Is rain seeding cooling towers with legionella? - Legionella

Is rain seeding cooling towers with legionella?

A Proposal:
I suggest that public health research microbiologists study the relationship between rainfall and Legionella colonization of cooling towers / evaporative condensers leading to subsequent community acquired Legionnaires’ disease cases.

My Observations:
During research of Legionella numbers in a cooling tower published in 1985, I observed [but did not include the rainfall data] that the numbers of Legionella in the cooling tower were greater after a rain storm.
Disinfection of circulating water systems by ultraviolet light and halogenation. Richard W. Gilpin, Susan B. Dillon, Patricia Keyser, Alice Androkites, Mary Berube, Nichola Carpendale, Jane Skorina, James Hurley, and Adele M. Kaplan. 1985. Water Research. Vol. 19, Issue 7, Pages 839-848.
I have also noticed that my commercial clients sometimes have higher legionella counts in their cooling towers after significant rainfall [unpublished observations].

My Background:
After receiving a PhD in Microbiology and Public Health from Michigan State University and accepting a two-year NIH NIGMS Research Fellowship, I joined the microbiology faculty at a medical school in Philadelphia. I was involved with the investigation of the 1976 Legionnaires’ disease outbreak by collaborating with an engineering consulting company, a water treatment company, and research faculty at other medical schools in Philadelphia. I began bench research testing of environmental water samples for legionella in 1979 while collaborating with Dr. James Feeley at the Special Pathogens Laboratory, Centers for Disease Control and Prevention. I established ‘GTS Legionella Testing Service’ in 1981 and have tested thousands of samples.

Existing Publications Pointing to Rain / Legionella / Cooling Towers / Community Cases:
Publications covering rainfall delivery of Legionella to cooling towers and subsequent community cases appear to be increasing.

Extreme Precipitation and Legionnaires Disease Hospitalizations in Boston, Massachusetts from 2002-2012. Megan Kowalcyk, Varun Patel, Elizabeth Hilborn, and Timothy J. Wade. Environmental Health Perspectives.

Increased rainfall is associated with increased risk for legionellosis LA Hicks, CE Rose, BS Fields, ML Drees… – Epidemiology & …, 2007 – … deficiencies in the treatment of potable water supplies must occur concurrently with heavy rains to result … If Legionella were to increase in potable water supplies after heavy rain– fall, it is … Our evidence suggests that heavy rainfall is associated with increased risk for legionellosis …

  Rainfall Is a Risk Factor for Sporadic Cases of Legionella pneumophila Pneumonia C Garcia-Vidal, M Labori, D Viasus, A Simonetti… – Plos one, 2013 –… Moreover, when there is heavy rain and/or a risk of flooding, each community adopts different measures at its water purification … Our findings of a sustained rise in the number of LP cases during warm and rainy periods strongly suggest that … (2007) Increased rainfall is associated …

 The Impact of Storms on Legionella pneumophila in Cooling Tower Water, Implications for Human Health RL Brigmon, CE Turick, AS Knox… – Frontiers in …, 2020 – … concentrations during this time even through exposed to similar wind and rains from the … this time of extreme weather, conditions including summer weather, high rainfall, increased humidity … in a cooling tower as a function of extreme weather conditions, including rain and wind …

  Environmental sources of community-acquired legionnaires‘ disease: A review LT Orkis, LH Harrison, KJ Mertz, MM Brooks… – International journal of …, 2018 – Elsevier … From 2000 to 2014, the reported annual rate of legionellosis in the US, which … of sporadic Legionnaires‘ disease rates by postal code, L. pneumophila and other Legionella spp … these geographic variations suggest cooling towers as a primary source of Legionnaires‘ disease in …

  Large community-acquired Legionnaires‘ disease outbreak caused by Legionella pneumophila serogroup 1, Italy, July to August 2018 M Faccini, AG Russo, M Bonini, S Tunesi… – …, 2020 – … As reported in a recent review, warm weather, rain and higher relative humidity may have an impact on the survival of airborne Legionella, as it has been shown to survive better at a … Rainfall is a risk factor for sporadic cases of Legionella pneumophila pneumonia …

Investigation of atmospheric conditions fostering the spreading of Legionnaires‘ disease in outbreaks related to cooling towers D Villanueva, K Schepanski – International journal of biometeorology, 2019 – Springer … Legionnaires‘ disease (LD) is transmitted through the inhalation of bioaerosols from water managing devices containing Legionella pneumophila, a … found a strong correlation between
the relative humidity (RH) and the sporadic cases of legionellosis in Philadelphia …

  Ten questions concerning the aerosolization and transmission of Legionella in the built environment AJ Prussin II, DO Schwake, LC Marr – Building and environment, 2017 – Elsevier