Center for Disease Control and Prevention (CDC) issued "Outbreaks Associated with Treated Recreational Water-United States, 2000-2014"on May 18, 2018.

Michele C. Hlavsa, MPH et al. collected the date from 46 states and Puerto Rico during 2000-2014. During these years, 493 outbreaks associated with treated recreational water caused at least 27,219 cases and 8 deaths.  According to the study, outbreaks associated with exposure to treated recreational water can be caused by pathogens and chemicals in venues such as pool, hot tubs/spas, and interactive water play venues.

From this study, authors found the result that are below;

●493 outbreaks in 15 years (2000-2014)

●27,219 people sick and 8 people deaths linked to pools, hot tbs, and water playground

●Most outbreaks happen in hotel pools and hot tubs in the summer(June - August)

There are three thins to stay healthy in the water;

１．Do not swim with Diarrhea

２．Check the inspection score

３．Do not swallow the water

363 out of 493 outbreaks with confirmed infectious etiology.

１．212 out of 363 outbreaks were caused by Cryptospordium.  It causes predominantly gastrointestinal illness.

２．57 out of 363 cases were caused by Legionella.  It causes Legionnaires’ disease, a severe pneumonia, and Pontiac fever and so on

3．47 out of 363 cases were caused by Pseudomonas. It causes folliculitis and otitis externa.

参考文献（References）

CDC(Center for Disease Control and Prevention)

https://www.cdc.gov/media/releases/2018/p0517-swimming-related-diseases.html

https://www.cdc.gov/mmwr/volumes/67/wr/mm6719a3.htm?s_cid=mm6719a3_w

レジオネラ症

https://www.niid.go.jp/niid/ja/diseases/ra/legionella/392-encyclopedia/530-legionella.html

493 outbreaks associated with treated recreational water during 2000-2014

157(32%) of the 493 outbreaks were occurred at Hotels

275(56%) outbreaks started during June and August

46(9%) outbreaks started in March

Public Health Officials from 46 states and Puerto Rico(2000-2014)

Total the 363 outbreaks with a confirmed infectious ethiology;

212(58%) of the 363 outbreaks were caused by Cryptosporidium.

57(16%) of the 363 outbreaks  were caused by Legionella.

47(13%) of the 363 outbreaks were caused by Pseudomonas.

The 363 outbreaks identified 24,453 cases;

21,766(89%) were caused by Cryptospordium

920(4％) were caused by Pseudomonas

624(3%) were caused by Legionella