Parents with children at a private Harrow school have been notified of a confirmed case of hand, foot, and mouth disease among pupils.
The John Lyon School, in Middle Road, is also dealing with two suspected cases of the viral infection.
In a letter sent to parents on Wednesday, including Brent families, the school said: "You should be aware that there has been one confirmed and two suspected cases of hand, foot and mouth disease within the school."
A common childhood illness, hand, foot and mouth disease can affect adults and normally lasts between seven and 10 days.
Symptoms include a sore throat, a high temperature above 38C, a loss of appetite, mouth ulcers and a rash.
The school note added: "If your child is unwell and presents with these symptoms, please keep them at home and inform the School through your son's form tutor.
"The treatment is the same as the flu virus: rest, good hydration and regular analgesia."
The school said it has no further comment to make.
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