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Highly pathogenic avian influenza (HPAI) in cattle: Guidance for private veterinarians
The following guidance serves as a reference for private veterinarians to collect and submit samples for highly pathogenic avian influenza (HPAI) in dairy cattle, both for suspect and non-clinical animals. It also includes information on reporting requirements for suspect cases of HPAI in cattle.
HPAI is a federally reportable disease in any species. If you suspect HPAI in cattle, report it to your local CFIA district office.
HPAI is also reportable in some provinces and territories. Find provincial/territorial reporting requirements and contact information in the appendix. On this page
Based on the recent detections in the United States (US), affected dairy cattle are most commonly in the second lactation or greater and >150 days in milk. Clinical signs of HPAI infections that have been reported in dairy cattle in the US include:
Clinical signs in some cattle improve over 4 to 7 days, but some do not recover in milk production.
Veterinarians are required to contact their local CFIA district office and where required, the provincial or territorial Chief Veterinary Officer, if they highly suspect an HPAI infection in cattle. Criteria that contribute to a higher level of suspicion include:
Private veterinarians are responsible for sample collection both for suspect cases and in cattle with no clinical signs.
Private veterinarians may send samples to a CAHSN laboratory that is approved to test samples in domestic animals. These are the same laboratories that have been testing poultry samples during the current H5N1 HPAI outbreak. For more information on approved CAHSN laboratories, contact your local CFIA district office.
Laboratory testing fees
Until further notice, CFIA will cover the fees for laboratory testing at any CAHSN laboratory that is approved to test samples in domestic animals. CFIA does not pay for associated veterinary fees for sample collection or shipment to the lab.
Sampling guidance
Samples may be submitted from lactating dairy cows, non-lactating dairy cattle (dairy calves, heifers and dry cows) as well as suspect cases and non-clinical animals.
For herds where HPAI is suspected, include samples from up to 10 clinically affected animals.
Samples must be refrigerated until they are submitted to the lab. Each sample must be individually labelled with the animal identification number.
Lactating dairy cattle
Milk is the only sample required for lactating dairy cattle. Cows shed the highest level of virus in their milk, which makes milk the ideal sample to test.
Aseptically collect up to 10 ml total sample volume from all 4 quarters into a sterile plastic specimen container with a secure lid (for example, screwed).
Non-lactating dairy cattle
Nasal swabs are the only sample required for non-lactating dairy cattle.
Use a single sterile swab (synthetic fibre swabs only) to sample both nostrils. Ensure the mucosa in the nasal passage with the swab. After both nasal passages have been sampled, gently agitate the swab in the Universal Transport Medium (UTM). Do not leave the swab in the UTM but instead swirl the swab into the UTM tube and thoroughly squeeze out the fluid against the side of the tube. Discard the swab.
CFIA's response to a suspect case report
When a suspect case is reported to a CFIA district office, CFIA staff will collect basic information, including premises location, species/signalment/history of suspect animal(s), presence of other livestock species on the premises and reason for HPAI suspicion. CFIA may share this information with the Chief Veterinary Officer in your province or territory.
CFIA staff will provide guidance on sampling and information on where to submit samples for testing.
For the most up-to-date information on HPAI in livestock in Canada, refer to Highly pathogenic avian influenza (HPAI) in livestock.
Results
Results are reported back to the submitting veterinarian by the CAHSN lab. For suspect case submissions, the private veterinarian is required to report negative test results back to the district office upon receipt. Samples returning non-negative results are forwarded to the CFIA's National Centre for Foreign Animal Disease for confirmatory testing. Notification to the submitting veterinarian may be delayed until confirmatory testing is complete.
Understanding negative test results
The HPAI screening test is a PCR (polymerase chain reaction). A negative test indicates no detection of influenza A virus in the sample. A negative test on a cow with no clinical signs typically means no HPAI infection.
Rarely, a false negative result occurs when the cow is infected, but HPAI is not detected by the test. Possible causes may include poor sampling technique, or if the cow is not yet shedding high levels of HPAI virus, for instance if the cow was infected very recently.
