Page 962 - Clinical Small Animal Internal Medicine

900 Section 9 Infectious Disease

Diagnosis Public Health Implications
VetBooks.ir Diagnosis of WNV in the live patient requires paired As WNV is a biologic safety level (BSL) 3 pathogen, any-

acute and convalescent serum samples for neutralizing
apparel and, if possible, work in a laminar flow hood. In
antibody. Due to the widespread seropositivity, single one performing a necropsy should wear protective
serum samples are nondiagnostic. If a necropsy is per- most cases, it would be preferable to send the body to a
formed (with appropriate biocontainment gear or facili- diagnostic laboratory with appropriate facilities for test-
ties), the following tissues should be collected and ing. There is no documented evidence of dog‐ or cat‐to‐
submitted chilled, not frozen, for WNV polymerase person transmission of WNV. WNV has not been
chain reaction (PCR), immunohistochemistry and/or detected in the saliva of dogs so dog bites would not
virus isolation: heart, kidney, brain/brainstem, a section appear to be a risk factor for human infection. Neither
of spinal cord. dogs or cats are considered epidemiologically important
amplifying hosts, although peak viremias in cats may be
high enough to infect mosquitoes at low efficiency.
Therapy Suspect cases should be reported to your state veteri-
narian, state diagnostic laboratory or reference labora-
There is no specific therapy for WNV infection. tory. Positive cases should be promptly reported to your
Supportive care should be provided. An experimental local Department of Health. Clients may ask about
recombinant canarypox vectored WNV vaccine pro- methods of mosquito protection in dogs and cats. It is
tected dogs and cats against mosquito challenge but is important to emphasize that DEET‐containing products
not commercially available. are not approved for use in pets and should not be used.
The same holds for citrus‐based oils that have been
found to cause contact dermatitis. Owners should be
Prognosis advised to eliminate mosquito habitat and avoid outdoor
exposure of pets during peak mosquito feeding activity
Full recovery is likely. (early morning and dusk).

Further Reading

Austgen LE, Bowen RA, Bunning ML, Davis BS, Mitchell infection in humans. J Am Vet Med Assoc 2005; 226(8):
CJ, Chang G‐JJ. Experimental infection of dogs and cats 1349–53.
with West Nile virus. Emerg Infect Dis 2004; 10(1): Lichtensteiger CA, Heinz‐Taheny K, Osborne TS, Novak
82–88. RJ, Lewis BA, Firth ML. West Nile virus encephalitis and
Karaca K, Bowen R, Austgen LE, et al. Recombinant myocarditis in wolf and dog. Emerg Infect Dis 2003;
canarypox vectored West Nile virus (WNV) vaccine 9(10): 1303–6.
protects dogs and cats against mosquito challenge. www.cdc.gov/ncidod/dvbid/westnile/birds&mammals.htm
Vaccine 2005; 23: 3808–13. (accessed June 24, 2019).
Kile JC, Panella NA, Komar N, et al. Serologic survey of www.oie.int/international‐standard‐setting/terrestrial‐
cats and dogs during an epidemic of West Nile virus manual (accessed June 24, 2019).