The US CDC noted that 23% of all Legionnaires' Disease reported in the USA during the 1980s was hospital acquired and that the mortality rate of this was 40%, twice that for community acquired cases. J C Kiosh et al. Nosocomial Legionnaires' Disease. J American Med Assn 1997; 277:1927-8.

Bert F, et al. Multi-resistant Pseudomonas aeruginosa outbreak associated with contaminated tap water in a neurosurgery intensive care unit. Hosp Infec 1998; 39:53-62.

A recent report in the Journal of Hospital Infection describes an outbreak of infection with a strain of Pseudomonas aeruginosa that was resistant to five different antibiotics. 36 patients were involved, nine were simply colonised but 27 were infected; 23 had bacteraemia and pneumonia and 25 had pneumonia. Other sites of infection were the sinuses and urinary tract infection. There was one patient death directly linked to the outbreak. "In this study, the main outbreak strain was isolated from the tap water of two sinks on the ward......"

Dorozynski A, Poor sterilisation of instruments leads to infection outbreak in Paris. Bri Med 1997; 315:699.

At least 31 patients have been infected with Mycobacterium xenopi, a waterborne bacterium in the same family as the TB organism. Contaminated tap water was used to rinse arthroscopes used in orthopaedic spinal surgery, and the patients then developed inflammation and abscesses. An expert on mycobacteria at the French Pasteur Institute is quoted in the article as saying: "The big problem is that the infection is resistant to the usual antibiotics. There is no therapeutic consensus or standard treatment."

Patterson, WJ et al. Colonization of transplant unit water supplies with Legionella and protozoa: precautions required to reduce the risk of legionellosis. J Hosp Infect1997; 37:7-17

Hot and cold water supplies were tested in 69 of 81 UK transplant units. Almost half of the units were found to have their cold (47%) or hot (45%) water contaminated with Legionella species, with L pneumophila in 35% cold outlets and 41% hot outlets. Protozoa were found in 42% cold units and 69% hot units, including 32-54% colonized with the protozoa that act as hosts to Legionella.

CDC Editorial Note on Transmission of Nosocomial Legionnaires' Disease. J American Med Assoc 1997; 277:1927-8.

This paper describes the problem caused by inappropriate filter use in an endoscopy unit. Three different patients were initially diagnosed as having Legionella infection based on bronchoscopy results, but no symptoms developed, so further investigation was carried out. Legionella was found in the water supply and 5µm filters were introduced. The problem recurred and again Legionella was found in the water. The authors note: "The consequences of such endoscope contamination include diagnostic confusion and inappropriate therapy resulting from false positive results and the risk of introducing infection to patients." This report demonstrates that the environment is a potential source of endoscope contamination, and this may still occur despite adequate precleaning and disinfection procedures if non-sterile rinse water is used."

1.  study of Cryptosporidium parvum showed that the normal methods of water treatment do not remove the parasite and warned of the risk of fatal infection in AIDS patients who drink contaminated water. Ann Intern Med 1996; 124:459-68.
2. Two patients died after Legionella infection of wounds following cardiac surgery, two more recovered. N Eng J Med 1991; 324:109-13.
3. Twenty eight patients and three staff developed Legionnaires' Disease in a Swedish hospital, three people died. 17 out of 20 wards in the hospital were found to have Legionella in the hot water supplies. Scand J Infec Dis 1994; 26:417-25.
4. Thirteen cases of Legionnaires' Disease were traced to contaminated water used to wash nebulisers. J Infec Dis 1991; 163:667-71.
5. Legionella pneumonia developed in a premature infant in a unit where the water was found to be contaminated with the same strain of the organism. The child later died from respiratory failure. Eur J Clin Microbiol Infec Dis 1994; 13:565-71.
6. Legionnaires' Disease developed in 13 patients in a renal transplant unit, even though there was no air conditioning or showers, both common routes of transmission of Legionella. The microbe was believed to be dispersed by aerosols from ordinary taps. Krankenhaus-Hygeine + Infection 1993;15:43-7.
7. Pseudomonas aeruginosa infections in burns patients were traced to contaminated water used in hydrotherapy. Clin Infec Dis 1992; 15:941-49.
8. Fourteen patients were wrongly diagnosed as having tuberculosis after contamination of bronchoscopes with other non TB Mycobacterium species. Four patients were given anti-TB therapy until the contamination was identified. Other similar cases are discussed. Chest 1992; 101:1245-9.
9. Five patients with extensive burns developed Pseudmonas aeruginosa septicaemia and four others became colonised. The source was found to be the tap water used to irrigate the burns in the Emergency Department. J Hosp Inf 1993; 24:11-21.

1. ST Goldstein et al. Cryptosporidiosis: an outbreak associated with drinking water despite state-of-the-art water treatment. Ann Int Med 1996; 124:459-468.
2. PW Lowry et al. A cluster of Legionella sternal-wound infections due to postoperative topical exposure to contaminated tap water. N Eng J Med 1991; 324:109-113.
3. Can't find this one. Eliminate reference.(Lancet)
4. J Darelid et al. An outbreak of Legionnaires' Disease in a Swedish Hospital. Scand J Infect Dis 1994; 26:417-425.
5. H Grundman et al. Pseudomonas aeruginosa in a neonatal intensive care unit: reservoirs and ecology of the nosocomial pathogen. J Infect Dis 1993; 168:943-7.
6. PC Luck et al. Analysis of Legionella pneumophila strains associated with nosocomial pneumonia in a neonatal intensive care unit. Eur J Clin Microbiol Infect Dis 1994; 13;565-71.
7. F Allerberger et al. Nosokomiale Legionellenpneumonia bei Nierentranplantieren in Innsbruck. Krankenhaus-Hygeine + Infection 1993; 13:43-7.
8. EE Tredget et al. Epidemiology of infections with Pseudomonas aeruginosa in burns patients: the role of hydrotherapy. Clin Infect Dis 1992; 15:941-9.
9. JGH Gubler et al. Pseudoepidemic of non-tuberculous mycobacteria due to a contaminated bronchoscope cleaning machine. Chest 1992; 101:1245-9.
10. HJ Kolmos et al. Outbreak of infection in a burns unit due to Pseudomonas aeruginosa originating from contaminated tubing used for irrigation of patients. J Hos Infect 1998; 39::53-62.