A “small number” of tuberculosis (TB) cases have been reported after testing at Blackwood Comprehensive School, Public Health Wales (PHW) has announced.

The testing programme was carried out after a TB case, linked to the school, was discovered last month.

All pupils and teachers who came into contact with the individual were offered screening for TB. 

The screenings took place on Tuesday, January 25. The first confirmed case was announced by PHW five days earlier.

However, Dr Lika Nehaul, of Public Health Wales, said the cases discovered are of a non-infectious form of the virus.

Dr Nehaul said: “We have identified a very small number of individuals whose results are indicative of latent TB infection.

“The cases identified are of the non-infectious form of TB and therefore pose no risk to the wider community. These individuals have been informed and have been offered clinical care and support following long established clinical guidelines.”

Dr Nehaul added: “Given the very small number of cases of latent TB infection, we have not recommended further screening in the school, but will continue to monitor the situation and have informed local GPs.

“Due to the low numbers involved and to protect the privacy of those concerned, we will not be providing any further updates on these cases.”

An investigation into the confirmed case is being carried out by PHW, Aneurin Bevan University Health Board and Caerphilly County Borough Council.

Caerphilly Observer asked PHW for the exact number of cases recorded during the testing programme at the school. In response, PHW said due to the “very low number of cases identified and to protect the identity of the individuals involved,” it cannot confirm the exact number.

However, PHW reiterated no outbreak has been declared.

What is tuberculosis?

Tuberculosis (TB) is a bacterial infection which mainly affects the lungs, but can also affect the abdomen, glands, bones and nervous system.

It is spread by inhaling droplets from the coughs or sneezes of an infected person.

Symptoms of TB include a persistent cough lasting more than three weeks, bring up bloody phlegm, weight loss, night sweats and a high temperature.

Other symptoms include tiredness and fatigue, loss of appetite and swelling in the neck.

While TB can be a serious condition, it can be cured if treated with the right antibiotics, according to the NHS website.

A course of antibiotics is usually needed for six months to treat the infection.

Isolation is not needed for people with TB, but it is recommended anyone infected should stay away from work or school until advised otherwise.

Infected people are also advised to cover their mouths when sneezing or coughing, avoid sleeping in the same room as others and to keep windows open to allow air to flow.

According to the NHS website, most healthy people will be able to kill the bacteria and therefore show no symptoms. People who have TB but show no symptoms are not infectious to others.