UPDATE: There has been little risk to patients from the low level legionella counts found in Hervey Bay Hospital and Yaralla Place nursing home, the Wide Bay Health and Hospital Service says.
WBHHS public physician Margaret Young said there had been no evidence of any harm.
"Our immediate focus has been to ensure patient safety while the testing program was underway," she said.
"There was little risk to patients due to the low level legionella counts in the identified sites and there has been no evidence of any harm."
Infrequent use of showers can be a major reason for a positive legionella test.
Dr Young said as ward use changed, the demand for a shower could also change.
"Once we had the initial positive results we immediately undertook works that included installing new shower hoses and heads to replace those that had tested positive," she said
"We are doing a supplementary round of testing as a precaution and the results are expected back next week."
Dr Young said new workplace procedures were in place that committed the WBHHS facilities to regular flushing of the water system.
She said there have been no known cases of legionella acquired from public or private hospitals in the Wide Bay area in at least a decade.
Eighty-four tests for legionella in 11 public health facilities across the Wide Bay have returned four positive results.
Low levels of legionella were found in a single shower head at facilities in Mount Perry and Gin Gin, Hervey Bay Hospital, and in a single shower head in Yaralla Place nursing home.
Samples taken after flushing the shower hoses and heads returned negative results at all four facilities.
"Samples taken after running the shower for a minute or two had no legionella which was reassuring as it means our reticulated water systems are free of legionella," Dr Young said.
"Results indicated the bacteria were isolated in the four shower heads."
Bundaberg Hospital, Maryborough Hospital, and the health facilities at Biggenden, Gayndah, Monto, Eidsvold and Childers all tested negative for legionella.
- Legionella bacteria are common in the environment. They can be found in air-conditioning cooling towers, hot or warm water systems, showerheads, spa baths, creeks, soil and potting mix.
- There are various types of legionella bacteria, but the main ones that cause disease in people are legionella pneumophila (often associated with water in cooling towers) and Legionella longbeachae (often associated with gardening or potting mix).
- Legionella is an uncommon cause of serious pneumonia. In the Wide Bay area, there are 3 to 4 confirmed legionella infections each year, of which most are the strain associated with gardening and handling mulch or potting mix.
- Legionnaires disease is a type of pneumonia (lung infection) caused by the Legionella bacteria.
- Legislation requires laboratory-identified cases to be notified to Queensland Health, and all such cases are followed up to determine possible sources.
There is an increased risk of developing legionnaires disease in people over 50 years of age who smoke cigarettes and people with a weak immune system, for example, those with a medical condition such as chronic lung disease, kidney disease, diabetes or cancer.
EARLIER: Legionella bacteria have been found in four Wide Bay hospitals, including the oncology ward at Hervey Bay Hospital.
Low levels of the bacteria, which can cause the potentially fatal legionnaire's disease, were found in initial testing of an unused shower head in the oncology ward.
Secondary testing, to check for further infestation in the ward's pipes, found no further bacteria.
It is understood that one shower head in each of our Wide Bay hospitals were the only legionella infestations found after more than 80 tests in 11 facilities.
Two of those contained the sort of bacteria most associated with the disease.
More details to come.