Waterborne Illnesses

Sheryl Schumacher
Ravalli County Public Health
205 Bedford, Suite L
Hamilton, Montana

Waterborne Illnesses... come from a variety of potential sources; swimming pools, lakes, rivers, oceans and even spas are all culprits. Ingesting natural or recreational water and untreated drinking water can have an adverse effect on a person's stomach and intestines, skin, or respiratory system. In some instances dermal contact, which is contact of the water with skin or mucous membranes, or by inhaling mist or aerosolized water particles can result in allergic reactions.

Waterborne Disease Outbreaks...are caused by infectious agents including viruses, bacteria, and parasites. Testing private wells at least every 3 years and after potential contamination such as after floods is recommended.

Stomach and Intestinal Illness
On average, there are more than 100 cases of crypto and giardia reported in Montana every year. More than half of these reported cases, were people swimming in the days before they became ill.

The following gastrointestinal illnesses have been associated with recreational water activities and can cause diarrhea, nausea and or vomiting.

Cryptosporidium (Crypto) has become one of the most common causes of waterborne diseases in humans in the United States during the past 2 decades. It is a parasite typically associated with animals and humans and can be acquired through the consumption of food contaminated by feces. It is highly resistant to chlorine disinfection because it's protected by an outer shell that allows for survival outside the body for long periods of time. Swallowing contaminated water is another source of infection.

Cryptosporidium can be prevented through thorough hand washing, boiling water for one minute, washing and or cooking fruits and vegetables. If you travel to developing nations you may be at a greater risk for crypto. Opt for steaming-hot foods, fruits that you can peel, bottled and canned drinks, and hot coffee and tea are probably safe. Avoid raw fruits and vegetables, tap water or ice made from tap water, unpasteurized milk or dairy products, and items purchased from street vendors. These items may be contaminated with crypto. Talk with your health care provider about other guidelines for travel abroad.

Giardia is a parasite and another common cause of diarrhea that is found in infected people's stool. It can take about 45 minutes for this germ to be killed by chlorine disinfection in pools. Keep your mouth closed. Avoid swallowing water while swimming in pools, lakes, streams or other open bodies of water. Typically associated with water giardia can also be found in soil and food. No drug or vaccine can prevent giardia infection. However, common-sense precautions can go a long way toward reducing the chances of infection or spreading the infection to others. Remember thorough hand washing, avoid drinking untreated water from shallow wells, lakes, rivers, springs, ponds and streams unless you filter it or boil it for at least 10 minutes at 158 F (70 C) first. If you're traveling to underdeveloped countries drink and brush your teeth with bottled water, don't use ice and avoid raw fruits and vegetables.

Schistosomatidae or Swimmer's itch, also called cercarial dermatitis, appears as a skin rash caused by an allergic reaction to certain parasites. These microscopic parasites are released from infected snails into fresh and salt water (such as lakes, ponds, and oceans). While the parasite's preferred host is the specific bird or mammal, if the parasite comes into contact with a swimmer, it burrows into the skin causing an allergic reaction and rash. Swimmer's itch is found throughout the world and is more frequent during summer months. The rash can't be spread from person to person. Symptoms often include a rash with a possible itching or burning sensation on your skin. Pimples may appear several hours after exposure to the water and they may later turn into blisters. These symptoms usually resolve and disappear in about a week. Most cases of swimmer's itch do not require medical attention. Cool wet compresses, calamine lotion, or other over-the-counter anti-itch creams may help relieve the itching.

Campylobacter is a bacteria primarily associated with poultry, animals, and humans. The most common way to get it is by eating contaminated food, especially improperly cooked poultry, or by drinking raw (unpasteurized) milk. Campylobacter can be spread from person to person by the fecal-oral route. Symptoms of diarrhea usually develop between 1 and 7 days of being exposed.

Norovirus is very contagious and can spread through an infected person's stool or vomit. The illness often begins suddenly and usually includes nausea, vomiting, diarrhea, and stomach cramps. Chlorine disinfection helps kill this virus in pools, but lakes and beaches can be contaminated. Usually resolved in a day or two, most cases don't require extraordinary measures. Norovirus can't be treated with antibiotics because it is a viral infection. Only bacterial infections are treated with antibiotics. Consuming fluids like sports drinks and water will help in maintaining proper hydration levels, which is crucial to avoid and hospitalization for dehydration.

Healthful Tips: If you have diarrhea stay out of the water. Keep your mouth closed and don't swallow the water. Remember thorough hand-washing, boiling water for one minute and washing your fruits and vegetables.

Contact your health care provider if you suspect you have a recreational or waterborne illness that needs medical attention.

Pool rules



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