THINK twice if Dr Mike Leahy invites you for a beer, because you could end up with a hideous parasite growing inside you.

The "mad" scientist - as his brother fondly describes him - talked regulars at the Shaven Crown pub, in Shipton-under-Wychwood, into taking part in a bizarre series of experiments, which involved introducing parasites into their bodies.

But at least Dr Leahy, who has an Oxford University PhD in virology, practised what he preached, by allowing ten different parasites to feed off him at once.

The experiments were carried out at different locations around the county, including Didcot, Bladon and North Leigh, for a new television series called Invasion of the Bodyscratchers, which was shown on Sky TV on Saturday.

For the three-part series, Dr Leahy, 40, who lives in Shipton-under-Wychwood, shared his body with headlice, leeches, bed bugs, dust mites, tics, malarial mosquitos, a two-metre-long tapeworm and a Bot fly.

His brother Aidy, 29, was persuaded to have a live Tunbu Fly inserted into his buttock and his drinking partner Duncan Lonsdale agreed to take part in an experiment to see whether tapeworms, which live in the gut, thrive better on healthy or less healthy food.

Two other customers at the pub were persuaded to become infested with tics and several more agreed to help with an experiment involving bed bugs.

Dr Leahy said: "I have always been interested in infectious diseases and parasites and the best way to see them is on a host.

"I have done experiments like this before, but thought it would be fun to get some other people involved as well.

"I just told them I would make them film stars and they decided to give it a go.

"The wife wasn't too happy at times though - she kicked me out on one occasion and I had to live in a shed at an airbase."

During filming, Dr Leahy met a hospital patient whose foot had become a temporary home to hundreds of maggots, placed on the wound by doctors to suck out an infection.

His brother Aidy said: "I think he's absolutely mad. I wouldn't go through with half the things he's put inside his body.

"I just did it out of interest really. I was apprehensive beforehand, especially when they wanted to put the Bot Fly on my genitals - there was no way I was going to do that - but they assured me it was not one of the nastier parasites, so I agreed to do it."