USDA Announces the Detection of H5N1 in a Backyard Pig

• The pig was from a small herd of swine (5 pigs) that shared water sources, housing and equipment with sheep, goats, and a small poultry flock.
• The poultry tested positive for H5N1 and were de-populated. 
  
• Having been noted to be scavenging on dead wild birds, the pigs were euthanized and tested out of an abundance of caution. 
• Sheep and goats at the farm are under surveillance.
• The Influenza A strain isolated from the infected poultry on-farm is the circulating wild bird strain, NOT the one occurring in dairy cattle in the US.

A western Canadian veterinary virologist described the situation this way: “Think of the backyard pig in this case as another scavenger mammal! We have found H5N1 in other species (e.g. skunks) in the west, and this detection in the backyard pig in Oregon is not surprising, given the circumstances”.

18th December 2024. 315 confirmed influenza A(H5N1) infections in cattle in 3 states: California, Nevada and Texas. The total is currently 865 confirmed cases in 16 states in cattle. LINK

10th December 2024. 249 confirmed new cases in California and Nevada in the last 30 days in cattle. In total there were 742 cases in cattle in 16 states and 744 cases in all livestock in 17 states LINK. A dairy herd in Colorado has been quarantined again after a positive H5N1 test - this herd is not counted again as part of the outbreaks on the USDA website LINK.

4th November 2024. 4th November 2024. 160 confirmed new cases in 3 states in the last 30 days. 442 confirmed cases in total LINK.

 9th September 2024. With 6 new cases reported over the past 30 days, the incidence rate of new HPAI cases in U.S. dairy herds seems to be slowing. Currently 197 infected herds have been reported, across 14 states, with California being the most recent new state to report detections. LINK

No HPAI cases have been reported in U.S. beef cattle, and no HPAI cases have been reported in Canadian dairy or beef cattle. LINK

26 August 2024. 20 confirmed cases of HPAI H5N1 in the last 30 days, with 5 states affected. LINK

13 August 2024. 2 herds, in Colorado and Idaho, with confirmed cases in dairy milking cows. LINK

12th July 2024. Influenza A detected in Oklahoma Dairy Cattle, with Oklahoma becoming the 13th U.S. state to report infected dairy herd.  LINK

May 24, 2024. Influenza A detection in U.S. dairy cattle. 63 herds in 9 states. LINK

 May 22, 2024. Influenza A detections in U.S. dairy cattle map: 52 herds in 9 states LINK

 May 10. Influenza A detections in U.S. dairy cattle map: 42 herds in 9 states   LINK

 April 19 2024. Influenza A detections in U.S. dairy cattle map LINK

April 2, 2024. Influenza A detection in Idaho dairy cattle LINK

April 1,  2024. Influenza A detection in New Mexico dairy cattle LINK

March 29, 2024 HPAI detection in Michigan dairy cattle LINK

HPAI detection in Idaho dairy cattle LINK 

March 25, 2024  HPAI detection in Texas and Kansas dairy cattle LINK

May 24, 2024

USDA’s Food Safety and Inspection Service (FSIS), as part of its ongoing efforts to ensure the safety of the food supply, has conducted tests on beef tissue from 96 cull dairy cows condemned at select FSIS-inspected facilities. Meat from condemned cows is prohibited from entering the food supply. On May 22, 2024, viral particles were detected in tissue samples, including muscle, from one cow. To date, samples from 95 cows have tested negative for viral particles. No meat from these dairy cattle entered the food supply.

As part of this study, FSIS collected multiple tissues, including muscle samples from the diaphragm, at FSIS-inspected slaughter facilities from cull dairy cattle that have been condemned for systemic diseases. The samples were analyzed by APHIS using PCR to determine presence of viral particles. PCR testing does not differentiate between live virus or fragments.

FSIS and APHIS are working together to conduct traceback, including notification to the producer to gather further information.

