Bite from ‘lone star’ US tick can trigger meat allergy for life

A TICK that makes people vomit when they eat red meat is spreading across the United States.

Just one bite from the “lone star tick”, named for the white spot on its back, can trigger a life-long allergy known as alpha-gal syndrome (AGS).

It originates from the alpha-gal sugars the tick ingests when it feeds on mammals, such as mice, rabbits or deer. When the tick then bites a human, it can inject the sugars into them through its saliva. Humans do not have alpha-gal in their bodies, so the immune system will fight back and develop antibodies.

People with the syndrome experience allergic reactions to meat, from anaphylaxis to stomach problems, hives and headaches. It can be difficult to diagnose as reactions can happen hours after the meat is ingested.

The link between the syndrome and the tick was first studied in 2019 in the south-east of the US. But the bug has now moved north, as far as Washington DC, because of a warming climate. Rising temperatures mean that the bug can now live through the winter.

Between 2010 and 2018, 34,000 cases of AGS were reported. Health officials have warned people to take care on grass in the spring and summer when the ticks are especially aggressive.