4 May 2012 Last updated at 12:22 ET

Stomach illness inquiry at Bishop of Llandaf school, Cardiff

Good hand washing will limit the spread of disease say experts

Public health officials are investigating several cases of stomach illnesses in sixth formers at a Cardiff school.

There has been one confirmed case of cryptospiriodis amongst sixth formers at The Bishop of Llandaf Church in Wales school.

Four other cases are also being looked at amongst pupils who went on a school trip over the Easter holidays.

Symptoms of cryptosporidiosis include watery diarrhoea and stomach cramps.

There can also be vomiting and a slight temperature with symptoms usually appearing within five to seven days following infection.

Dr Gwen Lowe, a consultant in communicable disease control for public health Wales said: "Following a recent school trip we have been notified of several sixth formers who have been experiencing diarrhoeal symptoms with one case confirmed as cryptosporidium.

"Most people with cryptosporidium will recover without treatment, but in individuals with severely weakened immune systems, a more serious illness may develop."

Good hand hygiene precautions will limit the spread of disease, she said.

"People are advised to wash their hands with liquid soap and dry them thoroughly after going to the toilet and before preparing or eating food."

Anyone who is unwell with gastrointestinal symptoms is advised to contact their GP or NHS Direct on 0845 46 47.

People who are unwell with vomiting or diarrhoea should not return to work or school for 48 hours after their symptoms have stopped, Dr Lowe added.