H1N1 Influenza Virus Infection—Colorado

8-year-old female domestic shorthair cat

History and Clinical Presentation
An 8-year-old female domestic shorthair cat was taken to a shelter after her owner passed away. The cat was adopted into a new home after 24 hours. The cat began to show respiratory signs in the new owner’s home after five days and was taken to the Colorado Avenue Vet Hospital in Colorado Springs. On presentation, the cat was sneezing and had a clear oculonasal discharge.


Diagnostic Testing
The veterinarian recommended performing the Feline Upper Respiratory Disease (FURD) RealPCR™ Panel, available through IDEXX Reference Laboratories. This diagnostic panel includes real-time PCR tests for the five most common feline respiratory pathogens, as well as the new H1N1 Influenza Virus RealPCR™ PCR Test. The owner agreed to have the panel performed. A conjunctival and a deep pharyngeal swab were collected and submitted for the FURD DNA test on Monday, January 11, 2010.


The cat was treated symptomatically with broad spectrum antibiotics, fluids and L-lysine for feline herpesvirus type 1 (FHV-1) infection and was released the same day.


Laboratory Results
The results of the FURD RealPCR panel were positive for H1N1 influenza virus and for FHV-1. The influenza virus result was subsequently confirmed at the California Animal Health and Food Safety (CAHFS) Laboratory System at the University of California, Davis, to be the 2009 H1N1 influenza virus currently circulating in the human population. The results were reported to Colorado Avenue Veterinary Hospital on Tuesday, January 12, 2010.


A diagnosis of feline upper respiratory disease secondary to coinfection with FHV-1 and H1N1 influenza virus was made. FHV-1 is a common cause of upper respiratory disease in cats. H1N1 influenza virus infection has been confirmed in a number of cats since the fall of 2009. However, in most reported cases the cats have been exposed to a family member with a confirmed case of H1N1 influenza virus. There was no known exposure of this cat at either the shelter or in its new home to a person with H1N1 influenza virus or flu-like symptoms. The infection was only detected because the H1N1 influenza virus test is a component of the FURD RealPCR panel.


The cat is reported to be doing well at home and is scheduled for a recheck in seven days. The shelter has also been notified of the results.


For consultation on a possible H1N1 influenza virus case, please contact an IDEXX internal medicine specialist at 1-888-433-9987, option 4, option 2.