“Despite substantial advancements in understanding Legionella transmission since the first identified outbreak in 1976 at the American Legion convention in Philadelphia, crucial research gaps in prevention and control measures remain, which hamper efforts to reduce the recurring surge in cases. Recent global outbreaks in 2024 highlight the urgent need for heightened awareness and preparedness among health-care professionals and the community.”
Since November last year we’ve had reported outbreaks in China, Australia and the USA, with, over the last month:
- In London, Ontario, the Middlesex-London Health Unit (MLHU) has recently declaring the end of the Legionnaires' disease outbreak that killed 3 people and infected 70. The outbreak started in early July, the source has, as yet, not been found.
- An ongoing outbreak investigation in Central Harlem, New York, with, so far, at least 90 people infected, with 3 fatalities.
For England and Wales, the 604 reported cases of Legionnaires’ disease is the highest we’ve seen and continues an unwelcome upward trend. Although of course recognising that the majority of actual cases, potentially up to 6,000 a year, go undiagnosed.
If history is to be proved accurate, we are in the time (June to Sept) when numbers of reported cases in the UK are at their highest annually. And in addition to the point made in the Lancet above another factor, much less in our control, could also be a factor, the weather.
Periods of warmer, wetter, weather would easily be seen as conducive to Legionella outbreaks, with the temperature encouraging growth and the moist air dissemination of contaminated droplets. With our Summer already being characterised with warm and wet periods, we may yet again join the unwelcome list of having another outbreak.
If you haven’t already, review your risk assessment, and written scheme to make sure it is suitable, sufficient and up to date (have there been changes?), and check your controls to identify if any of your systems, or parts of them, may be showing some of the adverse temperature effects of the weather. Oh and did I mention training, when was the last time you had yours?