Legionella longbeachae detected in an industrial cooling tower linked to a legionellosis outbreak, New Zealand, 2015; possible waterborne transmission?

A legionellosis outbreak at an industrial site was investigated to identify and control the source. Cases were identified from disease notifications, workplace illness records, and from clinicians. Cases were interviewed for symptoms and risk factors and tested for legionellosis. Implicated environmental sources were sampled and tested for legionella. We identified six cases with Legionnaires' disease and seven with Pontiac fever; all had been exposed to aerosols from the cooling towers on the site. Nine cases had evidence of infection with either Legionella pneumophila serogroup (sg) 1 or Legionella longbeachae sg1; these organisms were also isolated from the cooling towers. There was 100% DNA sequence homology between cooling tower and clinical isolates of L. pneumophila sg1 using sequence-based typing analysis; no clinical L. longbeachae isolates were available to compare with environmental isolates. Routine monitoring of the towers prior to the outbreak failed to detect any legionella. Data from this outbreak indicate that L. pneumophila sg1 transmission occurred from the cooling towers; in addition, L. longbeachae transmission was suggested but remains unproven. L. longbeachae detection in cooling towers has not been previously reported in association with legionellosis outbreaks. Waterborne transmission should not be discounted in investigations for the source of L. longbeachae infection.

Atypical pneumonia.

PURPOSE OF REVIEW: We present the key advances in the infections that clinicians conventionally associate with atypical pneumonia: legionellosis, Mycoplasma pneumonia, Chlamydophila species pneumonia and Q fever. RECENT FINDINGS: There have been significant developments in molecular diagnosis to include Mycoplasma pneumoniae and Chlamydophila pneumoniae in multiplex PCR of respiratory specimens. There are diagnostic challenges in distinguishing carriage from infection, which is recognized in C. pneumoniae and now also evident in M. pneumoniae. Macrolide-resistant M. pneumoniae has emerged in Asia. There are new antimicrobials on the horizon in the ketolide class with activity against typical and atypical pathogens and useful empirical agents. SUMMARY: There are few advances in our knowledge of the epidemiology of atypical pathogens or the effectiveness of antimicrobial therapy--empirical or pathogen specific. However, if molecular testing becomes widely implemented, there will be an increased understanding of the epidemiology and presentation of atypical pneumonia and a shift to more targeted antimicrobial therapy.

Prevalence of Legionella strains in cooling towers and legionellosis cases in New Zealand.

Over 3,900 water samples from 688 cooling towers were tested for Legionella in 2008 in New Zealand. Of 80 (2.05% isolation rate) Legionella isolates, 10 (12.5%) were L. pneumophila serogroup 1; 10 (12.5%) were L. anisa; nine (11.2%) were L. pneumophila serogroup 8; and one (1.2%) was L. longbeachae serogroup 2. Forty-one (51.2%) Legionella isolates were L. pneumophila serogroups. Over 3,990 water samples from 606 cooling towers were tested for Legionella in 2009 in New Zealand. Of 51 (1.28% isolation rate) Legionella isolates, 18 (35.3%) were L. pneumophila serogroup 1, and 39 (76.4%) were other L. pneumophila serogroups. L. pneumophila serogroups were significantly associated with legionellosis cases in 2008 and 2009. L. longbeachae serogroups were equally significantly associated with legionellosis cases. This significant association of L. longbeachae with legionellosis particularly of L. longbeachae serogroup 1 is unique in that part of the world. The authors' study also showed that the aqueous environment of the cooling tower is not a natural habitat for pathogenic L. longbeachae. Regular monitoring and maintenance of cooling towers have prevented outbreaks of legionellosis.

[Spa facilities and legionellosis: legislative structure and state of the art in Apulia (Italy)]. / Strutture termali e legionellosi: quadri normativi e stato dell'arte in Puglia.

A number of factors, for example water temperature, can encourage the growth of microorganisms such as Legionella spp in spa facilities. Individuals who attend this type of facility are often subjects at risk for infection who are undergoing inhalation therapy and hot tub treatments. A very accurate management of these facilities is therefore required to avoid infection by Legionella spp. The purpose of this study was to verify the current Italian national and Apulia regional legislation regarding the control of contamination by Legionella spp. in spa facilities.

