Pupils at Leicester's Hamilton College tested for TB
Hundreds of teenagers at a secondary school in Leicester have been tested for tuberculosis after three pupils tested positive for the disease.
Blood tests were carried out on Hamilton Community College's Year 10 pupils.
"It is not that infectious and is easily treated with a course of antibiotics," Health Protection Agency spokesman Dr Philip Monk said.
"[But] we need to investigate and see if any more action needs to be taken."
Dr Monk said parents should continue to send their children to school as the disease is not easily spread.
He said it was not uncommon to find tuberculosis in Leicester as many people have been infected with it while visiting other countries.
It is spread by an airborne germ from someone who already has the disease and symptoms include a prolonged cough, fevers and weight loss.
Some people carry it for six weeks before showing any signs, Dr Monk added.
There were about 200 cases of tuberculosis diagnosed in Leicester in 2011.