Waterborne diseases, caused by harmful bacteria, viruses, and parasites in contaminated water, are a major global health concern. They are especially common in areas with poor sanitation and limited access to clean drinking water. Contamination can occur in natural sources like lakes, rivers, and wells, as well as in improperly treated municipal water supplies, spreading infections through drinking, bathing, or food preparation.
Below, are the ten of the most common waterborne diseases, their causes, symptoms, and the best methods for purifying water to reduce the risk of infection.
Cholera is a severe diarrheal illness caused by the bacterium Vibrio cholerae. It thrives in areas with inadequate sanitation and contaminated water, often spreading rapidly during natural disasters when sewage mixes with drinking water sources. The bacteria produce a toxin in the intestines, leading to severe watery diarrhea, dehydration, nausea, vomiting, and muscle cramps. Without prompt treatment, dehydration can become life-threatening. To prevent cholera, it’s essential to boil water for at least one minute or use chlorine or iodine tablets, along with maintaining proper hand hygiene and sanitation practices.
Typhoid fever is a bacterial infection caused by Salmonella typhi, which spreads through contaminated food and water. It is particularly common in developing countries with poor sanitation and unsafe water supplies. Symptoms include prolonged high fever, weakness, stomach pain, loss of appetite, constipation, or diarrhea. If untreated, the bacteria can spread through the bloodstream, affecting multiple organs. To reduce the risk of typhoid fever, drink only purified water, wash hands thoroughly before eating, avoid raw foods in high-risk areas, and consider vaccination if traveling to endemic regions.
Giardiasis, often referred to as "beaver fever," is a parasitic infection caused by Giardia lamblia. The parasite is commonly found in streams, rivers, lakes, untreated municipal water supplies, and contaminated recreational waters. Symptoms include bloating, gas, diarrhea, nausea, and weight loss, and the infection can persist for weeks without treatment. To prevent giardiasis, use high-quality water filters, boil water, or use iodine-based disinfectants. Avoid drinking from untreated natural water sources to minimize the risk of infection.
Dysentery is a severe intestinal infection caused by bacteria or parasites, leading to inflammation of the colon and severe diarrhea. It is often associated with contaminated food and water, particularly in overcrowded and unsanitary living conditions. Symptoms include blood or mucus in the stool, stomach cramps, fever, and dehydration. If left untreated, dysentery can cause severe complications such as malnutrition and organ failure. To prevent it, drink boiled or properly filtered water, wash hands regularly, and avoid consuming raw or unclean foods.
Hepatitis A is a viral infection that affects the liver and is caused by the Hepatitis A virus (HAV). It spreads primarily through contaminated water and food, especially in areas with inadequate sanitation and poor hygiene practices. Symptoms include jaundice (yellowing of the skin and eyes), fatigue, nausea, vomiting, dark urine, and abdominal pain. While most cases resolve on their own, severe infections may require hospitalization. To prevent Hepatitis A, drink only boiled or bottled water, practice good hygiene, and consider vaccination if traveling to high-risk areas.
Cryptosporidiosis is a parasitic infection caused by Cryptosporidium, known for its high resistance to chlorine and many types of purifying tablets. It is commonly found in lakes, rivers, swimming pools, and improperly treated municipal water supplies. Symptoms include watery diarrhea, stomach cramps, dehydration, nausea, and weight loss. The infection is particularly dangerous for individuals with weakened immune systems. To protect against cryptosporidiosis, use water filtration systems or boil water, as traditional chlorination methods may not effectively eliminate the parasite.
Legionnaires’ disease is a severe form of pneumonia caused by Legionella bacteria, which thrive in warm, stagnant water. Common sources include hot tubs, cooling towers, air conditioning systems, and plumbing systems in large buildings. Symptoms include fever, chills, cough, muscle aches, and difficulty breathing. Without treatment, the disease can be fatal. To prevent Legionnaires’ disease, ensure regular maintenance and cleaning of water systems, especially in large buildings and healthcare facilities, to reduce bacterial growth.
Polio is a highly contagious viral disease that can cause paralysis and even death. It spreads primarily through contaminated water and poor sanitation, particularly in areas with low vaccination rates. Symptoms include fever, fatigue, stiffness in the neck, and, in severe cases, paralysis. Some individuals may be asymptomatic but still spread the virus. To prevent polio, ensure access to safe drinking water and maintain high vaccination coverage in communities to stop the spread of the virus.
Leptospirosis is a bacterial infection transmitted through water contaminated with animal urine, particularly from rodents. It is commonly found in floodwaters, lakes, and streams, especially after heavy rainfall or natural disasters. Symptoms include high fever, chills, muscle aches, vomiting, and, in severe cases, kidney or liver damage. Without antibiotics, the disease can be fatal. To prevent leptospirosis, avoid contact with floodwaters, wear protective clothing, drink treated water, and take precautions in areas with a high risk of rodent infestation.
E. coli infection is caused by the bacterium Escherichia coli, often linked to contaminated food and water. It is commonly found in untreated water sources, undercooked food, and unpasteurized dairy products. Symptoms include severe stomach cramps, diarrhea (sometimes bloody), vomiting, and fever. Some strains can lead to kidney failure. To reduce the risk of E. coli infection, boil or filter water, cook food thoroughly, and avoid consuming raw dairy products.
To minimize the risk of waterborne illnesses, use these effective water purification methods: