Zoonotic Bird Flu News from 17 Feb till 23 Feb 2023

Flu experts gather with H5N1 risk on the agenda [Reuters.com, 23 Feb 2023]

By Jennifer Rigby

LONDON, Feb 24 (Reuters) - The world's leading experts on influenza met this week to discuss the threat posed to humans by a strain of H5N1 avian flu that has caused record numbers of bird deaths around the world in recent months.

The group of scientists, regulators and vaccine manufacturers meets twice a year to decide which strain of seasonal flu to include in the vaccine for the coming winter season, in this case for the northern hemisphere.

It is also a chance to discuss the risk of animal viruses spilling over to humans and causing a pandemic. At this week's meeting, H5N1 clade 2.3.4.4b was a key topic, the World Health Organization (WHO) and global flu experts told Reuters.

"We are more prepared (than for COVID), but even if we are more prepared, we are not yet prepared enough," Sylvie Briand, WHO director of global infectious hazard preparedness, said ahead of the meeting. "We need to really continue the efforts for a flu pandemic."

Briand in a briefing after the meeting said that the recent rise in cases in birds and mammals was "worrying" and that the agency was working with Cambodia after two confirmed human cases of H5N1 were found in one family there. They are trying to determine if the family members were exposed to the virus through the environment - such as exposure to birds or other mammals - or if there was human-to-human transmission.

Disease experts have raised the idea that the virus would need to change for it to be conducive to human transmission.

Experts have been tracking H5N1 clade 2.3.4.4b since it emerged in 2020 and recent reports of mass deaths in infected mammals from seals to bears, as well as potential mammal-to-mammal transmission on a Spanish mink farm last year, have raised concern.

However, there have been very few human cases, and the WHO currently assesses the threat to humans as low.

"This is a natural experiment playing out in front of us, and I don't think we are complacent," said Nicola Lewis, director of the WHO Collaborating Centre on Influenza at the Crick Institute in London. Speaking before the meeting, she said it would include assessments of the situation worldwide.

Experts also discussed potential vaccine development.

WHO-affiliated labs already hold two flu virus strains that are closely related to the circulating H5N1 virus, which could be used by vaccine manufacturers to create a human vaccine if needed. One of them was added after the previous WHO flu meeting in September 2022, and the experts decided at this week's meeting to add another subtype that more closely matches the virus spreading among animals.

A number of companies that produce seasonal flu vaccines can also make pandemic flu vaccines. For example, GSK and CSL Seqirus are already working with the United States Biomedical Advanced Research and Develop

ment Authority (BARDA) to test shots based on one of the closely related strains.

Having these strains ready could save about two months in the development of a vaccine, said the WHO's Briand. But getting enough vaccine developed quickly would still remain a challenge in a pandemic situation, the experts said.

Bird flu death in Cambodia: How worried should we be about H5N1 spilling over into humans? [Euronews, 24 Feb 2023]

By Giulia Carbonaro

An 11-year-old girl has died from bird flu in Cambodia’s first known human case of H5N1 since 2014, according to health officials, who said her father had also been infected.

Bird flu, also known as avian influenza, normally spreads in poultry and wasn’t deemed a threat to people until a 1997 outbreak in Hong Kong.

Most human cases around the world have involved direct contact with infected poultry, but cases have recently been recorded in various mammals, reviving fears the virus could mutate to spread more easily to humans.

WHO concerns about bird flu
The girl from the rural southeastern province of Prey Veng became ill on February 16 and was sent to hospital in the capital Phnom Penh. She was diagnosed on Wednesday after suffering a fever up to 39 C with coughing and throat pain and died shortly afterward, the health ministry said.

Symptoms of H5N1 infection are similar to that of other flus, including cough, aches and fever. In serious cases, patients can develop life-threatening pneumonia.

Earlier this month, WHO Director-General Tedros Adhanom Ghebreyesus voiced concern about bird flu infections in mammals including minks, otters, foxes and sea lions.

“H5N1 has spread widely in wild birds and poultry for 25 years, but the recent spillover to mammals needs to be monitored closely,” he warned.

He advised people not to touch dead or sick wild animals and called on countries to strengthen their surveillance of settings where people and animals interact.

The WHO still assesses the risk from bird flu to humans as low, he added.

“But we cannot assume that will remain the case, and we must prepare for any change in the status quo,” he said.

In a very concrete way, the spread of what scientists have confirmed is the world's worst bird flu outbreak - which has now been unfolding for over a year - is already affecting us.

The disease is one of the contributing factors making both poultry meat and eggs more expensive, together with the lingering impact of COVID-related disruptions and the Russian invasion of Ukraine.

Overall, the outbreak is exacerbating the cost of living crisis, disrupting food supply chains and forcing the culling of millions of poultry destined to end up on the shelves of our grocery retailers.

Is bird flu getting worse?
One of the biggest concerns for humans is also that the rampaging bird flu could enter territories previously uncharted - including mutating into the next pandemic.

"The situation is unprecedented. Last winter we had the worst outbreak of highly pathogenic avian influenza in the UK. This year is on track to equal or beat that", Professor Paul Digard, Chair of Virology at the University of Edinburgh, told Euronews Next.

"It's unprecedented because of the number of those infection numbers that have occurred in poultry and because of the infections that we've seen in wild birds as well, particularly seabirds", he continued.

"The other thing that's changed is that normally, in northern Europe and the UK, we get sporadic incursions of high pathogenic avian flu in the winter, but then they disappear over the summer.

“Last summer, it never entirely went away, it died down quite a lot, but it never fully went away. So the virus has changed its behaviour in ways that we've not seen before in this part of the world".

While bird flu - or highly pathogenic avian influenza, to be exact - has been around for at least 200 years and probably more, said Digard, outbreaks have become more common.

"The numbers [of outbreaks] have picked up since the 1980s, and then everything changed in 1996-97 when the ancestor of the current virus appeared in Hong Kong," Digard said.

"And that virus was different from all the previous ones in that it could survive in wild birds as a sort of a long-term infection, and that gave it the ability to spread around the world so that that virus or descendants of it have been with us for the last 25 years.

"And the number of outbreaks of that lineage of the virus has been very large indeed. The numbers are higher than they've been in the past. That's probably fair to say".

