Recreational Water Illnesses (RWIs)
Recreational water illness (RWIs) facts
*Recreational water illness facts Medically Edited by: Melissa Conrad Stöppler, MD
- Contrary to popular belief, chlorine does not kill all germs instantly. There h
are germs today that are very tolerant to chlorine and were not known to cause
human disease until recently. Once these germs get in the pool, it can take
anywhere from minutes to days for chlorine to kill them. Swallowing just a
little water that contains these germs can make you sick.
- Recreational water illnesses (RWIs) are caused by germs spread by swallowing,
breathing in mists or aerosols of, or having contact with contaminated water in swimming pools, hot tubs, water parks, water play areas, interactive fountains,
lakes, rivers, or oceans. RWIs can also be caused by chemicals in the water or
chemicals that evaporate from the water and cause indoor air quality problems.
- RWIs include a wide variety of infections, including gastrointestinal, skin,
ear, respiratory, eye, neurologic, and wound infections. The most commonly
reported RWI is
diarrhea. Diarrheal illnesses are caused by germs such as
E. coli O157:H7.
- In the past two decades, there has been a substantial increase in the number
of RWI outbreaks associated with
Crypto, which can stay alive for days
even in well-maintained pools, has become the leading cause of swimming
pool-related outbreaks of diarrheal illness. From 2004 to 2008, reported Crypto
cases increased over 200% (from 3,411 cases in 2004 to 10,500 cases in 2008).
- Although Crypto is tolerant to chlorine, most germs are not. Keeping chlorine
at recommended levels is essential to maintain a healthy pool. However, a 2010
study found that 1 in 8 public pool inspections resulted in pools being closed
immediately due to serious code violations such as improper chlorine levels.
- With RWI outbreaks on the rise, swimmers need to take an active role in
helping to protect themselves and prevent the spread of germs. It is important
to learn the basic facts about RWIs so you can keep yourself and your family
healthy every time you swim.
- Knowing the basic facts about recreational water illnesses (RWIs)
can make the difference between an enjoyable time at the pool, beach, or water
park, and getting a
rash, having diarrhea, or developing other, potentially
Viewers share their comments
Recreational Water Illnesses - Sources
Question: If known, where did you contract your recreational water illness (RWI)? Please share your experience.
Recreational Water Illnesses - Chlorine
Question: What types of pool chemicals do you use? Has anyone ever gotten an RWI from your pool or spa?
Recreational Water Illnesses - Prevention
Question: In what ways do you try to prevent RWIs? Please describe your experience.