The potentially deadly avian influenza has been detected in seals in Washington state, and while marine mammal experts in British Columbia are on alert they say there’s no need to panic.
“Definitely not panic mode, but certainly very worthwhile monitoring,” said Martin Haulena, head veterinarian and director of animal health and research at the Vancouver Aquarium Marine Mammal Rescue Centre (VAMMR).
Three seals south of Vancouver Island have tested positive, according to officials.
On Friday, the National Marine Fisheries Service (NOAA Fisheries) said the adult harbour seals had the highly pathogenic avian flu. They were found near Fort Flagler State Park, on Marrowstone Island in Puget Sound, on Aug. 18 and 25, and at the time NOAA said no seal pups had tested positive.
“As far as we know, in North American coasts, these are the first confirmed cases of avian influenza, or highly pathogenic avian influenza, in seals in Washington state,” said Haulena in an interview with CHEK News Monday.
It’s possible they entered Canadian waters because “our seals definitely cross the border with some regularity,” he said.
“Harbour seals do have sort of a home range, but that home range can be quite extensive. It is possible that those seals, that were positive, go back and forth between the border.”
Avian flu can have grave impacts and is often associated with mortality, “so that means death,” noted Haulena. “For both seals and sea lions, it can cause death, and it’s certainly a concern that seals here have started becoming positive.”
Ongoing outbreak in seabirds
NOAA says the positive tests in seals follow an outbreak in seabirds on Rat and Marrowstone islands that has killed about 1,700 terns and gulls since mid-summer.
“There have been a few big outbreaks recently,” said Haulena, referring to an outbreak in Peru that killed thousands of sea lions this spring.
“The discovery of HPAI H5N1 (avian flu) in seals brings to light the potential for cross-species transmission and highlights the complexity of managing infectious diseases in wildlife populations,” said Kristin Wilkinson, NOAA’s regional stranding and entanglement coordinator, in a release Friday.
Seals often share spaces with seabirds, and Haulena says they likely caught the virus after coming into contact with infected birds, including bird feces or nasal discharge.
“Close contact with any kind, really,” said Haulena.
Yet he reiterates, “I don’t think it’s a cause for panic, necessarily, right now,” adding, “We definitely have avian influenza in wild birds along the West Coast, that’s definitely been reported. So it’s likely the virus has been here before, even though we haven’t recognized it as a cause of mortality in seals yet.”
According to Haulena, animals with avian flu can suffer from respiratory or neurologic problems or just look lethargic. Sometimes, seals are asymptomatic, so they don’t show signs they’re sick.
“That is the nature of disease,” he said.
But staff at VAMMR treat animals from across B.C., including seals, so they’re able to take blood or naval samples and test for the virus.
“The animals in our facility are really a good source of information,” said Haulena, “So we can get an idea of how extensive the spread might be.”
He encourages people who see an animal in distress to reach out to the Department of Fisheries and Oceans (DFO) and VAMMR and to not handle it themselves.
“It is potentially a ‘zoonotic’ disease,” he added. “We don’t know for sure that seals can pass it to humans or other seals, but definitely something to be cautious of.”
NOAA has more safety tips here.