Thursday, July 19, 2012

Canine influenza virus (CIV)

This article was prepared by Pet Sitters, Intl using published material from

MERCK Animal Health.  Your vet. may refer to the vaccine as H3N8.  If you

are not already vaccinating your dog against this virus, be sure to discuss

with your vet.  Unless your vet. advises against it for particular health issues

related to your dog, I recommend that your dog be vaccinated and continue

to receive the yearly boosters to protect against this highly contagious illness.


Canine influenza virus (CIV) spreads fast when

dogs get together

You may have heard: dogs can get the flu, too. It’s a relatively recent development. The virus that causes flu in dogs, canine influenza virus H3N8, was only first identified in January 2004. Dog flu cases have now been reported in 39 states.

One of the factors that makes CIV such a concern for anyone who owns or works with dogs is that the virus can spread quickly and easily.1 Because most dogs have no natural immunity against CIV, virtually all dogs exposed to the virus become infected.2,3 CIV can be spread through direct dog-to-dog contact and through airborne particles released when an infected dog coughs or sneezes.

Recognize the signs of dog flu

Like human flu, canine influenza causes respiratory infection and may lead to more serious conditions like pneumonia. The most common sign of dog flu is a soft, wet cough that may last for up to 3 to 4 weeks. Other signs include fever, nasal discharge, lethargy, and loss of appetite. If you notice any of these signs,  have your dog examined by a veterinarian.

However, recognizing the signs of dog flu is not enough to prevent spreading the disease. Here are 3 reasons why:

 1.      Some infected dogs do not appear to be sick. About 20% of infected dogs show no signs of disease but can still spread CIV to other dogs.3

2.      If you’ve spotted signs of flu, it’s probably too late. By the time a CIV-infected dog shows signs of illness, the dog is likely to have stopped spreading the virus. In other words, the damage has already been done. You may have already unintentionally spread the virus to other dogs. And remember, just because you see clinical signs of flu doesn’t mean it is flu.

3.      Dog flu cannot be diagnosed by clinical signs alone.4The signs of dog flu are very similar to those of other respiratory infections, such as Bordetella. As a result, dog flu is often mistaken for other conditions.

The first CIV vaccine approved in 2009, Nobivac® Canine Flu H3N8 from Merck Animal Health, has been shown to reduce the spread of disease among dogs.5 This can help reduce the likelihood of dog flu outbreaks. As in human flu vaccination, vaccination in dogs is not 100% effective in preventing flu but can help reduce its impact.

Not only does CIV vaccination offer protection for individual dogs, it also promotes overall immunity for all dogs within a given population. This “community immunity” takes effect when a sufficient number of dogs are vaccinated to limit the spread of the virus.6

For more information, go to to find out more about CIV and theNobivac Canine Flu H3N8 vaccine.

1. Canine influenza backgrounder. AVMA Website. Available at: Updated September 9, 2009. Accessed May 4, 2012.

2. Jirjis FF, Deshpande MS, Tubbs AL, Jayappa H, Lakshmanan N, Wasmoen TL. Transmission of canine influenza virus (H3N8) among susceptible dogs. Vet Microbiol. 2010;144(3–4):303–309.

3. Crawford C, Spindel M. Canine influenza. In: Miller L, Hurley K, eds. Infectious Disease Management in Animal Shelters. Ames,IA: Wiley-Blackwell; 2009:173–180.

4. Anderson TC, Crawford PC. Diagnosing H3N8 CIV infection.Clinician’s Brief. 2011;9(10):69­–72.

5. Deshpande MS, Jirjis FF, Tubbs A, et al. Evaluation of the efficacy of a canine influenza virus (H3N8) vaccine in dogs following experimental challenge. Vet Ther. 2009;10(3):103–112.

6. National Institute of Allergy and Infectious Diseases.Community immunity ("herd" immunity). Available at: Accessed May 4, 2012.

No comments:

Post a Comment