Bird flu has a new victim: the McMuffin. Across Australia, McDonald’s has slashed its breakfast hours to cope with egg shortages triggered by a mounting bird flu outbreak.

The fast-food giant this week announced that it will temporarily stop breakfast service at 10:30am rather than midday, as avian influenza hits supply chains.

“Like many retailers, we are carefully managing supply of eggs due to the current industry challenges,” McDonald’s wrote in a statement on Facebook.

“We are working hard with our Aussie farmers and supplies to return this back to normal as soon as possible.”

The outlet urged customers to “check the clock” before heading out for breakfast; though, reassuringly for some, “hash browns are still available all day”.

Australia is in the midst of its largest-ever outbreak of bird flu, with more than one million birds culled as officials race to halt the spread.

The virus has been found on poultry farms across Victoria, New South Wales and Canberra, the capital, over the past month, and although less than 10 per cent of Australia’s egg-laying hens have been affected, some supermarkets have imposed limits on how many cartons of eggs people can purchase at once.

“Consumers can expect to see some empty shelves in the short-term, however, supplies are being redirected to areas with short supply,” the Australian government told the BBC, insisting that the situation is under control. “Consumers should refrain from purchasing more eggs than required.”

The current outbreak in Australia is caused by H7, rather than the strain of H5N1, which began circulating worldwide in 2020, and has since killed millions of birds and mammals.

The country did detect a human H5N1 infection in May, but the child had recently returned from India. Still, it marked the first time the highly pathogenic strain of bird flu was detected on the continent.

Internationally, scientists are increasingly concerned about the strain of H5N1 circulating because it has jumped into a growing list of mammals, potentially providing space for the virus to evolve to better infect humans.

Most recently, there has been a huge outbreak in cattle in the United States, with livestock infected across at least 12 states.