An outbreak of hepatitis A at a school may have been passed through food eaten in the canteen, Public Health England (PHE) has said.
Eight cases were confirmed at Outwood Academy in Ripon, North Yorkshire, last week.
The number of confirmed cases has risen to 17 following further tests, said Dr Simon Padfield, Consultant in Communicable Disease Control at PHE.
The school declined to comment when contacted by the BBC.
Hepatitis A is a viral infection that affects the liver.
In a letter to parents on Tuesday, the school said data about which foods had been consumed in the canteen was to be reviewed.
“It will be helpful to compare the food eaten by students who are ill and those who are not,” it read.
PHE said those affected were being treated and any health risk was low and Dr Padfield said the school had stopped serving cold food.
“The school has been advised on measures to reduce any further risk, including enhanced deep-cleaning, enhanced hand-washing and, as an additional precaution, the school has stopped serving cold food for this week,” he added.
He said PHE was also investigating three additional cases of hepatitis A confirmed in the Ripon area.
“The source of illness for these cases remains under investigation, and it is not yet known if they are linked to the outbreak connected with the school,” he added.
“Reports of new cases of illness are now beginning to show signs of slowing down, although laboratory testing of further possible cases continues and so additional cases may be confirmed in the following weeks.”
The school has about 650 pupils aged 11 to 18.
Hepatitis A advice
- Hepatitis A is passed from person to person by eating food or drinking water containing the virus
- The virus can spread easily within families and where people live closely together
- The virus is passed out in the faeces so it is important to wash hands after going to the toilet and/or preparing food
- The symptoms of Hepatitis A are similar to flu and include mild fever, joint and muscle pain, feeling and being sick, diarrhoea, loss of appetite and stomach pain
- This can be followed by jaundice (yellowing of the skin and whites of the eyes), dark-coloured urine and itchy skin
- Anyone with suspected Hepatitis A infection should not attend school or work until their doctor advises return