What's the risk to humans?
"There is a risk to human health, but at the moment I would say it's low", said Digard.

During the 1997 outbreak, 18 people got infected with bird flu, and six died.

"It was a rare infection in humans, but when it did happen, it had roughly a 50 per cent case fatality rate", said Digard.

Until at least the early to mid-2010s, the situation stayed the same, said Digard, with very rare cases of human infections but causing severe illness in those who contracted the virus.

"Since then the virus has changed, and from the human perspective, it has changed for the better", said Digard. "It seems to be causing far fewer human infections, and when it does infect people, it seems to cause milder disease in most people".

So, the risk to human health is lower than it has been in the past, and there's no need to panic.

"This lineage of the virus has been with us for 25 years and in that time, although it's been able to infect people, it's never shown any signs of really evolving the ability to transmit from person to person, which is what you would need for a major outbreak in humans," said Digard.
But chances are that the virus might change in the future.

Health authorities in the UK are now modelling scenarios to assess what might happen should the virus mutate and spread more aggressively among humans, sparking a new health crisis similar to the COVID-19 pandemic.

"Like COVID, [the bird flu virus] is permanently changing, it never stays still," said Digard.

"You can't say it will never adapt, it'll never change in a way that will cause the next pandemic, but I think it’s very low-risk at the moment," he continued.

"I don't think it's low-risk that we'll get another flu pandemic; I think that's the case of when not if. But my guess would be it's not going to be this strain. It'll be something else that catches us by surprise".

After the outbreak of COVID-19, which is believed to have spilled over from a yet unidentified animal into humans, experts warn that the next pandemic will likely come from another zoonotic disease like coronavirus.

"This is a problem that's grown over the years. But we have become better able to try and head off some of these problems," said Digard.

We have found a way to create vaccines against the flu - including the H5 virus strain - and we are able to produce them on a large scale.

Researchers are getting better at the "social science's side of things, trying to understand the factors that make zoonotic diseases more of a threat, as you get larger numbers of people and more contact between people and food animals and food animals and wild animals," said Digard.

In this context, the way we farm animals for the meat and dairy market is of crucial importance to avoid virus spillovers.

"We can change your security procedures, you can change the way you design farms to reduce the chance of those transmission events happening in the first place".

Human Bird Flu Cases Investigated in Cambodia [The New York Times, 24 Feb 2023]

By Apoorva Mandavilli and Emily Anthes

Two family members were infected with H5N1; the daughter died. Eleven contacts, some with symptoms, have tested negative, according to the W.H.O.

After a father and daughter were diagnosed with bird flu, officials in Cambodia scrambled to test nearly a dozen of their contacts for infection the H5N1 virus, which has been causing mass die-offs of birds worldwide. The daughter, an 11-year-old, has died, but the World Health Organization said on Friday that 11 contacts have so far tested negative for the infection.

Why the concern? While hundreds of human cases have occurred over the years, scientists have become increasingly concerned that the virus one day may become adapted to people.

Any evidence of human-to-human transmission would accelerate worries that a new pandemic could be on the way.

Most experts believe that the cases in Cambodia were likely caused by direct exposure to infected birds. At the moment, the risk to most people remains low, they say.

Cambodia has reported two cases of bird flu infection in people, a father and daughter in a village in Prey Veng Province. The 11-year-old girl died earlier this week.

The cases, the first reported in Cambodia since 2014, raised fears that the virus had acquired the ability to spread among people and may trigger another pandemic. But the World Health Organization said on Friday that 11 contacts of the girl, four of whom have flulike symptoms, had tested negative for infection with the H5N1 flu virus.

The 49-year-old father who has tested positive was not showing any symptoms, according to the Health Ministry. The W.H.O. is working closely with the Cambodian government to determine whether the father and daughter both caught the virus from direct contact with infected birds — the most likely possibility — or whether they infected each other.

Experts noted that there had been hundreds of sporadic cases of H5N1 infection in people since the virus was first identified and that there was no evidence that it had become adapted to humans.

Transmission among people is “very, very rare, versus a common source of infection,” said Richard Webby, a bird flu expert at St. Jude Children’s Research Hospital in Memphis and an adviser to the W.H.O.

But people should take care to avoid contact with wild birds that may be infected, Dr. Webby said.

“The risks from this virus to your average person on the street right now is very low, but it’s not zero,” he said. “And that’s primarily because there’s just so many more infected birds around right now.”

Bird flu, or avian influenza, is a group of flu viruses that are primarily adapted to birds. The particular virus in these new cases, called H5N1, was first identified in 1996 in geese in China, and in people in Hong Kong in 1997.

Since then, there have been nearly a thousand cases in people in 21 countries, but a vast majority have resulted from prolonged, direct contact with birds. H5N1 does not yet seem to have adapted to spread efficiently among people.

“At the end of the day, this is a continuum of the same outbreak that started back in 1996,” said Dr. Malik Peiris, chief of virology at the University of Hong Kong, who has helped oversee responses to several bird flu outbreaks in Southeast Asia. “Really, it never went away.”

H5N1 is typically carried by aquatic birds, such as ducks, that can transmit the virus to domestic poultry via feces, saliva or other secretions.

The current version of the virus has been unusually widespread, causing the largest ever bird outbreaks in Europe and in the United States, affecting 58 million farmed birds in the latter. It is now considered endemic in several countries in Asia and Europe, according to Dr. Webby.

The virus has taken a heavy toll on wild birds too, triggering mass die-offs, and it has been spilling over into mammals, especially scavengers, like foxes, that might feed on infected carcasses.

Any reports of infection in people warrant investigation to confirm that H5N1 has not yet adapted itself to human-to-human transmission. There have been six other cases of H5N1 reported in people since September, according to the W.H.O. The death of the 11-year-old girl this week is Cambodia’s first bird flu death since 2014.

Experts have been closely monitoring H5N1, especially since an outbreak on a Spanish mink farm in October suggested that the virus could spread efficiently among some mammals.

Samples of the virus isolated from the mink carried a genetic mutation that is known to help flu replicate better in mammals.

No human infections were detected. But a mink-adapted version of the virus might be one step closer to efficient transmission among people.

