UK - Avian influenza in mammals 2025

[Michael Coston]

UK Confirms HPAI H5N5 In 2 Grey Seals






#18,628

While most of our HPAI concerns center around the H5N1 subtype, we continue to watch other strains (H5N6, H5N5, H5N9, etc.) with considerable interest since history has shown how quickly an obscure subtype can take center stage (see EID Journal: Comparison of 2016–17 and Previous Epizootics of HPAI H5 In Europe).

In China, H5N6 continues to spill over into humans, killing roughly 50% of those hospitalized. In Europe, and in Canada, we are watching a milder H5N5 virus circulate in wild birds, and occasionally spill over into mammals.​

Both have some degree of pandemic potential, but neither has spread as efficiently as the current HPAI H5N1 threat.

Today, in a brief notice (see above), the UK has announced the detection of HPAI H5N5 in two grey seals, detected in Norfolk. Last November, they reported an outbreak in poultry of H5N5 in Yorkshirealong with > 2 dozen dead birds infected with H5N5 fromaround the kingdom (see map below).






While this latest report hasn't appeared on the WOAH WAHIS list, that organization has already published 11 reports on H5N5 in birds and mammals since the first of the year from 6 different countries (Norway, Canada, Iceland, Greenland, Germany & the UK).

A few recent blogs on this subtype include:

Virus Evolution: Recurring Incursions & Dissemination of Novel Eurasian-origin H5Nx Avian Influenza Viruses in Atlantic Canada
​

More Reports On HPAI H5N5 In Iceland

Icelandic Food and Veterinary Authority (MAST) : H5N5 Infection In Domestic Cat
​

We've seen reports of H5N5 in European birds going back to 2016, but it was first detected in dead raccoons on Prince Edward Island about 21 months ago (see CIDRAP Report). Since last May, we've seen increasing reports of its western expansion (see WAHIS: More Reports of HPAI H5N5 in Canada).


Last July, in Cell Reports: Multiple Transatlantic Incursions of HPAI clade 2.3.4.4b A(H5N5) Virus into North America and Spillover to Mammals, researchers reported finding the mammalian adaptive E627K mutation in a number of samples.

They wrote:

Thus, while A(H5N5) viruses are comparably uncommon, their high virulence and mortality potential demand global surveillance and further studies to untangle the molecular markers influencing virulence, transmission, adaptability, and host susceptibility.​

While H5N5 is likely to remain a minor player, it is not impossible that we could the threat shift to H5N1 to H5N5, or H5N6, or to some other n-type, in the months or years ahead. After all, 5 years ago H5N1 was in serious decline, while HPAI H5N8 reigned supreme.

The H5Nx virus has an large - and growing - array of diverse hosts to inhabit, and no lack of genetic diversity on which to draw. All reasons why we could always see additional shifts in the fluscape in the future.


https://afludiary.blogspot.com/2025/02/uk-confirms-hpai-h5n5-in-2-grey-seals.html​

 

[Pathfinder]

Bird flu (avian influenza): latest situation in England

Find out about the latest bird flu situation in England and guidance for bird keepers and the public.

From:
Department for Environment, Food & Rural Affairs and Animal and Plant Health Agency
Published
4 November 2022
Last updated
18 February 2025 — See all updates​
...
Latest situation
...

18 February 2025

Following the successful completion of disease control activities and surveillance within the zone around a premises near Easingwold, Hambleton, North Yorkshire (AIV 2025/06), the 3km protection zone has been revoked and the area that formed this zone becomes a surveillance zone.

Influenza of avian origin has been detected in a small number of grey seals on the North Norfolk Coast, and we are aware that avian influenza has also been detected in wild birds in the area.

Mammals which have had close contact with infected wild birds or contaminated environments can become infected with influenza of avian origin.

The numbers involved were not above the usual annual mortality level at this site and this finding is evidence of the effectiveness of the UK’s wildlife surveillance system. There is no evidence to suggest an increased risk to non-avian wildlife.

Find out how we monitor the risk of influenza of avian origin in wild mammals.

...
https://www.gov.uk/government/news/bird-flu-avian-influenza-latest-situation-in-england
​

 

[Michael Coston]

UK Defra: H5N1 Detected In Domestic Sheep with Mastitis

UK Defra: H5N1 Detected In Domestic Sheep with Mastitis

Yorkshire – Credit Wikipedia



#18,386

Just over a year ago, HPAI H5N1 was detected in goats in the United States (see Minnesota BOAH Statement On HPAI H5N1 Infected Goat Kids), which was followed a few days later (March 25th) by the first HPAI detection in dairy cattle (see USDA Statement on HPAI In Dairy Cattle in Texas & Kansas Herds).

