Canine Influenza Vaccine H3N8

While the swine-flu pandemic and the supply, demand and advisability of an associated vaccine have captured the media’s attention for weeks, an influenza and vaccine have quietly made their way into the forefront of veterinary medicine, too.

Canine Influenza Vaccine H3N8, produced by Intervet Schering-Plough Animal Health, was introduced this summer at the American Veterinary Medical Association in Seattle.

“Canine influenza is a highly contagious respiratory infection that has a significant impact on dogs housed in shelters, kennels and communal facilities,” says Dr. Cynda Crawford, University of Florida clinical assistant professor of shelter medicine. “The availability of a vaccine can help prevent the medical, financial and emotional costs associated with this new virus.” Unlike human influenza, canine influenza is not a “seasonal” infection, it occurs year round.

The vaccine, according to Intervet Schering-Plough Animal Health scientists, has been shown to decrease the signs, severity and spread of CIV infection which masquerades as kennel cough but is a different pathogen. Hence, if your dog is immunized for Bordetella it is not protected for Canine Influenza Virus.

The CIV vaccine reduces the duration and intensity of coughing and protects against the formation and severity of lung lesions. The product was tested in a 746-dog field study involving 30 breeds ages 6 weeks to 10 years. It is recommended for healthy dogs 6 weeks and older and administered subcutaneously in two doses two to four weeks apart. Annual booster shots are recommended thereafter.

The virus can be spread by direct contact with respiratory secretions from infected dogs via a cough or a sneeze or by contact with contaminated items such as dog bowls and clothing or by individuals moving between infected and uninfected dogs.

Chances are you probably won’t realize your dog has contracted the disease until it begins coughing, says Terri Wasmoen, an immunologist and senior director of Biological Research for Intervet/Schering-Plough Animal Health. The coughing, however, doesn’t occur until several days after the dog has contracted Canine Influenza Virus, leaving it vulnerable to pneumonia. Other symptoms are weepy eyes and runny noses and fever.

Infected dogs shed virus in respiratory secretions for seven to 10 days, according to Wasmoen, at which time they are contagious to other dogs. After the virus has run its course, the dog is no longer contagious, but she recommends isolating it from healthy dogs for two weeks.

By the time the owner gets the dog to the veterinarian, the virus is pretty well advanced, adds Dr. Michael Moyer, Rosenthal Director of Shelter Medicine at the University of Pennsylvania School of Veterinary Medicine, Philadelphia. He cited hot spots as New York City, Philadelphia, New Jersey, Colorado, Delaware. Denver and parts of South Florida. It has been seen in 30 states and the District of Columbia.

The vaccine, says Dr. Jim Evermann, Washington State University College of Veterinary Medicine professor of infectious disease, is “non-core” in the Pacific Northwest, meaning it is not routinely recommended unless there are risks associated with infection, i.e. association with greyhounds, race tracks, etc. Dog owners traveling with their dogs to shows in any of the hot spot areas should confer with their veterinarian to decide if they want to vaccinate. The infection rate and disease potential with canine influenza, adds Evermann, is much lower than canine distemper, canine parvovirus and canine adenovirus, all of which are core vaccines for all dogs.

Moyer was quick to add that the virus does not affect people or cats, rabbits, ferrets and birds. Canine Influenza Virus had its origin in horses more than 40 years ago and was first identified in dogs at greyhound tracks in Florida in 2004 and later seen with respiratory outbreaks in racing greyhounds in five states from 2004-2006.

It is estimated that 5 to 8 percent of the dogs infected with the disease will die. About 20 percent will show no clinical signs while 10-20 percent may progress to a more severe form of the disease, namely pneumonia.