian Lipkin, director of the Center for Infection and Immunity and the John Snow professor of epidemiology at the Columbia University Mailman School of Public Health. “I wouldn’t say there’s another pandemic upon us, because it’s not. We’re not there.

“What we need to do right now is to watch very closely the way this spreads. We need to contain it in farms and wildlife as best we can,” he added.

How to stay safe
Although the threat to people is low, the CDC suggests avoiding direct contact with wild birds.
Webby says that if you need to handle a dead bird, such as removing it from a feeder, use gloves and a mask. Always wash your hands after touching birds or feeders.

It’s safe to eat poultry and eggs that are properly handled and cooked, the CDC said. Bird flu is not a foodborne illness, and the poultry industry is closely monitored and has strict health standards that include monitoring and controlling bird flu.

Always cook poultry and eggs to 165 degrees, a temperature that kills bacteria and viruses, including bird flu.

In the highly unlikely case that someone became sick, the CDC recommends getting treated right away. Most bird flu infections can be treated with currently available flu antiviral drugs, the agency says.

The US government also has a stockpile of vaccines, including against bird flu viruses, that could be used if this flu were ever to spread easily from person to person, the CDC says.

“The chances are not zero that you could get this, and anything you can do to further reduce that risk is a good thing,” Webby said. “But you probably really have to work hard to be infected with this virus.”

Fukushima City swan bird flu found to be highly pathogenic virus; bird surveillance strengthened in 10-kilometer radius [FNN Prime Online, 12 Feb 2023]

In Okabe, Fukushima City, Fukushima Prefecture, bird flu was detected on February 12 in a swan (Tundra swan) that was debilitated on a residential property.

Subsequent detailed analysis by the Ministry of the Environment revealed that what was detected was a highly pathogenic virus with a high fatality rate.

Fukushima Prefecture has already designated an area within a 10-kilometer radius of the discovery site as a "priority wild bird monitoring zone" and is stepping up surveillance.

This is the first confirmed case of avian influenza in wild birds in Fukushima Prefecture this fiscal year.

11 More Mammals Positive for Bird Flu [Precision Vaccinations, 11 Feb 2023]

by Robert Carlson

Mammal to mammal transmission of bird flu virus confirmed
UNITED STATES OF AMERICA (Precision Vaccinations)

Since the avian influenza outbreak began in the U.S. in early 2022, millions of birds have been detected with Highly Pathogenic Avian Influenza (HAPI) influenza type A viruses.

The Eurasian H5N1 strain initially appeared in North America in January 2022 and has impacted 47 states, leading to the loss of over 58.3 million various types of birds as of February 11, 2023.

And this HAPI outbreak has crossed over into mammals.

The United States Department of Agriculture's latest report indicates 121 HAPI H5N1 detections in mammals such as skunks, bears, raccoons, and foxes.

Expanding this list was a new report from the Colorado Parks and Wildlife (CPW), which detected this strain of HPAI in wild geese in Northeast Colorado in March of 2022.

The CPW announced on February 9, 2023, several cases of HPAI in free-ranging wildlife.
A black bear from Huerfano County was affected by the disease in October, a skunk from Weld County was found positive for the disease in November, and a mountain lion that died in Gunnison County was recently confirmed to have the disease.

Other similar suspected mammalian cases have been detected in the state, with confirmatory testing pending.

"The decision to humanely euthanize the animal by our wildlife officer was made following the abnormal behavior and knowledge that numerous infectious diseases cause neurological symptoms," said CPW Area Wildlife Manager Mike Brown in a press release.

"Extremely ill animals have difficulty moving and often act abnormally."

The Gunnison County mountain lion was found dead just outside of Gunnison city limits in 2023, in an area where mountain lion activity is commonplace.

The mountain lion had necrosis in the liver and bronchointerstitial pneumonia, which have been seen in domestic cats with HPAI.

CPW Area Wildlife Manager Brandon Diamond commented, "While this is an interesting case study with the lion, it's important to point out that HPAI has been documented previously in various mammals across the country."

The U.S. is not alone in reported bird flu cases in mammals.

Over the past year, various mammals in Mexico, Canada, South America, and the U.K. have also been infected by HAPI viruses.

And in Spain, a mink (Neovison vison) farm in Carral offers evidence that the H5N1 virus strain can spread between infected mammals.

While there are no vaccines to protect birds or mammals from this type of HAPI, there is one U.S. Food and Drug Administration (FDA) approved vaccine for people.

The Audenz monovalent, adjuvanted, cell-based inactivated influenza (H5N1) subunit vaccine is designed to protect people six months of age and older in the event of bird flu pandemics.

Audenz's initial FDA authorization was in January 2020, with a Supplemental authorization in 2021.

Bird flu and humans: Will avian influenza become a pandemic? [USA TODAY, 11 Feb 2023]

By Adrianna Rodriguez

As health officials continue to track and manage one of the largest bird flu outbreaks in recorded history, the virus is beginning to spill over into mammals ? including humans.

While human infections are still few and far between, health experts say it only takes one perfect combination of mutations for the virus to cause widespread transmission among the human population.

“There’s a tremendous amount of uncertainty about what is currently happening with bird flu and what might happen in the future,” said Dr. Jay Varma, director of Cornell University’s Center for Pandemic Prevention and Response.

Will avian influenza be the next human pandemic, and is the world ready? Here's what we know.

Tracking avian influenza: How widespread is it?
Bird flu has been on officials’ radar since the late 1990s, health experts say.

