Credit Wikipedia
#16,996
While marine mammals (mostly seals and very rarely whales) are known to be susceptible to avian flu, just over a week ago, in Sweden: First Known Infection of A Porpoise With Avian H5N1, researchers from Sweden's Statens Veterinärmedicinska Anstalt (National Veterinary Institute) announced the first finding of HPAI H5N1 in a cetacean.
The first detection isn't necessarily the first occurrence, as many creatures die (or recover) unnoticed in the wild, and it takes a certain amount of luck and perseverance to find a specimen that can be examined and tested.
So, when we see sporadic reports of a HPAI H5N1 in a bear, or in foxes, or a polecat we can assume there are other spillovers into mammals we are not aware of.
Not surprisingly, yesterday researchers at the University of Florida announced a similar finding in a bottlenose dolphin, collected last March in Dixie county. Click the link to read the news release in full, I'll have more when you return.
A first: Avian influenza detected in American dolphin
Published: Sep 7, 2022 By: Sarah Carey Category: University of Florida, UF Health, College of Veterinary Medicine
The young male dolphin was recovered in March at Horseshoe Beach by the University of Florida’s marine animal rescue team. A collaboration between UF College of Veterinary Medicine researchers and state and federal laboratories identified the unexpected infection with HPAIV, commonly known as bird flu. The virus recovered from the dolphin belonged to clade 2.3.4.4b of the Eurasian H5 viral lineage.
Wild birds have spread H5 clade 2.3.4.4b HPAIV widely in North America and Europe this year. The virus primarily affects wild birds and domesticated poultry but only rarely infects people. Researchers suspect the dolphin likely got infected by interacting with a wild bird killed by HPAIV.“While obviously the presence of HPAIV is a concern, the key takeaway for us is that additional caution should be taken by those handling or encountering wild dolphins during rescue events or while performing necropsies,” said Mike Walsh, D.V.M., a clinical associate professor with UF’s College of Veterinary Medicine who leads the animal rescue team and performed the dolphin’s necropsy with others.
There has been only one report of H5 clade 2.3.4.4b in people in 2022.
Richard Webby, Ph.D., directs the World Health Organization Collaborating Center for Studies on the Ecology of Influenza in Animals and Birds at St. Jude Children’s Research Hospital. The WHO Center at St. Jude, which analyzes animal flu viruses and their potential risk to human health, will analyze the dolphin tissue samples supplied by the UF team.
This is just the latest in an impressive string of `firsts' racked up by HPAI H5N1 over the past 12 months. Others include:
- The first human infections (In the U.S. and in England)
- Its designation as a zoonotic virus by the CDC and the ECDC
- Its crossing of both the Atlantic and Pacific oceans to North America via migratory birds
- Its first detection in the Arctic (see HPAI Detected In Arctic (Svalbard) For the First Time)
- Its unusual persistence over the summer months (see Ain't No Cure For the Summer Bird Flu)
Over the first 3 days of September - a time when HPAI activity ought to be at its nadir - the USDA reported 9 outbreaks, including the biggest in the U.S. during this epizootic so far; 3 million laying hens in Ohio (See Department of Agriculture report).
While previous incarnations of HPAI H5N1 have loomed large before - only to recede - past performance is no guarantee of future results.
Clade 2.3.4.4b continues to evolve, and has become more widespread - and better adapted to year-round persistence (see Study: Global Dissemination of Avian H5N1 Clade 2.3.4.4b Viruses and Biologic Analysis Of Chinese Variants) - making it a more pervasive threat than we've seen previously.
How this plays out is anyone's guess. But we need to be prepared to deal with new challenges ahead.
