Canine Influenza Vaccine
Feeding dogs prone to pancreatitis or who can’t tolerate dietary fat.
News item written by Mary Straus, published in the Whole Dog Journal, August 2009.
A new vaccine for canine influenza virus (CIV) developed by Internet/Schering Plough was conditionally approved in May 2009 [Update: full approval granted 6/9/10]. Conditional licenses are granted before much is known about a vaccine’s effectiveness. This is a killed virus vaccine, so it cannot cause disease itself. The makers suggest that two vaccinations are given two to four weeks apart; it can then be given annually. (Whether it needs to be given annually is unclear, since most viral vaccines confer long-term immunity).
Canine influenza was first identified in 2004 in racing greyhounds in Florida. It has now been found in 30 states, though the number of cases is still small. The areas most affected are Florida, New York City’s northern suburbs, Philadelphia, Denver, and a recent outbreak in New Jersey. There is no evidence that it has spread to other countries. Most cases occur where dogs are housed closely together
CIV is a highly infectious respiratory disease that is considered one of many types of kennel cough. Each type of kennel cough is different, so vaccinations for other types will not protect against CIV. It is spread by contact with infected dogs, or with anything that has come in contact with those dogs. The virus can persist for up to a week in the environment, but is deactivated by common disinfectants, such as alcohol and bleach. It is most commonly found in high-traffic facilities, or kennels where many dogs are housed together.
The vaccine may only reduce the duration and severity of the disease rather than giving complete protection, similar to influenza vaccines in other species. It may also reduce shedding of the virus and so make it less contagious. Canine influenza is restricted to dogs and is not contagious to other species.
Virtually all dogs exposed to CIV will be infected, though the severity will vary considerably. Approximately 20 percent of infected dogs may show no signs at all. Symptoms can last up to a month, and may include a low-grade fever, nasal discharge, and a mild, productive cough. In 10 to 20 percent of cases, the virus can lead to high fever and pneumonia, usually caused by secondary bacterial infection. The fatality rate is currently between one and five percent of affected dogs. The virus is not responsive to antibiotics, though they can be helpful for secondary infections.
Should you vaccinate your dog? It depends on your dog's likelihood of exposure and overall health. Because the risk of CIV to most dogs is minimal at this time, few household dogs are likely to benefit from the vaccine. It may be helpful for kennels where large numbers of dogs are housed together, especially in areas where the disease is prevalent. Discuss the potential risks and benefits with your vet.
Update April 2015: An outbreak of canine influenza in the Chicago area is from a new strain of canine influenza. We don't know how effective the vaccine will be against this new strain, but veterinarians are encouraging owners to vaccinate dogs in the area, as even partial immunity might be enough to save a dog's life. More info:
- Canine Flu Update – Vaccines and More (December 2015)
- Midwest Canine Influenza outbreak caused by new strain of virus
- Chicago canine influenza outbreak traced to H3N2 strain
- Does Your Pet Need a “Lifestyle” Vaccine? (Re-Thinking the Dog Flu)
- AVMA Resources:
- Recent reports overstated canine influenza activity(January 2012)
- New worries about canine flu: Should you vaccinate your dog?
- Intervet USA, (908) 298-4000
- Spike in dog-flu reports attracts media attention (12/22/11)
- Canine Influenza Virus
- Confirmed cases by state
- 10 Things to Know About the H3N8 Dog Flu
- New Flu Vaccine Approved – for Dogs
- Canine influenza: Scary news everywhere you look -- but what ' s the real story?
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