Officials in Cambodia, meanwhile, say 2 recent H5N1 cases do not appear to reflect human-to-human transmission.
Mountain lions, a bobcat, red foxes, black bears, and skunks represent the latest avian flu cases in mammals.
The clade that infected the two Cambodians has been circulating in Southeast Asia for almost a decade, resulting in sporadic human cases.
In a related development, WHO experts recommended a new H5N1 candidate vaccine virus, while noting that current stocks are a good match against circulating viruses.
Infections are rare and can be severe or fatal, but so far scientists don't see genetic changes that pose an increased threat to people.
Argentina, Bolivia, Guatemala, and Uruguay reported their first highly pathogenic H5N1 detections in different wild bird species.
Species include skunk, raccoon, bobcat, red fox, grizzly bear, black bear, tiger, and mountain lion.
In Cuba, the virus struck wild birds that inhabit a zoo in Havana.
The World Organization for Animal Health notes increasing detections in mammals in recent months, which warrants close monitoring.
The UK mammal H5N1 findings include foxes and otters, part of ongoing detections in mammal species alongside outbreaks in poultry and wild birds.
