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Do You Know What’s in the Water?—Commentary

08/08/16 Larry M. Bush, MD, FACP, Charles E. Schmidt College of Medicine, Florida Atlantic University|University of Miami-Miller School of Medicine;

Preventing Waterborne Illnesses

With the summer Olympics underway, all eyes are on Rio de Janeiro. But the city and Olympic organizers have drawn unwanted attention for unsanitary conditions in waterways where rowers, sailors, and windsurfers will compete. The city struggled to treat much of the water, which is contaminated with raw sewage and trash, leading athletes to bleach their equipment and use antibacterial mouthwash between events.

Everyone from the World Health Organization to ESPN has questioned the safety of Rio’s water, leading to an increased focus on water safety around the world. In the U.S., water-bound families generally don’t worry about water safety when heading to beaches, lakes, and pools.

But that doesn’t mean you shouldn’t be aware of the waterborne illnesses that may be lurking the in water. Here are five waterborne illnesses to be aware of when your family’s headed for the pool, beach, lakes, or streams.

1. Giardiasis: Giardiasis is an infection of the small intestine caused by the parasite Giardia, which lives in fresh water. It’s the most common parasitic intestinal infection in the United States. It is sometimes known as beaver fever because it is commonly transmitted through the feces of beavers and other animals infected with Giardia. Giardia can be present even in clean-appearing mountain streams, so hikers are at risk.

Symptoms typically appear one or two weeks after infection and include abdominal cramps, gas, and watery, foul-smelling diarrhea. If you think you or a family member has giardiasis, make an appointment with a doctor, who will likely ask you for a stool sample. Treatment typically involves a course of antiparasitic drugs.

2. Shigellosis: Shigellosis is an infection caused by the bacteria Shigella. An estimated 500,000 people in the U.S. develop the infection every year due to water contaminated with human waste and inadequately chlorinated pools. It’s especially common in children and can spread quickly at daycare centers and pools. Individuals don’t have to ingest very much water contaminated with Shigella to become infected.

Symptoms include fever and diarrhea along with painful abdominal cramps. More severe infections may lead to dysentery—frequent bowel movements that may contain blood, mucus, and pus. Treatment for shigellosis includes fluids with salt and antibiotics for more severe cases.

3. Vibriosis: Vibriosis is an infection caused by about a dozen Vibrio bacteria. Cholera is the most serious illness caused by the bacteria, but cholera is not very common in the U.S. Vibrio bacteria that do not cause cholera live in warm salt water or mixed salt and fresh water (like bays). Most noncholera vibrio infections are intestinal infections caused by consuming inadequately cooked shellfish (especially oysters) harvested from contaminated waters. People can also develop Vibrio skin infections if they have an open cut and swim in contaminated water or cut themselves by stepping on a crustacean that harbors Vibrio. Vibrio vulnificus, which thrives in warmer water temperatures, was responsible for a number of deaths and amputations along the Gulf Coast this year.

Vibriosis causes 80,000 illnesses each year in the United States, according to the Centers for Disease Control and Prevention (CDC). Symptoms include diarrhea, cramping, nausea, vomiting, fever, and chills. Treatment is limited to drinking lots of water to replace lost fluids.

4. Escherichia coli (E. coli) infection: E. coli bacteria normally reside in the intestine of healthy people, but some strains can cause infection. At least 100 strains can cause infection, and E. coli O157:H7 is the most common. It can be contracted by swallowing inadequately chlorinated water that’s been contaminated by the stool of infected individuals, for example in public pools. Lakes and beaches occasionally close due to E.coli outbreaks.

Symptoms, primarily diarrhea and cramps, begin about three days after exposure. For E. coli 0157:H7, treatment is usually limited to giving fluids, and symptoms typically resolve within eight days.

5. Primary amebic meningoencephalitis (PAM): PAM is an infection of the brain caused by the Naegleria fowleri amoeba. The amoeba lives in warm fresh water throughout the world and enters the brain by traveling up nerves from the nose. Although PAM is rare (only 138 people have died from it since 1962, according to the CDC), it made headlines recently when an 18-year-old woman was killed by the “brain-eating amoeba” after contracting it on a whitewater rafting trip.

When the amoeba reaches the brain, it causes inflammation, tissue death, and bleeding. Symptoms, which appear within one to two weeks, include a change in smell or taste, headache, stiff neck, sensitivity to light, nausea, and vomiting. The infection moves fast, often causing death within 10 days.

Keys to prevention

The most effective prevention strategies go hand in hand with good overall health: make sure all vaccinations are up to date, drink only properly treated water, and practice good personal hygiene. But there are more specific steps you can take before, during, and after you or your family goes in the water to limit the risk.

Before you go in the water:

  • Check for official updates on the condition of the water and advisories warning people not to swim.
  • Inspect the water for signs of bacteria or algae, which can cause skin irritation.
  • Look for other bathers who may be unsanitary, and avoid swimming in water where babies are wearing diapers or people have open cuts.
  • Shower to wash away any bacteria on you.

During your time in the water:

  • Avoid swimming with open cuts because even waterproof bandages do little to prevent bacteria entering a wound.
  • Try to swallow as little water as possible.

It is all right to open your eyes when you're under water because eyes are mostly impervious to bacteria in the water.

After you get out of the water:

  • Take a thorough shower immediately.
  • If you do contract an illness, alert the pool, township, park, etc. as quickly as possible with as many details as possible.