May 28, 2021

Legionnaires’ disease - Problems and incidence

By Dr. Volker Luibl, MBA Cytiva

Legionnaires’ disease is likely underdiagnosed - Learn about the rise and growth of this infectious disease.

If Coronavirus has made anything clear, it is that infectious diseases are here to stay, can pop up at any moment, and every country that is unprepared for the threat will end up paying a steep price. One such underestimated problem is Legionnaires’ disease, as a report by the European Centre for Disease Prevention and Control (ECDC) highlighted (1).

What’s the problem?

Unfortunately, there is a lack of high-quality evidence and epidemiological data on infectious diseases. This makes it harder for healthcare experts to decide how best to allocate a country’s resources for the prevention and control of infectious diseases.

What did the ECDC report set out to do?

The report estimated the burden of 31 diseases using “disability-adjusted life years” (DALYs) in the EEA area (EU + Norway, Iceland, and Liechtenstein). DALYs describe the impact of “years lived with disability” (YLD) following the onset of a disease and of “years of life lost” due to premature mortality (YLL) compared with a standardized life expectancy.

What were the main results, and how does Legionnaire’s Disease fit in?

  1. Legionnaires’ disease has a relatively low incidence, but it is also (and perhaps surprisingly) the disease with the 3rd highest premature mortality, after rabies and diphtheria.
  2. In terms of mortality and incidence, Legionnaires’ disease is the 5th largest disease after the “big four” (Influenza, Tuberculosis, HIV/AIDS, Invasive Pneumococcal Disease) in terms of burden, with 10 annual DALYs per 100,000 populations (Fig 1).
  3. Together with tuberculosis, HIV/AIDS and IPD, Legionnaires’ disease is classed as a disease with a high population burden and a high individual burden (Fig 2).

What’s the status in the US?

In the United States, the number of cases of Legionnaires’ Disease reported to the CDC (Centers for Disease Control and Prevention) has been on the rise since 2000 and has grown by nearly nine times since then. Health departments reported nearly 10,000 cases of Legionnaires’ disease in the United States in 2018. However, because Legionnaires’ disease is likely underdiagnosed, this number may underestimate the true incidence.(2)

What’s the take home message?

There is a significant burden associated with Legionnaires’ disease in Europe. Countries would do well to allocate resources to combat the increasing spread of this disease in an adequate and timely manner.

Explore our solutions


  1. Cassini A, Colzani E, Pini A, Mangen MJ, Plass D, McDonald S, et al. Impact of infectious diseases on population health using incidence-based disability-adjusted life years (DALYs): results from the Burden of Communicable Diseases in Europe study, European Union and European Economic Area countries, 2009 to 2013. Euro Surveill. 2018;23(16):17-00454.
  2. Center for Disease Control (CDC). History, Burden, and Trends. Updated [2021 Mar 25]. Accessed 2021 Mar 27].

Author bio

Dr. Volker Luibl head shot

Dr. Volker Luibl, MBA, Dr. Luibl is a Demand Generation Marketing Manager at Cytiva with knowledge in medical device and clinical science.