Discussion thread: H5N1 avian flu in US dairy cows including human cases (poultry, dairy workers) - March 24, 2024 +

[sharon sanders]

FluTrackers.com
@FluTrackers
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3h
Remember this post? Well...


Quote

FluTrackers.com
@FluTrackers
·
Dec 15, 2023
There is so much H5N1 avian flu spreading globally in birds right now that we are having a hard time keeping up with the OIE reports.

Pay attention to your agricultural officials & employ personal protection methods as a precaution.

h/t Pathfinder, Shiloh, Lance, @Fla_Medic


2.9K
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[Pathfinder]

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https://www.aphis.usda.gov/livestoc...an/avian-influenza/hpai-detections/wild-birds

 

[sharon sanders]

This site is not going to use any other name for H5N1 avian flu - even if the strain appears in a non-avian animal, like a cow, for instance.

 

[Pathfinder]

WHAT'S HAPPENING WITH DAIRY COWS AND BIRD FLU?
...
By Bloomberg School of Public Health staff report / Published 2 hours ago

In this Q&A, adapted from the April 8 episode of Public Health On Call, Stephanie Desmon speaks with Meghan Davis, associate professor in the Department of Environmental Health and Engineering, and Andrew Pekosz, professor in the Department of Molecular Microbiology and Immunology, about H5N1's jump between species, what that means for the virus's pandemic potential, and what the appearance of the virus in dairy means for consumers.
...
Can we expect to see more cases in humans?

Pekosz: I expect that over the next few weeks,we're going to be seeing more cases in cows and humans, because humans are in close contact with cows during many dairy processes. Hopefully, this will not be a large outbreak, but we certainly expect to see more cases.
...
Were you surprised by this H5N1 outbreak?
'
Davis: I am surprised that it's in dairy cows, because when we think about animal models for influenza, we think about mustelids, like ferrets or mink. We have also seen a number of sick farm cats that tested positive. What is most interesting about seeing [H5N1] in dairy is that researchers haven't been focusing on biosecurity and biocontainment for things like avian influenza—which is typically transmitted from a bird reservoir. Dairy farms are often quite open to the air—birds might spend time in areas where the cows eat, for example.

One of the other things we are seeing is some symptoms of disease in the cows. I've not heard of high mortality yet, but they have been showing fairly nonspecific signs, like not eating or milking well. Most of these tend to be somewhat older cows because adult cows who are lactating are in a different category of susceptibility than young calves. What we don't know yet is if perhaps the virus is in all the populations within the farm, and only some of them are showing symptoms.
...
What can the surveillance data from infected cows tell us?

Pekosz: Two things are really important. One is: The virus has gone from the respiratory tract through lots of different organs, through the blood, and made it all the way to the milk. In humans, the influenza virus stays within the respiratory tract. We have seen H5N1 move out of the respiratory tract in other animals, but usually that's associated with a really fast mortality. As soon as the virus leaves the lungs, the animals are so sick that they die. We're seeing a case here where the animals don't seem to be really sick, but the virus is making it to other parts of the animal. That's going to tell us something perhaps unique about the H5N1 virus compared to seasonal human viruses.

The second critical thing is: If there is spread of this virus from cow to cow, is the virus changing and getting better adapted to replicating or spreading in cows? Bird flu jumping to mammals is important because anything that allows the virus to adapt to a mammal has the potential for making it better able to infect humans. Understanding what happens now with the spread of the virus and how the sequence of the virus changes is going to be critically important. The first sequences [from cows] look like the virus is almost identical to the bird virus. But we haven't really sampled animals that presumably acquired the infection from other cows.
...
Davis: ...
Something I'm very interested in is: Where were each of these cows exposed? To what degree was this one event that is now spreading through these networks of sale and trade and movement of dairy cows? Or is this multiple events in which you've had an introduction [of the virus] from birds? Because that also changes the dynamics as we think about genetics and the potential for evolution.
...

https://hub.jhu.edu/2024/04/15/qa-avian-flu-in-cows/

 

[sharon sanders]

This site is not going to use any other name for H5N1 avian flu - even if the strain appears in a non-avian animal, like a cow, for instance.

