For sufferers of holiday tummy, relief may be at hand. Scientists have developed a vaccine patch that can cut the incidence of traveller's diarrhoea by 75 per cent.

Traveller's diarrhoea lasts on average between four and five days, involves 18 trips to the loo and leaves sufferers dehydrated and debilitated.

The patch, worn on the upper arm, delivers a tiny dose of toxin produced by E. Coli bacteria, the most common cause of diarrhoea, which stimulates the body's immune response. It is applied for a six-hour period three weeks before travel. A "booster" dose is delivered through a second patch applied one week before travel.

A trial using 170 volunteers in America found it significantly reduced the incidence and severity of diarrhoea. Researchers from the IOMAI Corporation in Gaithersburg, Maryland, found 21 per cent of those given a placebo had a moderate to severe attack of diarrhoea, compared with 5 per cent of those who received the vaccine. The results are published in the journal The Lancet.