Contaminated Water

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Leptospirosis, an infection caused by bacteria called Leptospira, is an infectious disease spread by contaminated water and soil. It is a zoonotic infection, which means it spreads from animals to people. Many mammals may carry it however the most common source of human infection is rats. Leptospirosis causes disease in humans around the world, especially in warmer climates and developing countries with poor housing and sanitation. It is also seen in developed countries in outdoor athletes (like triathletes) and enthusiasts, after severe floods, and in certain occupations like farmers, including dairy farmers, sewer workers, slaughterhouse workers, fish workers (freshwater fish only), veterinarians and animal caretakers, and the military. Recently, rising rates of infections have been seen in inner-city children. children. Person-to-person transmission is rare.

Leptospirosis is one of many diseases that can be caused by contaminated fresh water (Leptospira cannot survive in saltwater) and contaminated soil. The bacteria are found in animal urine and other body fluids except saliva. It may survive for months in soil. Humans are infected by contact with contaminated soil or water, including drinking contaminated water. It enters humans via mucous membranes (nose, mouth, and eyes) and open cuts or sores. The incubation period, or time between contact and symptoms, may be two days to four weeks. Symptoms in the primary stage of the disease are flu-like and include high fever, headache, muscle aches, chills, abdominal pain, nausea and vomiting, diarrhea, rash, red eyes, and jaundice (yellowing of the skin and eyes). The first phase may last a few days to weeks, and if untreated, a few months. After recovery from the initial stage, about 10 percent of people develop a second stage which may cause severe disease including kidney failure, respiratory failure, meningitis, liver failure, and death. The death rate for severe disease is five to 15 percent. The most severe form of leptospirosis is called Weil's disease.

The disease may be diagnosed by a blood test to detect antibodies in the blood. It may be treated with antibiotics like penicillins, tetracyclines, or azithromycin. Mild cases often do not require treatment. Severe cases often require hospitalization and support in the intensive care unit. Those at the highest risk to develop Leptospirosis include people who live in poor housing with poor sanitation, people who wade through floodwaters (not Sandy, freshwater only), people who swim in lakes and rivers, kayakers, whitewater rafters, adventure racers, triathletes, hikers and campers, people in occupations such as veterinarian medicine, agriculture, mining, plumbing, and garbage collection, and international travelers.

Tips to prevent infection include avoid water or mud that may be contaminated with animal urine, look for posted signs when participating in freshwater sports, avoid swallowing lake or river water, cover cuts or scrapes before submerging in outdoor freshwater, avoid wading in freshwater floods, wash cuts and scrapes, and shower after possible exposure, and wear protective shoes and clothing. There is no vaccine for Leptospirosis.

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