Category Archives: Legionella

Europe – Legionnaires’ disease – Annual Epidemiological Report for 2017


Publication series: Annual Epidemiological Report on Communicable Diseases in Europe
Time period covered: This report is based on data for 2017 retrieved from The European Surveillance System (TESSy) on 13 July 2018.

Research – Legionella & Fire Sprinkler Systems – Is there a Risk?

Legionella Control Legionella A

Legionella is a bacterium that is commonly found in natural water sources such as lakes, reservoirs and rivers, usually in small concentrations that pose no threat to public health. However, once this water enters man-made water systems such as fire sprinkler systems, under certain environmental conditions there is a risk that any Legionella bacteria that are present in the water may proliferate, increasing the risks associated with Legionnaires’ disease.

Fire sprinkler systems do present a legionella risk and so sprinkler maintenance routines should be amended and incorporated in to the legionella monitoring and control programmes that you currently have in place.

USA – Illinois: Another Legionnaires’ disease cluster reported

Outbreak News Today


legionellacIn a follow-up to the recent Legionnaires’ disease clusters in Illinois, state and county health officials are investigating a cluster of three cases at McHenry Villa, an independent senior living community.

Public health officials confirmed the third case this week. McHenry Villa is notifying residents, the residents’ identified contact, and staff.  All three cases had outside exposures, and two of the cases had potential exposures at Centegra Hospital-McHenry.  Public health officials will continue to investigate any other potential sources.

Information – How Many Legionella Species Exist & Which Ones Cause Legionnaires’ Disease?

Legionella Control Legionella A

While there are more than 50 different recognised Legionella species, less than half of those can cause illness in humans. However, while around 20 species are known to be harmful to us, just one has been identified as the cause of most outbreaks of Legionnaires’ disease. Read further at the link above.

Information – How Temperature Influences Legionella Growth

Legionella Control Legionella_Plate_01

In this review the experts at Legionella Control International look at how water temperatures influence legionella growth and how this information can be used to control the risks from the bacteria.

Under certain circumstances Legionella bacteria can lead to serious illness and fatalities in humans. Since Legionella bacteria can exist in man-made water systems, it is imperative to ensure the water is stored, maintained and distributed at temperatures that do not encourage the growth and spread of the bacteria.

There are three temperature ranges that have an influence on the growth and proliferation of Legionella bacteria. Read at the link below.

USA – Legionnaires’ disease: Lower Washington Heights cluster rises to 14

Outbreak News Today Legionella_Plate_01

In a follow-up on the Legionnaires’ disease cluster reported in Lower Washington Heights in northern Manhattan, New York City health officials report the case count has risen to 14.

The Health Department is actively investigating these cases and is sampling and testing water from all active cooling tower systems in the area of the cluster.

This is the second Legionnaires’ disease cluster reported in Lower Washington Heights this year.

Legionnaires’ disease is a type of pneumonia that is caused by the bacteria Legionella, which grows in warm water. Symptoms resemble other types of pneumonia and can include fever, chills, muscle aches, and cough. Most cases of Legionnaires’ disease can be traced to plumbing systems where conditions are favorable for Legionella growth, such as cooling towers, whirlpool spas, hot tubs, humidifiers, hot water tanks, and evaporative condensers of large air-conditioning systems.

Individuals may be infected by breathing in water vapor containing Legionella, and the disease is not transmitted from person to person. Individuals at higher risk include those ages 50 and above, cigarette smokers, and people with chronic lung disease or compromised immune systems. People living or working in the area who are experiencing these symptoms should seek medical attention with a primary care provider or seek urgent care.

Information -Do Ice Machines Spread Legionnaires Disease?

Legionella Control Legionella_Plate_01

Ice machines and chilled water dispensers are becoming increasingly popular both at home and in the workplace where they are used for a variety of purposes. At first glance, the freezing water temperatures used to create ice would suggest that opportunities for bacterial growth would be very limited and so the risks to people using them insignificant. However, this may not always be the case and here we consider if ice machines can spread Legionnaires’ disease.

Ice machines and chilled water dispensers offering ice or cold water do so at temperatures well below the 20-degree threshold for concern. However, each machine contains a mechanical compressor that is used to lower water temperatures. The heat given off by a compressor may be enough to warm the water inside the machine, thereby allowing Legionella bacteria to grow and multiply unseen. The bacteria could then potentially reach levels in the water where it may prove concerning for those drinking it or taking ice from the machine.

A similar scenario could occur if the machine is positioned in a warm spot, i.e. near to a radiator or other source of heat.