Here is what the current UC Davis canine vaccination guidelines say about Canine Influenza:
Canine Influenza Virus (CIV)
Canine influenza virus H3N8 emerged in the United States in greyhounds in Florida in 2003. The virus is now enzootic in many dog populations in Colorado, Florida, Pennsylvania, New Jersey and New York. The virus causes upper respiratory signs including a cough, nasal discharge, and a low-grade fever followed by recovery. A small percentage of dogs develop more severe signs in association with hemorrhagic pneumonia. Canine influenza virus H3N2 emerged in 2015 in Illinois and has spread to several other states, including California. Several affected dogs have recently (December 2017/January 2018) been identified in the south bay area in Northern California. Disease caused by CIV H3N2 may be slightly more severe than that caused by CIV H3N8, and the virus has affected more dogs in veterinary hospitals and the community (H3N8 has largely remained confined to shelters). Vaccines for both infections are commercially available, including a combination H3N8/H3N2 vaccine. In Northern California, use of the H3N2 vaccine may be warranted for dogs that contact other dogs, such as those that board. Vaccines may reduce clinical signs and virus shedding in dogs infected by CIV. Vaccination may have the potential to interfere with the results of serological testing, which in non-endemic areas are useful to assist diagnosis.