Four people in Ireland have been infected with salmonella, in an outbreak that has already claimed one life in England.

The Republic's Food Safety Authority of Ireland (FSAI) confirmed yesterday that it was investigating an outbreak that could be linked to the consumption of watermelon.

It said four cases of salmonella newport had been confirmed in Ireland, and the UK authorities were also investigating an outbreak affecting 35 people, while 15 cases have been reported in Germany since December. This is three times higher than is normally expected in a two-month period.

A total of 26 cases have been confirmed in England, three in Wales, one in Northern Ireland and five in Scotland.

One person has died in the British outbreak, but that person had serious underlying health complications, the UK's Food Standards Agency said.

The FSAI said that investigations into the source of infections were continuing but early indications suggested "a possible link with watermelon".

"Information from the Health Protection Surveillance Centre to the FSAI confirms that the last Irish case occurred at the beginning of January 2012.

"All indications suggest that there is no longer contaminated product on the market," it said.

Infection causes diarrhoea, vomiting, abdominal pain and fever and usually resolves within four to seven days.

In more severe cases, antibiotics are sometimes necessary, plus further complications such as blood poisoning or localised infection can also arise.

The FSAI advised any consumers who felt unwell after eating watermelon to consult their doctor as a precaution.

However, it said it was not issuing a recall at this point.

The UK's Health Protection Agency said that watermelons could have been contaminated during the cutting process, by transferring salmonella from the surface to the flesh, or the bacteria could have got inside the fruit via the cut stem if they were washed or stored in contaminated water.

It said the risk of becoming unwell after eating watermelon was low, but it was always advisable to wash fruits and vegetables, including watermelon, before consumption.