FSIS personnel identified signs of illness in the positive animal during post-mortem inspection and prevented the animal from entering the food supply. This type of inspection is part of routine FSIS operations. These actions provide further confidence that the food safety system we have in place is working.

Further updates will be provided as testing is completed.  LINK

December 12, 2024. A child that became sick (fever and vomiting) after drinking raw milk was tested for influenza A - it was negative. Ten additional sick persons reported drinking raw milk - there was no positive tests at the time of reporting. Original news article LINK and update LINK

December 9, 2024. There were 35 confirmed human cases of avian influenza A(H5N1) associated with cattle and 21 confirmed human cases associated with poultry. There were an additional 2 human cases with unknown exposure to animals. The total is currently 58 human cases. LINK

A Californian child was affected with influenza A(H5N1) and had unknown exposure to animals LINK. The genome of the H5N1 could not be completely sequenced, but certain genes were sequenced and analyzed. These genes most closely resembled those of the B3.13 genotype from dairy cattle. LINK

The CDC is monitoring influenza in people and have not identified any unusual trends LINK.

September 9, 2024. CDC has confirmed a human case of avian influenza A(H5) ("H5 bird flu") reported by the state of Missouri. The case was identified through that state's seasonal flu surveillance system. The specimen was forwarded to CDC for confirmatory testing per usual protocols and confirmed yesterday. An investigation into the potential exposure is ongoing by the Missouri Department of Health and Senior Services (DHSS).
Case Information
Missouri DHSS reports that the patient, who was hospitalized, had underlying medical conditions, was treated with influenza antiviral medications, subsequently discharged, and has recovered. There is no immediate known animal exposure. No ongoing transmission among close contacts or otherwise has been identified.
This is the 14th human case of H5 reported in the United States during 2024 and the first case of H5 without a known occupational exposure to sick or infected animals. H5 outbreaks in cattle have not been reported in Missouri, but outbreaks of H5 have been reported in commercial and backyard poultry flocks in 2024. H5N1 bird flu has been detected in wild birds in that state in the past.
While other novel flu cases have been detected through the country's national flu surveillance system, this is the first time that system has detected a case of H5. Targeted H5-outbreak specific surveillance has been conducted as part of ongoing animal outbreaks and has identified all the other cases. In this case, the specimen from the patient originally tested positive for flu A, but negative for seasonal flu A virus subtypes. That finding triggers additional testing.
CDC continues to closely monitor available data from influenza surveillance systems, particularly in affected states, and there has been no sign of unusual influenza activity in people, including in Missouri.
Identification of the neuraminidase (the "N") in the patient specimen is pending further sequencing. Attempts to sequence the genome of the virus also are underway at CDC.
Based on available data, CDC's current assessment is that the risk to the general public from H5N1 remains low. CDC's recommendations related to H5 virus have not changed at this time. LINK

July 3rd, 2024.  A human case of highly pathogenic avian influenza (HPAI) A(H5) (“H5 bird flu”) virus infection in the United States has been identified in the state of Colorado. This is the fourth case associated with an ongoing multistate outbreak of A(H5N1) in dairy cows and the first in Colorado. Previous cases were reported in Texas (1) and Michigan (2). As with previous cases, the person is a worker on a dairy farm where cows tested positive for A(H5N1) virus. The person reported eye symptoms only, received oseltamivir treatment, and has recovered.  LINK

30th May, 2024. Second dairy farm worker infected with H5 avian flu in Michigan - The Centers for Disease Control and Prevention (CDC) today announced a third human illness from H5 avian influenza in a dairy farm worker, but unlike the earlier cases, the patient is experiencing respiratory symptoms. In a statement, the CDC said the latest sick dairy farm worker was exposed on a different farm than Michigan's earlier case. 

The patient reported symptoms, including cough without fever and eye discomfort with watery discharge, to local health officials. Michigan health officials are using a text-based monitoring system for people exposed to H5N1-infected cows.