As we discussed a year ago, in A Brief History Of Influenza A In Cattle/Ruminants, while cattle had been experimentally infected in 2008, there had been little previous evidence of natural infection of these species. Since then, however, an August 2024 Preprint did report finding evidence of H5 antibodies in goats and sheep in Pakistan,.​

Overnight Defra ( the UK's Department for Environment, Food, and Rural Affairs) release a brief statement on that country's first HPAI H5 detection in livestock; in one domestic sheep in Yorkshire on a premises where H5N1 had been detected in captive birds.

First the official statement, after which a lengthier press release.

Confirmed findings of influenza of avian origin in captive mammals​

Updated 24 March 2025​

Sheep, March 2025

One domestic sheep (Ovis aries) tested positive for influenza of avian origin (H5N1) in March 2025. The case was identified following routine surveillance of farmed livestock on a premises in Yorkshire where highly pathogenic avian influenza (H5N1) had been confirmed in other captive birds. The single animal was a ewe with signs of mastitis but no other clinical signs. The milk was positive by polymerase chain reaction (PCR) and the blood tested positive for H5 antibodies.

All affected birds and the infected ewe were humanely culled to mitigate the risk of further disease spread. Further official testing of the remaining flock of sheep were all negative for the presence of avian influenza virus.​

The full press release follows. I'll have a bit more after the break.

Influenza of avian origin confirmed in a sheep in Yorkshire

Influenza of avian origin (H5N1) has been confirmed in a single sheep in Yorkshire.

From: Department for Environment, Food & Rural Affairs and Animal and Plant Health Agency Published24 March 2025

The UK’s Chief Veterinary Officer has confirmed a case of influenza of avian origin (H5N1) in a single sheep in Yorkshire following repeat positive milk testing.

The case was identified following routine surveillance of co-located livestock on a premises where avian influenza had been confirmed in captive birds. Defra has introduced livestock surveillance on infected premises following the outbreak of avian influenza in dairy cows in the US.

The infected sheep has been humanely culled to enable extensive testing. Further testing in the remaining flock of sheep at the premises was undertaken by the avian influenza national reference laboratory at the Animal and Plant Health Agency Weybridge laboratory. No further infection with avian influenza virus was detected in the remaining flock and this remains a single case in a mammal detected on the premises.

While this is the first time this virus has been reported in a sheep, it is not the first time influenza of avian origin has been detected in livestock in other countries. There is no evidence to suggest an increased risk to the nation’s livestock population.

However, the UK Chief Veterinary Officer is urging all livestock keepers to remain vigilant to the clinical signs of avian influenza following recent outbreaks. All keepers must maintain good biosecurity which is essential to protect the health and welfare of their animals and critical to preventing the further spread of disease in the event of an outbreak.

In line with the UK’s international reporting requirements, this case will now be reported to both the World Organisation for Animal Health (WOAH) and the World Health Organisation.

UK Chief Veterinary Officer Christine Middlemiss said:

“We have confirmed the detection of influenza of avian origin (H5N1) in a single sheep on a farm in Yorkshire. Strict biosecurity measures have been implemented to prevent the further spread of disease.

“While the risk to livestock remains low, I urge all animal owners to ensure scrupulous cleanliness is in place and to report any signs of infection to the Animal Plant Health Agency immediately.”

The UK Health Security Agency (UKHSA) has said that avian influenza is primarily a disease of birds and the risk to the general public’s health is very low, but people should not touch any dead or sick wild birds they find.

The Food Standards Agency advises that properly cooked poultry and poultry products, including eggs, remain safe to eat and avian influenza poses a very low food safety risk to UK consumers since the H5N1 virus is not normally transmitted through food.

Dr Meera Chand, Emerging Infection Lead at the UK Health Security Agency, said:

“Globally, we continue to see that mammals can be infected with avian influenza A(H5N1).

“However, current evidence suggests that the avian influenza viruses we’re seeing circulating around the world do not spread easily to people – and the risk of avian flu to the general public remains very low.

“UKHSA will continue to monitor the situation closely alongside Defra, DHSC, Animal and Plant Health Agency and Food Standards Agency.

