Bird Flu is coming
- Thread starter SquatchinPoke
- Start date
Been doing that for ages and very well documented. Lots of info on that if you are interested. Poultry, swine, human proximity and cohabitation has been a driver for a very long time.
yea the poultry industry hasn't had an issue. If all our food dies do virus's matter?
so mammals have been passing to each other or like in the past mammals get it from eating an infected bird?
Not eating, necessarily (Influenza is not considered foodborne), but yes, they have been mixing them together, along with humans for a very long time.
Birds (poultry, mostly) have their H (hemaglutanin)(16 types) and N (neuraminidase)(9 types) types, and swine have their H and N types. One cell can be infected with multiple influenzas. Since the genetics are broken up into 8 fragments, the influenzas can mix and match. Sometimes the mix can be highly virulent, sometimes less virulent, sometimes not virulent at all.
For example, if an H1N1 (so called "swine flu" and pandemic flu) virus mixes in a cell with an H2N7 (a low pathogenic flu), you can get: H1N1, H1N7, H2N7, H2N1 influenzas out of it. Not all H1N1 (or in veterinary medicine, H3N8: dog version and horse version) behave the same, especially if mixed with other species.
Asian countries, in general (not just China), tend to be the hotbed since humans, poultry, and swine all live in very close proximity due to farming behaviors. Nothing new or nefarious in that.
If you want more information, there is a lot available on influenza and others due to change in cultural habits. One of the most fascinating for me is Nipah Virus in Malaysia. This would have been in 1999. Again, not nefarious, but a "subtle" change leading to the right environment for the virus to reach human populations.
You bet. I have no issues with the conspiracy theories on COVID. A lot of smart people dropped the ball on communication and other aspects to create the issues. People that have not studied or spent much time thinking about many of these pathogens have no idea how common many of these other infectious diseases pop up. Sometimes they are defeated with interventions, sometimes they "burn themselves out," sometimes it takes a combination. Much of this has gone on for well over 100 years.
Gotcha. Generally, small flocks/backyard flocks are not at the highest risk for it. Large operations are another story, but even then, this has been a topic since at least 2005 or so. I am taking a wait and see approach.
I will say I think we hit we hit the mark on the chicken industry and you will see a major event in the industry
There may be. It has been on high-alert since 2004-2005 or so. The big poultry people are certainly concerned. Biosecurity efforts are going to be important. Generally, biosecurity has involved human traffic in and out, and preventing animals from getting out. Better efforts have been made over the past few years to reduce outside animal exposures, at least in the poultry industry. Some of the methods, I am cool with, some not so much, but can accept the end goal is to prevent mass depopulation. USDA has done a pretty good job of keeping everybody informed on avian influenza. You are probably aware of this, but here is a link to updates and good info: https://www.aphis.usda.gov/aphis/ou...e-information/avian/avian-influenza/2022-hpai
Vito, some more information and if you want to see what has been knocking on our doors for a long time, I suggest you spend time looking back through promed/pubmed just to see the extent that this is not "new" but what has been going on for some time. Here is a link and you can look back several years: https://promedmail.org/
Spoiler for length
[3] Human case, HPAI H5N1
Date: Wed 29 Mar 2023
Source: Ministry of Health (MINSAL), Chile [in Spanish, machine
trans., abridged, edited]
https://www.minsal.cl/minsal-informa-primer-caso-humano-de-gripe-aviar-en-chile/
The Ministry of Health reports the 1st case of bird flu in humans in
Chile, reported in northern Chile. The sick person corresponds to a
53-year-old man affected by a severe influenza case. The patient is
stable within his gravity.
The health protocols established for the management of this disease
were activated, and the corresponding tests were taken for analysis by
the Institute of Public Health (ISP), which confirmed that it is avian
influenza.
The source of contact is investigated and whether there is a history
of others affected in the patient's environment.
The H5N1 virus or "bird flu" is a virus that can be transmitted from
birds or marine mammals to humans, but there are no known cases of
human-to-human transmission.
The Ministry of Health calls on citizens not to handle sick or dead
birds or mammals and urges poultry workers to follow the corresponding
safety protocols and to get vaccinated against seasonal influenza.
--
Communicated by:
ProMED
[To date [Wed 29 Mar 2023], Chile has reported HPAI in poultry,
backyard premises, wild bird, and mammals.
