81 cases have now been confirmed in a cryptosporidium outbreak linked to a farm shop in Cowbridge.
Public Health Wales (PHW) confirmed seven new cases following a meeting of its outbreak control team on Wednesday.
The outbreak stems from visits to Marlborough Grange Farm, where public feeding and petting sessions involving calves and lambs was stopped voluntarily on April 29th.
The farm shop's owners are co-operating with the ongoing investigation and health officials are warning the public to take hygeine precuations before visiting farms.
Beverley Griggs, a health protection consultant at PHW, said: “We are continuing to work with our partners to investigate this outbreak and to reduce the risk of further transmission."
“Cryptosporidium infection often clears up without treatment, but it can be more serious for vulnerable people."
“We advise anyone who visited the farm and is experiencing symptoms such as diarrhoea, stomach pain or nausea to contact their GP or call NHS 111 Wales.”
Cryptosporidium is a parasite that can cause gastrointestinal illness. It is often linked to contact with animals, especially young farm animals such as calves and lambs.
It can last for up to a fortnight and symptoms usually begin around two to ten days after contact - but the infection can still spread after symptoms subside and anyone affected should not go swimming for a fortnight.
The main symptoms of cryptosporidium include watery diarrhoeam, stomach pains or cramps, nausea or vomiting, a loss of appetite and weight loss and mild fever.
Public Health Wales says it advises anyone visiting farms to follow good hygiene practice, such as washing your hands throughly after touching animals, boots or clothing and before eating or drinking.
They advise parents to supervise children closely to ensure they wash their hands properly while pregnant women should take particular care and avoid contact with newborn lambs during the lambing season.
Cardiff and Vale University Health Board and Vale of Glamorgan Council are working alongside PHW as part of their investigation into the outbreak.

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