Michigan's first patient experienced eye symptoms after a direct splash to the eye from infected milk, and the second patient had direct exposure to a sick cow. 
"Neither individual was wearing full personal protective equipment (PPE)," she said. "This tells us that direct exposure to infected livestock poses a risk to humans, and that PPE is an important tool in preventing spread among individuals who work on dairy and poultry farms."

The CDC had earlier issued interim PPE recommendations for dairy farm worker protection, and federal officials have encouraged states to provide PPE to farm workers. In new guidance, the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) yesterday issued PPE recommendations for people visiting H5N1-infected herds. LINK

 

22 May, 2024 - The Michigan Department of Health and Human Services (MDHHS) today announced an H5 avian flu case in a Michigan farm worker who had regular exposure to infected livestock, marking the third human case in the United States and the second related to the H5N1 outbreaks in dairy cattle. In a statement, MDHHS said the identification of the case came after the state's ongoing public health actions allowed farm workers to monitor and notify health officials if they develop symptoms. 
Officials didn't detail the patient's symptoms, but said they were mild and that the farm worker has recovered. The earlier patient from a Texas farm also had a mild illness, which consisted of conjunctivitis.     

April 1, 2024 - A person in the United States has tested positive for highly pathogenic avian influenza (HPAI) A(H5N1) virus (“H5N1 bird flu”), as reported by Texas and confirmed by CDC.

This person had exposure to dairy cattle in Texas presumed to be infected with HPAI A(H5N1) viruses. The patient reported eye redness (consistent with conjunctivitis), as their only symptom, and is recovering. The patient was told to isolate and is being treated with an antiviral drug for flu.

This infection does not change the H5N1 bird flu human health risk assessment for the U.S. general public, which CDC considers to be low. However, people with close or prolonged, unprotected exposures to infected birds or other animals (including livestock), or to environments contaminated by infected birds or other animals, are at greater risk of infection. LINK

CDC recommendations for humans to reduce risk of HPAI infection
1. Recommendations for the Public
People should avoid unprotected (not using respiratory or eye protection) exposures to sick or dead animals including wild birds, poultry, other domesticated birds, and other wild or domesticated animals, as well as with animal feces, litter, or materials contaminated by birds or other animals with suspected or confirmed HPAI A(H5N1) virus infection. People should not prepare or eat uncooked or undercooked food or related uncooked food products, such as unpasteurized (raw) milk, or raw cheeses, from animals with suspected or confirmed HPAI A(H5N1) virus infection (avian influenza or bird flu).

2. People exposed to HPAI A(H5N1)-virus infected birds or other animals (including people wearing recommended PPE) should monitor themselves for new respiratory illness symptoms, including conjunctivitis (eye redness), beginning after their first exposure and for 10 days after their last exposure.

3. Recommendations for Farmers; Poultry, Backyard Bird Flock, and Livestock Owners; and Worker Protection
To reduce the risk of HPAI A(H5N1) virus infection, poultry farmers and poultry workers, backyard bird flock owners, livestock farmers and workers, veterinarians and veterinary staff, and responders should avoid unprotected direct physical contact or close exposure with sick or dead birds or other animals, carcasses, feces, milk, or litter from sick birds or other animals potentially infected or confirmed to be infected with HPAI A(H5N1) virus. Farmers, workers, and responders should wear recommended PPE such as an N95 filtering facepiece respirator, eye protection, and gloves, and perform thorough hand washing after contact. (e.g., see: PPE recommended for poultry workers) when in direct contact with sick or dead birds or other animals, carcasses, feces, or litter from potentially infected birds or other animals, and when going into any buildings with or that have had sick or dead birds or other animals, carcasses, feces, or litter from potentially infected birds or other animals. Workers should receive training on and demonstrate an understanding of when to use PPE; what PPE is necessary; how to properly put on, use, take off, dispose of, and maintain PPE; and PPE limitations.