On 10 Mar 2023, HPAI H5N1 was detected in a commercial farm in
Rancagua, Libertador General Bernardo O'Higgins region. The latest
follow-up report sent to the WOAH on 27 Mar 2023 mentioned that
"cleaning and disinfection were completed after all poultry were
culled. The first actions for clinical surveillance and sampling for
laboratory tests were completed in 100% of the backyard and commercial
premises in the outbreak (3 km / [1.9 mi]) and surveillance (7 km /
[4.3 mi]) zones. The serology results for the culled birds were all
negative to the agar gel immunodiffusion test (60 sera). There are no
new outbreaks linked to this event." See report at
https://wahis.woah.org/#/in-review/4966.
In wild birds and in backyard premises, 69 outbreaks of HPAI subtype
H5N1 have been reported. See follow-up report No. 6, on 13 Mar 2023,
at https://wahis.woah.org/#/in-review/4775.
Chile has also reported HPAI H5N1 in sea lions (21 cases) and marine
otters (2 cases). See follow-up report No. 4, on 27 Mar 2023, at
https://wahis.woah.org/#/in-review/4922.
Detailed information and updates on avian influenza in Chile can be
found at https://www.sag.gob.cl/ia (in Spanish).
"With severe mortality rates, avian influenza can heavily impact the
health of both poultry and wild birds. Often considered mainly as
vectors of the disease, wild birds, including endangered species, are
also victims. The consequences of AI on wildlife could potentially
lead to a devastating effect on the biodiversity of our ecosystems.
"In addition, avian influenza can also cross the species barrier and
infect mammals, such as rats, mice, weasels, ferrets, pigs, cats,
tigers, dogs, and horses.
"The transmission of avian influenza from birds to humans is usually
sporadic and happens in a specific context. People who are in close
and repeated contact with infected birds or heavily contaminated
environments are at risk for acquiring avian influenza." Source: WOAH
Avian Influenza Portal
https://www.woah.org/en/disease/avian-influenza/.- Mod CRD
ProMED map:
Chile: https://promedmail.org/promed-post?place=8709226,7]
Date: Wed 29 Mar 2023
Source: Ministry of Health (MINSAL), Chile [in Spanish, machine
trans., abridged, edited]
https://www.minsal.cl/minsal-informa-primer-caso-humano-de-gripe-aviar-en-chile/
The Ministry of Health reports the 1st case of bird flu in humans in
Chile, reported in northern Chile. The sick person corresponds to a
53-year-old man affected by a severe influenza case. The patient is
stable within his gravity.
The health protocols established for the management of this disease
were activated, and the corresponding tests were taken for analysis by
the Institute of Public Health (ISP), which confirmed that it is avian
influenza.
The source of contact is investigated and whether there is a history
of others affected in the patient's environment.
The H5N1 virus or "bird flu" is a virus that can be transmitted from
birds or marine mammals to humans, but there are no known cases of
human-to-human transmission.
The Ministry of Health calls on citizens not to handle sick or dead
birds or mammals and urges poultry workers to follow the corresponding
safety protocols and to get vaccinated against seasonal influenza.
--
Communicated by:
ProMED
[To date [Wed 29 Mar 2023], Chile has reported HPAI in poultry,
backyard premises, wild bird, and mammals.
On 10 Mar 2023, HPAI H5N1 was detected in a commercial farm in
Rancagua, Libertador General Bernardo O'Higgins region. The latest
follow-up report sent to the WOAH on 27 Mar 2023 mentioned that
"cleaning and disinfection were completed after all poultry were
culled. The first actions for clinical surveillance and sampling for
laboratory tests were completed in 100% of the backyard and commercial
premises in the outbreak (3 km / [1.9 mi]) and surveillance (7 km /
[4.3 mi]) zones. The serology results for the culled birds were all
negative to the agar gel immunodiffusion test (60 sera). There are no
new outbreaks linked to this event." See report at
https://wahis.woah.org/#/in-review/4966.
In wild birds and in backyard premises, 69 outbreaks of HPAI subtype
H5N1 have been reported. See follow-up report No. 6, on 13 Mar 2023,
at https://wahis.woah.org/#/in-review/4775.
Chile has also reported HPAI H5N1 in sea lions (21 cases) and marine
otters (2 cases). See follow-up report No. 4, on 27 Mar 2023, at
https://wahis.woah.org/#/in-review/4922.
