In recognition of Discovery Channel launching its annual "Shark Week" programming on July 23, STAT published a list of waterborne pathogens more likely to harm summertime swimmers than sharks.
Here are seven waterborne pathogens to know.
1. Cryptosporidium: This diarrhea-inducing parasite is often transmitted via swimming pools and water playgrounds. Outbreaks attributed to this parasite more than doubled in the U.S. from 14 in 2014 to 32 in 2016.
2. Pseudomonas: These rod-shaped bacteria commonly infect hot tub users by burrowing into hair follicles, subsequently causing red, itchy bumps on the skin.
3. Shigella: These highly contagious bacteria can dwell in lakes, ponds and beaches and cause approximately 500,000 illnesses in the U.S. annually. Swallowing contaminated water can bring on shigellosis — a gastrointestinal illness characterized by mild to severe diarrhea that can also include symptoms like fever, nausea, vomiting, cramps and bloody stools.
4. Legionella: These bacteria infect the airways, not the gut, and can be transmitted by the warm, steamy air of hot tubs. The bacteria induce a virulent form of pneumonia called Legionnaires' disease.
5. Norovirus: Symptoms attributable to norovirus include stomach pain, fever, vomiting and diarrhea. The virus can spread via contact with the fecal matter of infected people, which can contaminate surfaces, food and water. On average, the illness causes 56,000 to 71,000 hospitalizations and 570 to 800 deaths each year, according to the CDC.
6. Cyanobacteria: These bacteria thrive in the summertime. When runoff fertilizer is introduced to beaches, lakes and rivers, explosive bacterial growth can occur. The bacterial blooms are toxic and can irritate the eyes, skin and throats of swimmers. Swallowing water containing the bacteria can induce headaches, vomiting and even liver damage in severe cases.
7. Naegleria fowleri: This parasite is commonly referred to as the "brain-eating" amoeba and is native to warm freshwater. When the amoeba enters the body through the nose, the brain infection primary amebic meningoencephalitis can occur. The illness is rare, but almost always fatal. There were 138 cases of PAM in the United States between 1962 and 2015. Of those cases, just three survived, according to the CDC.
More articles on infection control:
Hawaii mumps outbreak tops 170
Drug mixture boosts survival rate for HIV patients, study finds
Top 10 infection control stories, July 17-21