Villagers say they have been plagued by mysterious insect bites, with some the size of a “tennis ball” requiring treatment for infection.
Children and adults in Airth have had to be treated for up to 20 bites each.
And pharmacist John Porter, from Airth Pharmacy, said he had seen a five-fold jump in the number of people coming to him for help.
He told The Falkirk Herald: “I’ve had to refer some people to the out-of-hours service on a Saturday as the bites were clearly infected and swelling. One was the size of a tennis ball in diameter.
“The bites are not by chance, but we don’t know what is causing them. It’s certainly not midges.”
Samantha Campbell, Lynne Fraser and Alison Patterson and their families – including daughters Chloe Moore (11), Kim Fraser (9) and Emily Patterson (10) – have all been bitten repeatedly over the past few weeks.
Mother-of-two Samantha (42) said: “Most people we have spoke to have been affected. It seems like the whole village has been bitten. Mine were so bad I needed antibiotics.
“We’ve been asking doctors, environmental health and pest control what is causing this but no one seems to be able to identify the bites, which are really sore and get puffy and swollen. Some people counted 17 bites in the space of half an hour. Chloe had nearly 30 bites.”
A spokeswoman for the Scottish Environment Protection Agency (SEPA) said they were not aware of anything in the area that could be causing the bites.
A Falkirk Council spokesman said: “Any enquiry would be passed to our pest control team who advise they have not received any queries.”