Detailed information and updates on avian influenza in Chile can be
found at https://www.sag.gob.cl/ia (in Spanish).
"With severe mortality rates, avian influenza can heavily impact the
health of both poultry and wild birds. Often considered mainly as
vectors of the disease, wild birds, including endangered species, are
also victims. The consequences of AI on wildlife could potentially
lead to a devastating effect on the biodiversity of our ecosystems.
"In addition, avian influenza can also cross the species barrier and
infect mammals, such as rats, mice, weasels, ferrets, pigs, cats,
tigers, dogs, and horses.
"The transmission of avian influenza from birds to humans is usually
sporadic and happens in a specific context. People who are in close
and repeated contact with infected birds or heavily contaminated
environments are at risk for acquiring avian influenza." Source: WOAH
Avian Influenza Portal
https://www.woah.org/en/disease/avian-influenza/.- Mod CRD
ProMED map:
Chile: https://promedmail.org/promed-post?place=8709226,7]
Last edited:
and another:
INFLUENZA (04): USA, INFLUENZA D, HUMAN, FIRST REPORT
In 2011, a farmer in Oklahoma had a bunch of sick pigs. The animals
had what looked like the flu.
"Just like a person with respiratory disease, the pigs had labored
breathing, maybe a runny nose, cough, and potentially a fever," says
virologist Benjamin Hause.
At the time, Hause was working at the company Newport Laboratories,
which develops custom vaccines for livestock. "We would detect and
isolate pathogens from animals. Then we would grow the pathogens in
the lab, kill them, and formulate vaccines," says Hause, who's now an
executive at Cambridge Technologies, another vaccine company.
The Oklahoma farmer took a few samples from the pigs' noses -- a bit
like how you swab your nose for an at-home COVID test. He sent the
samples to Hause so he could figure out what was making the pigs
sick.
Hause immediately thought that the regular flu virus was infecting the
pigs. "We expected to find influenza A," he says, "because that's the
most common problem." It's also the same type of virus that often
causes the seasonal flu in people.
But when he and his colleagues grew the virus in the lab, they quickly
realized they were wrong. Hause was shocked by what he saw.
"I thought, 'What is this thing? We've never seen anything like this
before,'" he says. "Right away, we were concerned that this virus
could infect people."
For decades, scientists thought that animal viruses seldom jump into
people. They thought these spillovers were extremely rare. But in the
past few years, studies have been showing that this thinking is
wrong.
"I don't think [spillover] is extremely rare," says evolutionary
virologist Stephen Goldstein at the University of Utah. "I mean, we
know this because when people start looking, people find it."
In fact, there's likely a whole group of animal viruses making people
sick all over the world that doctors know nothing about. They've been
hidden. They masquerade as a regular cold, flu, or even pneumonia.
For example, if you have a respiratory infection in the US, doctors
can identify the pathogen causing the infection only about 40% of the
time. There's growing evidence that the other 60% of infections could
be caused by animal viruses such as a dog coronavirus found in
Malaysia, Haiti, and Arkansas, or even possibly the same virus Hause
and his colleagues found in those pigs. Recent studies have made clear
that this virus floats in the air at farms and is likely infecting
people who work there.
Hause and his colleagues eventually figured out that they had stumbled
upon an entirely new influenza virus, unrelated to the ones known to
infect people. "It's completely different than influenza A," says
virologist Feng Li at the University of Kentucky, who co-led the
discovery of the new virus.
Once scientists started looking for signs of infections in other
animals, besides pigs, they found it nearly everywhere they looked: in
sheep, goats, camels, horses.
But Li says they hit the jackpot when they looked in one particular
animal: cows.
"The percentage of cows in the US that have antibodies to influenza D
is way, way high," he says. "Whenever you look at herds, about 50% of
individual cows have high levels of antibodies to this virus. That was
really surprising."
And it's not just cows in Oklahoma but across the whole country, from
west to east and north to south, Li says. "From California to Vermont,
and North Dakota to Texas, cows are infected with this virus. They are
the primary reservoir for the virus."
On top of that, this virus is incredibly stable, Li says. "It can
survive at high temperatures and in acidic environments," he says.
"That's why scientists have found influenza D in the air at airports
in the US." They've also found it in the air at chicken farms in
Malaysia.
