Identifying and Combating Waterborne Diseases

The ability to recognize and prevent common waterborne diseases will make you a better pool operator.

 

These days, it takes more than creative programming, management skills, and knowledge of waterborne diseases, water sanitation and filtration to make a great public pool operator.

With today’s increased focus on the transmission of waterborne diseases, pool operators must possess knowledge of various diseases and effective public relation skills to interact with and assure a concerned public regarding the safety of their pools.

To help you become more informed on, we’ve put together a guide of five waterborne diseases: E. coli, Pseudomonas, Cryptosporidium, Giardia and Legionella. We’ve designed this waterborne diseases guide to provide fast, useful information that covers the dangers of each disease, how to safeguard your pools and how to properly sanitize infected water.

It’s important to note that many factors influence a waterborne diseases survivability in pool water. The resistance to bacteria to chemical action many vary greatly among different species, different strains of the same species and different cultures of the same strain. A large number of organisms responsible for swimming-related illnesses may be relatively resistant to chlorine based on their capsular material, the clumping of the organisms, the presence of natural products from bather and the use of cyanuric acid to stabilize chlorine. Additionally, the small size of the pathogens makes them difficult to remove through filtration.


Escherichia coli

What is it? Escherichia coli, commonly know as E. coli, are coliform bacteria living in the digestive tracts of humans and other animals. Coliform bacteria are aerobic and anaerobic, gram-negative, rod shaped, nonspore-forming and highly motile bacteria. The hundreds of forms of E. coli include 0157:H7, the strain responsible for a toddler’s death last summer. Most forms of this strain remain harmless, residing in healthy human intestines. E. coli 0157:H7, however, can cause serious illness.

Why is it dangerous/what is its effect on bathers? Swimmers who swallow contaminated water can contract the bacterial waterborne diseases. Severe, bloody diarrhea; abdominal cramps; and fever characterize E. coli infection. Those with impaired autoimmune systems, such as chemotherapy and HIV patients, may experience further complications that can lead to kidney failure.

How can it get into pool water? Transmission occurs through introduction of fecal matter in to poorly treated pool water. Although young, nontoilet-trained children are the most common culprits, fecal contamination can occur through deposit of fecal droppings from animals, rodents and birds; guests or staff tracking fecal matter into the pool area on their shoes; fertilizers or grass blown into the pool from adjoining landscaping; supply water taken from contaminated ground water, reservoirs or wells; rain and storm water run-off; and illegal cross-connections between pool circulation and sewage systems.

How can you safeguard your pool against it? To protect your pool, maintain proper, recommended sanitation levels. In addition, make clear that people who have experienced any symptoms of diarrhea within the past two weeks should not enter the pool. Require non-toilet-trained children to wear swimsuit diapers or tight fitting rubber or plastic pants. Post signs that ask patrons to shower before entering the pool.

What are some indications that it’s in your water? There are no good, consistent indications that E. coli exists in your pool. Any suggestion of fecal contamination should be handled immediately, as this could lead to possible infection.

How can you test for it? Administering a general bacteria test is the best way to ascertain the presence of E. coli. Although no simple bacteria test specifically checks for E. coli, the tests for total bacteria will alert you of any harmful bacteria in the water. State and private laboratory facilities may also perform test to determine E. coli’s presence.

If present, how do you remove it from pool water? Remove any visible fecal debris and superchlorinate the water. Keep swimmers out of the water for at least 30 minutes. If loose, watery stools are found in the water, close the pool, create a concentration-over-time (CT) value of 9,600, turn over the pool three or four times, dechlorinate the pool and restore water balance before reopening.


Pseudomonas aeruginosa

What is it? Pseudomonas aeruginosa is an aerobic, rod-shaped, gram-negative bacterium present in the environment as well as in human skin and gastrointestinal tracts.

Why is it dangerous/what is its effect on bathers?Pseudomonas most often shows itself as a dermatological problem resulting in a red, bumpy, itchy rash, which looks like measles. Other symptoms include earaches, breast inflammation, flu-like symptoms, conjunctivitis, coughing and sore throat, urinary tract infections, and nausea.

