Legionnaires' total in south Wales rises to 19 cases
Two more cases of Legionnaires' disease have been identified as part of an outbreak in south Wales, which is linked to two deaths.
All 19 cases have required hospital treatment and some remain seriously ill.
Public health experts expect the number of cases to rise over the next week and haven't ruled out further deaths.
Safety officials have checked all registered cooling towers in the area being investigated.
Giving its latest daily update on the outbreak Public Health Wales (PHW) said there were four cases of Legionnaires' disease possibly linked to the outbreak.
These cases remain under investigation.
Two of the four people have died. A 70-year-old man died in hospital on 8 September, and a 64-year-old woman died in hospital on 6 September.
Meanwhile a team of more than 100 staff from 10 agencies have been working to find the source of the outbreak, which is believed to be in the Merthyr, Rhymney or Blaenau Gwent areas.
Health officals said information had been gathered on those with the disease to identify where they had been at times when they may have caught the infection.
After it became evident that there was no single building visited by all the people linked to the outbreak, the investigation focused on checking systems with the potential to spread legionella.
Health and Safety Executive (HSE) officers have visited a total of 10 registered cooling towers and evaporative condensers in the Merthyr Tydfil, Blaenau Gwent and Rhymney area.
One company in the Rhymney valley voluntarily shut its cooling tower as a precaution after samples were taken.
Three unregistered premises with cooling towers and/or evaporative condensers were also identified and visited.
Notices were served on three companies running registered premises requiring them to improve their operation of their systems.
The cooling towers were not being operated in accordance with HSE guidelines, said officials.
A cooling tower in Merthyr was shut down but the company was able to restart work after cleaning and disinfecting it.
However, the site, at Dowlais, was not confirmed as the source of the outbreak.
Environmental health officers have ensured that samples have been taken from a number of sites to try and identify whether the Legionella bacterium is present.
Results are not yet available.
More than 100 other workplaces in the area have also been visited and a further improvement notice was enforced during these checks.
However officials underlined that premises which have received enforcement action or had samples taken were not necessarily linked directly to the outbreak.
Dr Gwen Lowe, chair of the outbreak control team and consultant in communicable disease control for Public Health Wales, has advised members of the public not to change their normal behaviour as a result of the outbreak.
She said the risk of contracting Legionnaires' disease from visiting the area remained low.
Information has been circulated to GPs advising of the steps to be taken if patients have symptoms. A fact sheet is being circulated in the communities affected.
Anyone who is concerned about their health should contact their GP or NHS Direct Wales on 0845 46 47.
The councils involved in the investigation include Cardiff, Merthyr Tydfil, Rhondda Cynon Taf, Caerphilly, Blaenau Gwent, Torfaen and Monmouthshire.
Last year, there were 24 confirmed cases of Legionnaires' disease in Wales, most of which were sporadic. On average, Wales has about 13 cases each year.