A great explainer on this issue by @thijskuiken :

(my bolding in item #19)

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Thijs Kuiken
@thijskuiken
1/n Changing the name of highly pathogenic avian influenza virus H5N1 into ‘bovine influenza A virus’ implies it has become endemic in cattle, a worst-case scenario! But how are influenza viruses actually classified? A thread: #vogelgriep

bovinevetonline.com
AABP Decides to Reference Cattle Disease as Bovine Influenza A Virus (BIAV)
11:29 AM · Apr 16, 2024
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Thijs Kuiken
@thijskuiken
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2/n When we write ‘bird flu virus’ or ‘avian influenza virus’ in the context of the currently ongoing global outbreak, we really mean highly pathogenic avian influenza A virus H5N1. (This virus was first detected in a commercial goose farm in Guangdong province China, in 1996.
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Thijs Kuiken
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3/n It there belongs to the so-called A/goose/Guangdong/1/96 lineage.) I will take its name apart and discuss the separate pieces: i. influenza A virus (rather than B, C, or D) ii. avian (rather than human, swine, equine, or bat) iii. H5 (rather than H1 to H18)
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4/n iv. N1 (rather than N1 to N11) v. highly pathogenic (rather than low pathogenic)
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5/n Let’s start: i. Influenza viruses can be divided into four major types: A (mainly in birds, swine, horses, humans, and bats), B (in humans and seals), C (in swine and humans), and D (in cattle). We are here dealing with an influenza A virus.
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6/n ii. Most influenza A viruses (except bat influenza A viruses) are considered to originate from wild aquatic birds, particularly species of dabbling ducks and gulls, in which they are endemic.
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7/n (Endemic means that the virus persists at a consistent level within a population with fairly predictable rates of infection and spread.)
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Thijs Kuiken
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8/n However, they can spill over into chickens and other poultry species kept in farms and, if not dealt with appropriately, become endemic in poultry populations. The influenza A viruses that are endemic in birds, either wild or domestic, are called avian influenza A viruses.
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9/n From birds, avian influenza A viruses can spill over into mammals. Usually, there is no or only limited mammal-to-mammal transmission. On rare occasions, however, avian influenza A viruses persist in mammalian populations and become genetically adapted to them.
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10/n In that case, they are given the name of the species to which they have adapted: human influenza A viruses in people, swine influenza A viruses in pigs, and equine influenza A viruses in horses.
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11/n iii. Influenza A viruses have two kinds of proteins projecting from their surface. One is labelled H (for hemagglutinin), and there are 16 different H subtypes, H1 to H16. (In addition, bat influenza A viruses have H17 and H18.) We are here dealing with H5.
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Thijs Kuiken
@thij​​




