Worms are parasites that infect humans through food, water and environmental pollution. The name is derived from the Greek word “para” and “sitos”. Para means resides while sitos means food. There are over 100 different type of parasitic worms that cam inhabit the human body. Some have more harmful effect on the human system than others. Some are too small to be detected by human eyes and thus called microscopic in size while others are large enough to be seen with the eyes. Their size ranges from a part of a thousandth micron to whale like worms which can measure about 100 feet. Worms inhabit and inflict the small and large human intestines.

Since worms are parasitic they normally require a host to live in and feed on. They thus draw their nutrients from the host and thus become harmful to the human host. Their activities also cause a number of diseases. Some worms can live in both human and animal host and thus can be transmitted from one to the other, thus pets and animals are a popular source of worms in humans. Some parasitic worms require a human host to complete their life cycle so they could begin from animals and then look for a human host to spread in.

Common symptoms of worm infection in humans include constipation, bloated stomach, anemia, diarrhea, asthma, digestive track infection, digestive disorders, nervousness, low immune resistance, skin rash, health problems and other diseases. Worms are considered as common parasites and many might not consider an infection as serious but worm in humans could lead to serious intestinal infection and health problems.

Some examples of common parasites or worms in humans include Nematodes, hookworms, roundworms, whipworms, heartworms and pinworms.
Roundworms are quite popular and resemble the common earth worm. They could produce about 200,000 eggs on a daily basis and are believed to be affecting about 1,008 million people. They are the most common worm infliction worldwide. Usual systems include asthma, eye pain, rashes, insomnia and discomfort in upper abdomen (most common). Large numbers affecting a person could block the intestinal tract and lead to hemorrhage, appendicitis, peritonitis, liver abscess, appetite loss and low food absorption. Adult size could be as long as 15 inches.
Hookworm infests a person when the larva penetrates the skin. At adult stage they begin to draw enough nutrients to sap the host’s strength and vitality. The younger worms bore the intestine wall and suck on the blood of host. The symptoms of hookworms include abdominal pain, lack of iron, appetite loss, and desire to eat soil, lack of protein dry hair and skin, edema, irritation of skin, stunt growth, metal dullness, and delay of puberty, distended abdomen, cardiac problems and even death. They measure about half an inch.
Pinworms are more common in children with an estimated 1 in 5 children affected worldwide. The symptoms include digestive disorders, irritation of the anus, insomnia, nervousness and irritability. The female pinworm crawls out of the anus to lay eggs and could lay as much as 15,000 eggs a day. The eggs get airborne and can survive for about 2 days searching for a host. An estimated 500 million people are affected with pinworms. They grow up to half an inch and are white in color.

Whipworms affect millions of people worldwide. Its symptoms include pain in the lower abdomen, loss of weight, anemia, nausea, rectal prolapse and hemorrhage. Hemorrhage occurs when the worms that could get up to 2 inches long penetrate the intestine wall and cause bacterial infection.

Worms in humans are harmful. It could lead to serious diseases when left untreated. A clean environment reduces the risk of an infection as well as clean cooking and food storage methods. Foods should be properly cooked and washed before eaten. It is advised that humans take medications to de-worm themselves every 3 months.