OIE: Highly pathogenic influenza A viruses (infection with H5N1) (non-poultry including wild birds), USA

Summary
Report type: immediate notification
Started: 19 Apr 2022
Confirmed: 5 May 2022
Reported: 10 May 2022
Reason for notification: unusual host species
Causal agent: highly pathogenic avian influenza virus
Serotype: H5N1
Nature of diagnosis: clinical, laboratory

Outbreak location 1: Rock County, Wisconsin
Started: 19 Apr 2022
Epidemiological unit: other
Total animals affected:
Species / Susceptible / Cases / Deaths / Killed and disposed of /
Slaughtered or killed for commercial use / Vaccinated
Red fox (_Vulpes vulpes_): Canidae-Carnivora / - / - / 1 / - / - / -
Affected population: captive wild red fox kit (_Vulpes vulpes_) at a
rehabilitation facility.

Outbreak location 2: Waushara County, Wisconsin
Started: 24 Apr 2022
Epidemiological unit: other
Total animals affected:
Species / Susceptible / Cases / Deaths / Killed and disposed of /
Slaughtered or killed for commercial use / Vaccinated
Red fox (_Vulpes vulpes_): Canidae-Carnivora / - / - / 1 / - / - / -
Affected population: captive wild red fox kit (_Vulpes vulpes_) at a
rehabilitation facility.

Epidemiology
Source of the outbreak(s) or origin of infection: contact with wild
species, unknown or inconclusive.

Epidemiological comments: highly pathogenic avian influenza (HPAI)
H5N1, Eurasian lineage goose/Guangdong clade 2.3.4.4b was confirmed in
2 wild red fox kits from Rock and Waushara Counties (in Wisconsin).
The animals were found displaying neurological signs and taken to
rehabilitation facilities, where they since have died. Full genome
sequencing is pending. Testing is also underway for several additional
fox kits found at the time of the 2 confirmed cases. This is the 1st
report of HPAI in mammals in the United States.

Wild control measures applied: surveillance within the restricted
zone, official disposal of carcasses, by-products and waste,
disinfection.

Diagnostic test results
Laboratory name and type: National Veterinary Services Laboratories
(NVSL), Ames, Iowa (National Laboratory)
Species / Test / Test date / Result
Red fox / Real-time reverse transcription polymerase chain reaction
(rRT-PCR) / 5 May 2022 / positive