An outbreak of a parasitic disease that causes pool-related diarrhea has spread across Northern Kentucky.
The Northern Kentucky Department of Health has confirmed about a dozen cases of cryptosporidiosis in the region, with many of the confirmed cases having visited swimming pools in the area.
The parasite that causes cryptosporidiosis is highly resistant to chlorine, an essential ingredient in keeping swimming pools clean. The normal concentrations of chemicals in pools do not kill the parasite.
The source of the infestation is still unknown, but Silver Lake, a family recreation center in Erlanger, Kentucky, that features a pool and water slides, was forced to close in order to increase chlorine levels to kill any remaining parasites.
Silver Lake, a family pool and fitness club in Erlanger, Kentucky, recently reopened after stepping up chlorination of its pool to kill the cryptoparasite that makes people sick.
People infected with the parasite shed infectious spores in their faeces.
Some people can become ill by accidentally touching or swallowing infected feces.
Once ingested, these spores travel to the small intestine, where they invade intestinal cells and produce more spores.
As the parasitic cells multiply, they damage the intestinal wall, causing symptoms such as watery diarrhea, abdominal pain, nausea, and slight fever.
This infection is usually self-limited, meaning it will go away on its own without treatment. The infection usually lasts for about 2 weeks.
Unless your defenses are particularly weak, your body’s immune system will attack the parasites and limit their ability to reproduce in your digestive tract.
This puts children and older people, who tend to have weaker immune systems, at particular risk of developing a severe illness that can last for several weeks.
Steve Devine, environmental health and safety director for the Northern Kentucky Department of Health, said pools need to be “over-chlorinated” to kill the harmful parasites, “which requires much higher chlorine concentrations than you would normally use in day-to-day operations.”
“We need to wait for the water levels to drop for a period of time and then for the water levels to return to normal ranges before people can swim again.”
When health officials learned that about half of the Cryptospolis cases could be traced to Silver Lake, the city did just that.
The club issued a statement assuring them that the chlorine levels in the pool were far in excess of what would be needed to kill cryptosporin.
“Once this process was complete and chlorine levels returned to safe levels, the health department gave the go-ahead to reopen the pool. This process took more than 42 hours to complete.”
The source of infection is unknown, but about half of the infected people are believed to have visited Silver Lake. Health officials expect the current number of infected people to increase in the future.
Although summer fun has resumed in Silver Lake, Devine is confident the spread won’t end there: “We have at least 12 lab-confirmed cases, and this number will grow.”
No matter how diligently authorities monitor chlorine levels, infections can spread quickly in swimming pools.
A typical swimming pool has 1 to 3 ppm of chlorine, which is not enough to kill pathogens, which can survive in the pool for about a week, depending on the water temperature.
Infected individuals can shed millions of cryptospores in their stool, and even small amounts can be ingested in the stool, causing widespread disease.
To kill the parasites, the chlorine concentration must be increased to about 20 ppm and maintained at that level for about 13 hours.
Apart from swimming pools, childcare facilities are a hotbed of infection, accounting for 13% of cases.
“At the moment I’m not just worried about the pool, I’m worried about the nurseries, and now that schools are back in session I’m worried about the daycares,” Devine said.
The CDC recommends that pool users shower before and after bathing, take children to the bathroom regularly and wash their hands thoroughly, do not allow children to swim if they have recently had diarrhea, and always change babies’ diapers in the bathroom – never poolside.
“When a child is actively moving in the water and keeping their head submerged, it’s hard for them to keep from swallowing water,” said Dr. Joseph Eisenberg, chair of the epidemiology department at the University of Michigan School of Public Health.
“Parents can be proactive by making sure their swimming facility is properly managing risks in their pools.”
And if you do get an infection, remember to stay hydrated, Dr. Eisenberg said.
“This is especially true for children with diarrhea. Fluid loss can lead to more serious illness, and IV hydration is something we should all avoid.”