How can it get into pool water? The skin, nose, throat and feces of infected individuals can transport Pseudomonas to water, and it can pass into water through broken pool-circulation pipes or from dirt tracked onto the deck. Pseudomonas can also grow in filter lines, garden hoses and lane lines coiled on the deck.

How can you safeguard your pool against it? Maintain proper, recommended sanitation levels. Also, institute rigorous deck maintenance procedures and request that individuals shower before entering the pool. Because Pseudomonas is more prevalent in warm water, shock your spa daily.

What are some indications that it’s in your water? Severe skin irritation and fair-to-poor water clarity are common signs that Pseudomonas exists in your water. Bathers that spend extended time in warm water and staff members who wear wet bathing suits throughout their shifts are likely to experience symptoms.

How can you test for it? A general bacteria test should determine the presence of Pseudomonas. Pool operators can run simple tests – remember to collect samples from inside the filter and the hair and lint strainer. State and private laboratory testing can also determine whether your water is infected – be sure to specifically request that the lab check for both the presence and the quantity of Pseudomonas.

If present, how do you remove it from pool water? To remove infection, superchlorinate the water, vigorously clean all surfaces and change the filter media. Extreme cases may require draining the pool and scrubbing the surface. Spas should always be drained and scrubbed following an outbreak.


Cryptosporidium

What is it? Cryptosporidium, commonly known as “Crypto,” is a protozoan parasite that can live in human and animal intestines. Only the species Cryptosporidium parvum is known to cause infection in humans.

Why is it dangerous/what is its effect on bathers? A strong outer shell, called an “oocyst,” makes Crypto highly resistant to the levels of sanitizer commonly found in a pool. In some cases, it may take as long as six or seven days in a properly sanitized and filtered pool for Crypto to be completely killed.
Two to ten days after accidental ingestion of Crypto, a disease called “cryptosporidiosis” may develop. Symptoms include diarrhea, upset stomach, cramps and fever. Some who ingest Crypto may not get sick; nonetheless, they may still carry and transmit the parasite. People with weakened immune systems, including HIV, chemotherapy and transplant patients, will have a much harder time recovering from illness. Small children and pregnant women can quickly become dehydrated.

How can it get into pool water? Transmission occurs through introduction of fecal matter into poorly treated pool water. Although young, nontoilet-trained children are the most common culprits, fecal contamination can occur through deposit of fecal droppings from animals, rodents and birds; guests or staff tracking fecal matter into the pool from adjoining landscaping; supply water taken from contaminated ground water, reservoirs or wells; rain and storm water run-off; and illegal cross-connections between pool circulation and sewage systems.

How can you safeguard your pool against it? To protect your pool, maintain proper, recommended sanitation levels. In addition, make it clear that people who have experienced any symptoms of diarrhea within the past two weeks should not enter the pool. Require the wearing of swimsuit diapers or tightfitting rubber or plastic pants by children not yet toilet trained. Post signs that ask patrons to shower before entering the pool.

What are some indications that it’s in your water? There are no good, consistent indications that Crypto is present in your pool. Any suggestion of fecal contamination should be treated immediately, as this could lead to possible infection.

How can you test for it? A general bacteria test can best ascertain the presence of Crypto. Although no simple test exists that specifically targets Crypto, a total bacteria test will alert you to any infiltration of harmful bacteria in your water. State and private laboratory facilities can test for the presence of Crypto. By the time you suspect Crypto, however it will most likely be dead.

If present, how do you remove it from pool water? Remove any visible fecal debris and superchlorinate the water. Keep swimmers out of the water for at least 30 minutes. If loose, watery stools are found in the water, close the pool, create a concentration-over-time (CT) value of 9,600, turn over the pool three or four times, dechlorinate the pool and restore water balance before reopening.


Giardia

What is it? Giardia is a parasitic protozoan that causes giardiasis, a gastrointestinal illness. It’s found in human and animal feces.

Why is it dangerous/what is its effect on bathers? Giardia requires high doses of chlorine and extended contact time to kill. Ten days after the parasite is ingested, individuals may experience diarrhea, gas, bloating, weight loss, fatigue and fever. Those with impaired immune systems may develop additional symptoms, and the duration of the illness may be longer. The average duration is one week.