Thijs Kuiken
@thijskuiken
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11/n iii. Influenza A viruses have two kinds of proteins projecting from their surface. One is labelled H (for hemagglutinin), and there are 16 different H subtypes, H1 to H16. (In addition, bat influenza A viruses have H17 and H18.) We are here dealing with H5.
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Thijs Kuiken
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12/n iv. The other surface protein is labelled N (for neuraminidase), and there are 9 different N subtypes, N1 to N9. (In addition, bat influenza A viruses have N10 and N11.) We are here dealing with N1, but the virus has switched to other N subtypes in past, e.g. H5N8 and H5N6.
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Thijs Kuiken
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13/n v. There is a special classification of avian influenza A viruses into low pathogenic or highly pathogenic. This classification refers only to the pathogenicity (that is, ability to cause disease) of these viruses in chickens, not in other species of birds, not in mammals.
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Thijs Kuiken
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14/n Historically, the vast majority of avian influenza A viruses detected in wild aquatic birds were low pathogenic (but see below).
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15/n In poultry, however, and particularly in intensive poultry production systems, low pathogenic avian influenza A viruses of the subtypes H5 and H7 can mutate into highly pathogenic avian influenza A viruses. We are here dealing with a highly pathogenic form.
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Thijs Kuiken
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16/n So, to put the name of the virus we are dealing with in the currently ongoing global outbreak together again, it is highly pathogenic avian influenza A virus H5N1.
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Thijs Kuiken
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17/n Besides being endemic in poultry populations in some countries, it has spilled over into wild aquatic birds and appears to have become endemic in them also. This means that we nowadays can detect both low and highly pathogenic avian influenza A viruses in wild birds.
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Thijs Kuiken
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18/n Besides spilling over into wild aquatic birds, it has spilled over into many other species of birds (>300 bird species in total). It also has spilled over into many species of mammals (>50 in total), including, since March 2024, in cattle in the USA.
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Thijs Kuiken
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19/n However, because the virus has *not* become endemic in any of the mammal species (including cattle) so far and has not shown clear genetic adaptation to those species, the appropriate name remains highly pathogenic avian influenza A virus H5N1.
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Thijs Kuiken
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20/n Webster et al. 1992: Evolution and ecology of influenza A viruses (DOI: 10.1128/mr.56.1.152-179.1992).
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Thijs Kuiken
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21/n Xu et al. 1999: Genetic characterization of the pathogenic influenza A/Goose/Guangdong/1/96 (H5N1) virus: similarity of its hemagglutinin gene to those of H5N1 viruses from the 1997 outbreaks in Hong Kong (doi: 10.1006/viro.1999.9820).
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Thijs Kuiken
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22/n Olsen et al. 2006: Global patterns of influenza A virus in wild birds (doi: 10.1126/science.1122438). Brunotte et al. 2016: Chiropteran influenza viruses: flu from bats or a relic from the past? (doi: 10.1016/j.coviro.2016.02.003).
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Thijs Kuiken
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23/n Dhingra et al. 2018: Geographical and historical patterns in the emergences of novel highly pathogenic avian influenza (HPAI) H5 and H7 viruses in poultry (doi: 10.3389/fvets.2018.00084).
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Thijs Kuiken
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24/n Pohlmann et al. 2022: Has epizootic become enzootic? Evidence for a fundamental change in the infection dynamics of highly pathogenic avian influenza in Europe, 2021 (doi: 10.1128/mbio.00609-22).
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25/n Klaassen & Wille 2023: The plight and role of wild birds in the current bird flu panzootic (doi: 10.1038/s41559-023-02182-x). European Food Safety Authority et al. 2023: Avian influenza overview September-December 2023 (doi: 10.2903/j.efsa.2023.8539).
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26/n Kuiken et al. 2006: Host species barriers to influenza virus infections (doi: 10.1126/science.1122818).
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[Treyfish]

Agricultural and health officials monitor Bird flu's spread to Michigan dairy herds.

WKAR Public Media | By Wali Khan
Published April 16, 2024 at 3:54 PM EDT​

​​​​​​State agriculture officials say experts across the nation are assessing the avian influenza outbreak among dairy herds.

The virus has been reported in herds in Ionia, Isabella, Ottawa, and Montcalm counties. Each herd is estimated to be more than 500 animals. The first infection was traced to Texas, where the virus is also being detected in herds.

The flu virus is being monitored on the “federal, state and local” level, according to State Veterinarian Nora Wineland. “We've identified additional suspected cases and those were reported to and are by local veterinarians, and producers and samples were submitted to the Michigan State University Veterinary Diagnostic Lab for testing."

Wineland said the pattern of reporting and testing is expected to continue, “leading to the potential for more cases to be identified in the future.”...
:tiphat:

https://www.wkar.org/wkar-news/2024...itor-bird-flus-spread-to-michigan-dairy-herds
​

 

[Pathfinder]

​bioRxiv

Posted April 16, 2024.

Highly Pathogenic Avian Influenza A (H5N1) clade 2.3.4.4b Virus detected in dairy cattle

Xiao Hu, Anugrah Saxena, Drew R. Magstadt, Phillip C. Gauger, Eric Burrough, Jianqiang Zhang, Chris Siepker, Marta Mainenti, Patrick Gorden, Paul Plummer, Ganwu Li
doi: https://doi.org/10.1101/2024.04.16.588916

This article is a preprint and has not been certified by peer review [what does this mean?].

