SOME TYPES OF PARASITES AND WHAT THEY DO:

What are parasites?
Parasites are organisms that derive nourishment and protection from other living organisms known as hosts. They may be transmitted from animals to humans, from humans to humans, or from humans to animals. Several parasites have emerged as significant causes of foodborne and waterborne illness. These organisms live and reproduce within the tissues and organs of infected human and animal hosts, and are often excreted in feces.

How are they transmitted?
They may be transmitted from host to host through consumption of contaminated food and water, or by putting anything into your mouth that has touched the stool (feces) of an infected person or animal.

How do they vary?
Parasites are of different types and range in size from tiny, single-celled, microscopic organisms (protozoa) to larger, multi-cellular worms (helminths) that may be seen without a microscope. The size ranges from 1 to 2 µm (micrometers) to 2 meters long.

What are some common parasites?
Some common parasites are Giardia duodenalis, Cryptosporidium parvum, Cyclospora cayetanensis, Toxoplasma gondii, Trichinella spiralis, Taenia saginata (beef tapeworm), and Taenia solium (pork tapeworm).


Roundworms can lay 200,000 eggs a day ! Over a million people are infected. Symptoms are upper abdominal discomfort. asthma, insomnia, appendicitis, peritonitis, and rashes due to the secretions or waste products from the worms. Large numbers can cause blockages in the intestinal tract, hemorrhage (bleeding) when penetrating the intestinal wall, abscesses in the liver, hemorrhagic pancreatitis, loss of appetite, and insufficient absorption of digested foods. Adults grow to 15 inches long.

Hookworm larvae penetrate the skin. When hookworms reach adulthood, they can sap the victim's strength, vitality and overall well-being. Young worms use their teeth to burrow through the intestinal wall and feed on your blood. Symptoms from hookworm are iron deficiency, abdominal pain, loss of appetite, protein deficiency, dry skin and hair, skin irritations, edema, distended abdomen, mental dullness, and eventually cardiac failure (yes you can die from this!)

Pinworms infects one in five children. Symptoms are itching and irritation of the anus or vagina, digestive disorders, insomnia, irritability or nervousness. Female worms crawl out of the anus and lay about 15,000 eggs per day. Once airborne, the eggs can survive about two days anywhere in your living environment.Worldwide, about 500 million are infected with pinworms. The worm is white and can grow to about half inch in length.

Whipworm infections are estimated at several hundred million worldwide. Symptoms of whipworms are bloody stools, pain in the lower abdomen, weight loss, rectal prolapse, nausea and anemia. Hemorrhage can occur when worms penetrate the intestinal wall and bacterial infections usually follow. 1 to 2 inches length.

Amoebae are microorganisms that infect the end of the smaller intestine and colon. They release an enzyme that causes ulcers or abscesses where they can enter the bloodstream. They can eventually reach other organs like the brain or liver.

Trichomonas vaginalis are pathogens that resides in the vagina in females and the urethra, epididymis, and swelling in the prostate gland in males. In women there is some yellowish discharge accompanied by itching and burning.

Tapeworms may grow to 35 feet long and live ten years inside the persons intestines. Some tapeworms can lay as many as one million eggs per day. Their bodies are in separate segments with hooks and suction cups on their skull.

Flukes; Flatworms- found in bladder, blood, liver, lung, kidney and intestines. Human infections of flukes are in excess of 250 million worldwide. They can cause severe disease of the gastrointestinal tract, bladder, liver and destroy blood cells. Size varies from 1 to 2.5 centimeters in length (1/2 to 3 inches long).

Spirochetes are very tiny organisms that are spiral-shaped, and multiply in the blood and lymphatic system. Spirochetes (largest), Saprospira, Cristispira, Treponema (smallest), and many more. The host or carrier is usually lice, ticks, fleas, mites, and flying insects, which is then transmitted to humans. Spirochetes are responsible for relapsing fever, infectious jaundice, Lymes disease, sores, ulcers, Vincent angina and Wyles disease.

Blastocystis hominis is a microscopic parasite in the world with the feces of humans, abdominal pain, diarrhea and other gastrointestinal symptoms were found. The infection is called Blastocystosis.