And so the question has become: If this virus can infect so many
different animals and is found in so many cows, does it make people
sick? Especially the people who work closely with cows on dairy farms
or ranches?
In 2019 and 2020, scientists at Boston University ran a small and
simple experiment. They went to 5 dairy farms in the West and
Southwest, and they washed out the workers' noses before and after
their shifts working on the farms. Then they looked for influenza D
inside the washes.
The researchers studied only 31 workers over the course of only 5
days. But they found quite a lot of the virus. "We found about
two-thirds of the participants were exposed to influenza D at some
point during our study period," says environmental epidemiologist
Jessica Leibler, who led the study. They published their findings in
November in the journal Zoonoses [see citation below].
While Leibler and colleagues tested only a small number of workers,
the high percentage who had the virus in their noses suggests that
influenza D is quite likely common on dairy farms in the Southwest. If
the virus was rare on the farms, then finding it at such high levels
by chance would be highly unlikely. "To me, the findings suggest that
if you look for influenza D, you probably will find it," she says.
Now Leibler and her team looked only for an exposure to influenza D.
But previous studies have looked for signs of infections in cattle
workers in Florida. Specifically, the study tested for influenza D
antibodies in the workers' blood.
"They found a really, really high percentage of workers with influenza
D antibodies," Leibler says. "Again, it was again a small study, but
more than 90% of the workers had antibodies to influenza D, which
implies these workers weren't only exposed, but they were also
infected."
In contrast, the prevalence of influenza D antibodies in people who
don't work on farms was much lower. Only about 18% of the general
population showed signs of being infected, researchers reported in the
Journal of Clinical Virology [see 2nd citation below].
Now, no one knows yet if influenza D causes any symptoms in people.
But altogether, these studies indicate influenza D is likely what's
called an emerging virus, Leibler says. It's jumping into people who
work with animals, such as dairy farmers, but it's not likely
spreading much beyond that.
"This doesn't seem to be something, right now, that the general public
is exposed to in a large way," she says. "But it's something that's a
concern for these front-line workers exposed on farms."
That's because there's a real risk that the virus could adapt to
people as more and more workers are infected, she says. "Influenza
viruses mutate rapidly and frequently. So, over time, influenza D can
evolve. It could increase its ability to infect humans and be more
easily transmitted among humans or it could become more virulent" and
start making people sicker.
For that reason, Leibler and her colleagues are calling for more
research on, and surveillance of, this new flu to ensure the safety of
the dairy workers but also to ensure that the virus doesn't surprise
the world as SARS-CoV-2 did.
In fact, Stephen Goldstein of the University of Utah says to stop the
next pandemic before it occurs, scientists and officials should focus
on these viruses that have already made the jump into people instead
of cataloging viruses in wild animals.
"Doing virus discovery in wild animals is interesting from a
scientific standpoint, but from the standpoint of predicting
pandemics, I think it's a ridiculous concept," he says. "Instead, we
need surveillance -- active surveillance -- in humans and also in
domestic animals."
Currently, at least one company -- Cambridge Technologies -- is
working on a vaccine against influenza D for animals. But in general,
very few farms are looking out for the virus in animals or workers,
Jessica Liebler says.
For comments on this topic, NPR reached out to the National
Cattlemen's Beef Association, the lobbying group for cattle ranchers.
A spokesperson referred us to the US Department of Agriculture. The
USDA, along with the Centers for Disease Control and Prevention, said
in emails that, at this point, there isn't any evidence that influenza
D is causing significant harm to livestock, so there aren't currently
any surveillance systems in place for livestock or workers.
As Liebler points out, officials and scientists had a similar view of
coronaviruses for a long time: that they weren't a major concern
because they only caused a cold.
"Sometimes an animal virus doesn't seem to make people very sick and
so scientists brush it away as not really important," Leibler says.
"That's what scientists thought about coronaviruses for a long time:
that they weren't a major concern because they only caused a cold.
"It only took a huge global pandemic to realize that viruses can
change really quickly, and you don't know when they're going to
change."
In 2011, a farmer in Oklahoma had a bunch of sick pigs. The animals
had what looked like the flu.
"Just like a person with respiratory disease, the pigs had labored
breathing, maybe a runny nose, cough, and potentially a fever," says
virologist Benjamin Hause.
