South Wales Legionnaires' death of woman, 49
Three people have now died in south Wales this month from Legionnaires' disease but only one death is linked to the current outbreak, say officials.
A 49-year-old woman died on Sunday evening, it was announced on Tuesday.
The deaths of a 70-year-old man and a woman, 64, from Pontypridd, last week are not now being linked to the outbreak.
Investigations are focused on a cluster of seven people linked to Rhymney in Caerphilly county.
There is another potential cluster of four people in the Cynon valley.
Another eight people have various links and connections across the outbreak area.
That makes a total of 19 people with Legionnaires' identified as being linked to the outbreak.
The outbreak area is the corridor 12km (7.5 miles) either side of the Heads of the Valleys road between Abergavenny in Monmouthshire and Llandarcy in Neath Port Talbot.
Health officials said people were linked to the outbreak if they lived in, or had visited, this area in the two weeks before falling ill.
Earlier on Tuesday, Conservative health spokesperson Andrew RT Davies had said people in the Heads of the Valleys area had not had enough information on the outbreak.
He said people needed a more exact idea of the geographical area concerned.
It was announced on Monday that part of a third industrial cooling tower had been shut as a precaution as inquiries continued into the source of the outbreak.
Health officials said part of the tower at a Rhymney valley company was closed before cleaning.
This followed the separate closure of two other towers before they were disinfected.
None of the premises is confirmed as the outbreak's source.
The Health and Safety Executive has inspected all registered cooling towers in the Merthyr Tydfil, Blaenau Gwent and Rhymney area.
Health officials said Legionnaires' had an incubation period of up to three weeks so there were likely to be further cases of illness even after the source was removed.
The public has been told that nobody needed to avoid visiting the area concerned because the risk of contracting the disease remained low.
- BBC One Wales will show a special Week In Week Out programme on the Legionnaires' disease outbreak on Wednesday at 1930 BST.