A 13-year-old neutered male, mixed-breed dog in Bedford Hills, N.Y., has tested positive for the 2009 novel H1N1 influenza virus, according to IDEXX Laboratories, which confirmed the infection in December.
This is the first time a dog in the United States has been confirmed to be infected with the H1N1 flu virus. Reports from China indicated that a small number of dogs had contracted the virus.
Test results for samples submitted to IDEXX were negative for the H3N8 canine influenza virus but positive for the 2009 H1N1 influenza virus. Test results were confirmed by the Iowa State Laboratory.
Also in December, the U.S. Department of Agriculture announced that a government study provides additional confirmation that meat and tissue from pigs exposed to two strains of the 2009 novel H1N1 virus do not contain the virus.
Scientists with the USDA Agricultural Research Service inoculated a group of 30 five-week-old pigs with the virus to determine the pigs' susceptibility to H1N1, the USDA stated. Five pigs that were not inoculated with the virus served as a control group. The pigs were observed daily for clinical signs of illness and then were euthanized at three, five, or seven days after inoculation.
Researchers tested tissue samples of the pigs' lungs, liver, muscle, spleen, and other vital organs, using the most sensitive tools available to detect the presence of live virus and nucleic acids from the virus, according to the USDA.
Although the inoculated animals developed signs of upper respiratory tract disease consistent with influenza, there was no evidence that the virus had spread to any other parts of the body, the USDA said.
"This research provides additional reassurance for consumers about the safety of pork," said ARS Administrator Edward B. Knipling, PhD.
The list of nonhuman animal species susceptible to the H1N1 virus continues to grow. In addition to dogs and pigs, cats, ferrets, turkeys, and a captive cheetah have tested positive for flu virus.
The N.Y. dog appears to have been infected by its owner and recovered after treatment by a veterinarian.
In a press release, IDEXX explained that the dog was taken to the Katonah Bedford Veterinary Center in Bedford Hills, N.Y., Dec. 13. Two days prior, the dog was examined by its regular veterinarian after several days of illness. The patient was initially treated with antimicrobials and anti-inflammatory drugs, with no response.
On examination at the Katonah Bedford Veterinary Center, the dog had a dry cough, was reportedly lethargic and not eating, and was febrile, with a rectal temperature of 103.6°F, IDEXX stated. The owner reported that he had tested positive earlier in the week for the H1N1 flu virus.
Thoracic radiography of the dog revealed evidence of pneumonia. The dog was treated with fluids IV, antimicrobials, nebulization, and other supportive care, and was discharged from the hospital after 48 hours of care, according to IDEXX.
The AVMA is actively tracking all instances of H1N1 in animals and posting updates on its Web site at www.avma.org/public_health/influenza/new_virus.