Influenza continues to affect dogs

An outbreak of canine influenza in dogs in a Chicago veterinary clinic serves as a reminder that the disease continues to spread throughout the United States.

The outbreak marks the first time the disease was confirmed in dogs in Illinois. Approximately 60 dogs were infected at the clinic in June. Five of the dogs developed pneumonia requiring hospitalization, but there were no fatalities.

Canine influenza was first identified in racing Greyhounds in 2004 at a track in Florida. Then in 2005, the virus was found in dogs in shelters, boarding facilities, and veterinary clinics in several areas of the state.

The number of dogs infected with canine influenza has increased in New Jersey. Several dogs were infected in one kennel in May, resulting in one fatality from pneumonia, and more than 100 dogs were infected in a boarding facility in July, according to Dr. Cynda Crawford, a veterinary immunologist at the University of Florida College of Veterinary Medicine.

Dr. Crawford was among the group of researchers who first identified the virus. She is currently studying canine influenza in dogs in shelters as part of a Morris Animal Foundation study that is partially funded by the American Veterinary Medical Foundation.

Since the 2005 outbreak, Dr. Crawford said, canine influenza has been confirmed in Greyhounds and other dogs in 31 states and the District of Columbia. The disease is endemic in northern Colorado, southern Florida, New York City, Pennsylvania, and southern Wyoming.

At this time, no vaccine is available to protect against canine influenza. The AVMA Executive Board approved a policy in November 2006 that states: "The AVMA believes there is urgent need for an effective canine influenza virus vaccine to improve the health and welfare of animals and reduce the financial impacts of canine influenza."

At the AVMA House of Delegates' regular session this July in New Orleans, a resolution was disapproved that called for the AVMA to actively promote evidence-based research on canine influenza virus and its potential effects on animal and human health (see page 690). One of several reasons for the disapproval was that personnel at the Center for Veterinary Biologics of the Department of Agriculture's Animal and Plant Health Inspection Service reported concerns about lack of evidence that canine influenza virus is causing disease in dogs.

For more information on canine influenza, view the AVMA backgrounder, answers to frequently asked questions, and interim guidelines by clicking here.