Cryptosporidiosis: Intestinal infection with organisms of the genus CRYPTOSPORIDIUM. It occurs in both animals and humans. Symptoms include severe DIARRHEA.Chaperonins: A family of multisubunit protein complexes that form into large cylindrical structures which bind to and encapsulate non-native proteins. Chaperonins utilize the energy of ATP hydrolysis to enhance the efficiency of PROTEIN FOLDING reactions and thereby help proteins reach their functional conformation. The family of chaperonins is split into GROUP I CHAPERONINS, and GROUP II CHAPERONINS, with each group having its own repertoire of protein subunits and subcellular preferences.Characeae: Family of slender threadlike aquatic plants, in the order CHARALES, phylum STREPTOPHYTA, that are closely related to LAND PLANTS.Coccidia: A subclass of protozoans commonly parasitic in the epithelial cells of the intestinal tract but also found in the liver and other organs. Its organisms are found in both vertebrates and higher invertebrates and comprise two orders: EIMERIIDA and EUCOCCIDIIDA.Swimming PoolsChemokine CXCL13: A CXC chemokine that is chemotactic for B-LYMPHOCYTES. It has specificity for CXCR5 RECEPTORS.Water Supply: Means or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)Feces: Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.Pacific Islands: The islands of the Pacific Ocean divided into MICRONESIA; MELANESIA; and POLYNESIA (including NEW ZEALAND). The collective name Oceania includes the aforenamed islands, adding AUSTRALIA; NEW ZEALAND; and the Malay Archipelago (INDONESIA). (Webster's New Geographical Dictionary, 1988, p910, 880)Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Oocysts: Zygote-containing cysts of sporozoan protozoa. Further development in an oocyst produces small individual infective organisms called SPOROZOITES. Then, depending on the genus, the entire oocyst is called a sporocyst or the oocyst contains multiple sporocysts encapsulating the sporozoites.Germine Acetates: Germine derivatives acetylated on any one or more of the hydroxy groups. These compounds are present in many polyester alkaloids which occur in Veratrum and Zygadenus species. They are used as antihypertensive agents, and in some cases, exhibit curare-like activity.AIDS-Related Opportunistic Infections: Opportunistic infections found in patients who test positive for human immunodeficiency virus (HIV). The most common include PNEUMOCYSTIS PNEUMONIA, Kaposi's sarcoma, cryptosporidiosis, herpes simplex, toxoplasmosis, cryptococcosis, and infections with Mycobacterium avium complex, Microsporidium, and Cytomegalovirus.DNA, Protozoan: Deoxyribonucleic acid that makes up the genetic material of protozoa.Lung Diseases, Parasitic: Infections of the lungs with parasites, most commonly by parasitic worms (HELMINTHS).Amebicides: Agents which are destructive to amebae, especially the parasitic species causing AMEBIASIS in man and animal.Recreation: Activity engaged in for pleasure.Coccidiostats: Agents useful in the treatment or prevention of COCCIDIOSIS in man or animals.Antiparasitic Agents: Drugs used to treat or prevent parasitic infections.Globosides: Glycosphingolipids containing N-acetylglucosamine (paragloboside) or N-acetylgalactosamine (globoside). Globoside is the P antigen on erythrocytes and paragloboside is an intermediate in the biosynthesis of erythrocyte blood group ABH and P 1 glycosphingolipid antigens. The accumulation of globoside in tissue, due to a defect in hexosaminidases A and B, is the cause of Sandhoff disease.Oxyfedrine: A drug used in the treatment of angina pectoris, heart failure, conduction defects, and myocardial infarction. It is a partial agonist at beta adrenergic receptors and acts as a coronary vasodilator and cardiotonic agent.Water Pollution: Contamination of bodies of water (such as LAKES; RIVERS; SEAS; and GROUNDWATER.)Vipoma: A tumor that secretes VASOACTIVE INTESTINAL PEPTIDE, a neuropeptide that causes VASODILATION; relaxation of smooth muscles; watery DIARRHEA; HYPOKALEMIA; and HYPOCHLORHYDRIA. Vipomas, derived from the pancreatic ISLET CELLS, generally are malignant and can secrete other hormones. In most cases, Vipomas are located in the PANCREAS but can be found in extrapancreatic sites.Seasons: Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Zoonoses: Diseases of non-human animals that may be transmitted to HUMANS or may be transmitted from humans to non-human animals.Vestibular Nuclei: The four cellular masses in the floor of the fourth ventricle giving rise to a widely dispersed special sensory system. Included is the superior, medial, inferior, and LATERAL VESTIBULAR NUCLEUS. (From Dorland, 27th ed)Coccidiosis: Protozoan infection found in animals and man. It is caused by several different genera of COCCIDIA.Craterostigma: A plant genus of the order Lamiales, family Linderniaceae.Antibodies, Protozoan: Immunoglobulins produced in a response to PROTOZOAN ANTIGENS.Electrons: Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Infectious Disease Incubation Period: The amount time between exposure to an infectious agent and becoming symptomatic.Drinking Water: Water that is intended to be ingested.Health ResortsIsospora: A genus of protozoan parasites found in the intestines of birds, amphibians, reptiles, and mammals, including man. The oocysts produce two sporocysts, each with four sporozoites. Many species are parasitic in wild and domestic animals.Cyclosporiasis: Infection with parasitic protozoa of the genus CYCLOSPORA. It is distributed globally and causes a diarrheal illness. Transmission is waterborne.Antigens, Protozoan: Any part or derivative of any protozoan that elicits immunity; malaria (Plasmodium) and trypanosome antigens are presently the most frequently encountered.WisconsinImmunoproliferative Disorders: Disorders characterized by abnormal proliferation of primary cells of the immune system or by excessive production of immunoglobulins.Fenthion: Potent cholinesterase inhibitor used as an insecticide and acaricide.Infusions, Intra-Arterial: Regional infusion of drugs via an arterial catheter. Often a pump is used to impel the drug through the catheter. Used in therapy of cancer, upper gastrointestinal hemorrhage, infection, and peripheral vascular disease.Fresh Water: Water containing no significant amounts of salts, such as water from RIVERS and LAKES.Schools, Veterinary: Educational institutions for individuals specializing in the field of veterinary medicine.Haiti: A republic in the Greater Antilles in the West Indies. Its capital is Port-au-Prince. With the Dominican Republic it forms the island of Hispaniola - Haiti occupying the western third and the Dominican Republic, the eastern two thirds. Haiti belonged to France from 1697 until its rule was challenged by slave insurrections from 1791. It became a republic in 1820. It was virtually an American protectorate from 1915 to 1934. It adopted its present constitution in 1964 and amended it in 1971. The name may represent either of two Caribbean words, haiti, mountain land, or jhaiti, nest. (From Webster's New Geographical Dictionary, 1988, p481 & Room, Brewer's Dictionary of Names, 1992, p225)Population Surveillance: Ongoing scrutiny of a population (general population, study population, target population, etc.), generally using methods distinguished by their practicability, uniformity, and frequently their rapidity, rather than by complete accuracy.Acquired Immunodeficiency Syndrome: An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993.Cattle Diseases: Diseases of domestic cattle of the genus Bos. It includes diseases of cows, yaks, and zebus.Water Wells: Constructions built to access underground water.Rain: Water particles that fall from the ATMOSPHERE.