Legionella longbeachae and legionellosis.

Reported cases of legionellosis attributable to Legionella longbeachae infection have increased worldwide. In Australia and New Zealand, L. longbeachae has been a known cause of legionellosis since the late 1980s. All cases for which a source was confirmed were associated with potting mixes and composts. Unlike the situation with other Legionella spp., L. longbeachae-contaminated water systems in the built environment that cause disease have not been reported. Spatially and temporally linked outbreaks of legionellosis associated with this organism also have not been reported. Sporadic cases of disease seem to be limited to persons who have had direct contact with potting soil or compost. Long-distance travel of the organism resulting in infection has not been reported. These factors indicate emergence of an agent of legionellosis that differs in etiology from other species and possibly in route of disease transmission.

Increase of cases of legionellosis in Latvia, 2011.

An increased number of legionellosis cases in 2011 has been reported in Latvia, compared to the ten previous years. A total of 30 legionellosis cases (1.35 per 100,000 inhabitants), including 19 females, have been confirmed until the end of September 2011. The majority of cases (n=23) were inhabitants of the capital city Riga. The reason for the increase in legionellosis is unclear. Twenty-six of the 30 cases are not travel-related.

Legionella--every infection preventionist's dream--or is it?

Legionella is an underreported disease challenge within the hospital setting. In order to combat Legionella during times of construction and renovation, infection preventionists must become construction experts. The infection preventionist must be able to plan for potential waterborne disease outbreaks and protect the hospital staff, patients and visitors from waterborne pathogens. Legionella's history, signs and symptoms, diagnostic testing and treatment will be discussed. The hospital's convening of a multidisciplinary Legionella task force to work cohesively to develop a waterborne pathogens plan will also be discussed. This article was written from the perspective of the infection preventionist and employee health nurse at the time of the Legionella outbreak at their hospital.

Legionella contamination in the water system of hospital dental settings.

BACKGROUND AND AIM OF THE WORK: Among hospital facilities the dental unit is an environment that is at major risk of Legionella due to equipment such as the air/water syringe, the turbine, the micromotor and the scaler which generate potentially harmful aerosols that may to be a source of exposure to Legionella spp. particularly in immunodeficient patients, and those affected by chronic diseases, and also in dental personnel. Therefore, an examination of the extent of Legionella spp. contamination in the dental chairs waterlines and the incoming water supply of some public dental units is the subject of the present study. METHODS: From February 2002 to March 2004, a total of 208 water samples were collected: 160 samples from the water supply of 4 dental chair and 48 samples from the cold incoming tap water of 2 units. RESULTS: Legionella spp. was detected in 46 samples (22.1% ): 19 of them (41.3% of Legionella spp.; 9.1% of the total) were Legionella pneumophila; Pseudomonas aeruginosa was detected in 86 samples (41.4%) and both microorganisms were detected in 2 samples (0.96%). CONCLUSIONS: Our results show a microbiological condition in dental settings, that is not at all satisfactory due to the presence of Legionella in concentrations that are considered to be a health hazard (> or = 10(3)) in certain cases. Given the extent of the health risk in these surroundings, the difficulty in its assessment, and also considering the wide diffusion of general dental care, our investigation has confirmed the need to regularly monitor the microbiological condition of water in dental units.

[Legionellosis]. / La légionellose.

Although one does not find the origin of the contamination in the human half of the cases of legionellosis, one knows that this disease is the consequence of the almost obligatory contamination of the networks of installations of hot water by Legionella pneumophila, and the inhalation by the man of infected droplets. Pathology generally consists of a relatively serious pneumopathy. The control of the level of contamination of the various producing hydrous installations of aerosols is imperative to avoid the serious medical consequences, which cannot be prevented by an action on the human target. The majority of the currently identified tanks are the air and cool towers and the distribution networks of hot water. The taking into account of this risk in the hospitals or thermal led to the implementation of many measurements of disinfection and control, which start to show a certain effectiveness on which has occurred of new cases in these establishments, today in clear reduction.