If the version of H5N1 identified in Cambodia were found to be closer to the one seen in Spain than to those in previous Asian outbreaks, scientists would be concerned, Dr. Peiris said. “It is important to try to understand exactly what has gone on” in Cambodia, he added.

The W.H.O. is “updating a bank of vaccine candidate viruses that are suitable for manufacturing, should it be needed,” the agency said in a statement. W.H.O. is also providing antiviral drugs from an available stockpile.

How will scientists know if H5N1 begins spreading among people?
Genetic analysis can reveal whether H5N1 has acquired mutations that help it spread among people.

“That should give us a good hint as to whether or not the virus has really jumped one step further,” said Dr. Shayan Sharif, an avian immunologist at the Ontario Veterinary College at the University of Guelph in Canada.

But it will be more difficult to determine how the two family members were infected in Cambodia. That’s because H5N1 samples from the father and daughter are likely to be nearly identical regardless of whether the virus was acquired from a person or from the same infected birds, Dr. Webby said.

“If both of them were infected from the same set of chickens, they are going to be infected with very similar viruses,” he said. It may be more informative for scientists to chart the path of the virus by examining the nature of the contact among infected people.

Can we prevent the virus from spilling over into humans?
The virus poses the biggest risk to people who are in direct contact with birds, such as poultry farmers. Security measures on farms and poultry processing plants, including the use of personal protective equipment by workers, can help reduce the risks of infection.

To contain local outbreaks, infected flocks are generally culled and farms are put under quarantine. But the virus is now so widespread in birds that experts are beginning to consider whether broader measures, such as the vaccination of poultry, might be needed.

Vaccination has not traditionally been used to control avian influenza in poultry in the United States or Europe. But officials are rethinking that stance, and trials of bird flu vaccines are underway.

“I don’t really think that we should panic at the moment,” Dr. Sharif said. But “as we see all of these various different bits and pieces of the puzzle coming together,” he said, “I believe we need to get really seriously ready for an emergency.”

WHO says avian flu cases in humans ‘worrying’ after girl’s death in Cambodia [The Guardian, 24 Feb 2023]

By George Monbiot

The discovery of two cases of bird flu within the same family in Cambodiahas highlighted the concern over potential human-to-human spread of the virus, although experts have stressed the risk remains low.

On Thursday, Cambodian authorities reported an 11-year-old girl from Prey Veng province had died from H5N1, with subsequent testing of 12 of her contacts revealing that her father also had the virus.

Be warned: the next deadly pandemic is not inevitable, but all the elements are in place

However, it remains unclear whether the two cases were down to human-to-human transmission, or the result of both father and daughter having had close contact with animals infected with H5N1.

The World Health Organization said on Friday that increasing reports of bird flu in humans are “worrying”.

Sylvie Briand, the WHO’s epidemic and pandemic preparedness and prevention director, said the UN agency was in close contact with the Cambodian authorities for updates on the case and on tests of other people who had been in contact with the girl.

“So far, it is too early to know if it’s human-to-human transmission or exposure to the same environmental conditions,” Briand told a virtual press conference hosted in Geneva.

“The global H5N1 situation is worrying given the wide spread of the virus in birds around the world and the increasing reports of cases in mammals including humans,” she added. “WHO takes the risk from this virus seriously and urges heightened vigilance from all countries.”

Earlier this month, the WHO assessed the risk to humans from H5N1 bird flu as low, although its director-general, Dr Tedros Adhanom Ghebreyesus, said the recent spillover to mammals needs to be monitored closely.

“Since H5N1 first emerged in 1996, we have only seen rare and non-sustained transmission of H5N1 to and between humans. But we cannot assume that will remain the case, and we must prepare for any change in the status quo,” he said.

H5N1 –– often called bird flu– – is a highly infectious strain of avian influenza A virus that can cause severe respiratory disease and death in birds. While it has caused outbreaks before, the current epidemic has led to the devastation of avian populations around the world, including wild birds and commercial poultry.

The virus has also been known to jump from birds to other animals as well as humans, with the WHO noting that sporadic human cases are not unexpected as a result of exposure to infected poultry or contaminated environments.

Data from the WHO reveals that from January 2003 to 5 January 2023, there have been 868 cases of human infection with avian influenza A(H5N1) virus around the world, 457 of which were fatal. However, only six of these cases, and two deaths, occurred since the start of 2021.

Prof James Wood, head of the department of veterinary medicine at Cambridge University, said that despite the current epidemic in birds, there is no sign of a dramatic rise in cases or deaths in humans.

“There has been massive global challenge of wild and domestic birds with the current H5N1 avian influenza virus over the last few months and years, which will have exposed many humans; despite this, what is remarkable is how few people have been infected,” he said.

“Tragic though this case in Cambodia is, we expect there to be some cases of clinical disease with such a widespread infection. Clearly the virus needs careful monitoring and surveillance to check that it has not mutated or recombined, but the limited numbers of cases of human disease have not increased markedly and this one case in itself does not signal the global situation has suddenly changed,” he added.

Jonathan Ball, professor of molecular virology at the University of Nottingham, added the likelihood of onward human-to-human transmission is very low, but that it is important to monitor circulation of flu in bird and mammal populations and do everything possible to reduce the number of infections seen.

“It also highlights why efforts to develop next-generation cross-reactive vaccines are so important,” he said.

Bird flu kills 11-year-old girl in Cambodia, officials say [ABC News, 23 Feb 2023]

By SOPHENG CHEANG

An 11-year-old girl in Cambodia has died from bird flu in the country’s first known human H5N1 infection since 2014

PHNOM PENH, Cambodia -- An 11-year-old girl in Cambodia has died from bird flu in the country's first known human H5N1 infection since 2014, healthofficials said.

Bird flu, also known as avian influenza, normally spreads in poultry and wasn’t deemed a threat to people until a 1997 outbreak among visitors to live poultry markets in Hong Kong. Most human cases worldwide have involved direct contact with infected poultry, but concerns have arisen recently about infections in a variety of mammals and the possibility the virus could evolve to spread more easily between people.

The girl from the rural southeastern province of Prey Veng became ill Feb. 16 and was sent to be treated at hospital in the capital, Phnom Penh. She was diagnosed Wednesday after suffering a fever up to 39 Celsius (102 Fahrenheit) with coughing and throat pain and died shortly afterward, the Health Ministry said in a statement Wednesday night.