At the time, Hause was working at the company Newport Laboratories,
which develops custom vaccines for livestock. "We would detect and
isolate pathogens from animals. Then we would grow the pathogens in
the lab, kill them, and formulate vaccines," says Hause, who's now an
executive at Cambridge Technologies, another vaccine company.
The Oklahoma farmer took a few samples from the pigs' noses -- a bit
like how you swab your nose for an at-home COVID test. He sent the
samples to Hause so he could figure out what was making the pigs
sick.
Hause immediately thought that the regular flu virus was infecting the
pigs. "We expected to find influenza A," he says, "because that's the
most common problem." It's also the same type of virus that often
causes the seasonal flu in people.
But when he and his colleagues grew the virus in the lab, they quickly
realized they were wrong. Hause was shocked by what he saw.
"I thought, 'What is this thing? We've never seen anything like this
before,'" he says. "Right away, we were concerned that this virus
could infect people."
For decades, scientists thought that animal viruses seldom jump into
people. They thought these spillovers were extremely rare. But in the
past few years, studies have been showing that this thinking is
wrong.
"I don't think [spillover] is extremely rare," says evolutionary
virologist Stephen Goldstein at the University of Utah. "I mean, we
know this because when people start looking, people find it."
In fact, there's likely a whole group of animal viruses making people
sick all over the world that doctors know nothing about. They've been
hidden. They masquerade as a regular cold, flu, or even pneumonia.
For example, if you have a respiratory infection in the US, doctors
can identify the pathogen causing the infection only about 40% of the
time. There's growing evidence that the other 60% of infections could
be caused by animal viruses such as a dog coronavirus found in
Malaysia, Haiti, and Arkansas, or even possibly the same virus Hause
and his colleagues found in those pigs. Recent studies have made clear
that this virus floats in the air at farms and is likely infecting
people who work there.
Hause and his colleagues eventually figured out that they had stumbled
upon an entirely new influenza virus, unrelated to the ones known to
infect people. "It's completely different than influenza A," says
virologist Feng Li at the University of Kentucky, who co-led the
discovery of the new virus.
Once scientists started looking for signs of infections in other
animals, besides pigs, they found it nearly everywhere they looked: in
sheep, goats, camels, horses.
But Li says they hit the jackpot when they looked in one particular
animal: cows.
"The percentage of cows in the US that have antibodies to influenza D
is way, way high," he says. "Whenever you look at herds, about 50% of
individual cows have high levels of antibodies to this virus. That was
really surprising."
And it's not just cows in Oklahoma but across the whole country, from
west to east and north to south, Li says. "From California to Vermont,
and North Dakota to Texas, cows are infected with this virus. They are
the primary reservoir for the virus."
On top of that, this virus is incredibly stable, Li says. "It can
survive at high temperatures and in acidic environments," he says.
"That's why scientists have found influenza D in the air at airports
in the US." They've also found it in the air at chicken farms in
Malaysia.
And so the question has become: If this virus can infect so many
different animals and is found in so many cows, does it make people
sick? Especially the people who work closely with cows on dairy farms
or ranches?
In 2019 and 2020, scientists at Boston University ran a small and
simple experiment. They went to 5 dairy farms in the West and
Southwest, and they washed out the workers' noses before and after
their shifts working on the farms. Then they looked for influenza D
inside the washes.
The researchers studied only 31 workers over the course of only 5
days. But they found quite a lot of the virus. "We found about
two-thirds of the participants were exposed to influenza D at some
point during our study period," says environmental epidemiologist
Jessica Leibler, who led the study. They published their findings in
November in the journal Zoonoses [see citation below].
While Leibler and colleagues tested only a small number of workers,
the high percentage who had the virus in their noses suggests that
influenza D is quite likely common on dairy farms in the Southwest. If
the virus was rare on the farms, then finding it at such high levels
by chance would be highly unlikely. "To me, the findings suggest that
if you look for influenza D, you probably will find it," she says.
Now Leibler and her team looked only for an exposure to influenza D.
But previous studies have looked for signs of infections in cattle
workers in Florida. Specifically, the study tested for influenza D
antibodies in the workers' blood.
"They found a really, really high percentage of workers with influenza
D antibodies," Leibler says. "Again, it was again a small study, but
more than 90% of the workers had antibodies to influenza D, which
implies these workers weren't only exposed, but they were also
infected."
