Parents of children at a West Drayton primary school said they have been left with concerns after a pupil was diagnosed with meningitis and another was suspected of having it.
Laurel Lane Primary School issued no formal warnings to parents but some removed their children from classes in reaction to the news.
One parent, who wished to remain anonymous, told getwestlondon they had taken their child out of school on Tuesday (January 9) despite the head of school telling parents "meningitis is not contagious".
The parent said: "Parents were not informed about the meningitis although regarding something minor like head lice there are always letters at the first sign of a child having them."
They went on to say that they are "very concerned" about their child's safety.
The school was unable to confirm whether sick pupils had been in class "due to data protection reasons".
Advice issued by the National Union of Teachers states: "When a case of meningitis occurs, it is important that parents, pupils and staff are fully and regularly informed."
Sandra Voisey, head of school at Laurel Lane Primary School at West Drayton, confirmed that pupils had contracted a strain of meningitis and parents were not informed.
"Last Friday evening (January 5) after school we were informed that one child had meningitis and then we were informed of a possible second case on Sunday," she said.
"This case was not confirmed by Health Protection and we contacted them for advice on what to do.
"They reassured us that children, parents and staff were not in any danger and that no further action was needed.
"Had there been any risk the school would have taken appropriate action."
Health Protection has been contacted for comment.
What is meningitis?
Meningitis is a contagious bacterial or viral infection in the protective layers surrounding the brain and spinal cord and is most common in babies and young children.
It can be spread by sneezing, coughing, kissing or sharing of cutlery, utensils or a toothbrush.
Symptoms of meningitis include a high temperature above 38C, a headache, stiff neck, a dislike of bright lights and seizures.
While a blotchy rash that does not go away when a glass is rolled over it is one of the best known symptoms, it does not always develop.
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