Legionella bacteria and water systems in health care premises.

Legionnaires' disease (Legionellosis) is a bacterial pneumonia that acquired its name following an outbreak of pneumonia among army veterans attending an American Legion convention in Philadelphia in 1976. The previously undiscovered bacterium that caused this form of pneumonia was therefore named Legionella. There are more than 45 species of Legionella bacteria and these are natural inhabitants of water supplies throughout the world (Fliermans, 1981). About half of these have been associated with infection, although the most common cause of Legionnaires' disease is Legionella pneumophila, which is the causative strain in around 90 per cent of cases (Fields et al, 2002).

Nosocomial legionellosis: a review of pulmonary and extrapulmonary syndromes.

Surgical patients appear to be at highest risk for acquisition of nosocomial Legionella pneumonia; most appear to become infected during respiratory tract manipulation and mechanical ventilation. Although the lungs are the most common site of nosocomial Legionella infection, an important subset of patients have infection at extrapulmonary sites. We describe 22 cases of extrapulmonary legionellosis reported in the literature. Most of these patients were surgical patients; more than half did not have serious underlying illnesses, and only five (23%) were receiving immunosuppressive agents. A total of 13 extrapulmonary sites of infection were reported, many in the absence of clinical pneumonia; these infections included sinusitis, hip wound infection, and prosthetic valve endocarditis. Five patients (23%) had fatal infections; in four of these cases diagnosis of Legionella infection was made after death, underscoring the need for a high index of clinical suspicion. A large percentage of extrapulmonary Legionella infections may result from direct topical exposure of susceptible tissue to contaminated tap water. Use of tap water must be carefully monitored, particularly in dressing changes and bathing of surgical patients.

Legionella in hospitals: a review.

Although epidemics of nosocomial Legionnaires' disease attract great attention, up to 30% of sporadic cases of hospital-acquired pneumonia are caused by legionellae. Legionellae are ubiquitous contaminants of potable water and can achieve high numbers in the hot-water systems of large buildings such as hospitals. They are present in the mains water supply in small numbers but are amplified considerably in the hospital's hot-water system. This is encouraged by water temperatures below 50 degrees C, areas of stagnation and sludge formation, the presence of amoebae and other bacteria and the materials used in the piping. Formation of aerosols from contaminated water is a major mode of spread of legionellae, but there is evidence to suggest that aspiration is also a mode of entry. Safe levels of legionellae in cooling towers have been defined, but not for hot-water systems. A combination of culture and antigen detection by immunofluorescence offer the best method for enumerating legionellae in environmental samples. Control involves a mixture of physical (heat, UV irradiation, sanitation) and chemical (hypochlorite, ozone) methods combined with good plumbing practice (e.g. arrangement of pumps and calorifiers, elimination of dead-legs). Adequate control can be costly and requires considerable attention to detail.

[An outbreak of legionellosis in a new facility of hot spring bath in Hiuga City].

