Swimming Pool Blog
by Rob Cox, March 18, 2013
Pool Pathogens and Bacteria ~ There's a Fungus Among Us!
Bacteria and viruses can easily find a home in swimming pool water. I'm not speaking about algae, which is not a pathogen (disease causing organism), but smaller, invisible creatures that can live in your pool or spa.
The CDC (Center for Disease Control) records thousands of cases of disease outbreak in pools and spas every year. They also monitor public pool health inspection reports. In a recent study, as many as 60% of public pools had violations.
Parasites, bacteria and viruses in swimming pools can lead to fever, vomiting and diarrhea in mild cases. More acute symptoms can lead to hospitalization and in rare cases can cause death.
Bacteria in My Pool?
Water is a breeding ground for bacteria and can support viruses and parasites long enough for them to enter your body through absorption, inhalation, and/or ingestion.
In the presence of chlorine, fungi is the most vulnerable, followed by bacteria. Viruses can take 10 times longer to be neutralized by chlorine, and protozoa is the most resistant, taking up to 100x longer than a fungus to be zapped by your pool chlorine.
Not surprisingly, the pathogens that take the longest time to kill also produce the most dangerous water borne illnesses.
How can Pool Water Become Contaminated?
Fecal contamination is a leading cause of pathogens in pool water. Swimmers who don't wash their backsides before swimming or after using the bathroom (#2), are unknowingly rinsing off in the pool. It is estimated that the average waterpark facility has several pounds of fecal matter daily to deal with from their visitors. Yuck!
Accidental Fecal Release (AFR - a real term) is another method of entry. People with diarrhea should not use the pool for two weeks, to avoid an accidental release.
Aside from fecal matter, swimming pools can become contaminated by vomit, sweat, urine or saliva from an infected human or animal.
Parasitic infections can enter a swimming pool from food, particularly raw and uncooked proteins, such as eggs or fish, or can be brought into a pool from insects and wildlife that may fall into the pool.
Fill water can sometimes be the culprit, especially water that may have to travel far from the water treatment plant, or water from a contaminated well.
How can Swimmers Become Infected?
It depends on the pathogen. The most usual way is to swallow contaminated water, even small amounts that splash into your mouth and mix with your saliva. Some microbes can enter through the skin or through cuts on the skin. Eye, nose, ear and throat are the usual entry points.
How can Pool Water Contamination be Prevented?
In most cases of micro organism outbreaks in swimming pools, nearly all in fact - the level of disinfectant is not high enough to combat the level of organisms. Filtering and circulation are also important to remove contaminants and distribute sanitizer. So, it's real simple really...
- Keep your chlorine level constant, at 1.0 ppm or higher.
- Shock your pool regularly to remove the unseen danger.
- Filter all of your pool water 1-2 times daily.
- Shower before you use the pool.
- No Dogs, No Babies. No Diarrhea. ;-)
Can Pool or Spa Water be Tested for Bacteria?
Well, I'm glad you asked! In fact, we have a bacteria test strip that you can use to test your pool or spa water for the presence of Coliform, E.Coli, Shigella, Pseudomonas and many other types of bacteria than can lead to RWI (Recreational Water Illness). Easy to use; returns results in just minutes.
Types of Bacteria found in Pools and Spas
Shigella - bacteria that can infect the digestive tract and cause a wide range of symptoms, from diarrhea, cramps, vomiting, to more serious illnesses. Infections, called shigellosis, sometimes go away on their own; in others, antibiotics can shorten the course of the illness. Other symptoms of shigellosis include: high fever, loss of appetite, and painful bowel movements. In very severe cases of shigellosis, a person may have convulsions (seizures). Shigella is transmitted directly from uncleaner swimmers and may infect after ingestion of contaminated food or water. This pool pathogen may be acquired by swimming in contaminated surface waters or pools and spas.
Moral: Keep your pool and spa water balanced and sanitized, shock regularly, and washing well before using the pool can prevent RWI (Recreational Water Illness). To prevent contamination from an accidental release (AFR), persons with Diarrhea should not use the pool for a period of two weeks.
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