How can it get into your pool water? Transmission occurs through introduction of fecal matter into poorly treated pool water. Although young, nontoilet-trained children are the most common culprits, fecal contamination can occur through deposit of fecal droppings from animals, rodents and birds; guests or staff tracking fecal matter into the pool area on their shoes; fertilizers or grass blown into the pool from adjoining landscaping; supply water from contaminated ground water, reservoirs or wells; rain and storm water run-off; and illegal cross-connections between pool circulation and sewage systems.

How can you safeguard your pool against it? To protect your pool, maintain proper, recommended sanitation levels. In addition, make it clear that people who have experienced any symptoms of diarrhea within the past two weeks should not enter the pool. Require the wearing of swimsuit diapers or tightfitting rubber or plastic pants by children not yet toilet trained. Post signs that ask patrons to shower before entering the pool.

What are some indications that it’s in your water? There are no consistent indications that Giardia resides in your pool. Any indication of fecal contamination should be handled immediately, as this could lead to possible infection.

How can you test for it? A general bacteria test is the best method of determining Giardia’s presence. Even though no simple test exists that specifically targets Giardia, a total bacteria test will alert you to any infiltration of harmful bacteria in your water. State and private laboratories can also test water for the presence of Giardia.

If present, how do you remove it from pool water? Remove any visible fecal debris and superchlorinate the water. Keep swimmers out of the water for at least 30 minutes. If loose, watery stools are found in the water, close the pool, create a concentration-over-time (CT) value of 9,600, turn over the pool three or four times, dechlorinate the pool and restore water balance before reopening.


Legionella

What is it? The gram-negative, rod-shaped bacterium Legionella pneumophila causes the infection legionellosis. The disease has two distinct forms: Legionnaires’ disease, the more severe form of infection, and Pontiac fever, a milder illness. Legionnaires’ disease acquired its name in 1976 when an outbreak of pneumonia occurred among persons attending a convention of the American Legion in Philadelphia. Later, the bacterium causing the illness became known as Legionella. It’s found in natural environments such as soil and water.

Why is it dangerous/what is its effect on bathers? Legionella affects humans through inhalation; the bacterium gets inside airborne droplets and can cause bronchial disease when inhaled. Once it gets airborne, Legionella can be transmitted through air-handling systems. Two to ten days after exposure, individuals may develop body aches, diarrhea, headaches, fatigue, stomach cramps, cough and weight loss. The disease can develop into pneumonia.

How can it get into pool water? Legionella exists throughout source water. It survives in water temperatures roughly between 80 and 104 degrees F, meaning spa temperatures are ideal for growth. Spas are also likely transmitters because spa jets can aerosolize the bacteria. Multiuse pools with warmer-than-normal temperatures also pose a threat.

How can you safeguard your pool? Protect your pool and spa by maintaining proper, recommended sanitation levels, and ensure that you have uniform sanitation – Legionella can grow in pool’s “dead” spots. Disinfect and backwash your filters regularly because the bacterium can grow in filters.

What are some indications that it’s in your water? There are no good, consistent signs that Legionella exists in your pool. By the time you suspect Legionella, it’s probably dead.

How can you test for it? This form of the bacteria is detectable only with a direct fluorescent antibody (DFA) test, which is both expensive and time consuming. State and private laboratories can perform this test.

If present, how do you remove it from the pool water? Legionella is easy to kill: finding it is the hard part. Be sure to test sample from you filter media, filter tanks and plumbing. Superchlorination will eradicate Legionella from your water, but you’ll have to disinfect your filters. You may need to drain and disinfect your pool or spa.


Contributors

Peter Andreotti, Ph.D., ASD Laboratories, Boca Raton, Fla.; Centers for Disease Control, Atlanta; Alison Osinski, Ph.D., Aquatic Consulting Services, San Diego; RGF O3 Systems, Inc., West Palm Beach, Fla.; Joe Sweazy, Environmental Test Systems, Elkhart, Ind.; Culin Tate, Chemical Automation Technologies Inc., Gaithersburg, Md.; and Rich Young, Aquatic Commercial Consulting, Saratoga, Calif.


For more information regarding waterborne diseases or other important aquatic issues, click here or contact us at 1-844-482-1777.