Tapeworm!

A fellow walks into his doctor's office, complaining that he thinks he might have a tapeworm. The doctor makes a physical examination and listens to the symptoms, and concurs with the self-diagnosis.

"I want you to come back tomorrow, to start treatment. Bring a banana and a cookie with you," said the doctor.

Despite the seemingly odd request, our hero complies, and returns the next day with a banana and a cookie. The doctor says, "Okay, now drop your pants and bend over. This is going to hurt a bit."

Although leery about the turn of events, the patient drops his pants and bends over. The doctor peels the banana and with one deft motion rams it up the guy's butt. While the doctor consults his watch, our hero dances around the room shouting at the doctor.

"Okay, one minute is up, and we have to complete the second part of the treatment if your truly want to get rid of this tapeworm," advises the doc.

Despite the pain, the patient does want to be cured, so complies with the order to bend over again. Again, the doctor takes the cookie and rams it up the patients butt.

"Okay, tomorrow I want to see you here at the same time, and bring another banana and a cookie," says the doctor.

The now humbled patient, with tears of pain in his eyes, nods his head.

Next day, the same routine ensues. First the doctor rams up a banana, waits exactly one minute, then rams up a cookie. And the next day, and the next day and the next!! Every day UP goes a banana, wait one minute, then UP goes a cookie.

After one full week of treatments, the doctor finally says, "Well, tomorrow is the LAST day of treatments. I want you to bring in a banana and a hammer."

"Not a cookie?" asks the very frightened patient, trying to imagine what a hammer was going to feel like.

"Nope, a hammer," confirmed the doctor.

The last day the doctor says, "Okay, you know the routine".

So the man drops his pants and bends over. Up goes the banana, and the doctor looks at his watch and picks up the hammer. One minute passes. Then two minutes. Three. Four minutes pass.

Then a little head pokes out of the patients butt yelling, "WHERE'S MY COOKIE!?!"

Tapeworms

In biology, Cestoda is the class of parasitic flatworms, called cestodes or tapeworms, that live in the digestive tract of vertebrates as adults and often in the bodies of various animals as juveniles.

Tapeworm Overview

In a tapeworm infection, adult worms absorb food predigested by the host, so the worms have no need for a digestive tract or a mouth. Large tapeworms are made almost entirely of reproductive structures with a small "head" for attachment. Symptoms vary widely, depending on the species causing the infection.

Symptoms may include upper abdominal discomfort, diarrhea, and loss of appetite. However, infestations are usually asymptomatic. Worm segments or eggs may be found in the stool of an infected person. Tapeworms can grow 15 to 30 feet (10 metres) in length. The largest tapeworms grow up to 59 feet (18 metres). Most tapeworms enter humans through infected food, the same way they enter pets. Tapeworms harm their host by stealing vital nutrients, causing malnutrition and, if left untreated, can cause intestinal blockages.

There are two subclasses in class Cestoda, the Cestodaria and the Eucestoda. By far the most common and widespread are the Eucestoda, with only a few species of unusual worms in subclass Cestodaria. The cyclophyllideans are the most important to humans because they infect people and livestock. Two important tapeworms are the pork tapeworm, Taenia solium, and the beef tapeworms, T. saginata. Different types of tapeworms have radically different larval stages (see their specific articles).

Taenia solium and T. saginata are the most common tapeworms. A person can become infected by these parasites by eating raw or undercooked meat that has been infected. Symptoms generally include abdominal pain, diarrhea, nausea, and other gastrointestinal symptoms. Sometimes, the parasite may migrate to the appendix, pancreas, or bile duct causing severe abdominal pain.

Cysticercosis, a dangerous complication of the parasite Taenia solium, may occur when the larvae develop outside the intestinal tract. This parasite can move from the intestines to muscle tissue, bone marrow, fingers, and in some cases the central nervous system (neurocysticercosis). The latter infection can lead to seizures and other neurological problems.

A third type of tapeworm, Diphyllobothrium latum, is contracted by eating raw, infected fish. The fish become infected by eating infected crustaceans, which became infected by consuming untreated sewage. This tapeworm results in symptoms similar to those of T. saginata and Taenia solium, but can also include weakness and fatigue.

Tapeworm Adult morphology

Adult tapeworms share a basic body structure. All have a scolex, sometimes colloquially referred to as the "head," a "neck," and one or more proglottids, which are sometimes called "segments." These are the source of the name "tapeworm," because they look like a strip of tape. All cestodes have a nerve ring in the scolex with lateral trunks passing through the rest of the body.

Tapeworm Scolex

The Scolex or "head" of the worm attaches to the intestine of the definitive host. In some groups, the scolex is dominated by bothria, which are sometimes called "sucking grooves," and function like suction cups. Other groups have hooks and suckers that aid in attachment. Cyclophyllid cestodes can be identified by the presence of four suckers on their scolex, though they may have other structures.

While the scolex is often the most distinctive part of an adult tapeworm, it is often unnoticed in a clinical setting as it is inside the patient. Thus, identifying eggs and proglottids in feces is important.

Tapeworm Neck

The Neck of a tapeworm is a relatively undifferentiated mass of cells that divide to form new proglottid "segments." This is where all growth in an adult tapeworm occurs.

Tapeworm Proglottids

The body is composed of successive units posterior to the scolex, the proglottids. The sum of the proglottids is called a strobila, which is thin, resembling a strip of tape, and is the source of the common name tapeworm. Like some other flatworms, cestodes use flame cells (protonephridia) for excretion, which are located in proglottids.

Mature or gravid proglottids are released from the mature tapeworm and leave the host in its feces.

Because each proglottid contains the male and female reproductive structures, they can reproduce independently. It has been suggested by some biologists that each should be considered a single organism, and that the tapeworm is actually a colony of proglottids.

Tapeworm Treatment

CDC guidelines for treatment is a prescription drug called praziquantel (Biltricide). Praziquantel is generally well tolerated. Sometimes more than one treatment is necessary.

Tapeworms In popular culture

An episode of House M.D. (a primetime television drama) features a woman who has been infected with the pork tapeworm, Taenia solium. In this case the tapeworm has lodged one of its spawn into the woman's brain. To prove that there is a tapeworm infection, one of House's junior colleagues points out that an x-ray of the thigh muscles should be taken, as this is a "popular" spot for worm larvae to be found.