CFIA's response to a positive case
CFIA's response to detections of HPAI in cattle differs from the leading role CFIA plays for HPAI detections in domestic birds. Currently, CFIA's role for HPAI in cattle continues to be one of science advice, diagnostic support and international reporting. The CFIA collaborates with the provinces, territories and industry to promote consistency in support of the management of this disease.
Together with the provinces, territories and industry, the CFIA works to reduce the risk of HPAI transmission from an affected farm to other premises by recommending that:
For more information about the response in your area, contact your provincial or territorial Chief Veterinary Officer.
The CFIA will continue to reassess its position as new information becomes available.
Additional information
Transmission
Epidemiologic and genomic analysis suggests a single spillover event from wild birds with subsequent cow-to-cow transmission. Evidence suggests cow-to-cow transmission may occur through milk via fomites. However, other means of transmission are being considered. Non-clinical animals can also shed the virus in their milk, indicating that testing lactating animals' pre-movement is valuable in reducing between-farm disease transmission risk. Many herds infected with HPAI have a history of introduction of new animals from an affected area or herd.
The United States Department of Agriculture (USDA) reports lateral transmission from affected dairy herds to nearby poultry flocks based on epidemiologic and genomic analysis. Transmission is suspected to be via fomites (humans and/or equipment).
Personal safety
Avian influenza viruses, such as the highly pathogenic A(H5N1) currently circulating in wild birds in Canada, can, on rare occasions, cause disease in humans. Canada has never reported a locally acquired case of HPAI A(H5N1) in a person and the risk of avian influenza transmission to humans remains low.
People in contact with animals, including cattle and animal products, suspected or confirmed to be infected with avian influenza, or those exposed to highly contaminated environments, should take extra precautions to protect themselves by wearing personal protective equipment (PPE). This includes face masks, non-ventilated goggles, gloves, coveralls and boots. Boots, coveralls and other reusable PPE should be fully cleaned and disinfected between farms. Disposable gloves and face masks should be discarded on farm in a sealed bag.
The Public Health Agency of Canada's (PHAC) website has more information for people in contact with potentially infected animals or heavily contaminated environments: Infection prevention recommendations for individuals involved in animal outbreak situations.
Additionally, PHAC has partnered with the Canadian Centre for Occupational Health and Safety to provide advice on how to protect against avian influenza at work. For more information, please visit How to protect yourself from avian influenza A(H5N1) at work.
Additional information on avian influenza A (H5N1) in people is available from the Public Health Agency of Canada.
Biosecurity
To prevent exposure and spread of HPAI in cattle, producers and veterinarians should continue to follow good biosecurity measures, such as those outlined in the National Biosecurity Standards (Animal biosecurity). Dairy producers are required to adhere to biosecurity plans outlined in Dairy Farmers of Canada's proAction program.
In addition to emphasizing the value of good routine biosecurity practices to their clients, veterinarians are encouraged to highlight the following:
For further information on biosecurity practices to keep livestock safe, contact your provincial or territorial Chief Veterinary Officer.
Appendix – Provincial and territorial reporting requirements and contact information
Provinces and territories where HPAI in cattle is a reporting requirement
British Columbia
BC Chief Veterinary Officer
(604) 556-3003
Chief.Veterinarian@gov.bc.ca
Saskatchewan
Dr. Wendy Wilkins
(306) 798-0253
wendy.wilkins@gov.sk.ca
Manitoba
Manitoba Chief Veterinary Officer
(431) 323-5638
cvo-eoc@gov.mb.ca
Ontario
Dr. Greg Worley
(519) 826-3577
Greg.Worley@ontario.ca
Prince Edward Island
Dr. Jill Wood
(902) 370-4923
jswood@gov.pe.ca
Quebec
1 844 ANIMAUX (1 844 264-6289)
animaux@mapaq.gouv.qc.ca
Newfoundland and Labrador
Dr. Beverly Dawe
(709) 637-2042
beverlydawe@gov.nl.ca
Yukon
Dr. Mary Vanderkop
(867) 456-5582
mary.vanderkop@yukon.ca
Provinces and territories where HPAI in cattle is not a reporting requirement
Alberta
Alberta Chief Veterinary Officer
(780) 427-3448
Chief.Prov.Vet@gov.ab.ca
New Brunswick
Dr. Nicole Wanamaker
(506) 433-0493
nicole.wanamaker@gnb.ca
Nova Scotia
Dr. Wilma Schenkels
(902) 890-2941
Dr.Wilma.Schenkels@novascotia.ca
Northwest Territories
Dr. Naima Jutha
(867) 767-9237 ext. 53232
Naima_Jutha@gov.nt.ca
NunavutN/A
Related links
The following guidance serves as a reference for private veterinarians to collect and submit samples for highly pathogenic avian influenza (HPAI) in dairy cattle, both for suspect and non-clinical animals. It also includes information on reporting requirements for suspect cases of HPAI in cattle.