In contrast, the prevalence of influenza D antibodies in people who
don't work on farms was much lower. Only about 18% of the general
population showed signs of being infected, researchers reported in the
Journal of Clinical Virology [see 2nd citation below].
Now, no one knows yet if influenza D causes any symptoms in people.
But altogether, these studies indicate influenza D is likely what's
called an emerging virus, Leibler says. It's jumping into people who
work with animals, such as dairy farmers, but it's not likely
spreading much beyond that.
"This doesn't seem to be something, right now, that the general public
is exposed to in a large way," she says. "But it's something that's a
concern for these front-line workers exposed on farms."
That's because there's a real risk that the virus could adapt to
people as more and more workers are infected, she says. "Influenza
viruses mutate rapidly and frequently. So, over time, influenza D can
evolve. It could increase its ability to infect humans and be more
easily transmitted among humans or it could become more virulent" and
start making people sicker.
For that reason, Leibler and her colleagues are calling for more
research on, and surveillance of, this new flu to ensure the safety of
the dairy workers but also to ensure that the virus doesn't surprise
the world as SARS-CoV-2 did.
In fact, Stephen Goldstein of the University of Utah says to stop the
next pandemic before it occurs, scientists and officials should focus
on these viruses that have already made the jump into people instead
of cataloging viruses in wild animals.
"Doing virus discovery in wild animals is interesting from a
scientific standpoint, but from the standpoint of predicting
pandemics, I think it's a ridiculous concept," he says. "Instead, we
need surveillance -- active surveillance -- in humans and also in
domestic animals."
Currently, at least one company -- Cambridge Technologies -- is
working on a vaccine against influenza D for animals. But in general,
very few farms are looking out for the virus in animals or workers,
Jessica Liebler says.
For comments on this topic, NPR reached out to the National
Cattlemen's Beef Association, the lobbying group for cattle ranchers.
A spokesperson referred us to the US Department of Agriculture. The
USDA, along with the Centers for Disease Control and Prevention, said
in emails that, at this point, there isn't any evidence that influenza
D is causing significant harm to livestock, so there aren't currently
any surveillance systems in place for livestock or workers.
As Liebler points out, officials and scientists had a similar view of
coronaviruses for a long time: that they weren't a major concern
because they only caused a cold.
"Sometimes an animal virus doesn't seem to make people very sick and
so scientists brush it away as not really important," Leibler says.
"That's what scientists thought about coronaviruses for a long time:
that they weren't a major concern because they only caused a cold.
"It only took a huge global pandemic to realize that viruses can
change really quickly, and you don't know when they're going to
change."
Last edited:
And an interesting zoo case in the UK. This one shows why I say it isn't "typically" foodborne. This one discusses to a very basic degree how the virus can change to adapt to different hosts.
Scientists are investigating the possibility that bird flu was
transmitted among a pack of bush dogs at a zoo in England. A total of
10 bush dogs at the unnamed zoo died in what is being described as an
isolated event last November [2022]. The H5N1 avian influenza virus
was detected in the dead animals through retrospective sampling, the
UK Health Security Agency (UKHSA) said.
While mammal-to-mammal transmission has not been confirmed in the
dogs, it is one line of investigation. There is a possibility that the
dogs caught the virus through infected birds fed to them by
zookeepers.
In its updated risk assessment for bird flu, the UKHSA said the UK is
currently at Level 3, meaning there is "limited mammalian
transmission." This is a change in wording from the last assessment,
when the alert level was described as "changes in the virus genome
that could lead to mammal-to-mammal transmission."
However, the UKHSA insisted the level of risk had not changed. A
spokesperson said: "The risk to human health has not changed. As
previously, there is low confidence evidence of limited transmission
in mammals, but there is no current evidence that this risk is
changing."
A previous assessment defined the risk as spillover infections in
mammals with non-sustained transmissions between mammals, and the
scale of risk had been changed to provide more granular detail, a
source said.
But scientists are on high alert for transmission between animals
after incidents of mass infections and deaths of mammals in areas
around the world, including farmed mink in Spain, seals in the Caspian
Sea and sea lions in Peru.