 

Giardia duodenalis or intestinalis (formerly called G. lamblia)

Giardia duodenalis, cause of giardiasis (GEE-are-DYE-uh-sis), is a one-celled, microscopic parasite that can live in the intestines of animals and people. It is found in every region throughout the world and has become recognized as one of the most common causes of waterborne (and occasionally foodborne) illness in the United States.

How do people get giardiasis?
People get giardiasis the following ways:
Giardiasis is frequently associated with drinking contaminated water, but some people might get infected by consuming uncooked meat also contaminated with G. duodenalis cysts (the infective stage of the organism).
By putting anything into your mouth that has touched contaminated surfaces or the stool of a person or animal with giardiasis.

Symptoms of giardiasis
Diarrhea, abdominal cramps, gas, and nausea are the most common symptoms. Chronic infection might lead to dehydration and severe weight loss. Some cases may be without symptoms.

When will symptoms appear? What is the duration?
Symptoms will usually appear 1 to 2 weeks after ingestion of a G. duodenalis cyst. They may last 2 to 6 weeks in otherwise healthy persons, but there are cases of chronic illnesses lasting months or even years.

Who is at risk for contracting giardiasis?
Those at risk include:
Day care providers and children attending daycare centers;
International travelers (traveler's diarrhea);
Hikers, campers, or any other persons who may drink from untreated or contaminated water supplies, including while swimming in lakes or rivers; and
Young children, pregnant women, older adults, and persons with weakened immune systems, including those with HIV/AIDS infection, cancer, diabetes, kidney disease, and transplant patients, or those individuals undergoing chemotherapy.

How to prevent giardiasis

Wash hands with warm water and soap before handling foods and eating, and after going to the bathroom, changing diapers, and handling animals.
Make sure infected individuals wash their hands frequently to reduce the spread of infection.
Drink water only from treated municipal water supplies.
When hiking, camping, or traveling to countries where the water supply may be unsafe to drink, either avoid drinking the water or boil it for 1 minute to kill the parasite. Drinking bottled beverages can be a safe alternative.
Do not swallow water while swimming.
Do not swim in community pools if you or your child has giardiasis.
Always cook your food to a safe internal temperature. Safe temperatures can be found at: www.fsis.usda.gov/Fact_Sheets/index.asp
Drink only pasteurized milk, juices, or cider.
Wash, peel, or cook raw fruits and vegetables before eating.
Do not use untreated manure to fertilize fruits and vegetables. Watering untreated manure can spread the organism.

Cryptosporidium parvum

Cryptosporidium parvum, cause of the disease cryptosporidiosis (KRIP-toe-spo-RID-e-O-sis) also called "Crypto", is a one-celled, microscopic shelled parasite and a significant cause of waterborne and foodborne illness worldwide. It is found in the intestines of many herd animals including cows, sheep, goats, deer, and elk. The illness could be intestinal, tracheal, or pulmonary.

How do people get cryptosporidiosis?
This parasite can be found in soil, food, water or surfaces that have been contaminated with feces from infected humans or animals.

People get cryptosporidiosis the following ways:
By consuming food or water contaminated with C. parvum oocysts (infective stage of the parasite). The oocysts are the environmentally resistant stage of the organism and are shed in the feces of a host (human or animal).
By putting anything into your mouth that has touched the stool of a person or animal with cryptosporidiosis.

Symptoms of intestinal cryptosporidiosis
Symptoms include watery diarrhea, stomach cramps, upset stomach, and slight fever. Some cases may be without symptoms.

When will symptoms appear? What is the duration?
Symptoms appear 2 to 10 days after ingestion of C. parvum oocysts. The illness usually goes away without medical intervention in 3 to 4 days. For healthy people, symptoms may last up to 2 weeks. For individuals with weakened immune systems, cryptosporidiosis can be serious, long-lasting, and sometimes fatal.

Who is at risk for contracting cryptosporidiosis?
Those at risk include:
Day care providers and children attending daycare centers;
Young children, pregnant women, older adults, and persons with weakened immune systems, including those with HIV/AIDS infection, cancer, diabetes, kidney disease, and transplant patients, or those individuals undergoing chemotherapy.
International travelers (traveler's diarrhea); and
Hikers, campers, or any other persons who may drink from untreated water supplies.

