The results show exposure to the disease

The latest results come after a woman teacher at Portsdown Primary School in Portsmouth was diagnosed with TB on 19 January.

Thirty-six of 60 year six pupils initially tested positive for the bacteria, but only three of these have gone on to develop a form of the disease.

The 11-year-olds are now being treated with antibiotics. None of them is thought to be contagious.

Chest x-rays

The latest group of youngsters and adults to have positive results follows testing of the rest of the school, a health protection agency spokeswoman said.

The group will now be treated with a course of antibiotics to prevent them developing TB.

They will also undergo chest x-rays to see if they show signs of developing the disease.

The skin test which was used, only reveals if a person has been exposed to TB, and not whether they have contracted it.

The health agency spokeswoman said the risk of those who had been infected or exposed to the disease of passing it on was low because TB requires prolonged contact to be caught.

The teacher who originally contracted the disease has not yet returned to work.

About 10% of people infected with the TB bug go on to develop the disease, which attacks the respiratory system and can be fatal if untreated.