UW Shelter Medicine assists with cases of influenza in shelter dogs

Nine dogs in two Oakland, California, animal shelters have tested positive for canine influenza. The Shelter Medicine Program at the University of Wisconsin–Madison School of Veterinary Medicine (SVM) is working closely with the shelters to manage the cases and implement precautionary measures.

Two cases were identified this week when Oakland Animal Services (OAS) sent samples to a private laboratory, IDEXX. The shelter then approached the UW–Madison program for additional assistance. Follow-up testing found additional dogs had also been infected, including two dogs from OAS that had been transferred to East Bay Humane SPCA. Further diagnostic testing is now being conducted with financial support from the family foundation Maddie’s Fund.

“We are working with Oakland Animal Services to respond and manage these cases and to offer additional testing,” says Sandra Newbury, clinical associate professor at the SVM and director of the UW Shelter Medicine Program. “We hope that our support will help to isolate any animals with the virus and prevent its spread.”

Initial IDEXX testing of two dogs from OAS showed the virus to be H3N2 canine influenza. This canine influenza virus strain first appeared in the United States in sick dogs in the Midwest in 2015 and later infected a group of cats in northwest Indiana in 2016. Infection of cats is rare. A second introduction of H3N2 into the San Jose area in California caused illness in pet dogs in the community and also affected shelter animals. The UW–Madison Shelter Medicine Program helped to manage those outbreaks and the Wisconsin Veterinary Diagnostic Laboratory (WVDL) helped identify the virus strain.

The dogs at Oakland Animal Services testing positive for influenza have displayed symptoms such as runny nose, cough and fever. Infected dogs have been isolated and are receiving treatment.

In other efforts to prevent or reduce the virus’s spread, the Oakland shelter is making efforts to divert and limit animal intake and inform adopters about canine influenza’s presence at the shelter and its signs and symptoms. No other cases have been reported outside of the two shelters.

“We will continue to watch carefully for instances of the disease and hope to work with other groups who received dogs from OAS,” Newbury says.

Some dogs affected with canine influenza will show only mild symptoms, while others exhibit more severe signs of illness. The virus has been linked to some deaths in dogs, but most dogs recover with supportive care. An H3N2 vaccine is now available for dogs but provides only partial protection. No vaccine is currently approved or recommended for cats. A veterinarian can recommend whether or not to seek an H3N2 canine influenza vaccine for dogs.

There is no evidence at this time that the H3N2 canine influenza virus strain can infect humans; it is distinctly different from human seasonal influenza H3N2 strains.

Owners whose animals show signs of influenza should contact their veterinarian for instructions. Dogs infected with the virus should be housed separately from other animals and precautions should be taken to prevent spread of the virus on hands and clothing.

Shelters can contact the UW Shelter Medicine Program with testing inquiries or questions regarding influenza in dogs and cats. More details about the program’s partnership to provide diagnostic testing for shelters can be found on its diagnostic testing webpage.