Several laboratory tests are available to detect outbreaks of canine influenza.

CIV infection should be suspected in dogs with respiratory signs.

Ancillary Diagnostic Work-up for Individual Dogs

The diagnostic work-up for individual dogs with suspected or confirmed CIV infection can provide important information to assist veterinarians in making treatment decisions.

• A complete blood count (CBC) with differential, serum biochemistry profile, urinalysis, thoracic radiographs, and cultures can all provide helpful information. The CBC may be normal, or show mild leukopenia consistent with viral infection; however, leukocytosis (neutrophilia) with or without a left shift may indicate that the dog is developing pneumonia.
• Thoracic radiograph findings may range from mild bronchointerstitial infiltrates to consolidation of all lung lobes.
• Secondary bacterial infection may be identified by cultures performed on nasal swabs from dogs with purulent nasal discharge, or on transtracheal and endotracheal washes of dogs with pneumonia. Potential pathogens include a variety of gram-positive and gram-negative bacteria, including Staphylococcus spp., hemolytic and nonhemolytic Streptococcus spp., Pasteurella multocida, Klebsiella pneumoniae, Escherichia coli, and Mycoplasma spp.
• Antibiotic therapy can be targeted based on culture and sensitivity results.²