Over the 4th of July holiday, many Americans will get together for picnics, barbeques, and other gatherings. For many, food will take center stage, and hopefully proper food safety practices will ensure that in the days following these gatherings people will not be doubled-over in pain, running to and from the bathroom because of something they ate. The FDA has published recommendations for keeping food safe when eating outdoors that could be useful in helping prevent foodborne illness among your friends and family.
For some, water – not drinking water – will take center stage. And water sources can contain some of the same pathogens as food sources. Pools, recreational water, and even municipal water sources have been pinpointed as the source of E. coli, cryptosporidium, Salmonella, and other outbreaks in recent years. (See Cryptosporidiosis: A Recreational Water Threat That Hasn’t Gone Away)
Water sources can become contaminated with E. coli and other pathogens in a variety of ways. Water that is downstream from cattle pastures, feed lots, or barns can easily become contaminated with pathogens from runoff. When lakes become contaminated, several weeks or months can pass before water quality conditions improve or return to normal.
Pools can become contaminated with E. coli by animal feces or through fecal contamination from an infected person. Children who are not yet toilet trained and soil diapers while playing in water have been identified as the source of several outbreaks. Proper chlorine levels must be maintained to prevent the spread of E. coli in pools and at water parks.
In 1998, an E. coli O157:H7 outbreak was traced to an infected toddler who played in a pool at the White Water Water Park outside Atlanta, Georgia. Although the pool was chlorinated, the chlorine concentration and contact time was presumably insufficient to kill the E. coli resulting from fecal contamination by the toddler, and other children who were in the pool ingested E. coli bacteria while playing in the pool. Twenty-six culture-confirmed E. coli cases were identified during the outbreak, and 40 percent of children under five years of age with recognized E. coli infections were diagnosed with hemolytic uremic syndrome (HUS).
In 2005, thousands of people fell ill with cryptosporidiosis, a gastrointestinal illness that causes diarrhea and vomiting, after visiting the spraypark at the Seneca Lake State Park in New York State. By the time the public health investigation had concluded, at least 3,900 people in New York had reported becoming ill with cryptosporidiosis after taking part in recreational activities at the spraypark, which is located near Geneva. Cryptosporidium was found in two water storage tanks that supplied the 11,000-square-foot spraypark. Since that time, the spraypark has undergone a renovation for its water storage devices.
When municipal water sources become contaminated, systems must be flushed to ensure all bacteria has been eliminated from the system, and chlorine levels high enough to kill any bacteria, parasites, or viruses must be introduced.
In 2008, the Colorado Department of Public Health and Environment (CDPHE) reported that 417 people became ill with Salmonella after drinking water from the Alamosa municipal water system, and one resident died. The Centers for Disease Control and Prevention (CDC) and CDPHE confirmed the presence of Salmonella in five out of six water samples taken from various areas around Alamosa, and laboratory results confirmed the presence of Salmonella in the water system, which was flushed in a three-stage water treatment process beginning March 25.