“UKHSA has established preparations in place for detections of human cases of avian flu and will respond rapidly with NHS and other partners if needed.”

Robin May, Chief Scientific Adviser at the FSA said:

“We are working very closely with Defra, UKHSA and Food Standards Scotland following the discovery of avian influenza virus in a sheep in the UK. Our advice remains that bird flu poses a very low food safety risk to UK consumers since the H5N1 virus is not normally transmitted through food.

“We continue to monitor the situation closely and will assess any emerging information to continue to ensure UK food is safe.”  

What you can do   

Avian influenza is notifiable in all poultry and other captive birds and Influenza of avian origin is notifiable in both kept and wild mammals. If you suspect your animals are infected with avian influenza virus you must report it to the APHA immediately by calling:

· 03000 200 301 in England   

· 0300 303 8268 in Wales   

· Contacting your local Field Services Office in Scotland

Failure to do so is an offence.

We have published a case definition for influenza of avian origin to support decisions around reporting suspicion, together with further information on how we  monitor the risk of influenza of avian origin in wild mammals gov.uk.​

At this point there is no word on the genotype, and nothing has been posted on the WOAH WAHIS dashboard.

While Germany's FLI published a report last summer on the successful Experimental Infection Of Dairy Cows With European H5N1 Virus - and urged increased vigilance - most countries outside of the United States have not adopted routine surveillance or testing of livestock for H5N1 because the B3.13 genotype has only been detected in the United States.​

Last October the UK released the following risk analysis. Since then, of course, we've seen cattle infected by the D1.1 genotype as well.

Research and analysis
HAIRS risk statement: Avian influenza A(H5N1) in livestock

Updated 24 October 2024

Risk statement

This risk statement provides a qualitative description of the zoonotic risk avian influenza (AI) A(H5N1) clade 2.3.4.4b genotype B3.13 would present to people in contact with animals in the UK, and highlights evidence gaps and recommendations for mitigating the risk of zoonotic transmission.

Although new detections have been reported in dairy cattle, cats, alpacas and humans in the USA, and additional information has become available since the last risk statement (published in May 2024), the HAIRS group determined that this remains at most a very low risk.This is because there is no evidence to suggest AI A(H5N1) clade 2.3.4.4b genotype B3.13 is present in the UK. The HAIRS group will continue to monitor the situation and update this risk statement if any substantial developments arise.​

Between today's announcement, the FLI's 2024 assessment that European genotypes could infect cattle, and the recent detection of genotype D1.1 in dairy cattle in Nevada and Arizona, we can probably expect some sort of update from the HAIRS group in the days or weeks ahead.


Stay tuned.


https://afludiary.blogspot.com/2025/03/uk-defra-h5n1-detected-in-domestic.html
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[Michael Coston]

UK APHA: More Detections (n=13) of HPAI H5N5 In Seals

UK APHA: More Detections (n=13) of HPAI H5N5 In Seals






#18,388

Five weeks ago the UK made a brief announcement on the detection of HPAI H5N5 In 2 Grey Seals in Norfolk. This was the first detection of HPAI H5 in a non-avian species in the UK in nearly 2 years, and the first such detection involving the H5N5 subtype.

HPAI H5N5 is a reassortant offshoot of the clade 2.3.4.4b H5N1 virus, which has turned up sporadically in European birds, cats in Iceland, birds in the the UK - and since 2023 in Canada - infecting both birds and mammals.​

Last November, the UK reported an outbreak in poultry of H5N5 in Yorkshire along with > 2 dozen dead birds infected with H5N5 from around the kingdom (see map below).



Last July, in Cell Reports: Multiple Transatlantic Incursions of HPAI clade 2.3.4.4b A(H5N5) Virus into North America and Spillover to Mammals, researchers reported finding the mammalian adaptive E627K mutation in a number of samples.
They wrote:

Thus, while A(H5N5) viruses are comparably uncommon, their high virulence and mortality potential demand global surveillance and further studies to untangle the molecular markers influencing virulence, transmission, adaptability, and host susceptibility.​

Over the weekend the UK's APHA announced the detection of an additional 13 grey seals with H5N5, and the disclosure that the mammalian E627K mutation was detected as well.

