More Ysgol y Strade pupils in Llanelli offered TB screening
Screening for tuberculosis (TB) is being offered to a further 224 pupils at a comprehensive school in Carmarthenshire after a staff member was diagnosed with the infection.
In October, 122 children and 29 members of staff were screened for TB at Ysgol y Strade, Llanelli.
Three of those pupils and a member of staff tested positive, but none are believed to be infectious and there is no ongoing risk within the school.
Up to 80 staff could also be screened.
Sion Lingard, acting consultant in health protection for Public Health Wales (PHW), said TB can be treated with antibiotics.
"We are emphasising to pupils, parents and staff that it is rare for TB to be transmitted within a school environment," said Mr Lingard.
"Further screening is being carried out due to the very small risk that others may have picked up the infection within the school.
"All those who are likely to have had some form of contact with the infectious staff member will be screened.
"Close contact with an infectious individual over a long time period, such as living in the same household, is usually required for a person to become infected with TB.
"The infection is difficult to catch but treatable with antibiotics."
The latest round of screening is for those who have had less contact with the member of staff.
Mr Lingard added the case at the school was not linked to another four cases of TB in the Llanelli area over the last 12 months.
TB is an infection usually found in the lungs, but any part of the body can be affected.
People can catch TB by breathing in the bacteria in tiny droplets sneezed or coughed out by someone who has the infection in their lungs.
The most common symptom of TB is a persistent cough for more than three weeks, with spit which can sometimes be blood-stained.
Other symptoms can include weight loss, a high temperature, and sweating, particularly at night.
PHW said anyone who is concerned about their health should speak to their GP or contact NHS Direct Wales on 0845 46 47.