Health officials have taken samples from a dead wild bird at a conservation area near the girl's home, the ministry said in another statement Thursday. It said teams in the area would also warn residents about touching dead and sick birds.

Cambodian Health Minister Mam Bunheng warned that bird flu poses an especially high risk to children who may be feeding or collecting eggs from domesticated poultry, playing with the birds or cleaning their cages.

Symptoms of H5N1 infection are similar to that of other flus, including cough, aches and fever, and in serious cases, patients can develop life-threatening pneumonia.

Cambodia had 56 human cases of H5N1 from 2003 through 2014 and 37 of them were fatal, according to the World Health Organization.

Globally, about 870 human infections and 457 deaths have been reported to the WHO in 21 countries. But the pace has slowed, and there have been about 170 infections and 50 deaths in the last seven years.

WHO Director-General Tedros Adhanom Ghebreyesus earlier this month expressed concern about avian influenza infections in mammals including minks, otters, foxes and sea lions.

“H5N1 has spread widely in wild birds and poultry for 25 years, but the recent spillover to mammals needs to be monitored closely,” he warned.

In January, a 9-year-old girl in Ecuador became the first reported case of human infection in Latin America and the Caribbean. She was treated with antiviral medicine.

Tedros said earlier this month that the WHO still assesses the risk from bird flu to humans as low.

“But we cannot assume that will remain the case, and we must prepare for any change in the status quo,” he said. He advised for people not to touch dead or sick wild animals and for countries to strengthen their surveillance of settings where people and animals interact.

New pandemic fears as girl dies as deadly bird flu jumps from mammals to humans [Daily Star, 23 Feb 2023]

By Adam Cailler

Scientists had predicted that a new pandemic could be on the way after bird flu jumped to mammals, and it has now shockingly killed an 11-year-old girl in Cambodia

A girl has died from bird flu, confirming the worst fears of scientists who predicted it could jump from mammals to humans just last month.

The sad death of the 11-year-old was reported in Cambodia earlier today (Thursday, February 23).

The girl first became ill just six days before her death, and suffered from a fever, cough and sore throat.

As a result, the World Health Organization has said: "The recent spillover to mammals needs to be monitored closely."

The news comes just a weeks after we reported that it was found that a deadly strain of the avian bird flu had mutated and can now impact mammals.

Just a year after most of the world came out of a pandemic, news of the new strain of bird flu has sparked fears of a new one after 50 million poultry were slaughtered in Europe in the space of one year.

And scientists had found that the avian flu had been transmitted from wild birds to a group of mink on a farm in the Spanish city of La Coruna.

The study, published on top infectious disease surveillance website Euro Surveillance, stated that the outbreak happened in Spain in October 2022.

It claimed that the coronavirus was passed from farmed minks to humans during the pandemic – and it can happen against with the new strain of avian flu, labelled as HPAI H5N1.

The experts state: “Given the concerns caused by the susceptibility of minks to emerging viruses such as HPAI H5N1 viruses and SARS-CoV-2, it is necessary to strengthen the culture of biosafety and biosecurity in this farming system and promote the implementation of ad hoc surveillance programs for influenza A viruses and other zoonotic pathogens at a global level.”

In response, Dutch virologist Marion Koopmans said humans are now “playing with fire”, while British doctor Jeremy Farrar added: “The greatest risk of a devastating flu pandemic is avian or animal flu that infects intermediate mammals, and evolves to mammal-to-mammal and human-to-human transmission with little or no human immunity.”

Highly pathogenic avian influenza virus from wild goshawks - Utsunomiya [NHK, 22 Feb 2023]

A wild goshawk found dead on the grounds of a house in Utsunomiya City on February 17 has been confirmed to be infected with a highly pathogenic avian influenza virus after detailed genetic testing was conducted.

On the 17th of this month, a wild goshawk was found dead on the grounds of a house in Utsunomiya City, and a simple test conducted by the prefectural government confirmed that it had tested positive for avian influenza.

A more detailed genetic test was conducted at a national research institute in Tsukuba City, Ibaraki Prefecture, and as a result, a highly virulent and highly pathogenic avian influenza virus was detected on March 22.

This is the fifth case of highly pathogenic avian influenza virus being detected in dead wild birds in the prefecture since last December.

The prefectural government is strengthening its surveillance to check for other dead wild birds within a 10-kilometer radius of where the goshawk was found, and is urging people to contact the prefectural government if they find a dead or weakened bird. (translated by M.Y.)

H5N1: Governments should invest in vaccines for all flu strains, says incoming WHO chief scientist [The BMJ, 22 Feb 2023]

By Elisabeth Mahase

Governments around the world should be investing in a H5N1 vaccine and running phase 1 and 2 trials to prepare for a potential outbreak among humans, outgoing Wellcome director Jeremy Farrar has said.

Farrar—who is leaving Wellcome after a decade to become the World Health Organization’s chief scientist later this year—said that in terms of potential pandemic events, H5N1 is a “big worry.”

Speaking at a Wellcome media briefing in which he shared his views on the barriers that science must overcome, Farrar warned that the current situation, whereby H5N1 influenza viruses are being allowed to spread among poultry, wild birds, and mammals, is the perfect way to “create something nasty.”

“If there was an outbreak of H5N1 in humans tomorrow, we wouldn’t be able to vaccinate the world in 2023,” Farrar said, when asked by The BMJ about the current outbreaks in animal populations. “My concern is that we’re in slow motion watching something—which may never happen, but if it were to happen—we would look back on and ask why we didn’t do more.”

Before his time at Wellcome, Farrar spent 18 years in Vietnam where he worked on understanding infectious diseases such as dengue, influenza, malaria, typhoid, and tuberculosis.

Interspecies transmission
While H5N1 viruses have been circulating among birds and poultry in various parts of the world for years, the latest outbreaks have sent warning signals to the scientific community, as the virus has been able to spread to places and species that were previously unreached.

This includes South America, where 10 countries have recorded their first ever cases. Both Argentina and Uruguay have declared national health emergencies after outbreaks. In Peru around 55 000 wild birds have died in coastal nature preserves, as well as around 600 sea lions, while in the US 58 million commercial poultry and backyard flocks have been affected.1
The virus has also reached mammals, invading a mink farm in Spain last October. In a report on the outbreak, researchers warned that mink “could serve as a potential mixing vessel for interspecies transmission among birds, mammals, and humans.”

