How To Protect Swimmers From Cryptosporidium In The Pool?

In Blog by Timothy Petsch

Cryptosporidium-big word, little bug, bad news! Cryptosporidium (Crypto) chatter is everywhere in the professional pool world right now, and for good reason. According to the NSPF CPO handbook, cryptosporidium was one of two parasites responsible for 66% of commercials swimming pool related gastroenteritis outbreaks, and remains active at normal disinfectant levels for days. So let’s take a moment here to dig into where crypto comes from and why, and how we can protect our swimmers from this potentially fatal infection.

What is crypto? Crypto is a protozoan parasite and is about 4 to 6 microns in size. For comparison, a grain of table salt is approximately 100 Microns in size. Generally, cryptosporidium is transmitted from animal feces, and after being transmitted to humans will enter pool water through human feces.

Why is crypto a problem? Cryptosporidium lives in the lower intestine for around a week during its incubation period. Following that, healthy people will have a rough 2+ weeks of moderate to severe stomach cramps, diarrhea, and vomiting.-not a pleasant process, by any means. But the real concern is the very young, or people with weak or compromised immune systems, since in those cases a crypto infection can prove fatal. In fact, an outbreak in 1993 in Milwaukee killed over 100 people! Clearly, guarding against crypto is not to be taken lightly.

What can we do? Crypto has a hard outer shell that makes it pretty resistant to chlorine, and one diarrheal release can up to one billion oocysts (organisms), which is a formidable army for the operator to have to overcome. Add to that massive number the fact that only 10 organisms can create an infection, and you have a justifiable reason to be on guard. Here are a few actions you can take to be better protected:

  • Make sure your chlorine is always at a safe level (1-3ppm) and you pH is 7.2 to 7.4.
  • Don’t allow diapers in the pool.
  • Post a sign in the changing room asking bathers to shower before entering the water, and to shower their children. The sign might also ask that if they have had a recent gastrointestinal or diarrheal incident to not use the pool for 2 weeks after symptoms have gone.
  • Consider adding a Ultra Violet system. Ultra Violet light has been proven to inactivate cryptosporidium, and provides the added benefit of reducing combined chlorine in the water.
  • Evidence is beginning to indicate that crypto can be captured by the proper filter media. Ask your chemical provider about a filter enhancer so that you can trap the organisms in the filter bed. We have a single stage product called “Filter Aid” that will trap to 1 to 2 microns, which, in theory, is tight enough to capture the crypto in the filter when used correctly. Other chemicals are coming onto the market to combat this increasing occurrence.

  Using all these suggestions in tandem will allow you to be as protected as you can be, and as we all know, protecting the health and welfare of our swimmers is Priority One for pool operators.