USDA’s National Veterinary Services Laboratories confirmed highly pathogenic avian influenza (HPAI) in neonatal goat kids that demonstrated neurologic signs from a Minnesota backyard premises recently affected with HPAI.

The goats on the premises shared the same pasture and sole water source with infected ducks and chickens. The goats began to kid only days after the birds were depopulated. Of 10 goat kids that have died, ranging from 5 days to 9 days of age, five goat kids between 7 and 9 days of age have tested positive on brain and other tissues for H5N1 clade 2.3.4.4b virus. Sequencing showed that isolates from the first goat and infected poultry were highly related.

For more information  LINK

 

Information document for veterinarians with regards to influenza A(H5N1) and cats. LINK

Testing of sick cats on some affected dairy farms in Texas and Kansas for H5N1 has so far yielded three H5N1 (HPAI) positives. This isn’t the first time the virus has been detected in cats (e.g. they’ve been reported before in the US, Poland, and South Korea) but does suggest they should be kept away from cattle. LINK

The National Veterinary Services Laboratories (NVSL) confirmed the detection of Highly Pathogenic Avian Influenza (HPAI) H5N1 in alpacas from a premises where HPAI-affected poultry were depopulated in May 2024. While this HPAI confirmation is not unexpected due to the previous HPAI detection on the premises, the high amount of virus in the environment, and co-mingling of multiple livestock species on-farm, it is the first HPAI detection in alpacas.

NVSL has confirmed that the viral genome sequence for these samples is the same sequence currently circulating in dairy cattle (B3.13), which is consistent with sequences from the depopulated poultry on this premises. (NVSL PCR confirmation was completed on May 16. APHIS reported the confirmation to the World Organisation for Animal Health and on the HPAI livestock website upon completion of additional gene sequencing, per APHIS policy for disease detections in new species.)

26th June 2024 In today's update from the USDA, 5 more domestic cats (4 in Texas, 1 in Minnesota) have been added to the list of H5N1 infected mammals, along with with 2 raccoons, 1 striped skunk, and a red fox. For the first time in 3 weeks no additional mice were added to the list.

USDA-APHIS host an updated map of these non-livestock detections LINK

Biosecurity Update for On-farm Dairy Service Providers LINK

 

Dairy Biosecurity Recommendations: HPAI and more LINK

 

proAction: Canadian Dairy Quality Assurance Program Biosecurity Module LINK

 

USDA-APHIS Secure Milk Supply (SMS) Dairy Biosecurity Resources LINK

 

CAHSS Biosecurity Recommendations for Canadian Dairy Herds LINK

Canadian Food Inspection Agency: Highly pathogenic avian influenza (HPAI) in livestock LINK

 

USDA-APHIS: Detection of Highly Pathogenic Avian Influenza in Dairy Herds: Frequently Asked Questions LINK

 

USDA-APHIS: Questions and Answers Regarding Milk Safety During Highly Pathogenic Avian Influenza (HPAI) Outbreaks   LINK

• Increase avian influenza surveillance in domestic and wild birds.
• Enhance surveillance for early detection in cattle.
• Include HPAI as a differential diagnosis in non-avian species.
• Notify cases of HPAI in all animals to WOAH.
• Implement preventive and early response measures to break transmission pathways among animals.
• Protect humans in close contact with or handling sick animals.
• Avoid implementing unjustified trade restrictions.

LINK 

• USDA reported no real evidence virus is replicating inside the cows aside from the udder
• hypothesis that it may be moving between cattle by indirect contact (e.g. milking equipment) and opposed to, say respiratory route like coughing/fecal shedding.
• also a hypothesis that viruses in all affected US cows to date are so similar that they may have originated from one herd. So potentially what we've seen so far for H5N1 disease in US dairy cows could reflect one spillover event from birds, or a couple of closely related ones, as opposed to multiple independent events in which multiple infected birds contacted multiple herds.

LINK