$Unique_ID{BRK03770} $Pretitle{} $Title{Giardiasis} $Subject{Giardiasis Lambliasis Beaver Fever Amebiasis Hookworms Threadworm (Strongyloidiasis)} $Volume{} $Log{} Copyright (C) 1987, 1989 National Organization for Rare Disorders, Inc. 492: Giardiasis ** IMPORTANT ** It is possible the main title of the article (Giardiasis) is not the name you expected. Please check the SYNONYMS listing on the next page to find alternate names, disorder subdivisions, and related disorders covered by this article. Synonyms Lambliasis Beaver Fever Information on the following diseases can be found in the Related Disorders section of this report: Amebiasis Hookworms Threadworm (Strongyloidiasis) General Discussion ** REMINDER ** The information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Giardiasis is an infectious disorder of the gastrointestinal tract caused by a genus of protozoan parasite known as Giardia lamblia. This disorder may not cause noticeable symptoms, but when many of these parasites are present, absorption of nutrients is diminished. Additionally, acute gastrointestinal discomfort, chronic or acute diarrhea, and other digestive system abnormalities can occur. This disorder has occurred in epidemics associated with contaminated water in which infected beavers live because parasites in the cyst stage from beavers are infectious to humans. These cysts can survive in cold water for several months. Symptoms Giardiasis may not cause symptoms if a patient has ingested only a few protozoan parasites known as Giardia lamblia. When there is an initial concentration of many parasites in the intestines, acute abdominal discomfort, diarrhea, excessive gas (flatulence), and foul-smelling stools may result. When recurrent unexplained abdominal discomfort develops along with these symptoms, Giardia parasites may be lodged in the duodenum. Acute attacks usually last approximately three or four days, although symptoms may persist for several weeks. Infection may resolve spontaneously in some patients, but treatment is usually required. In long-term infestation, patients may experience chronic diarrhea, malabsorption of nutrients, weight loss, upper abdominal (epigastric) cramping, loss of appetite (anorexia), nausea, vomiting, and/or excretion of fat in the stools. The disease affects only the intestines. Causes Giardiasis is caused by the protozoan parasite known as Giardia lamblia. Humans are infected by the parasites in the cyst stage (e.g., when they are excreted by beavers. After beavers have contaminated the water supply in which they live, cysts often exist for several months, even in cold water. Person-to-person (fecal-oral or sexual contact) and foodborne cases also occur. Giardiasis has also been known to be transferred to humans by dogs and other animals. Affected Population Giardiasis affects persons coming in contact with the protozoan parasite known as Giardia lamblia. This disorder occurs worldwide. Epidemics have occurred in the United States when parasitic cysts are excreted by beavers in public water reservoirs. Epidemics have also occurred in day care centers and custodial institutions such as prisons and long-term care facilities. Related Disorders Symptoms of the following disorders can be similar to those of Giardiasis. Comparisons may be useful for a differential diagnosis: Amebiasis is a disease of the intestinal tract caused by the protozoan parasite, Entamoeba histolytica. The infection is spread person-to-person or indirectly via contaminated food or water. The organism invades the colon and rectum and produces ulcers and inflammation. Symptoms begin gradually with an increasing number of stools reaching as many as fifteen per day. Stools may be semi-solid to liquid and they often carry blood. Fever, local bowel tenderness and cramping abdominal pain occur. If the liver is affected, tenderness will develop in that area. In the United States, Amebiasis primarily affects visitors returning from countries with poor sanitation. Treatment with the drug metronidazole (Flagyl) is often effective in eliminating the disorder. Hookworms are a parasitic organism which penetrate the skin and migrate to the intestines where they attach themselves by their mouth and suck blood. Abdominal pain is the most common symptom, but an asymptomatic anemia which can limit growth in children may also occur. Approximately twenty-five percent of the world population may be infected with hookworms. Parasites attach themselves to a person walking barefoot in soil contaminated with hookworm larvae. Several effective drugs are available for treatment. Threadworm (Strongyloidiasis) is a parasitic intestinal disorder characterized by upper abdominal (epigastric) pain and tenderness, vomiting, and diarrhea. This disorder is usually found in the tropics in areas of poor sanitation. It can exist in crowded and unsanitary institutions anywhere. Threadworm can persist for decades. Treatment with the drug thiabendazole is often effective for Threadworm patients. Therapies: Standard The treatment of choice for Giardiasis patients is the drug quinacrine. Mild cases may respond to the drug furazolidone (Furoxone). The most important factor for preventing this disorder is proper treatment of infected water. Chlorination may not kill cysts; sedimentation, flocculation and filtration should also be performed. Water can be boiled for one minute, or mixed with halazone or iodine to eliminate contamination. Travelers to areas with contaminated water should drink only boiled or treated water and should not consume uncooked fruit or vegetables. Therapies: Investigational Treatment with the drugs tinidazole, ornidazole or metronidazole for Giardiasis may be effective. However, these medications have not yet been approved for use in the United States for this condition. This disease entry is based upon medical information available through September 1989. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder. Resources For more information on Giardiasis, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 NIH/National Institute of Allergy and Infections Diseases (NIAID) 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5717 Centers for Disease Control (CDC) 1600 Clifton Road, NE Atlanta, GA 30333 (404) 639-3534 References INTERNAL MEDICINE, 2nd ed.: Jay H. Stein, ed.-in-chief; Little, Brown and Co., 1987. Pp. 1785-1786. MANAGEMENT OF GIARDIASIS: E.D. Gorski; Am Fam Physician (November 1985, issue 32(5)). Pp. 157-164. SELECTIVE PRIMARY HEALTH CARE: STRATEGIES FOR CONTROL OF DISEASE IN THE DEVELOPING WORLD. XIX. GIARDIASIS: D.P. Stevens; Rev Infect Dis (July 1985, issue 7(4)). Pp. 530-535. TREATMENT OF INTESTINAL E. HISTOLYTICA AND G. LAMBLIA WITH METRONIDAZOLE, TINIDAZOLE AND ORNIDAZOLE: A COMPARATIVE STUDY: S. Bassily, et al.; J Trop Med Hyg (February 1987, issue 90 (1)). Pp. 9-12.