So far, WHO has said it’s working with manufacturers to ensure that supplies of vaccines and antivirals would be available for global use if needed. It has also advised countries to “strengthen surveillance in settings where humans and farmed or wild animals interact.”

“Prepare for a 1918-like episode”
Farrar said it’s not just H5N1 that governments should be preparing for.

“What I would like to see, which I’m pushing for, is governments investing in vaccines for every single other strain of influenza that exists in the animal kingdom through at least phase 1 and 2 studies. So you know they’re safe, they’re immunogenic, and you know you could manufacture them,” he said.

On the size of the task, he said, “There’s not an unlimited number of influenza strains.” Farrar said it is key to have those vaccines in the bank, with a route to regulation and manufacturing in place. He added that even if H5N1 does not turn into a human pandemic situation this time, these investments would not be a loss.

“If at some point in the future we have a non-human influenza strain that causes a 1918-like episode, these vaccines would exist and you wouldn’t be starting from scratch. So it’s not as if it’s money that’s sunk and is not going to be of benefit,” Farrar said.

On top of investment in research, he has called on governments to improve their domestic security around farms and reduce the wildlife trade.

References
1. Mahase E. H5N1: Do we need to worry about the latest bird flu outbreaks?BMJ2023;380:401.doi:10.1136/bmj.p401 pmid:36801821

BMJ 2023;380:p434

Opinion | Is the United States Ready for Back-to-Back Pandemics? [The New York Times, 22 Feb 2023]

By David Wallace-Wells
Whatever happened to our Roaring Twenties? In the first year of the pandemic, it was common to hear predictions that however brutal and harrowing the near future seemed, the world would find itself, at some point, celebrating the end of Covid-19 — perhaps in a grand bacchanal to recall the dizzying decade that followed the Spanish flu of 1918 and 1919, which killed 675,000 Americans.
But that end never really came, not definitively. That the pandemic is no longer seen as an emergency is obvious; just look outside. But the country didn’t turn the page so much as limp forward, through a fog of exhaustion and loneliness and long Covid, into the dawn of a new period in which the coronavirus has retreated for most as an everyday threat but may well continue as gothic background noise, killing tens of thousands of Americans each year.

Bird Flu Continues: "Three Types of Viruses Invaded This Season" [NHK, 11 Feb 2023]

The National Institute of Agrobiological Sciences (NIAS), a national research institute located in Tsukuba City, Japan, has conducted a detailed investigation of the highly pathogenic avian influenza virus that has been spreading this season, and found that three types of the virus have entered the country.

The National Agricultural Research Institute (NRIRI) is calling for greater vigilance, as it is possible that the virus was brought in by migratory birds and spread over a wide area.

The National Agricultural Research Institute (NARI) conducted a detailed genetic study of 60 cases of highly pathogenic avian influenza that occurred at poultry farms and other facilities nationwide between late October last year and mid-January this year.

Of the 60 cases, 59 were H5N1 and one was H5N2, and as a result of genetic analysis, a total of three types of viruses were detected.

In addition to the two types of viruses identified in Japan last season, one type of virus identified in Western Siberia and Central China last season was newly detected.

This season, highly pathogenic avian influenza viruses have been confirmed in a wide range of areas in Japan, and the number of chickens and other birds destroyed in Ibaraki Prefecture has reached a record high of approximately 4.3 million.

The National Institute of Agrobiological Sciences (NIAS) has stated, "There is a possibility that the virus was brought to Japan by migratory birds and spread widely. We need to be even more vigilant about the possibility of the virus entering farms in the future." The organization is calling for thorough disinfection and inspection of bird nets and other measures to prevent the spread of the virus.

According to the National Agricultural Research Institute (NARI), genetic analysis of the viruses found in various locations revealed that two of the three highly pathogenic avian influenza viruses detected this season were also confirmed in Japan last season.

The first, called "20E," is a virus that is believed to have been spread by migratory birds from Europe to their breeding grounds in Siberia three summers ago, and entered Russia, Italy, Sweden, and other countries in autumn.

The second virus, called "21E," is believed to have been spread by migratory birds that were in Siberia in the summer before last and entered Japan in the fall.

Both viruses are believed to have migrated between Siberia and Europe, and between Siberia and Japan in both directions.

In addition, the virus called "21RC," which was confirmed in Japan for the first time this season, is presumed to have originated from migratory birds that moved from Western Siberia and China to Siberia in the summer of last year.

According to the National Institute of Agrobiological Sciences, the detection of viruses originating from Western Siberia and China has been increasing in Japan this season, and they have been confirmed in a wide range of areas in Japan.

(translated by M.Y.)

An avian flu outbreak is spreading to mammals. What is the risk to humans? [Medical Express, 21 Feb 2023]

by Ben Knight

The latest outbreak is not a cause for alarm in humans at this stage. Credit: Shutterstock.

Avian influenza—or bird flu, as it's commonly known—continues to run through bird populations, killing millions of animals worldwide. Now, a particularly infectious and lethal strain of the virus called H5N1 appears to be spreading to mammals, with cases reported in wild otters, foxes, seals and in farmed minks.

While transmission from an infected bird to another animal is not uncommon, it is unusual for the virus to spread between mammals, as is suspected with the H5N1 outbreak in minks. The virus not only appears to have passed from mink to mink, but in doing so, may have developed genetic mutations which could help it better infect other mammals.

Professor Bill Rawlinson, a virologist from the School of Biomedical Sciences, UNSW Medicine & Health, says the situation remains an issue with animal health but is not a cause for alarm in humans at this stage.

"The worry is a deadly H5N1 strain could mutate in a mammal like a mink and become more adaptable to people, but it doesn't appear we're on the cusp of that at the moment," Prof. Rawlinson says.

While we're still likely several steps away from a human-adapted version of the virus, there may be more chances that people will encounter it.

"The overall risk of contracting it is quite low, but the risk may be slightly higher for those who have close unprotected contact with infected birds and their saliva, mucous, and feces in industries like poultry," Prof. Rawlinson says.

