Acute bronchointerstitial pneumonia in two indoor cats exposed to the H1N1 influenza virus.
OBJECTIVE
To describe 2 cases of acute bronchointerstitial pneumonia in indoor domestic cats infected by anthroponotic transmission of pandemic 2009 influenza A H1N1 virus from their owners.


METHODS
Two indoor domestic shorthair cats from the same household were evaluated for acute onset of respiratory distress. The owners had been recovering from flu-like illness at the time of presentation. Venous blood gas showed increased pvCO2 while thoracic radiographs revealed severe bronchointerstitial to alveolar patterns in both cats. The cats were treated with oxygen supplementation, antimicrobials, analgesics, diuretics, corticosteroids, bronchodilators, mechanical ventilation (1 cat), and supportive care. Despite initial improvement in the clinical condition of each cat, respiratory function deteriorated and ultimately both cats were euthanized. Gross and histopathologic examination confirmed diffuse, severe bronchointerstitial pneumonia. Pandemic 2009 influenza A H1N1 viral testing by real time PCR was positive in 1 cat.


CONCLUSIONS
These cases provide further evidence that domestic felids are susceptible to pandemic 2009 influenza A H1N1 virus, and the literature is briefly reviewed for treatment recommendations. H1N1 should be considered in the differential diagnosis for domestic cats presenting with peracute to acute onset of respiratory distress in the right context. While human-to-cat transmission of H1N1 seems probable in several reported cases, cat-to-human transmission has not been identified.
Animal Emergency Center and Specialty Services, 2100 W Silver Spring Dr, Glendale, WI, 53209.
Armi M
AM
Pigott
Carol E
CE
Haak
Melanie A
MA
Breshears
Andrew K J
AK
Linklater
D000818:Animals; D002371:Cat Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000821:virology; D002415:Cats; D003937:Diagnosis, Differential; D005260:Female; D006799:Housing, Animal; D053118:Influenza A Virus, H1N1 Subtype; D008297:Male; D009976:Orthomyxoviridae Infections / Q000175:diagnosis / Q000662:veterinary*; D011024:Pneumonia, Viral / Q000175:diagnosis / Q000662:veterinary*; D013902:Radiography, Thoracic / Q000662:veterinary; D012121:Respiration, Artificial / Q000662:veterinary
anthroponotic; feline; flu; respiratory failure