The strains causing widespread outbreak now ? avian influenza A (H5N1) 2.3.4.4b viruses ? first arose in 2020 and spread via migratory birds to Africa, Asia and Europe, according to the World Health Organization.

In late 2021, the H5N1 strains crossed to North America. The U.S. Department of Agriculture reports over 58 million chickens have been affected in 47 states. Nearly 6,200 wild birds have been infected including eagles, hawks, geese and ducks, as of this week.

“It seems like it spreads very easily among different bird species. You have so many different bird species that die off so rapidly from it,” said Varma, who is also the chief medical adviser at Kroll, a risk consulting firm.

Health experts, however, are more concerned with how the virus is affecting mammals. The USDA has detected H5N1 in various animals all over the country including skunks, foxes, raccoons, bears, mountain lions and dolphins, among others.

Most of these infections appear to be individual cases where the animal may have gotten sick from eating an infected bird, experts say.

Mammalian transmission: Why experts are concerned
However, two instances of possible mammalian transmission have rung alarm bells for health experts.

Between June and mid-July, over 150 dead seals in Maine were attributed to the bird flu, according to the National Oceanic and Atmospheric Administration. Although it’s possible the seals could have eaten infected birds, health experts say the large number of dead seals and their proximity to one another suggests mammal-to-mammal transmission.

Another outbreak on a Spanish mink farm suggests the virus may have adapted to mammal transmission. Scientific investigators were called when minks began showing signs of infection including loss of appetite, hypersalivation, depression, bloody snout and tremors.

After swabbing two infected animals, they determined the rest of the sickened minks had bird flu. It’s unclear exactly how many minks were infected, but researchers noted the animals began dying a few days after exhibiting symptoms.

More than 51,000 minks were killed to prevent further spread. Post-mortem examination of infected minks found pneumonia in their lungs. This also sounded the alarm for health experts, who say a mink's respiratory tract is closer to that of a human than bird.

"Ferrets, which are close relatives of mink, are our best animal model for human influenza infection," said Stephen Morse, a professor epidemiology at Columbia University's Mailman School of Public Health. "So, finding natural infection in mink seems a step closer to potentially infecting humans."

After sequencing the offending strain, researchers discovered the H5N1 had a slight mutation that doesn't exist in strain affecting birds. This "uncommon" mutation ? T271A in the PB2 gene ? was also seen in the swine flu H1N1 virus responsible for the 2009 pandemic that the CDC estimates caused more than 12,000 deaths in the U.S.

“We worry that this might be the prelude to the virus mutating in such a way that becomes a human epidemic," Varma said.

Can humans get bird flu? How does it spread to humans?
As of December, the WHO has reported six human infections from the circulating bird flu strains in China, Spain, the U.K., the U.S. and Vietnam.

All four cases in the U.S. and Europe were asymptomatic or mild infections, with fatigue reported as the only symptom. The patient in Vietnam developed severe disease but recovered, while the patient in China died.

“So far, the virus is difficult to transmit between people and the overwhelming majority of cases have been in people who have in direct and close contact with birds,” said Dr. Hana El Sahly, professor of molecular virology and microbiology at Baylor College of Medicine.

Bird flu tends to infect the lower respiratory tract, showing “it has a preference” in the lungs, said Dr. Katherine Baumgarten, medical director for infection control and prevention at Ochsner Health.

This suggests it could be less transmissible between humans because not as many viral particles are concentrated in the upper respiratory tract, like the nose or mouth, she said. But it also suggests the virus may be more capable of causing severe disease.

Can avian influenza cause a human pandemic?
Although researchers have identified certain mutations that may be associated with mammalian adaptation, health experts say these genes don’t seem to support widespread transmission between animals.

But that doesn’t mean it can’t happen. The more virus spreads, the more opportunities it gets to mutate and adapt.

“Flu viruses are always evolving, making them very unpredictable,” Morse said. “Could it spill over to the human population, and could it eventually become a pandemic? We really can’t say. It’s possible, but we don’t know how likely or, if it happens, when.”

Government agencies and international organizations track and study cases among birds, mammals and humans to detect any abnormalities that would be a cause for concern.

Health experts say it’s important to prepare for the possibility of an H5N1 pandemic because humans don’t have any immunity to the virus and it’s likely to cause severe disease.

Is the US ready for a bird flu pandemic?
In addition to surveillance, health experts say the U.S. needs vaccines, treatments and personal protective equipment to prevent spread.

The United States has antivirals for the seasonal influenza virus ? the most widely used is known by its brand name Tamiflu ? but health experts say it’s unclear if those will work against the circulating H5N1 strains.

A vaccine for H5N1 has been approved by the Food and Drug Administration for people 18 through 64 years who are at increased risk of exposure, according to an agency spokesperson.

The country has a small supply of vaccine, a spokesperson from the Health and Human Services told USA TODAY. The vaccine can be used to match against strains with pandemic potential and scale-up as needed, which health experts estimate could take up to six months.

About 100 public health laboratories across the country are also equipped with testing that can detect H5 viruses or novel influenza A viruses, according to the CDC.

Even if testing wasn't available, a CDC spokesperson told USA TODAY that most commercial testing for the seasonal flu would be able to detect a new influenza A virus should an outbreak occur.

How to protect yourself against the bird flu
To prevent infection, the CDC recommends avoiding unprotected contact with wild or domesticated birds that may look sick or have died. If contact can't be avoided, the agency recommends:
? Wearing personal protective equipment, like disposable gloves, boots, an N95 mask and eye protection.
? Avoid touching your mouth, nose or eyes during and after contact with birds or contaminated surfaces.
? Wash your hands with soap and water.
? Change your clothes after contact.