Note 1: findings in grey seals in North Norfolk

Following the initial detection of avian species (great black-backed gulls (Larus marinus)) and two grey seals (Halichoerus grypus) testing positive for high pathogenicity avian influenza virus (HPAIV) H5N5 at Blakeney point, Norfolk in February 2025, further sampling was undertaken by the avian influenza national reference laboratory in collaboration with APHA’s Diseases of Wildlife Scheme to establish the broader impact of the virus on seals and birds in that location.

A total of 40 seal carcasses were sampled from the site and from that 37.5% (n=15) tested positive for HPAIV H5N5.

These animals are part of a well-established pinniped colony in Norfolk. Mortality noted at this seal colony was below the expected baseline of 10% during pupping and sampling efforts in seals were triggered following the observation of a mortality event in gulls that also tested positive for HPAIV.

The sequence generating from positive seal samples included a mammalian adaptive mutation (E627K) in one gene (PB2) but this mutation has been observed in numerous positive samples from mammals detected previously both in Great Britain and globally, and in isolation isn’t considered to represent an increase in zoonotic risk.

It is likely the animals were exposed to the same source of infected wild birds.

We cannot determine with certainty whether influenza of avian origin was the sole cause of death in these wild animals, and it is possible other factors may have contributed. All findings are also reported to the World Organisation for Animal Health (WOAH).​

While H5N5 remains a minor player, it is not impossible that we could a shift from H5N1 to H5N5, or H5N6 (or to some other n-type), in the months or years ahead. After all, little more than 5 years ago H5N1 was in serious decline, while HPAI H5N8 was dominant.

The H5Nx virus has an large - and growing - array of diverse avian and mammalian hosts to inhabit, and no lack of genetic diversity on which to draw.​

While past performance is no guarantee of future results, its current trajectory is nevertheless concerning.

https://afludiary.blogspot.com/2025/03/uk-aphis-more-detections-n13-of-hpai.html
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[Pathfinder]

Bird flu (avian influenza): latest situation in England

Find out about the latest bird flu situation in England and guidance for bird keepers and the public.
From: Department for Environment, Food & Rural Affairs and Animal and Plant Health Agency
Published 4 November 2022 Last updated 24 March 2025 — See all updates
...
Latest situation
...
24 March 2025

Influenza of avian origin (H5N1) has been detected in a sheep in England. The case was identified following routine surveillance of farmed livestock on a premises in Yorkshire where highly pathogenic avian influenza (H5N1) had been confirmed in other captive birds. The ewe tested positive for H5 antibodies in the blood, and her milk was positive for H5 RNA by polymerase chain reaction (PCR). The ewe had been showing clinical signs of mastitis.

All affected birds and the infected ewe were humanely culled to mitigate the risk of further disease spread. Further official testing of the remaining flock of sheep at the premises, including the lambs of the affected ewe, were negative for the presence of avian influenza virus.

While this is the first time avian influenza virus has been detected in a sheep, it is not the first time influenza of avian origin has been detected in livestock in other countries. There is no evidence to suggest an increased risk to the nation’s livestock population.

The case definition for influenza of avian origin has been updated and provides further guidance on how and when to report suspicion in mammals.
...
21 March 2025

Further details of the investigation into the finding of influenza of avian origin in grey seals on the North Norfolk Coast have been published.

Mammals which have had close contact with infected wild birds or contaminated environments can become infected with influenza of avian origin. Find out how we monitor the risk of influenza of avian origin in wild mammals.

The numbers involved were not above the usual annual mortality level at this site and this finding is evidence of the effectiveness of the UK’s wildlife surveillance system. There is no evidence to suggest there is an increased risk to non-avian wildlife.
...

https://www.gov.uk/government/news/...-latest-situation-in-england#latest-situation

 

[Pathfinder]

Research and analysis

Confirmed findings of influenza of avian origin in non-avian wildlife

Updated 28 March 2025

Applies to England, Scotland and Wales

...

​

Note 1: findings in grey seals in North Norfolk

Following the initial detection of avian species (great black-backed gulls (Larus marinus)) and two grey seals (Halichoerus grypus) testing positive for high pathogenicity avian influenza virus (HPAIV) H5N5 at Blakeney point, Norfolk in February 2025, further sampling was undertaken by the avian influenza national reference laboratory in collaboration with APHA’s Diseases of Wildlife Scheme to establish the broader impact of the virus on seals and birds in that location.

A total of 40 seal carcasses were sampled from the site and from that 37.5% (n=15) tested positive for HPAIV H5N5.

