Nasty Infectious Diseases You Want To Avoid - Giardiasis
This is the most common cause of water borne intestinal infection in the United States. Giardiasis is an infection of the small intestine caused by the Giardia lamblia protozoa, which is found in the human intestinal tract and in feces. In recent years, outbreaks of giardiasis have been common among people in institutions, preschool children, at catered affairs, and large public picnic areas. Recent tests have revealed the parasite in approximately seven percent of all stool samples tested in a nationwide study.
Cause - Giardiasis is spread by contaminated food or water or by direct personal hand-to-mouth contact. Children can spread the infection by touching contaminated toys, changing tables, utensils, or their own feces. For this reason, the infection spreads quickly through a day care center or institution for the developmentally disabled. Unfiltered streams or lakes that may be contaminated by human or animal feces are a common source of infection to campers, thus Giardiasis does present itself in higher levels within the population of people who spend a lot of time outdoors.
Symptoms - Giardiasis is not fatal, and about two thirds of infected people have no symptoms. When they do occur, symptoms appear about one to three days after infection and are uncomfortable. The infection interferes with the body's ability to absorb fats in the intestinal tract, so the stool is filled with fat. Symptoms include explosive diarrhea, foul-smelling and greasy feces, stomach pains, gas, loss of appetite, nausea, and vomiting. In some cases, the infection can become chronic.
Diagnosis - Giardiasis is diagnosed by examining three stool samples for the presence of the parasites. Because the parasite is shed intermittently, half of the infections will be missed if only one specimen gets checked. Stool collection kits are available for this purpose. A different test looks for the proteins of Giardia in the stool sample.
Treatment - Acute giardiasis usually runs its course and then clears up, but antibiotics will help relieve symptoms and prevent the spread of infection. Medications include metronidazole, furazolidone, and paromomycin. Occasionally, treatment fails; in this case, the patient should wait two weeks and repeat the medication. Anyone with an impaired immune system may need to combine medications. Healthy carriers do not need to be treated.
Complications - Some children get chronic infection and suffer with diarrhea and cramps for long periods of time, losing weight and growing poorly. Those most at risk for an infection are people with impaired immune function, malnourished children, people with low stomach acid, and older people.
Prevention - The best way to avoid giardiasis is to stay away from drinking untreated surface water. While chlorine in water treatment will not kill the cysts, filtered public water supplies eliminate it. Also, maintain good personal hygiene; don't eat unwashed fruit or vegetables unless they can be peeled; boil water if in doubt and campers especially should boil stream water for three minutes before drinking; if an outbreak occurs in a child care center, the director should notify the local health department. Children with severe diarrhea must stay at home until the stool returns to normal.