According to Public Health England (PHE), a hepatitis A outbreak at a school could have been caused by food consumed in the canteen.
Eight cases were confirmed last week at the Outwood Academy in Ripon, North Yorkshire.
The number of confirmed cases has risen to 17 after further testing, Dr. Simon Padfield, a consultant on communicable disease control in PHE.
The school claimed to be kept informed about the situation on a regular basis.
Hepatitis A is a viral infection that affects the liver.
In a letter to parents on Tuesday, the school said the data on which foods were consumed in the canteen should be checked.
"It will be helpful to compare foods eaten by sick students and those consumed by non-sick students," she added.
A spokesperson for the academy said, "We are deeply upset with the recent outbreak and wish them all the best for their recovery.
"We came in contact with those concerned and updated them regularly."
Hepatitis A piece of advice
- Hepatitis A is transmitted from person to person by eating food or drinking water containing the virus
- The virus can spread easily in families and in places where people live closely together
- The virus is excreted in the feces, so it is important to wash your hands after using the toilet and / or preparing food
- The symptoms of hepatitis A are similar to the flu and include mild fever, joint and muscle pain, nausea, diarrhea, loss of appetite and stomach pain
- This can be followed by jaundice (yellowing of the skin and whites of the eyes), dark urine and itchy skin
- People with suspected hepatitis A infection should not go to school or work until their doctor orders them to return
Source: NHS England
The school, which is open as usual, said it continues to work with PHE and the County Council to identify the possible cause of the outbreak and to ensure that necessary action is taken.
According to PHE, those affected are treated and the health risk is low. According to Dr. Padfield has stopped school serving cold food.
"The school has been advised on measures to reduce further risks, including improved deep cleansing, improved hand washing, and as an added precaution, it has stopped serving cold food this week," he added.
Dr. Padfield said PHE also investigated three additional cases of hepatitis A confirmed in the Ripon area.
"The cause of the disease for these cases is still under investigation and it is not yet known if it is related to the school-related outbreak," he added.
"New case reports are now showing signs of slowing down, although the laboratory investigation of other possible cases is continuing and therefore more cases may be confirmed in the following weeks."
The school has about 650 students aged 11 to 18 years.
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