How to prevent cryptosporidiosis

Wash hands with warm water and soap before handling foods and eating, and after going to the bathroom, changing diapers, and handling animals.
Drink water only from treated municipal water supplies.
When hiking, camping, or traveling to countries where the water supply may be unsafe to drink, either avoid drinking the water or boil it for 1 minute to kill the parasite. Drinking bottled beverages can be a safe alternative.
Do not swallow water while swimming.
Do not swim in community swimming pools if you or your child has cryptosporidiosis.
Drink only pasteurized milk, juices, or cider.
Wash, peel, or cook raw fruits and vegetables before eating.
Do not use untreated manure to fertilize fruits and vegetables. Watering untreated manure can spread the organism.

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Cyclospora cayetanensis

Cyclospora cayetanensis (SIGH-clo-SPOR-uh KYE-uh-tuh-NEN-sis), cause of cyclosporiasis, is a one-celled, microscopic parasite. Currently little is known about this organism, although cases of cyclosporiasis are being reported from various countries with increasing frequency.

How do people get cyclosporiasis?
People get cyclosporiasis the following ways:
By consuming food or water contaminated with C. cayetanensis oocysts (the infective stage of the organism).
By putting anything into your mouth that has touched the stool of a person or animal with cyclosporiasis.

Toxoplasma gondii

Toxoplasma gondii, cause of the disease toxoplasmosis (TOX-o-plaz-MO-sis), is a single-celled, microscopic parasite found throughout the world. It is the third leading cause of death from foodborne disease. It is interesting to note that these organisms can only carry out their reproductive cycle within members of the cat family. In this parasite-host relationship, the cat is the definitive host. The infective stage (oocyst) develops in the gut of the cat. The oocysts are then shed into the environment with cat feces.

How do people get toxoplasmosis?
People get toxoplasmosis the following ways:
By consuming foods (such as raw or undercooked meats, especially pork, lamb, or wild game) or drinking untreated water (from rivers or ponds) that may contain the parasite.
Fecal-oral: Touching your hands to your mouth after gardening, handling cats, cleaning a cat's litter box, or anything that has come into contact with cat feces.
Mother-to-fetus (if mother is pregnant when first infected with T. gondii).
Through organ transplants or blood transfusions, although these modes are rare.

Trichinella spiralis

Trichinella spiralis, cause of trichinellosis (also known as trichinosis) (TRICK-a-NO-sis) is an intestinal roundworm whose larvae may migrate from the digestive tract and form cysts in various muscles of the body. Infections occur worldwide, but are most prevalent in regions where pork or wild game is consumed raw or undercooked. The incidence of trichinosis has declined in the United States due to changes in hog feeding practices. Presently, most cases in this country are caused by consumption of raw or undercooked wild game.

How do people get trichinellosis?
People get trichinellosis (trichinosis) by consuming raw or undercooked meats such as pork, wild boar, bear, bobcat, cougar, fox, wolf, dog, horse, seal, or walrus infected with Trichinella larvae.

Taenia saginata/Taenia solium (Tapeworms)

Taenia saginata (beef tapeworm) and Taenia solium (pork tapeworm) are parasitic worms (helminths). Taeniasis is the name of the intestinal infection caused by adult-stage tapeworms (beef or pork tapeworms). Cysticercosis is the name of the tissue (other than intestinal) infection caused by the larval-stage of the pork tapeworm only.

It is interesting to note that humans are the definitive hosts of both organisms. This means that the reproductive cycle, and thus egg production by the organisms, occurs only within humans. Eggs are passed in human feces and they may be shed into the environment for as long as the worms remain in the intestines (for as long as 30 years). In addition, the eggs may remain viable in the environment for many months.

These diseases are more prevalent in underdeveloped countries where sanitation practices may be substandard and in areas where pork and beef are consumed raw or undercooked. They are relatively uncommon in the U.S., although travelers and immigrants are occasionally infected.

How do people get Taeniasis?
People get Taeniasis by consuming raw or undercooked infected beef or pork.