HPAI is a federally reportable disease in any species. If you suspect HPAI in cattle, report it to your local CFIA district office.
HPAI is also reportable in some provinces and territories. Find provincial/territorial reporting requirements and contact information in the appendix. On this page
- Checklist for sampling and testing for HPAI in cattle
- Clinical signs of HPAI in cattle
- Collecting and submitting samples
- Laboratory testing fees
- Sampling guidance
- CFIA's response to a suspect case report
- Results
- CFIA's response to a positive case
- Additional information
- Appendix
- Related links
- report suspicion to your local CFIA district office and province/territory when applicable (there is no reporting requirement when HPAI is not suspected)
- collect either milk samples from lactating animals or nasal swabs from non-lactating animals
- submit samples to an approved Canadian Animal Health Surveillance Network (CAHSN) laboratory; your district office can provide information on available CAHSN laboratories
- results are reported by your CAHSN lab
- non-negative results at a CAHSN lab will be sent to the CFIA's National Centre for Foreign Animal Disease for confirmatory testing
- for suspect case submissions, the private veterinarian is required to report negative test results back to the district office upon receipt
Based on the recent detections in the United States (US), affected dairy cattle are most commonly in the second lactation or greater and >150 days in milk. Clinical signs of HPAI infections that have been reported in dairy cattle in the US include:
- decreased feed intake with a simultaneous decrease in rumination and rumen motility
- respiratory signs, including clear nasal discharge
- sudden and significant decrease in milk production
- colostrum-like consistency of milk in one or more quarters
- dry manure or diarrhea
- lethargy
- dehydration
- fever
Clinical signs in some cattle improve over 4 to 7 days, but some do not recover in milk production.
Veterinarians are required to contact their local CFIA district office and where required, the provincial or territorial Chief Veterinary Officer, if they highly suspect an HPAI infection in cattle. Criteria that contribute to a higher level of suspicion include:
- clinical presentation consistent with the signs described above, without an alternative diagnosis
- an epidemiological link with a confirmed infected animal or herd/flock
- recent introductions into the herd within the last 30 days
- the discovery of dead or neurologic animals on the premises (for example, wild birds, raccoons, cats)
- potential for feed or water contamination by infected animals (for example, wild birds or mammals)
Private veterinarians are responsible for sample collection both for suspect cases and in cattle with no clinical signs.
Private veterinarians may send samples to a CAHSN laboratory that is approved to test samples in domestic animals. These are the same laboratories that have been testing poultry samples during the current H5N1 HPAI outbreak. For more information on approved CAHSN laboratories, contact your local CFIA district office.
Laboratory testing fees
Until further notice, CFIA will cover the fees for laboratory testing at any CAHSN laboratory that is approved to test samples in domestic animals. CFIA does not pay for associated veterinary fees for sample collection or shipment to the lab.
Sampling guidance
Samples may be submitted from lactating dairy cows, non-lactating dairy cattle (dairy calves, heifers and dry cows) as well as suspect cases and non-clinical animals.
For herds where HPAI is suspected, include samples from up to 10 clinically affected animals.
Samples must be refrigerated until they are submitted to the lab. Each sample must be individually labelled with the animal identification number.
Lactating dairy cattle
Milk is the only sample required for lactating dairy cattle. Cows shed the highest level of virus in their milk, which makes milk the ideal sample to test.
Aseptically collect up to 10 ml total sample volume from all 4 quarters into a sterile plastic specimen container with a secure lid (for example, screwed).
