Posts Tagged ‘dog flu shot’

Canine Influenza outbreak caused by a new strain of virus H3N2 from Asia

Sunday, August 27th, 2017

Midwest Canine Influenza outbreak caused by new strain of virus

April 12, 2015 By Joe Schwartz

ITHACA, N.Y. – The canine influenza outbreak afflicting more than 1,000 dogs in Chicago and other parts of the Midwest is caused by a different strain of the virus than was earlier assumed, according to laboratory scientists at Cornell University and the University of Wisconsin. Researchers at Cornell say results from additional testing indicate that the outbreak is being caused by a virus closely related to Asian strains of influenza A H3N2 viruses, currently in wide circulation in southern Chinese and South Korean dog populations since being identified in 2006. There is no evidence that it can be transmitted to humans.

The outbreak in the Midwest had been attributed to the H3N8 strain of virus, which was identified in the U.S. dog population in 2004 and has been circulating since. The H3N2 virus had not been previously detected in North America. The outbreak in Chicago suggests a recent introduction of the H3N2 virus from Asia.

Testing of clinical samples from the outbreak conducted at The New York State Animal Diagnostic Laboratory at Cornell indicated that the virus was Influenza A. Further testing led researchers to believe a new strain was at fault. Subsequent testing, carried out with the assistance of the Wisconsin Veterinary Diagnostic Laboratory, identified the new subtype as H3N2. The National Veterinary Services Laboratories in Ames, IA is sequencing two isolates from this outbreak, which were isolated at Cornell, to facilitate rapid complete characterization of the viruses.

Both Influenza strains can cause high fever, loss of appetite, coughing, nasal discharge, and lethargy. Symptoms may be more severe in cases caused by the H3N2 virus. Some infected dogs may not show symptoms at all.

H3N2 has caused infection and respiratory illness in cats.

Veterinary professionals are advised that diagnostic testing of samples from sick pets can be done using a broadly targeted Influenza A matrix reverse transciptase-polymerase chain reaction assay (Rt-PCR). The canine-specific Influenza A H3N8 Rt-PCR in use in several laboratories will not detect this virus. Serology is also currently not available as the H3N2 virus is different enough from H3N8 that antibodies may not cross react. However, an H3N2-specific serologic assay is under development and will be available soon.

It is not known if the current vaccine will provide any protection from this new virus. It does protect against H3N8, which is in circulation in some areas. Other preventive advice remains the same: In areas where the viruses are active, avoid places where dogs congregate, such as dog parks and grooming salons.

Owners of symptomatic dogs and cats should consult our office.

It is our pleasure to serve you and your pets. Please do not hesitate to call our offices (708-383-3606) if you have any questions or concerns. Thank you for allowing us to be a part of your veterinary healthcare team.


Canine Influenza Virus Immunization

Wednesday, December 9th, 2015
Vaccine for dog flu

Vaccine for dog flu

Great News – A new targeted H3N2 Canine Influenza virus immunization has been developed and should be available very soon. We are proud to be able to offer the new H3N2 canine specific influenza virus immunization. We are advising all patients going to daycare, boarding facilities of any type, or dog shows to be immunized. We hope to have the vaccine by early December 2015.

FDA Approval

You may hear that the vaccine’s approval is ‘conditional’. This means that because of the importance of this vaccine for pets, the FDA (Food and Drug Administration) is comfortable allowing the vaccine to be administered while they continue their approval process. The drug manufacturer Zoetis, a New Jersey company, is one of the world’s leading animal health care companies ( We are very confident in their work and their products.

We strongly recommend that you get your dog vaccinated. If there are any underlying conditions that might preclude your dog from receiving the vaccine, we will incorporate these in our plan.

History of the H3N2 dog flu

The new canine influenza virus (H3N2) is a bird flu virus that adapted to infect dogs. It has affected over 1,500 dogs in Chicago and other parts of the Midwest in the past 6 months. This virus is different from the H3N2 human seasonal virus. This virus is also different from the previously recognized canine influenza virus in dogs that originated from horses (H3N8) in 2004.

The canine influenza H3N2 virus was first recognized in South Korea in 2007. The virus did spread to China and Thailand. In April of 2015, the virus was first recognized in the United States.

Dog flu symptoms

Both the H3N2 and the H3N8 canine influenza viruses can cause high fever, loss of appetite, coughing, nasal discharge and lethargy. The symptoms are more severe with the H3N2 virus and may result in a secondary pneumonia. The H3N2 influenza virus has also infected and caused respiratory illness in cats.

There is a specific test that has been developed to detect the canine influenza H3N2 virus and should be performed if your pet experiences any of the above symptoms.

Prior vaccine for H3N8

Canine influenzaThere was no evidence that the previous H3N8 immunization had any value in protecting patients against the more serious H3N2 virus. We have been advising not immunizing with the H3N8 vaccine, since these are different viruses and cross protection was not documented. We did not want our clients feeling a sense of false protection.

We spoke to the leading researcher in the H3N2 canine influenza virus at Cornell University in October; he felt that the targeted H3N2 canine influenza virus immunization would be available soon. We have advised minimizing exposure to areas where the virus may be transmitted such as dog shows, daycare facilities and high volume boarding facilities, particularly if positive H3N2 patients have been documented.

Researchers at Cornell University, University of Wisconsin and Kansas State University have been instrumental in the development of the new immunization.


If you have any questions, please call us and speak with one of our doctors.