These animals are part of a well-established pinniped colony in Norfolk. Mortality noted at this seal colony was below the expected baseline of 10% during pupping and sampling efforts in seals were triggered following the observation of a mortality event in gulls that also tested positive for HPAIV.

The sequence generating from positive seal samples included a mammalian adaptive mutation (E627K) in one gene (PB2) but this mutation has been observed in numerous positive samples from mammals detected previously both in Great Britain and globally, and in isolation isn’t considered to represent an increase in zoonotic risk.

It is likely the animals were exposed to the same source of infected wild birds.

We cannot determine with certainty whether influenza of avian origin was the sole cause of death in these wild animals, and it is possible other factors may have contributed. All findings are also reported to the World Organisation for Animal Health (WOAH).
​...

https://www.gov.uk/government/publi...fluenza-of-avian-origin-in-non-avian-wildlife

 

[Pathfinder]

​

Confirmed findings of avian influenza in non-avian wildlife in 2025

​

Note 1: findings in grey seals in North Norfolk

Following the initial detection of avian species (great black-backed gulls (Larus marinus)) and two grey seals (Halichoerus grypus) testing positive for high pathogenicity avian influenza virus (HPAIV) H5N5 at Blakeney point, Norfolk in February 2025, further sampling was undertaken by the avian influenza national reference laboratory in collaboration with APHA’s Diseases of Wildlife Scheme to establish the broader impact of the virus on seals and birds in that location.

A total of 40 seal carcasses were sampled from the site and from that 37.5% (n=15) tested positive for HPAIV H5N5.

These animals are part of a well-established pinniped colony in Norfolk. Mortality noted at this seal colony was below the expected baseline of 10% during pupping and sampling efforts in seals were triggered following the observation of a mortality event in gulls that also tested positive for HPAIV.

The sequence generating from positive seal samples included a mammalian adaptive mutation (E627K) in one gene (PB2) but this mutation has been observed in numerous positive samples from mammals detected previously both in Great Britain and globally, and in isolation isn’t considered to represent an increase in zoonotic risk.

It is likely the animals were exposed to the same source of infected wild birds.

We cannot determine with certainty whether influenza of avian origin was the sole cause of death in these wild animals, and it is possible other factors may have contributed. All findings are also reported to the World Organisation for Animal Health (WOAH).

Note 2: findings in a grey seal in Cornwall

Sampling of a dead 8-month-old grey seal reported in Cornwall confirmed the presence of influenza A of subtype H7N1. The potential source of infection is wild birds, although very few seal sequences are available and the diversity of influenza A viruses in seals is poorly understood as is the dynamic of virus exchange between seals and birds. The cleavage site sequence indicated a motif consistent with a low pathogenicity virus if this virus had been found in poultry. However, the relevance of that cleavage site for seals is less clear.

The sequence generated from this positive seal sample included a mammalian adaptive mutation (E627K) in one gene (PB2) but this mutation has been observed in numerous positive samples from mammals detected previously both in Great Britain and globally, and in isolation isn’t considered to represent an increase in zoonotic risk. We cannot determine with certainty whether influenza A was the sole cause of death, and it is possible other factors may have contributed.
​
...
https://www.gov.uk/government/publi...fluenza-of-avian-origin-in-non-avian-wildlife

 

[Michael Coston]

UK APHA: Detection of Avian H7N1 In Grey Seal



Credit UK APHA

#18,791

We've known for decades that marine mammals (seals, whales, sea lions, otters, etc.) are susceptible avian, and other types, of influenza viruses. The emergence and spread of HPAI H5Nx clade 2.3.4.4b around the globe has killed tens - perhaps hundreds - of thousands of pinnipeds over the past 2 years.

Preprint: Pathology of Influenza A (H5N1) Infection in Pinnipeds Reveals Novel Tissue Tropism and Vertical Transmission.​

Nature Reviews: The Threat of Avian Influenza H5N1 Looms Over Global Biodiversity​

But other avian viruses have been documented in marine mammals for decades. A few (of many) reports include:

• During the winter of 1979-1980 seals were found suffering from pneumonia on the Cape Cod. In that instance, the culprit turned out to be an H7N7 influenza. (see Isolation of an influenza A virus from seals G. Lang, A. Gagnon and J. R. Geraci)
• In November of 2011 a die off of seals in New England that was eventually tied to an H3N8 avian Flu Virus. 2012's mBio: A Mammalian Adapted H3N8 In Seals, presented evidence that this virus had recently adapted to better bind to alpha 2,6 receptor cells, the type found in the human upper respiratory tract.

