The word parasite conjures up disgusting visions of enormous tapeworms or some tropical fly larvae emerging from a boil. The stuff of horror movies, parasites are actually common pests that can produce either serious disease or cause minor annoyance. Animals that live within, upon, and at the expense of are not so easy to get rid of, as these vermin continually seek a home and their next meal in an unsuspecting host.
Intestinal Infections
Fecal contamination of food or water is the most common mode of transmission for two types of parasites that inhabit human intestines: protozoa and helminths, according to the University of Maryland Medical Center. Abdominal pain, diarrhea that may contain blood or mucus, nausea, vomiting, gas, bloating, rectal itch, fatigue, and weight loss are common symptoms of intestinal parasites. Helminths are worms that are visible to the naked eye, such as tapeworms, pinworms or roundworms. They might be seen in the stool or, in the case of pinworms, captured using scotch tape near the rectum at night. The most common protozoal infections in the United States are giardia and cryptosporidium. Infections may be more serious in pregnancy, children, the elderly or those with already compromised immune systems.
Scabies
Caused by microscopic mites that are usually transmitted by direct, prolonged, skin-to-skin contact, scabies produces an intensely itchy, pimply skin rash. The mites burrow into the upper layer of skin, where they lay eggs. Scabies is a common problem where humans live in crowded conditions, such as in nursing homes and prisons. Application of a prescription lotion from head to toe is the recommended treatment. Scabies mites can survive up to 72 hours away from human skin; bedding, towels, and clothing should be laundered at high temperatures or sealed in plastic bags for at least 72 hours to prevent reinfestation.
Malaria
Malaria is a disease caused by a mosquito-borne parasite. According to the Centers for Disease Control and Prevention (CDC), asymptomatic infestation begins as the organisms grow and multiply in the human liver. When parasites make their way into the red blood cells, fever, chills, nausea, sweating, weakness and other flulike symptoms are the result. Microscopic analysis of blood is diagnostic. Most cases are uncomplicated and respond to treatment with drugs derived from medicinal plants. However, severe malaria can be life-threatening. Young children and pregnant women in endemic areas are most at risk. The CDC warns that even though malaria was considered eradicated in the United States in the 1950s, an average of 1500 cases are reported each year among travelers and immigrants. Three species of mosquitoes in the U.S. could potentially reintroduce the disease.
