ProMed reported on a case of highly pathogenic avian influenza strain H5N1 apparently responsible for meningitis in a stranded porpoise near Kampersvik in Vastra Gotaland during late June.

Postmortem examination yielded H5N1 from numerous organs with meningitis as the significant lesion presumably leading to stranding and death.

Seals have been infected with H5N1 in Northern Europe and along the New England coast of the U.S. and also the Maritime provinces of Canada.  In addition, other mammals shown to be susceptible to H5N1 include foxes in both the EU and the U.S. and skunks and raccoons that may disseminate virus during transitory infection, even without serving as long-term reservoirs.

Wildlife specialists in Sweden presume that the porpoise was infected through contact with sea birds shedding H5N1 strain AI virus.

A similar case was docmented in Florida with isolation of H5N1 HPAI virus with a Eurasian genome  from a dead porpoise