• A large outbreak was reported from northern Europe (mostly Denmark and Germany & Sweden) in 2014, when as many as 3,000 harbor seals reportedly died from avian H10N7 (see Avian H10N7 Linked To Dead European Seals), prompting warnings to the public not to touch seals.
• In 2017, during the HPAI H5N8 epizootic in Europe, that emerging subtype (clade 2.3.4.4.B) was found in Grey seals in the Baltic Sea (see EID Journal: Highly Pathogenic Avian Influenza A(H5N8) Virus in Gray Seals, Baltic Sea).

Earlier this year the UK reported (two) outbreaks of clade 2.3.4.4b HPAI H5N5 in Grey seals (see here, and here). They reported finding the mammalian adaptive mutation PB2-E627K mutation in some of these isolates.

This amino acid substitution has been seen in other mammalian spillovers (see Cell Reports: Multiple Transatlantic Incursions of HPAI clade 2.3.4.4b A(H5N5) Virus into North America and Spillover to Mammals).​

This week the UK's APHA/Defra is reporting the detection of a low-path avian H7N1 virus in a grey seal pup, which was found dead near Cornwall. While H7 viruses have been (rarely) reported in pinnipeds, this (AFAIK) appears to be the first confirmed H7N1 virus.

First the brief report, after which I'll have a bit more on H7 viruses.

Note 2: findings in a grey seal in Cornwall

Sampling of a dead 8-month-old grey seal reported in Cornwall confirmed the presence of influenza A of subtype H7N1. The potential source of infection is wild birds, although very few seal sequences are available and the diversity of influenza A viruses in seals is poorly understood as is the dynamic of virus exchange between seals and birds. The cleavage site sequence indicated a motif consistent with a low pathogenicity virus if this virus had been found in poultry. However, the relevance of that cleavage site for seals is less clear.

The sequence generated from this positive seal sample included a mammalian adaptive mutation (E627K) in one gene (PB2) but this mutation has been observed in numerous positive samples from mammals detected previously both in Great Britain and globally, and in isolation isn’t considered to represent an increase in zoonotic risk. We cannot determine with certainty whether influenza A was the sole cause of death, and it is possible other factors may have contributed.​

While H5 avian viruses have captured most of our attention over the past 25 years, for 5 years during the last decade China's H7N9 epidemic showed us that H7 viruses has genuine pandemic potential, producing > 1600 infections in China.
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[TD]H7N9 Epidemic Waves - June 14th 2017 - Credit FAO[/TD]
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Other human spillovers include:

• In December of 2016, at least two veterinarians caring for sick cats at a NYC shelter were mildly infected with H7N2 (seeJ Infect Dis: Serological Evidence Of H7N2 Infection Among Animal Shelter Workers, NYC 2016).

• 3 mild cases were reported in Italy in 2013 (see ECDC Update & Assessment: Human Infection By Avian H7N7 In Italy).

• Mexico reported a couple of mild human H7N3 infections back in 2012 (see MMWR: Mild H7N3 Infections In Two Poultry Workers - Jalisco, Mexico), resulting in conjunctivitis without fever or respiratory symptoms.

• Twenty-two years ago (2003) world's attentions were focused on a different avian flu virus - HPAI H7N7 - which spread rapidly across hundreds of poultry farms in the Netherlands, infecting scores of farmers, and which killed a local veterinarian (see Human-to-human transmission of avian influenza A/H7N7, The Netherlands, 2003).

A follow up investigation of the 2003 outbreak by the RIVM found the spread of the virus to be far greater than originally reported, suggesting as many as 1,000 human infections occurred.

So, while H7 viruses are generally thought of as being less dangerous than H5 viruses - and primarily an agricultural concern - that reputation is not entirely warranted.​

That said, the detection of H7N1 in a single seal pup in the UK is mostly likely a one-off, or incidental finding. Obviously, if more turn up, it will warrant additional scrutiny.

But this is another reminder that much of what happens with viral evolution goes on outside of our view. While we focus on our current HPAI H5 threat, we could easily be blindsided by something brewing unseen out in left field.​

Which is why we need to treat pandemic preparedness as integral to our national security, not as something we hastily ramp up whenever a new threat appears.


https://afludiary.blogspot.com/2025/07/uk-apha-detection-of-avian-h7n1-in-grey.html
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