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Diary Entry #4: Legionella Biography

Posted on by Robyn McDaniel

Dear Diary,

Here is a biography on my microbe:

Legionella pneumophila is transmitted airborne via water droplets. There were 6,100 cases of Legionnaires’ disease reported in the year of 2016. The following symptoms show after two to 14 days after exposure: high fever, chills, coughing, muscle ache, headache, shortness of breath, and fatigue; symptoms typically take seven days to show. The CDC can analyze Legionnaires’ disease via chest x-rays, phlegm, blood, or urine. Those at risk are 65 or older, have weakened immune system, smoke, or have lung disease. Legionnaires’ disease is treated by 1 to 3 weeks on a drip or tablet antibiotic, majority of patients make a recovery. Health authorities must be notified if a case of Legionnaires’ disease is diagnosed to trace the source of the outbreak. Interesting enough, Legionella pneumophila is very common in rivers and ponds, but the numbers are low, it’s considered harmless.

Places/areas/surfaces L. pneumophila can be transmitted:

Water systems in hotels (Primary outbreak)

Legionnaires’ disease got its name in 1976 when the first outbreak affected 182 people attending the American Legion Convention hosted in Philadelphia; this outbreak killed 29 people. The outbreak’s source was the convention hotel’s air conditioning system, as well as contaminated water or mist.

The Bellevue-Stratford Hotel, location of the first Legionnaires’ disease outbreak

Cruise ships (yup, in the middle of the ocean)

CDC reported during November 2003 through May 2004, eight cases of Legionnaires disease (LD) had a common factor and emphasized the need for identification and reporting of cases to facilitate the investigation.

Hospitals

Fourteen patients, three patients died due to other health conditions, after contracting Legionnaires’ disease in a UW Health hospital at the end of 2018 in Madison, Wisconsin. After the outbreak, the hospital eliminated the bacteria by clearing the hot water system with high levels of chlorine.

Me on the way out, avoid the outbreak

Grocery store mist machines

Louisiana had 34 patients diagnosed with Legionnaires’ Disease during October and November of 1989. Most patients shopped at a Winn-Dixie grocery store for roughly 30 minutes within ten days of onset symptoms. The patients were shopping for produce items near or at the mist machines. Researchers determined that aerosols from the mist machine were the cause of the outbreak, leading to thousands of grocery stores discontinuing produce mist machines.

Nursing home

Two patients in Richlandtown, PN living in a care center were infected with Legionnaires’ disease during January of 2019, one passing away due to other health factors. Another nursing facility was affected on April 22 of this year in Albert Lea, Minnesota. One of the residents at St. John’s Fountain Lake senior community has contracted Legionnaires’ disease at the facility; there have been five cases between June and August of summer 2018.

Also, pool or bath toys (throw the cute rubber ducky away), swimming pools (just in time for spring/summer), hot tubs (how romantic), whirlpools, cooling towers in air conditioning units, decorative fountains, and physical therapy equipment are known surfaces used to transmit Legionnaires’ disease.

Even Disneyland?!

Disneyland had a L. pneumophila outbreak during September of 2017. 9 of 12 patients experiencing symptoms visited Disneyland and the remaining three live or traveled to Anaheim, California; one of the patients has passed away. Orange County Health Care Agency stated the Legionnaire’s was discovered in late October. Disneyland had high levels of bacteria found in its two cooling towers; therefore, they were closed and sterilized and were shortly reopened.

References

Addmaster. “Ten Facts About Legionella.” Addmaster Additives for Industry, www.addmaster.co.uk/biomaster/bacteria-facts/ten-facts-about-legionella.

Ellison, Ayla. “3 Patients Die after Contracting Legionnaires’ Disease in Wisconsin Hospital: Fourteen Patients Contracted Legionnaires’ Disease during an Outbreak Linked to the Water System at UW Health’s University Hospital in Madison, Wis., and Three of Those Patients Have Died, According to the Wisconsin State Journal.” Becker’s Hospital Review, 18 Dec. 2018, www.beckershospitalreview.com/quality/3-patients-die-after-contracting-legionnaires-disease-in-wisconsin-hospital.html.

Legionnaires’ Disease News. “Albert Lea Nursing Facility Hit Again.” Legionnaires’ Disease News, 22 Apr. 2019, www.legionnairesdiseasenews.com/2019/04/albert-lea-nursing-facility-hit-again/.