There have been 23 deaths of wild mammals in the UK since the current
outbreak of the highly infectious H5N1 virus began 18 months ago,
including 2 dolphins, mainly due to isolated cases of animals
scavenging on infected dead birds. The 10 bush dogs would take the
total of wild and captive mammals that have died to 33.
Government scientists insist there is no change to the risk to human
health, which is classed as very low. Scientists at the UKHSA and the
SPI-M group, which produced modelling of the COVID pandemic for the
government, have also revealed different scenarios for what would
happen in a human pandemic of bird flu.
While there is still no evidence of human-to-human transmission, the
UKHSA said it wanted to prepare for the emergence of novel influenza
viruses. The current risks assessment says the H5N1 virus can
"successfully infect mammals and humans with high levels of direct
exposure (for example, scavenger mammalian species, humans working
closely with birds)."
There have been only 7 cases of bird flu in humans since October 2021.
It adds: "Polymerase basic protein (PB2) mutations associated with
mammalian adaptation, including E627K, are seen in mammalian
infections. There is evidence of transmission in farmed mink and
possible, though unconfirmed, transmission in populations of seals and
sea lions."
Dr Meera Chand, Deputy Director at UKHSA, said: "The latest evidence
suggests that the avian influenza viruses we're seeing circulating in
birds do not currently spread easily to people. However, viruses
constantly evolve, and we remain vigilant for any evidence of changing
risk to the population. It is right that we prepare for the emergence
of novel influenza viruses, and we are working with partners to ensure
that we have the tools and capabilities in place for these and other
emerging infections."
transmitted among a pack of bush dogs at a zoo in England. A total of
10 bush dogs at the unnamed zoo died in what is being described as an
isolated event last November [2022]. The H5N1 avian influenza virus
was detected in the dead animals through retrospective sampling, the
UK Health Security Agency (UKHSA) said.
While mammal-to-mammal transmission has not been confirmed in the
dogs, it is one line of investigation. There is a possibility that the
dogs caught the virus through infected birds fed to them by
zookeepers.
In its updated risk assessment for bird flu, the UKHSA said the UK is
currently at Level 3, meaning there is "limited mammalian
transmission." This is a change in wording from the last assessment,
when the alert level was described as "changes in the virus genome
that could lead to mammal-to-mammal transmission."
However, the UKHSA insisted the level of risk had not changed. A
spokesperson said: "The risk to human health has not changed. As
previously, there is low confidence evidence of limited transmission
in mammals, but there is no current evidence that this risk is
changing."
A previous assessment defined the risk as spillover infections in
mammals with non-sustained transmissions between mammals, and the
scale of risk had been changed to provide more granular detail, a
source said.
But scientists are on high alert for transmission between animals
after incidents of mass infections and deaths of mammals in areas
around the world, including farmed mink in Spain, seals in the Caspian
Sea and sea lions in Peru.
There have been 23 deaths of wild mammals in the UK since the current
outbreak of the highly infectious H5N1 virus began 18 months ago,
including 2 dolphins, mainly due to isolated cases of animals
scavenging on infected dead birds. The 10 bush dogs would take the
total of wild and captive mammals that have died to 33.
Government scientists insist there is no change to the risk to human
health, which is classed as very low. Scientists at the UKHSA and the
SPI-M group, which produced modelling of the COVID pandemic for the
government, have also revealed different scenarios for what would
happen in a human pandemic of bird flu.
While there is still no evidence of human-to-human transmission, the
UKHSA said it wanted to prepare for the emergence of novel influenza
viruses. The current risks assessment says the H5N1 virus can
"successfully infect mammals and humans with high levels of direct
exposure (for example, scavenger mammalian species, humans working
closely with birds)."
There have been only 7 cases of bird flu in humans since October 2021.
It adds: "Polymerase basic protein (PB2) mutations associated with
mammalian adaptation, including E627K, are seen in mammalian
infections. There is evidence of transmission in farmed mink and
possible, though unconfirmed, transmission in populations of seals and
sea lions."
Dr Meera Chand, Deputy Director at UKHSA, said: "The latest evidence
suggests that the avian influenza viruses we're seeing circulating in
birds do not currently spread easily to people. However, viruses
constantly evolve, and we remain vigilant for any evidence of changing
risk to the population. It is right that we prepare for the emergence
of novel influenza viruses, and we are working with partners to ensure
that we have the tools and capabilities in place for these and other
emerging infections."
