Legionella outbreak spreads

Two more people have fallen ill in South Wales in an outbreak of Legionnaires’ Disease, bringing the total affected to 19, two of whom have died.

Public Health Wales, in collaboration with the Health and Safety Executive and environmental health officers from eight South Wales local authorities, are continuing to investigate the source of the outbreak in the Merthyr Tydfil, Blaenau Gwent and Rhymney areas.

Legionnaires' disease is an infection, caused by the legionella bacterium, characterised by an acute and potentially life threatening pneumonia. It has an incubation period of up to three weeks so more cases are likely to come to light before the source is discovered.

Dr Gwen Lowe, chair of the Outbreak Control Team and consultant in communicable disease control for Public Health Wales, reported that no single building has been visited by all the people linked to the outbreak. “The sources, or source, are therefore likely to be industrial processes such as cooling towers.”

The HSE has inspected all registered cooling towers and evaporative condensers in the area and closed down a site in Dowlais, Merthyr Tydfil because the cooling towers were not being operated in accordance with the approved code of practice. But the site is not confirmed as the source of the outbreak, said Lowe, and once the the tower is cleaned and disinfected in accordance with the ACOP, it will reopen. Three improvement notices were also served on other cooling towers requiring them to improve the operation of their systems.

Samples have been taken from all towers inspected and should be available this week.

“While cooling towers tend to hit the headlines due to mass infection, there is also a very real risk of contracting legionnaires disease from poorly maintained hot and cold water services which are present in almost all buildings," said Gary J Nicholls, managing director of legionella control company Swiftclean. 

"Organisations have a statutory duty to control the risk of the bacteria under the COSHH Regulations as it is a substance known to be hazardous to health, in fact typically 12 per cent of those who contract legionnaires disease die from its effect."

He warned that with public sector cuts looming it is important that facilities managers in the sector do not cut back in this critical area of health and safety control.

The outbreak team have also visited more than 100 other workplaces in the area to try to identify the source.