Abstract

The global emergence of highly pathogenic avian influenza (HPAI) A (H5N1) clade 2.3.4.4b viruses poses a significant global public health threat. Until March 2024, no outbreaks of this virus clade had occurred in domestic cattle. We genetically characterize HPAI viruses from dairy cattle showing an abrupt drop in milk production. They share nearly identical genome sequences, forming a new genotype B3.13 within the 2.3.4.4b clade. B3.13 viruses underwent two reassortment events since 2023 and exhibit critical mutations in HA, M1, and NS genes but lack critical mutations in PB2 and PB1 genes, which enhance virulence or adaptation to mammals. The PB2 E627K mutation in a human case underscores the potential for rapid evolution post-infection, highlighting the need for continued surveillance to monitor public health threats.
...

https://www.biorxiv.org/content/10.1101/2024.04.16.588916v1

 

[Pathfinder]

Animal and Plant Health Inspection Service

Detection of Highly Pathogenic Avian Influenza (H5N1) in
Dairy Herds: Frequently Asked Questions

Updated April 16, 2024
...

What is the appropriate nomenclature for this virus,
now that it has appeared in dairy cows?

From USDA’s perspective, highly pathogenic avian
influenza or H5N1 are the most scientifically accurate
terms to describe this virus. This is also consistent with
what the scientific community has continued to call the
virus after it has affected other mammals. As a
reminder, genomic sequencing of viruses isolated from
cattle indicates there is no change to this virus that
would make it more transmissible to or between
humans, and the CDC considers risk to the public to be
low at this time. However, people with more exposure
to infected animals do have a greater risk of infection.
Since the virus is not highly pathogenic in mammals,
H5N1 is the most fitting of the two scientifically correct
options. It is important to note that “highly pathogenic”
refers to severe impact in birds, not necessarily in
humans or cattle.
...

https://www.aphis.usda.gov/sites/default/files/hpai-dairy-faqs.pdf

​

 

[Pathfinder]

Animals susceptible to H5N1 highly pathogenic avian influenza (HPAI)
...
Insects

Among non-vertebrate species, research has shown that house flies (Musca domestica) and blow flies (Calliphora nigribarbis) could act as mechanical transmitters of H5N1 HPAI and other avian influenza viruses (AIV). The possible role of other insects such as darkling beetles in the transmission of AIV is under investigation.
...

https://inspection.canada.ca/animal...-to-h5n1-hpai/eng/1375992449648/1375992451039

 

[Pathfinder]

Hattip to Shiloh for posting this article:
GO TO POST

Excerpt:
​...
Farmers have been told to discard milk from infected cows, though the USDA, the Food and Drug Administration, and the CDC all routinely state that they believe pasteurization would kill the viruses. But that is based on work done on other pathogens, not H5N1.

STAT has been pressing the USDA about whether research is being done to test the effect of pasteurization on H5N1-contaminated milk. USDA officials deferred questions to the FDA, saying it is responsible for food safety. The FDA said the work had not yet been done. When asked whether the research was underway, and when results would be available, the FDA did not reply.

“I am shocked we still don’t have the data on pasteurization,” Bright said. “The public deserves to know what experiments are being done [and] when can we expect data from those.”
...

https://www.statnews.com/2024/04/18/h5n1-bird-flu-scientists-want-usda-genetic-data-faster/

 

[Commonground]

Helen Branswell

@HelenBranswell

1h
3 more dairy herds have been confirmed to have cows infected with #H5N1 #birdflu. Texas, Kansas & Michigan each notched up one more infected herd. National total is now 32. Seems to be a 2-3 day lag between lab confirmation & posting by
@USDA
. https://aphis.usda.gov/livestock-poultry-disease/avian/avian-influenza/hpai-detections/livestock…



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[sharon sanders]

At above link - 32 entries with the last 3 being:

State Species Date confirmed by NVSL
Michigan Dairy Milking Cattle 4/17/2024
Texas Dairy Milking Cattle 4/17/2024
Kansas Dairy Milking Cattle 4/17/2024

 

[Pathfinder]

USDA confirms cow-to-cow transmission a factor in bird flu spread

Fargo, ND, USA / The Mighty 790 KFGO | KFGO
Thomson Reuters
Apr 19, 2024 | 2:09 PM

By Tom Polansek

CHICAGO (Reuters) – The U.S. Department of Agriculture said this week that cow-to-cow transmission is a factor in the spread of bird flu in dairy herds, but it still does not know exactly how the virus is being moved around.
...
“Those of us that have worked with influenza for a long time were fairly quickly saying, ‘Yep it moves cow to cow,'” Jim Lowe, an associate dean at the University of Illinois College of Veterinary Medicine, said on Friday. “You can’t explain the epidemiology any other way.”