Following cerebrating ceremony in 20 June 2002, for the completion of Hiuga Sun-Park Hot Spring Bath "Ofunade-no-Yu" facilities, Miyazaki Prefecture, Kyushu Island, 200 neighbors were invited each day to experience bathing on 20 and 21 June. The Bath "Ofunade-no-Yu" officially opened on 1 July 2002. On 18 July, Hiuga Health Center was informed that 3 suspected Legionella pneumonia patients in a hospital and all of them have bathing history of "Ofunade-no-Yu". Health Center officers notified Hiuga City, the main proprietor of the Bath business, that on-site inspection on sanitary managements will be done next day and requested the City to keep the bath facilities as they are. On 19 July, Health Center officers collected bath water from seven places and recommended voluntary-closing of "Ofunade-no-Yu" business. Because of various reasons, Hiuga City did not accept the recommendation and continued business up to 23 July. Because Legionella pneumophila serogroup 1 strains from 4 patients' sputa and several bath water specimens were determined genetically similar by Pulsed Field Gel Electrophoresis of Sfi I-cut DNA. "Ofunede-no-Yu" was regarded as the source of infection of this outbreak. On 24 July, "Ofunade-no-Yu" accepted the Command to prohibit the business. Among 19,773 persons who took the bath during the period from 20 June to 23 July, 295 became ill, and 7 died. Among them, 34 were definitely diagnosed as Legionella pneumonia due to L. pneumophila SG 1, by either one or two tests of positive sputum culture, Legionella-specific urinary antigen, and significant rise of serum antibody titer against L. pneumophila SG 1. In addition to the 8 items shown by Miyazaki-Prefecture Investigation Committee as the cause of infection. Hiuga City Investigation Committee pointed out following 3 items: 1) Insufficient knowledge and understanding of stuffs on Legionella and legionellosis; 2) Residual water in tubing system after trial runs might lead multiplication of legionellae in it; and 3) Inadequate disinfection and washing for whole circulation system prior the experience bathing. The Hiuga City Committee directed 24 measures to improve the sanitary condition of the facility including following 5 items. 1) Fix the manual for maintenance and management of the bath. 2) Keep sufficient overflow of bath water. 3) Put disinfection of filters into practice. 4) Precise measurement and control of the residual chlorine concentration in bath water. 5) Replacement of filtrating material from crushed porous ceramic into natural sand.

[Surveillance and prevention of nosocomial Legionella pneumonia]. / Overvågning og forebyggelse af nosokomiel Legionella-pneumoni.

Statens Serum Institut surveys the occurrence of nosocomial pneumonia caused by Legionella. The rate is low compared to other nosocomial infections but carries a high mortality. Verification of the diagnosis and acquisition (nosocomial or community acquired infection) is carried out in each suspected case. The criteria used for classification are described. Preventive measures include protection of susceptible patients as well as maintenance of the hot-water supply providing a minimum temperature of 50 degrees C at any hot tap. Technical solutions to reduce the concentration of Legionella in hospital hot-water supply systems are listed, and a guideline for the control and surveillance of the occurrence is suggested.

Legionellae.

Legionellae cannot be eradicated from the water supply, since they are naturally occurring and ubiquitous. Routine bacteriologic culturing of man made aquatic environments is not recommended (Soule et al 1995). Therefore any water use that results in production of aerosols should be regularly evaluated to ensure the source has not been contaminated with the bacteria. Any aerosolised water entering a sterile area such as the lungs should be sterile. Tap water should not be used to rinse any respiratory therapy equipment. Routine maintenance of water supplies to eliminate sediment and scale from tanks and trays is essential (Benenson 1995, Lowry & Tompkins 1993). Australian & New Zealand Standard AS/NZ 3666-1995 Parts 1 and 2 outline these requirements.

Effective environmental sampling strategies for monitoring Legionella spp contamination in hot water systems.

BACKGROUND: The prevention and control of legionellosis in hospital settings involves environmental sampling, among other measures. The data yielded by sampling constitute an important means of risk assessment and provide a valid basis on which to plan remedial (cleansing and disinfection) and preventive (maintenance) interventions. This retrospective study had 2 objectives: (1) to evaluate the utility of biofilm sampling at distal sites and (2) to identify an efficient environmental sampling strategy. METHODS: Samples of hot water and biofilm were collected between June 1999 and March 2008 from 41 hospitals in Italy's Piemonte region. We analyzed results of the samples (water and biofilm) taken from the same site and results of the water samples taken from the recirculation loop and water samples taken from the distal sites during the same sampling run. RESULTS: Microbiological analysis was performed on 3910 pairs of samples (water/biofilm). In 81% of the pairs, the results were concordant; in 17% of the pairs, Legionella was isolated only from the water samples, and in only 2% of the pairs was Legionella isolated from the biofilm sample alone. Data from 299 sampling runs show that 79% (236) of results from the water samples taken from the recirculation loop and water samples taken from the distal sites during the same sampling run were concordant, and 21% (63) were discordant. CONCLUSIONS: Our findings suggest that hospitals could safely adopt a simpler (water sampling only without biofilm sampling) and more efficient (monitoring of the entire system through sampling of recirculation loop water) environmental sampling policy.