Non-lactating dairy cattle
Nasal swabs are the only sample required for non-lactating dairy cattle.
Use a single sterile swab (synthetic fibre swabs only) to sample both nostrils. Ensure the mucosa in the nasal passage with the swab. After both nasal passages have been sampled, gently agitate the swab in the Universal Transport Medium (UTM). Do not leave the swab in the UTM but instead swirl the swab into the UTM tube and thoroughly squeeze out the fluid against the side of the tube. Discard the swab.
CFIA's response to a suspect case report
When a suspect case is reported to a CFIA district office, CFIA staff will collect basic information, including premises location, species/signalment/history of suspect animal(s), presence of other livestock species on the premises and reason for HPAI suspicion. CFIA may share this information with the Chief Veterinary Officer in your province or territory.
CFIA staff will provide guidance on sampling and information on where to submit samples for testing.
For the most up-to-date information on HPAI in livestock in Canada, refer to Highly pathogenic avian influenza (HPAI) in livestock.
Results
Results are reported back to the submitting veterinarian by the CAHSN lab. For suspect case submissions, the private veterinarian is required to report negative test results back to the district office upon receipt. Samples returning non-negative results are forwarded to the CFIA's National Centre for Foreign Animal Disease for confirmatory testing. Notification to the submitting veterinarian may be delayed until confirmatory testing is complete.
Understanding negative test results
The HPAI screening test is a PCR (polymerase chain reaction). A negative test indicates no detection of influenza A virus in the sample. A negative test on a cow with no clinical signs typically means no HPAI infection.
Rarely, a false negative result occurs when the cow is infected, but HPAI is not detected by the test. Possible causes may include poor sampling technique, or if the cow is not yet shedding high levels of HPAI virus, for instance if the cow was infected very recently.
CFIA's response to a positive case
CFIA's response to detections of HPAI in cattle differs from the leading role CFIA plays for HPAI detections in domestic birds. Currently, CFIA's role for HPAI in cattle continues to be one of science advice, diagnostic support and international reporting. The CFIA collaborates with the provinces, territories and industry to promote consistency in support of the management of this disease.
Together with the provinces, territories and industry, the CFIA works to reduce the risk of HPAI transmission from an affected farm to other premises by recommending that:
- personal safety and on-farm biosecurity measures are observed as noted below
- cattle movement (particularly lactating cattle) onto and off the premises is stopped or limited until the herd has been cleared from the disease
- all milk from clinically affected animals does not enter the bulk tank and undergoes an inactivation process if being fed to other animals, or is appropriately discarded
- all milk from the bulk tank goes for pasteurization
- epidemiological information pertaining to the infected herd is collected
- local public health authorities are involved to further assess any potential human health risk
For more information about the response in your area, contact your provincial or territorial Chief Veterinary Officer.
The CFIA will continue to reassess its position as new information becomes available.
Additional information
Transmission
Epidemiologic and genomic analysis suggests a single spillover event from wild birds with subsequent cow-to-cow transmission. Evidence suggests cow-to-cow transmission may occur through milk via fomites. However, other means of transmission are being considered. Non-clinical animals can also shed the virus in their milk, indicating that testing lactating animals' pre-movement is valuable in reducing between-farm disease transmission risk. Many herds infected with HPAI have a history of introduction of new animals from an affected area or herd.
The United States Department of Agriculture (USDA) reports lateral transmission from affected dairy herds to nearby poultry flocks based on epidemiologic and genomic analysis. Transmission is suspected to be via fomites (humans and/or equipment).
Personal safety
Avian influenza viruses, such as the highly pathogenic A(H5N1) currently circulating in wild birds in Canada, can, on rare occasions, cause disease in humans. Canada has never reported a locally acquired case of HPAI A(H5N1) in a person and the risk of avian influenza transmission to humans remains low.
People in contact with animals, including cattle and animal products, suspected or confirmed to be infected with avian influenza, or those exposed to highly contaminated environments, should take extra precautions to protect themselves by wearing personal protective equipment (PPE). This includes face masks, non-ventilated goggles, gloves, coveralls and boots. Boots, coveralls and other reusable PPE should be fully cleaned and disinfected between farms. Disposable gloves and face masks should be discarded on farm in a sealed bag.