Wild migratory birds are believed to be the original source of the virus. But the USDA said its investigation into cow infections “includes some cases where the virus spread was associated with cattle movements between herds.” There is also evidence the virus spread from dairy cattle premises “back into nearby poultry premises through an unknown route,” the department said.

The USDA said cows shed the virus in milk at high concentrations, so anything that comes in contact with unpasteurized milk may spread the disease. Respiratory transmission is not considered a primary way for the virus to spread in cattle, the department added.
...
https://kfgo.com/2024/04/19/usda-confirms-cow-to-cow-transmission-a-factor-in-bird-flu-spread/
​

 

[sharon sanders]

FluTrackers, April 3, 2024 link

"At this time, APHIS is not requiring testing. Testing may be done on a voluntary basis and is a tool producers may use to help manage this disease or reduce the risk of introducing the disease." link

This policy is ridiculous. There should be massive widespread testing to, at the very least, quantify the size of the problem.

Irresponsible and against standard outbreak surveillance protocol.
​

Main street media taking up the issue. Please see from our news thread on this topic: link

​
Stat News, April 18, 2024 - USDA faulted for disclosing scant information about outbreaks of H5N1 avian flu in cattle (hat tip Shiloh)

New York Times, April 19, 2024 - Scientists Fault Federal Response to Bird Flu Outbreaks on Dairy Farms (hat tip Treyfish)​

 

[sharon sanders]

FluTrackers does not sell ad space and we do not make any $ from clicks on this site.

 

[Pathfinder]

H5N1 influenza: From avian to bovine to feline and beyond

By Emily Singler, VMD - 4/19/2024

In March 2024, dairy and poultry veterinarian Kay Russo, DVM, MAHM, DACPV, was contacted by a fellow veterinarian who was working up cattle on a dairy farm in Texas.

The cattle were displaying respiratory and gastrointestinal signs including high fevers, respiratory distress, decreased rumination, and significantly decreased milk production. They had high morbidity rates and low mortality rates—and they were testing negative for all the usual suspects.

Since the farm’s veterinarian had already ruled out bovine syncytial virus, coronavirus, salmonella, and bovine viral diarrhea, Russo knew to be on the lookout for something atypical. She reports that it was the combination of signs, including the mammary involvement, that really made her consider influenza.

That’s when she posed a question that would have an ominous answer. “What are the birds doing on the farms?” she asked, referring to wild birds such as pigeons and grackles.

Then answer came back, “the birds are all dead.”

And those who hadn’t died yet were showing severe neurologic signs.

Russo quickly advised those who were in the field to obtain as many samples as possible from the birds to send out for testing at the National Veterinary Services Laboratories.

When those samples came back positive for H5N1 (one of the two strains associated with highly pathogenic avian influenza or HPAI), Russo felt a pit in her stomach. She knew the cattle needed to be tested as well.

On March 21, 2024, the first sample from the dairy cattle came back positive for H5N1.
...
Shortly after Russo received the H5N1 diagnosis in the farm’s cattle, barn cats on both affected dairy farms started showing respiratory and neurologic signs.
...
Unfortunately, all five of these cats died. Samples from the cats were sent for testing and came back positive for H5N1.
...

https://www.aaha.org/publications/n...za-from-avian-to-bovine-to-feline-and-beyond/
--------------------------------------------------------------

UN, WHO address public health concern over avian flu transmission to humans

April 18, 2024
Kristen Coppock, MA, Associate Editorial Director
...
Globally, there were 887 cases of human H5N1 infection—from January 1, 2003, to February 26, 2024—of which 52% were fatal, according to WHO.5 The H5N1 case in Texas is the United States’ first reported human infection of 2024. It is also the second human case to ever be confirmed in the US, with the previous infection occurring in 2022, in Colorado.4

According to Kay Russo, DVM, MAHM, DACPV, an industry veterinarian, who has worked as a private dairy practitioner, WHO’s documented mortality rate may be higher than the actual mortality rate in humans because of a bias related to the severity of illness in those who sought care. However, she noted, we still need to have a healthy respect for what this virus is capable of. “The human cases in this current dairy situation are underrepresented due to a lack of testing,” Russo said in an interview with dvm360®.
...
Russo emphasized that early detection and intervention in the form of antivirals are critical to avoid any severe health outcomes from this virus. “Should this virus develop the ability to spread from human to human, [other] individuals living in the household of the infected individual may be at risk. Testing and proper follow-up are strongly encouraged by the CDC. All testing is anonymous,” Russo said.
...