A low, but anticipated threat
Since its emergence in the mid-1990s, scientists and health authorities have worried about the potential of H5N1 to evolve into a pandemic. Still, the threat remains low, and no human-to-human transmission has ever been recorded.

"Avian flu tends not to infect people because it simply can't bind as well in humans, so you're almost certainly not going to be infected by it walking around today in Australia," Prof. Rawlinson says.

However, in the rare instances H5N1 has jumped the species barrier and infected humans, it has been deadly. According to the World Health Organization, over half of the 868 cases of human infection with H5N1 since 2003 have been fatal.

Prof. Rawlinson says the current situation would be more worrying if there were signs the virus was spreading between mammals more genetically similar to humans, such as other primates.

"Pigs would be the other concern as they can be more easily infected with both human and avian flu strains, so may have potential to pass a super strain on to humans," Prof. Rawlinson says.

"Thankfully, that doesn't always seem to be the primary way avian infections cause human infections and hasn't been as much of an issue as we've feared to this point."

Monitoring the risks of animal viruses
Prof. Rawlinson says we should continue with routine preparedness measures in case the virus changes and becomes a more significant threat to human health. This includes strengthening a One Health System, with all health professionals, from doctors and vets to virologists and epidemiologists, working closely together to assess changing risks.

"We should continue sampling and testing wild birds and poultry, which is essential to be on top of any early signals if the situation is changing," Prof. Rawlinson says.

"If you do have regular contact with birds, and you observe sudden unexplained changes, it's essential to talk to a local vet or contact The Ministry of Health, so they can investigate.

"We also need to be on the lookout for people with unexpected, undiagnosed pneumonia-like infections."

Prof. Rawlinson also says it's also essential people get vaccinated for the flu every year, which may reduce the capacity for a person to host, and mix, avian and human strains.

"It's not so much about cross-protection with avian flu, although there may be a small amount.

But by vaccinating against human flu, we're less likely to see a mixing of avian and human flu strains.

"People have been very switched on to vaccination with COVID-19, and that needs to extend to the human flu, especially as we're likely to have another moderate to severe outbreak this year."

Ultimately, Prof. Rawlinson says the virus should warn us about the need to be wary of the increasing presence of zoonotic—animal-derived—diseases in our world.

"There are a range of zoonotic viruses, not just avian flu, that seem to be becoming part of a more regular cycle between animals and humans," Prof. Rawlinson says. "That doesn't mean they will always be a pandemic risk, but we should be continuing to monitor these events and be prepared to respond to any pandemic risk."

Avian flu strain shows transmissibility among mammals [PBS NewsHour, 21 Feb 2023]

By William Brangham & Courtney Norris

A highly contagious avian flu is infecting birds all over the globe. In the U.S., farmers have lost, or had to kill, over 58 million birds to try and prevent the spread of the virus. The H5N1 strain hasn’t caused any serious threat to humans, but outbreaks in some mammals raised concerns about the potential to spread further. Influenza researcher Scott Hensley joined William Brangham to discuss.

Amna Nawaz:
A highly contagious avian flu is infecting birds all over the globe.

Here in the U.S., farmers have lost or had to kill over 58 million birds to try and prevent the virus' spread. So far, this flu hasn't caused any serious threat to humans.

But as William Brangham reports, there are several new outbreaks that are raising some alarm.

William Brangham:
Thanks, Amna.

Over the last two years, the spread of this strain, known as H5N1, has been largely limited to birds. But now two particular outbreaks, one among farmed mink in Spain and another among wild sea lions in Peru, suggests that H5N1 might now be able to spread between mammals.

And that's raised concerns about the virus' potential to spread further and perhaps even make humans sick.

Scott Hensley is a professor of microbiology and an influenza researcher at the University of Pennsylvania.

Scott, thank you so much for being here.

Before we get to the mink and the sea lions, can you just remind us how bad H5N1 is among birds all over the world right now?

Scott Hensley, Penn Institute for Immunology: We have seen H5N1 circulate in birds before.

What makes this current situation unique is how widespread this particular clade of H5N1 virus is spreading. It's not a good time to be a bird today, because this virus has infected wild bird populations. And it's also infected domestic birds all across the world.

And, again, the unique thing about this particular virus is, it is getting into bird populations that we have not seen be infected historically with H5 viruses in the past.

William Brangham:
Yes, I was actually at an avian center in Minnesota several months ago, and we're seeing eagles and owls and raptors of all kinds getting this virus.

But, with regards to this — these cases of the sea lions and the mink, those seem to suggest that the virus is now spreading within mammals. Do you think that that evidence is — do you think that that's what's happening? And, if so, why is that a problem?

Scott Hensley:
Yes, so that's exactly what makes us a little bit nervous.

So, these viruses are obviously very good at attaching to avian cells and getting into bird cells and replicating. We know that because the virus is spreading again very rapidly among birds.

The good news is, is, the virus doesn't appear to be able to replicate in human cells very effectively.

But we have seen cases now, as you just outlined, the virus getting into mink, and there's likely mink-to-mink transmission that have occurred in the situation that we have seen in Spain. And we see the virus spreading to other mammals as well. This is alarming, because what we're afraid is that the virus might start changing. It might undergo acquiring different substitutions that enable better replication in these mammals.

And we're afraid that some of those same substitutions might enable the virus then to attach to human cells more effectively. Right now, again, the good news is, the virus appears to be very poor at infecting human cells. But we start to get nervous when we see these essential crossover events, when these avian viruses are getting into other animals.

William Brangham:
There have been, as I have mentioned briefly, some cases where the virus has jumped in, mostly when — I think of this one case in Colorado where a person was cleaning out a chicken farm that had suffered a big outbreak.

And so that wasn't a human-to-human transmission. It was just someone getting a big dose of this virus. What do we know about what this virus does to people if it does get into people?

Scott Hensley:
Well, there — luckily, there's been very limited number of infections with this particular H5N1 virus.

In the past, H5N1 viruses have been shown to have very high mortality rates. But, again, in this current outbreak, we have seen a limited number of human infections, mostly with folks who have had very close contact with birds. And there has not been many serious infections to date.

So, H5N1 certainly has the potential to cause a lot of disease and high mortality rates. This particular virus does not seem well-adapted at infecting humans. But this could change, of course, and something that we have to keep our eye on.

