The 18-year-old Ohio woman died of primary amebic mengioencephalitis on Sunday, a rare but fatal brain infection caused by the amoeba Naegleria fowleri, said Mitzi Kline, director of communication for Franklin County Public Health. The Centers for Disease Control and Prevention confirmed the presence of the amoeba in cerebral spinal fluid.
The amoeba is commonly found in warm freshwater and soil, according to the CDC
. It also grows in pipes but not salt water such as oceans.
The teen's "only known underwater exposure was believed to be when riding in a raft with several others that overturned at the U.S. National Whitewater Center in Charlotte," the North Carolina Department of Health and Human Services said
In response to the incident, the U.S. National Whitewater Center said in a statement
that it gets its water from the Charlotte-Mecklenburg Utilities Department and two wells on its property, adding that it disinfects all water with ultraviolet radiation and chlorine. "The levels of UV radiation disinfection utilized every day, continuously, at the Center are sufficient to 'inactivate' the water born amoeba in question to an effective level of 99.99%," the statement said. Out of an abundance of caution, it said it added more chlorine into its system when it learned of this incident.
State and county health officials are working with the CDC and the water park to investigate the death. CDC personnel are in North Carolina and hope to take samples of the water as part of the investigation.
What is Naegleria fowleri?
A person will not become ill from drinking contaminated water, but when water with Naegleria fowleri enters the body through the nose and travels to the brain, the consequence is almost always deadly. This can result from diving into the water or entering the water from a water slide. There have also been cases linked to improperly disinfected swimming pool water or heated and contaminated tap water. However, most infections were the result of swimming in warm lakes or rivers. Naegleria fowleri infections most often occur in summer months and in Southern states, and they are not contagious.
Symptoms, which include headache, fever, nausea and vomiting, usually begin about five days after infection but can occur within one to nine days. The illness often causes death within five days of when symptoms begin.
Kline noted that Naegleria fowleri infections are rare. The CDC reported
37 infections in the 10 years from 2006 to 2015. But the fatality rate of the infection is as high as 97%. "Only 3 out of the 138
known infected individuals in the United States from 1962 to 2015 have survived," the CDC said.
How to prevent Naegleria flowleri infections
To limit the risk of infection, North Carolina health officials recommended the following precautions:
- Limit the amount of water going up your nose. Hold your nose shut, use nose clips or keep your head above water when taking part in warm freshwater-related activities.
- Avoid water-related activities in warm freshwater during periods of high water temperature and low water levels.
- Avoid digging in, or stirring up, the sediment while taking part in water-related activities in shallow, warm freshwater areas.