Scientists watch for bird flu threat to humans

Avian influenza (bird flu) is not yet a threat to humans, but scientists are watching closely as the virus spreads around the world.

Bird flu is no longer just for the birds. It is increasingly being detected in mammals and, while rare in humans, cases of human infection have a nearly 50% mortality rate, according to a report in the Smithsonian Magazine.

However, these infections seem mostly to have resulted from close contact with poultry and other birds. There is so far no sign of easy human-to-human infection, which would set alarm bells ringing.

“To date, evidence shows that the virus does not infect humans easily and person-to-person transmission appears to be unusual,” the World Health Organisation (WHO) reported in February.

But, with increasing unease, scientists are monitoring bird flu cases in mammals. They urge vigilance about its potential to evolve and spread more easily among humans.

The SA Poultry Association reports that in the United States alone bird flu is being detected in “unusual host species”. These include foxes, bears, coyotes, possums, seals, a leopard and a puma, dolphin, skunks, otters and domestic cats.

So far, there’s no reason to panic about human infections, but vaccine manufacturers are preparing counter measures, just in case.

In South Africa, a bird flu outbreak was detected at Cape Town’s famous penguin colony at Boulders. Scientists expect the virus to reach Antarctica in 2024 and are worried about the impact on huge penguin colonies there.