William Brangham:
So can you help put this into perspective for people?

Those people who might be seeing these reports and being alarmed about this idea of it jumping into humans, how worried should we be?

Scott Hensley:
Look, we don't have to be alarmed right now.

Look, don't run out to your pharmacy and buy 1,000 rolls of toilet paper.
(LAUGHTER)

Scott Hensley:
If you see a dead bird or a sick bird, certainly, stay away from it.

It's likely that this virus needs to acquire several substitutions before it can efficiently spread from human to human and start infecting humans. But we need to remain vigilant. The research community right now has to come together. We need to increase funding for surveillance to be able to track this virus in real time. And we have to understand better what changes this virus needs to have take place for it to jump into the human population.

So, an everyday person right now, again, avoid sick birds. I think, other than that, there's not a whole lot that you need to do. But this is the time for the research community to really come together and increase our surveillance efforts and start developing new vaccines in case this virus does jump into humans.

William Brangham:
All right, that is Scott Hensley at the University of Pennsylvania.

Thank you so much.

Scott Hensley:
OK. Thank you for having me.

Avian Influenza to Cause a Pandemic in Humans? Possibility of Adaptation to Mammals Shows "Tipping Point" Coming [WIRED.jp, 20 Feb 2023]

by Daisuke Takimoto

Avian influenza (H5N1) is spreading rapidly in the United States, Europe, and Japan. In what is said to be the worst outbreak in history, it is suspected that the virus may have adapted to mink, which are considered to be similar to humans as mammals, and that we have reached a tipping point in terms of the risk of causing a pandemic among humans.

The outbreak of highly pathogenic avian influenza (H5N1) in Argentina and Uruguay led to the declaration of national public health emergencies in both countries in mid-February 2023. It has been feared for decades that it could cause a pandemic in humans.

This latest outbreak brings to 10 the number of countries in South America where H5N1 has been confirmed for the first time. Peru, in particular, saw the deaths of more than 50,000 wild birds in the fall of 2010 and more than 600 sea lions in January 2011.

The fact that sea lions, which are mammals, were also infected, and the new revelation that H5N1 also occurred on a mink farm in Spain in October 2010, have forced public health officials to confront the possibility that H5N1, which is evolving unexpectedly, has adapted to pose a threat to other species as well. The public health community is being forced to confront the possibility that H5N1, which has evolved unexpectedly, may be adapting to become a threat to other species.

Emerging "Trends of Concern"
To be clear, H5N1 is not yet a threat to humans. While we have seen cases of avian flu outbreaks spreading to humans in the past few decades, there have been only two confirmed cases in the past 12 months. Specifically, there has only been one case of infection in an adult in Colorado in May 2010 and one in a 9-year-old girl in Ecuador in January (neither of which resulted in death).

And there is no evidence at this stage of the possible spread of the disease from newly confirmed mammals, such as sea lions and mink, to humans. However, the fact that the disease has spread from birds to mammals and then among mammals is a worrisome trend.

According to the International Veterinary Medical Bureau, outbreaks of H5N1 have recently been confirmed in at least 60 countries. H5N1" is the name given to two proteins on the surface of the virus.

Countries with recently confirmed outbreaks include the United States. In the United States, 43 million egg-laying chickens have died or been culled to prevent the spread of avian influenza in the past 22 years.

According to the USDA, this eliminated nearly one-third of the U.S. egg-laying chickens, resulting in a significant shortage of eggs. As a result, egg prices were 210% higher at the end of 2010 than at the end of 2009. The Department of Agriculture estimates that a total of nearly 58 million egg-laying chickens, chickens for egg-laying, and poultry raised by individual households died or were killed in 2010, and 500,000 were killed in 2011.

Increased Biosecurity Needed
The poultry industry is huge. In the U.S. alone, more than 9 billion chickens are raised for meat, 216 million for chickens, and 325 million for egg-laying. Chicken is the most consumed meat in the world.

Because of this scale, it is difficult to put the losses caused by avian influenza into a precise context. However, the current epidemic is the worst animal disease outbreak in U.S. history. It is also the worst recorded avian disease outbreak in the UK, Europe, and Japan. As for wild birds, they are difficult to monitor, but according to wildlife biologists, the damage to wild birds is also significant.

What can be done to protect wild birds may be almost nonexistent. Avian influenza is spread by migrating waterfowl during the season, but waterfowl can carry the virus without being harmed by infection.

For this reason, the poultry industry is attempting to prevent transmission by adopting procedures and poultry farm construction methods that are broadly referred to as "biosecurity." Biosecurity was introduced or enhanced following a devastating outbreak in 2003 that killed over 50 million birds.

As the H5N1 outbreak shows no signs of stopping, those who study the poultry industry are beginning to question whether it is possible to sufficiently increase biosecurity to prevent avian influenza, and if not, what other changes can be made to keep birds and humans safe? If not, what else can be changed to keep birds and humans safe?

Biosecurity can be effective, and we know it is. But it is a lot of work and may not be sustainable with the way poultry farms are built and the current workforce," said Carol Cardona, a veterinarian and professor of avian medicine at Veterinary Medicine University in Minnesota.

"The reason it could be valid is that companies that had outbreaks [of highly pathogenic avian influenza] in 2015 had fewer outbreaks in 22 years. That means they learned some lessons and took some measures. However, few companies were able to reduce outbreaks to zero."

Human Adaptation a Concern
The relentless spread of H5N1 is not only a concern in terms of its impact on poultry and wildlife, but also in terms of human transmission.

Avian influenza has long been considered the animal disease most likely to cause a global pandemic among humans. Even after the onslaught of the new coronaviruses, many scientists have not yet changed their minds.

The first case of H5N1 avian influenza transmitted from birds to humans was in 1997 in Hong Kong, where 18 people became ill and six died. Although a small number, the fatality rate was a shocking 33%.

Since then, human infections with various variants of H5N1 have been reported regularly. According to the World Health Organization (WHO), there have been 868 cases of human infection and 457 deaths through 2010. Based on these figures, the fatality rate is 52%.

However, the fact that the overall number is small still indicates that H5N1 has not adapted to humans to the extent that it can be easily transmitted from human to human and trigger a major outbreak.