Legionnaires’ Disease News. “First 2019 Outbreak Results in Death in Pennsylvania.” Legionnaires’ Disease News, 11 Jan. 2019, www.legionnairesdiseasenews.com/2019/01/first-2019-outbreak-results-death-pennsylvania/.

Live Science. “5 Things You Should Know About Legionnaires’ Disease.” LiveScience, Purch, 28 Aug. 2012, www.livescience.com/22760-5-things-you-should-know-about-legionnaires-disease.html.

Mahoney, F J, et al. “Communitywide Outbreak of Legionnaires’ Disease Associated with a Grocery Store Mist Machine.” The Journal of Infectious Diseases, U.S. National Library of Medicine, Apr. 1992, www.ncbi.nlm.nih.gov/pubmed/1552203.

Naham, Matt. “Disneyland Legionnaires’ Disease Outbreak: 5 Things to Know.” AJC, Cmgsharedcontent.com, 12 Nov. 2017, www.ajc.com/news/national/disneyland-legionnaires-disease-outbreak-things-know/zLqvS3pDryw25d8xKN1g0H/

Diary Entry #3: Legionella In Greater Detail

Posted on by Robyn McDaniel

Dear Diary, 

Legionella pneumophila grows in a new host and prefers an amoebic host cell within a biofilm. L. pneumophila attached to the amoebic host and exhausts all resources then turns to motile dispersal phase where it breaks the cell wall to find a new host. It then uses its flagellum to reach the lower respiratory of the new host. L. pneumophila is spread via aerosol droplets and is suspended in air or other gas; the bacterium can be found in any water source. The Legionella antigen and DNA can be detected in both motile or replicative phase. 

Legionella pneumophila showed growth in a chemically defined medium; the medium contained 21 amino acids and inorganic salts. L. pneumophila grew in a liquid defined medium at 37°C and in a complex media, with four isolates, with a 6-hour generation time. The strain of L. pneumophila tested was not stated. Researchers specified the L-Serine, L-methionine, and L-cysteine amino acids were essential for ideal growth. A chemostat catalyzed growth in natural environments with limited resources, at the same temperature rate yielded 38% more culture compared to normal conditions.

 

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In vivo, L. pneumophila replicated via pinching binary fission, intra- and extracellularly. Legionella also underwent non-septate binary fission, producing identical cells. L. pneumophila does not grow spores throughout its life cycle, but it does grow spore produces spore-like laminated envelopes or coats, which function similar to gram-positive spores. The bacterium typically replicates between 25 to 47 degrees, pH levels of 5.5 to 9.2, and the oxygen level concentration between 6.0 to 6.7 mg/liter. Legionella did not replicate in tap water with a concentration less than or equal to 2.2 mg/liter of dissolved oxygen. Rutgers University studied specific strains of L. pneumophila, Gt4, and Gt15. The Gt4 strains of L. pneumophila showed growth between 25 and 30°C while the Gt15 strains grew between 42 and 45°C. The in vivo temperature growth was consistent with the temperature tested at water distributors.

Robyn

 

P.S. Here is an animation of Legionella

 

Here a video on Legionella’s replication

 

Reference

Faulkner, G., and R. A. Garduno. “Ultrastructural Analysis of Differentiation in Legionella Pneumophila.” Journal of Bacteriology, vol. 184, no. 24, 2002, pp. 7025–7041.

Rodgers, F. G., and M. R. Davey. “Ultrastructure of the Cell Envelope Layers and Surface Details of Legionella Pneumophila.” Microbiology, vol. 128, no. 7, 1982, pp. 1547–1557.

Sharaby, Yehonatan, et al. “Temperature-Dependent Growth Modeling of Environmental and Clinical Legionella Pneumophila Multilocus Variable-Number Tandem-Repeat Analysis (MLVA) Genotypes.” Applied and Environmental Microbiology, American Society for Microbiology, 31 Mar. 2017, www.ncbi.nlm.nih.gov/pmc/articles/PMC5377503/.

Wadowsky, R M, et al. “Effect of Temperature, PH, and Oxygen Level on the Multiplication of Naturally Occurring Legionella Pneumophila in Potable Water.” Applied and Environmental Microbiology, U.S. National Library of Medicine, May 1985, www.ncbi.nlm.nih.gov/pmc/articles/PMC238529/.

Warren, W J, and R D Miller. “Growth of Legionnaires Disease Bacterium (Legionella Pneumophila) in Chemically Defined Medium.” Journal of Clinical Microbiology, U.S. National Library of Medicine, July 1979, www.ncbi.nlm.nih.gov/pmc/articles/PMC273092/.