The Public Health Agency of Canada's (PHAC) website has more information for people in contact with potentially infected animals or heavily contaminated environments: Infection prevention recommendations for individuals involved in animal outbreak situations.
Additionally, PHAC has partnered with the Canadian Centre for Occupational Health and Safety to provide advice on how to protect against avian influenza at work. For more information, please visit How to protect yourself from avian influenza A(H5N1) at work.
Additional information on avian influenza A (H5N1) in people is available from the Public Health Agency of Canada.
Biosecurity
To prevent exposure and spread of HPAI in cattle, producers and veterinarians should continue to follow good biosecurity measures, such as those outlined in the National Biosecurity Standards (Animal biosecurity). Dairy producers are required to adhere to biosecurity plans outlined in Dairy Farmers of Canada's proAction program.
In addition to emphasizing the value of good routine biosecurity practices to their clients, veterinarians are encouraged to highlight the following:
- to prevent HPAI introduction onto a farm:
- avoid bringing new animals onto the farm
- if new animals must be added to a herd, or if animals have had contact with animals from other herds (for example show or sale yard), isolate and monitor for 30 days
- completely clean and disinfect the livestock trailer if moving cattle from other herds
- minimize and restrict wildlife access to cattle and their environment including feed and water sources
- in addition to the list above, for herds where HPAI is suspected in cattle:
- take personal safety precautions as outlined above
- re-enforce good milking practices, such as equipment disinfection and milking sick or new cattle separately or last
- isolate sick cattle from the herd
- avoid housing multiple species together; where other species are kept on the same premises, particularly birds or pigs, emphasize the need for heightened biosecurity measures between different species on the farm
- limit animal movements as much as possible within and off the farm
- do not consume raw milk or feed it to other animals on farm
For further information on biosecurity practices to keep livestock safe, contact your provincial or territorial Chief Veterinary Officer.
Appendix – Provincial and territorial reporting requirements and contact information
Provinces and territories where HPAI in cattle is a reporting requirement
British Columbia
BC Chief Veterinary Officer
(604) 556-3003
Chief.Veterinarian@gov.bc.ca
Saskatchewan
Dr. Wendy Wilkins
(306) 798-0253
wendy.wilkins@gov.sk.ca
Manitoba
Manitoba Chief Veterinary Officer
(431) 323-5638
cvo-eoc@gov.mb.ca
Ontario
Dr. Greg Worley
(519) 826-3577
Greg.Worley@ontario.ca
Prince Edward Island
Dr. Jill Wood
(902) 370-4923
jswood@gov.pe.ca
Quebec
1 844 ANIMAUX (1 844 264-6289)
animaux@mapaq.gouv.qc.ca
Newfoundland and Labrador
Dr. Beverly Dawe
(709) 637-2042
beverlydawe@gov.nl.ca
Yukon
Dr. Mary Vanderkop
(867) 456-5582
mary.vanderkop@yukon.ca
Provinces and territories where HPAI in cattle is not a reporting requirement
Alberta
Alberta Chief Veterinary Officer
(780) 427-3448
Chief.Prov.Vet@gov.ab.ca
New Brunswick
Dr. Nicole Wanamaker
(506) 433-0493
nicole.wanamaker@gnb.ca
Nova Scotia
Dr. Wilma Schenkels
(902) 890-2941
Dr.Wilma.Schenkels@novascotia.ca
Northwest Territories
Dr. Naima Jutha
(867) 767-9237 ext. 53232
Naima_Jutha@gov.nt.ca
NunavutN/A
Related links
- Canadian Animal Health Surveillance System – Dairy
- Animal Health Canada Update – US Detections of H5N1 in Dairy Cattle
- Canadian Association of Bovine Practitioners
- World Organisation for Animal Health
- Canadian Wildlife Health Cooperative
- Highly pathogenic avian influenza (HPAI) in livestock
- Public Health Agency of Canada – Guidance on human health issues related to avian influenza in Canada (HHAI)
- United States Department of Agriculture – Highly Pathogenic Avian Influenza (HPAI) Detections in Livestock