Nevertheless, scientists are constantly monitoring H5N1 to see if a situation has arisen that would allow H5N1 to adapt to humans. For example, in January 2011, Spanish and Italian scientists revealed that in October 2010, a subspecies of H5N1 was confirmed to have infected a mink for fur on a mink farm in northwestern Spain.

H5N1 could have infected just one mink from a single wild bird or a dead chicken for food. Once it entered the farm, however, H5N1 adapted through minor mutations and was able to transmit from mink to mink. All of the farm's nearly 52,000 mink have been killed in an effort to contain this outbreak.

The outbreak was worrisome in two ways: H5N1 is beginning to adapt to mammals, and more importantly, to mink, a mammal directly related to humans.

Mink belong to the same family as ferrets, and when ferrets are infected with influenza, their symptoms progress in the same manner as humans. For this reason, they are so similar to humans that they are already being used in influenza research. The Challenge of High Density Breeding
There is one more concern about the mink outbreak. Although it has become so common in the livestock industry that almost no one is concerned about it, this Spanish farm is not the type of farm where mink are allowed to roam freely in large areas for fur. It was a farm where mink were raised in high-density cages.

Most of the poultry farms in the U.S. where bird flu outbreaks have occurred were also poultry farms that raised poultry in high-density confinement as well. The specific type of facility, however, depends on the type of poultry. Young chickens for poultry are housed in large metal sheds, egg-laying chickens are housed in sheds or, in some cases, indoor cages, and chickens for chickens are housed in sheds with mesh sides.

High-density confinement does not necessarily increase the risk of infection on a given farm, but once the virus is on the property, it can be transmitted to other animals. However, once the virus is on the property, high-density confinement ensures that a large number of individuals are exposed to the virus at any one time. In fact, some egg-laying poultry farms that were devastated by the avian influenza in 2010 lost 5 million birds.

Not only that, but infecting a large number of individuals also increases the risk of the virus mutating. For this reason, there are calls from outside the poultry industry that if huge poultry farms pose a risk of amplifying the virus, it may be necessary to take measures to reduce the size of the farms for defense purposes.

In the public debate about zoonotic diseases," says Dr. Baker, "it tends to quickly turn to vaccination, preparedness, and biosecurity. But no one discusses root cause control," says Jan Dutkiewicz, a political economist and visiting fellow at the Brooks McCormick Jr. Animal Law and Policy Clinic at Harvard Law School. If we were talking about preventing cancer caused by tobacco products, we would first talk about quitting smoking." But when we talk about the risk of zoonotic diseases, we rarely talk about reducing livestock production.

Reducing livestock production may seem an unthinkable proposition. In fact, it is estimated that 1.45 billion chicken wings were eaten in the United States during the Super Bowl on February 13 alone. And American culture doesn't question how the food on the plate is made.

The premise of industrial-scale animal agriculture is that consumers should not have to feel close to the reality of what goes on in the field and the violence against animals. You might even say that it wouldn't work without that premise," says Adam Scheingate, a professor of political science at Johns Hopkins University who studies food and agriculture policy. Most people really don't want to know how the food they eat is produced."

Still, Scheingate points out that outside the United States, when food-related disease risks are identified, action is taken quickly. For example, when bovine spongiform encephalopathy (BSE), also known as "mad cow disease," infected humans in the mid-1990s, killing 178 people with variant Creutzfeldt-Jakob disease, cattle farming practices were changed in the UK.

It's not about quitting poultry farming," says Andrew DiCoriolis, executive director of Farm Forward, a nonprofit organization dedicated to improving the welfare of livestock. "It's about understanding what factors are putting us most at risk and, in some cases, creating laws to eliminate those factors. For example, moving poultry farms off migratory bird routes, reducing the number of sheds that can be located in a particular area, reducing the density of individuals in sheds."

The Importance of a Reality-Accepted Approach
While the current avian influenza outbreak is frightening, it can also be seen as an opportunity to begin collecting big data on why poultry farming is so vulnerable to avian influenza. With avian influenza spreading to such a large scale, analyzing the data may reveal patterns that were previously unknown.

For example, is a particular feeding or watering system being used at the poultry farm where the outbreak occurred? Are chicks of a particular strain being purchased? Are they located in a particular geographical area? Are they on a specific migratory bird route?

There are not many studies that offer a complete set of best practices," he said. There's not a lot of research that gives us a complete version of best practices, because there's so much chance with viruses that we don't know exactly when they enter," said Megan Davis, a veterinarian, epidemiologist, and associate professor at Johns Hopkins University's Bloomberg School of Public Health.

In the wake of the avian flu outbreak of 2003, which was the worst outbreak the poultry industry had ever imagined, the industry sought to focus on the dangers posed to poultry farms by human traffic. To prevent visitors from unknowingly carrying the virus, companies took steps to address the risk of people working on separate properties living in the same house, trucking from infected poultry farms to uninfected ones, and bringing potentially contaminated mail and smart phones into the poultry industry. The H5N1 avian influenza virus is a major cause of death in the United States.

Now that the H5N1 avian influenza has infected wild birds so extensively, producers may also have to consider the risk of carrying the virus from the surrounding environment itself. If there are wetlands, ducks will come. A wooded area provides a habitat for raptors that target rodents that feed on fallen ears of grain. There is no such thing as perfect biosecurity, and it is impossible to completely separate the production system from the rest of the world. We need an approach that accepts this reality.

(translated by M.Y.)

As Bird Flu Spreads Across Globe, Can it Cause the 'Next Pandemic'? Explained [News18, 17 Feb 2023]

Explained: Avian flu virus has migrated from Europe and Asia to North America, where it has quickly expanded. Amid a human case in Ecuador, News18 answers - should we worry?

Nearly 15 million birds have been culled in Japan, a record high for a single season, amid an unprecedented spread of bird flu across the country, the farm ministry said Thursday. Japan’s Ministry of Agriculture, Forestry and Fisheries said the number of culled birds now stands at 14.78 million, about 50 per cent more than the record 9.87 million logged during the 2020-2021 season, Xinhua News Agency reported.

Meanwhile, the avian flu virus has migrated from Europe and Asia to North America, where it has quickly expanded to bird populations in South and Central America, said a report by Al Jazeera.

The report said the flu is no longer limited to birds. The list of wild mammals killed or culled in the United States 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 others.