Читать книгу Infectious Disease Management in Animal Shelters - Группа авторов - Страница 151

As with most viral diseases, it can be difficult to determine the role of a virus in a clinical event. Reliable diagnosis of many viral diseases by serology requires both acute and convalescent serum samples. Virus detection by PCR in respiratory secretions from acutely ill or recently exposed animals is possible, but false negatives are not uncommon. The Becton‐Dickinson Flu‐A ELISA test may also be used on nasal secretions from acutely affected animals. While the mortality rate of canine influenza is fairly low (5–8%), if an animal does die or is euthanized with respiratory disease, the most accurate test for the virus is a PCR test of respiratory tissue. This, combined with histological features of viral‐induced pneumonia, would be the “gold‐standard” for the presence, and effect, of the virus. In several identified cases of CIV, there was a concurrent and severe bacterial pneumonia, so samples for culture and antibiotic sensitivity should be concurrently submitted.

Gross findings: Influenza virus will be hematogenously disseminated (affect all lobes). The lungs can be hemorrhagic or consolidated (interstitial pneumonia). Again, lungs are among the most difficult of organs in which to detect gross changes; histological analysis is of paramount importance in evaluating the sequelae of the virus and/or co‐infections in the lungs. The tissue collection protocol that was elaborated for respiratory disease sample collection should be followed.

PCR: Fresh, or fresh frozen respiratory tissue is always best, but RNA extracted from paraffin‐embedded tissues has been used to detect the virus. Laboratories that offer this type of testing are limited but will accept samples by courier. Some specific instructions are listed below.

US:

https://www.idexx.com/en/veterinary/reference‐laboratories/canine‐feline‐influenza

California:

https://pcrlab.vetmed.ucdavis.edu/veterinary‐diagnostics

New York:

https://ahdc‐portal.vet.cornell.edu/#!/test_fee/search

Wisconsin:

https://www.wvdl.wisc.edu/index.php/canine‐influenza‐information‐for‐veterinarians