6.3. Legionella

The ignorance of the health/sanitary issues, bad system design and failure to ensure proper cleaning may turn out negative not only for the clients impression about your accommodation, but also for their health. In unhygienic conditions there is a risk that some serious diseases, e.g., legionellosis, can occur.

What is Legionaire’s disease?

Legionnaire’s disease is a lung infection caused by a bacterium named Legionella pneumophila. Cases of this disease occur worldwide due to poor design and maintenance of the water distribution system.

Legionellosis symptoms:

Symptoms appear 2-10 days after exposure to the bacteria. In the early stage the symptoms are non-specific and may include fever (>39 C), weakness, fatigue, loss of appetite, cough, or stomach discomfort, nausea, diarrhoea, headache, muscle pain, breathing difficulty. If the illness is determined at an early phase and treated with antibiotics, the outcome is normally good, though the complete recovery might take up to a year. If the immune system of a person is compromised due to a chronic lung disease, smoking, a transplant, or delay in therapy, complications and death may follow.

Source of disease:

The major source is water distribution systems. Legionella bacterium colonize water storage tanks, hot water heaters, pipes, filters, and outlets including taps and showerheads. Sediment accumulation, stagnation of water and temperature between +20 C - +50 C favour bacteria’s growth. The systems with disregard of regular cleaning and use of solar heat might provide such favourable conditions.

For remote areas, the problem is with quick diagnosing of the illness, since the equipment for specialized laboratory tests that is necessary is not available in many hospitals.

For the prevention of Legionella growth, the accommodation owners with their own water distribution system should take a number of measures. These can be easily implemented and involve mostly proper routine maintenance.

How to prevent Legionella’s growth:

The sediment from the aerators on the taps/shower heads should be regularly removed.

Hot water storage tanks and boilers should be fitted with a drain valve located at the lowest point so that accumulated sludge can be easily removed. Draining and cleaning should be done quarterly.

All cold water storage tanks should be cleaned and disinfected annually.

If some part of the hot water system is out of use for a week or longer, the temperature of the water in the system should be raised up to +60 C before bringing it back to use for prophylactic purposes.

Generally, the distribution system should be designed with as few dead legs (laterals that are infrequently used) as possible, since Legionella can boost in these stagnant sections.

In case of discovery of the bacteria in the water system, active measures throughout the system are to be applied – chlorination, installation of instantaneous heating systems, repeated temperature raising up to +70 C with flushing of all faucets and showerheads for 30 min, etc.

Nowadays many large tour operators cooperating with independent accommodations in rural areas require the implementation of basic prevention measures. Also, at the EU level the guidelines for the control and prevention of travel-associated Legionnaire’s disease are adopted as an official document. According to the established procedures, the responsible agency in the country urgently visits and inspects the accommodation site that has had two or more cases of legionellosis within 2 years. At the same time, the accommodation has to undertake immediate measures. In some countries, these can be subsidized. If no or inadequate measures are carried out by accommodation or incomplete investigations are reported by the country agency within 2 weeks while the accommodation remains open, the EU Committee applies the method of “naming and shaming” by making the accommodation name public as representing risk to tourist health.