ARE THERE DIFFERENT TYPES OF TAPEWORMS?

Yes. There are many different types of tapeworms. There are some tapeworms that are specifically found in beef, some that are found in pork, and some that are found in fish. In the United States, beef and fish tapeworms are uncommon and the pork tapeworm is extremely rare. Another type of tapeworm is called the dwarf tapeworm, so named because it is only one inch long. The dwarf tapeworm is present all over the world, but is especially found in tropical areas. The dwarf tapeworm mostly affects children.

As will be discussed below, some forms of tapeworms can cause a condition known as hydatid disease. One such tapeworm is called the hydatid tapeworm. There is also a tapeworm found in sheep that is referred to as the fringed tapeworm of sheep. Its scientific name is Thysanosoma actinoides. The scientific name for the pork tapeworm is Taenia solium. The scientific name for the beef tapeworm is Taenia saginata. The scientific name for the broad fish tapeworm is Diphyllobothrium latum. The scientific name for the dwarf tapeworm is Hymenolepsis nana. The scientific name for the hydatid tapeworm is Echinococcus granulosis.

WHAT LEADS PEOPLE AND OTHER ANIMALS TO GET TAPEWORMS?

Early, immature forms of tapeworms can be present in some types of infected beef, pork, and fish. Cooking the fish and meat long enough will kill the tapeworms. Tapeworms are usually acquired when people eat meat or fish that has not been cooked enough. The tapeworms produce eggs in the intestines which then get passed out of the body in the feces (poop). If human feces wind up in the environment (due to poor sewage, for example) the tapeworm eggs may wind up in soil, grass, and water. When this happens, other animals, such as cows, dogs, pigs, and fish may consume the tapeworm eggs.

The tapeworms can then break out of the eggs when they are inside the animal's intestines. The first form of the tapeworm (known as a hexacanth) attaches itself to the wall of the intestine and continues to grow and develop. The tapeworm will develop into an adult when it is passed on to live in another organism. For example, the tapeworm can be in preadult form when it lives in a human and can develop into an adult form when it is passed on to a dog. From the above information, you can see that tapeworms can live in more than one animal at different points in their lives.

Another way that people acquire tapeworms is by touching feces that have tapeworm eggs in them and later putting their fingers in their mouths. Although it may seem like common sense not to do this, it can happen by accident.

WHAT ARE SIGNS AND SYMPTOMS OF HAVING TAPEWORMS?

Although beef, pork, and fish tapeworms can be very large, they rarely cause symptoms except for diarrhea and an upset stomach. Dwarf tapeworms also cause these symptoms. One sign of having tapeworms can be if pieces of the tapeworm break apart and come out through the anus (the area of the body that poop comes out of) or appear in the feces (poop).

Tapeworms can lead to cysts in an animal's muscles and other organs. A cyst is an abnormal lump, swelling, or sac that contains fluid, a part solid material, or a gas, and is covered with a membrane. A membrane is a thin layer of flexible tissue that covers something. The cysts can develop in organs such as the liver and lungs, a condition known as hydatid disease. The liver is the largest organ in the body and is responsible for filtering (removing) harmful chemical substances, producing important chemicals for the body, and other important functions. The lungs are two organs in the body that help people breathe.

HOW ARE TAPEWORMS DIAGNOSED?

Tapeworms are diagnosed when a doctor finds segments of the worms and/or eggs present in the poop.

HOW ARE TAPEWORMS TREATED?

Tapeworms are treated by giving the person or animal medications that kill the worms. Treating pork tapeworms can be difficult because the eggs may get pushed back into the stomach. If this happens, the tapeworms can get deep into the tissues and form cysts. This can lead to a condition known as cysticercosis, in which muscle pains and convulsions occur. Convulsions are abnormal, severe, involuntary muscle movements. See the signs and symnptoms section for a description of cysts.

CAN TAPEWORMS BE PREVENTED?

Despite the fact that tapeworms occur all over the world, acquiring tapeworms can be prevented. To begin with, meat and fish need to be properly inspected so that infected pieces are not sold to the public. Since some bad meat and fish is bound to get by inspectors, it is suggested that people cook meat and fish thoroughly so that they do not risk acquiring tapeworms. Disposing of garbage and waste properly are also good ways to prevent the spread of tapeworm eggs, which can lead to people and animals acquiring tapeworms.

WHAT ELSE ARE TAPEWORMS CALLED?

Tapeworms are also known as cestodes.

WHAT IS THE ORIGIN OF THE WORD, TAPEWORM?

Tapeworm comes from the Old English word "taeppe" meaning "narrow strip of cloth used for tying" and the Old English word "wyrm" meaning "serpent." The tapeworm was given its name because it resembles a narrow strip of cloth used for tying.