https://www.dvm360.com/view/who-avian-flu-transmission-to-humans-is-a-public-health-concern

 

[Commonground]

U.S. Could Vaccinate a Fifth of Americans in a Bird Flu Emergency
April 20, 2024, 4:00 am EDT

Two clinical trials of the vaccine likely to be used, under way since last year, have yet to produce data.
-snip-

The strain of avian flu known as H5N1 has been circulating among birds in the U.S. since late 2021, and is known only to have infected two people in the country, including a Texas dairy worker last month. U.S. officials aren’t near pulling the trigger on plans to roll out emergency vaccinations.
-snip-

Federal officials now say that in the event of an H5N1 pandemic, they would be able to supply a few hundred thousand doses within weeks, followed by 10 million doses using materials already on hand, and then another 125 million within about four months. People would need two doses of the shot to be fully protected.

A spokesperson for Administration for Strategic Preparedness & Response, the HHS division responsible for pandemic preparations, said that if needed, the agency would work with manufacturers to “to ramp up production to make enough vaccine doses to vaccinate the entire U.S. population.” But the agency didn’t articulate plans beyond those first 135 million doses, which would be enough to inoculate roughly 68 million people in a country of more than 330 million...

...https://www.barrons.com/articles/bird-flu-h5n1-human-vaccine-supply-f1f8c6e7
​



​

 

[Commonground]

Next pandemic likely to be caused by flu virus, scientists warn
​Sat 20 Apr 2024 04.52 EDT

-snip-
An international survey, to be published next weekend, will reveal that 57% of senior disease experts now think that a strain of flu virus will be the cause of the next global outbreak of deadly infectious illness.

The belief that influenza is the world’s greatest pandemic threat is based on long-term research showing it is constantly evolving and mutating, said Cologne University’s Jon Salmanton-García, who carried out the study. “Each winter influenza appears,” he said. “You could describe these outbreaks as little pandemics. They are more or less controlled because the different strains that cause them are not virulent enough – but that will not necessarily be the case for ever.”

-snip-
Details of the survey – which involved inputs from a total of 187 senior scientists – will be revealed at European Society of Clinical Microbiology and Infectious Diseases (ESCMID) congress in Barcelona next weekend.​..

Complete article: https://www.theguardian.com/world/2...ely-to-be-caused-by-flu-virus-scientists-warn
​

 

[sharon sanders]

USDA confirms cow-to-cow transmission a factor in bird flu spread

Fargo, ND, USA / The Mighty 790 KFGO | KFGO
Thomson Reuters
Apr 19, 2024 | 2:09 PM

By Tom Polansek

CHICAGO (Reuters) – The U.S. Department of Agriculture said this week that cow-to-cow transmission is a factor in the spread of bird flu in dairy herds, but it still does not know exactly how the virus is being moved around.
...
“Those of us that have worked with influenza for a long time were fairly quickly saying, ‘Yep it moves cow to cow,'” Jim Lowe, an associate dean at the University of Illinois College of Veterinary Medicine, said on Friday. “You can’t explain the epidemiology any other way.”

Wild migratory birds are believed to be the original source of the virus. But the USDA said its investigation into cow infections “includes some cases where the virus spread was associated with cattle movements between herds.” There is also evidence the virus spread from dairy cattle premises “back into nearby poultry premises through an unknown route,” the department said.

The USDA said cows shed the virus in milk at high concentrations, so anything that comes in contact with unpasteurized milk may spread the disease. Respiratory transmission is not considered a primary way for the virus to spread in cattle, the department added.
...
https://kfgo.com/2024/04/19/usda-confirms-cow-to-cow-transmission-a-factor-in-bird-flu-spread/
​

Please see:

USDA - Detection of Highly Pathogenic Avian Influenza (H5N1) in Dairy Herds: Frequently Asked Questions Updated April 16, 2024
​

 

[sharon sanders]

The US has based its flu pandemic vaccine preparations on H5N1. I believe they have had seed material for an H5N1 for years. Of course, strains are different so I have no idea how well the seed vaccines match any current H5N1 strain.