Legionella bacteria are present in natural aquatic environments and can contaminate public water systems, especially piping, wells, reservoirs and swimming pools. Not all species are dangerous to humans; the responsible for most of the epidemics in the world is Legionella pneumophila of serogroup 1.
Although epidemiological surveillance of Legionellosis has greatly improved in recent years, it is a disease that remains under-diagnosed and even under-reported. The latest data are contained in the 2015 epidemiological report produced by the European Center for disease prevention and control: it reports 7,034 cases of Legionellosis in the European economic area, with 69% of cases in France, Germany, Italy and Spain. The number is growing and the report assumes that this is attributable to the improvement of surveillance systems, but also to:
- aging of the population,
- increase of travel,
- climate changes.
The latter in particular (higher incidence of storms and high temperatures) create an environment favorable to the development of the bacterium, but also lead to the increase in the use of air conditioning systems, where Legionella can proliferate. The study emphasizes that regular and appropriate control measures on drinking water and water intended for human use are decisive for the prevention and control of the disease.
Legionellosis was detected especially in collective accommodation facilities such as hotels, home accommodation, cruise ships, spas, swimming pools, hospitals; these are at-risk environments that must undergo regular checks.
The Guidelines for the control of Legionellosis were issued by the World Health Organization at global level, by the EWGLI (the European Group on Legionella infections) at European level and by each State. In Italy, Legislative Decree no. 81/2008 includes Legionella among the risks to be monitored and managed in the workplace. In particular, it mentions the need for checks in tourist, collective and health facilities to be carried out at least twice a year.
Mérieux NutriSciences performs tests on Legionella according to the international standard ISO 11731:2017
The test is performed on water, swabs, scales and biofilms in swimming pool water, reservoirs, taps, drains of air conditioning systems, etc. As for water, the analysis is accredited and the result is both qualitative (absence/presence of bacteria) and quantitative.
In Italy, Mérieux NutriSciences follows the “Guidelines for the prevention and control of Legionellosis” published in 2015 by the Ministry of Health and it performs sampling on request, besides general tests.
Mérieux NutriSciences’ proposal for Legionella also includes the possibility of identification through MALDI-TOF –a fourth-generation rapid system for the identification of microorganisms accredited for the Legionella species, which allows the analysis of colony isolation in a plate in case of suspected presence of the bacterium.
