Lesson – some of the most common diseases among children and adults. In the human body can parasitize various species of worms. There is an opinion, far from medicine, in which helminths affect not only the digestive tract, in fact, worms can parasitize virtually all internal organs – liver, lungs, heart, brain, head, and muscle tissue, the subcutaneous tissue and in the eye. The article talks about how there are worms in humans.
Classification
There are a huge number of worms that can affect a person's, here are the most common ones. Most of the worms relates to any of the 3 groups, trematodes, cestodes or nematodes.
Flukes are a class of parasitic worms flat shapes, there are about 40 species of worms that affect man. The most common:
- cat or Siberian Fluke (causes opisthorchiasis);
- Schistosoma (causing schistosomiasis).
Cestodes – tape worms is flat. The representatives of cestodes is no digestive system. Most of the man are staggering:
- beef tapeworm (beef tapeworm infection causes);
- pork tapeworm (causing cysticercosis);
- Echinococcus (hydatid cyst causes).
The Nematoda is roundworms, which is primarily abdominal. Common worms that affect humans:
- pinworms;
- roundworm;
- the whipworm.
Worms in humans — signs in the photo (most of the worms affects the digestive tract, hence nausea and vomiting, diarrhea or constipation, intestinal obstruction, unexplained weight loss, lack of appetite or excessive hunger):
Cat or Siberian Fluke
Cat or Siberian Fluke – a small parasite lanceolate from the group of liver flukes. The causative agent of the disease opisthorchiasis. A length of cat Fluke reaches 8-18 mm in width and 1.2-2 mm. the Parasite develops in the body of the two hosts, both intermediate and final. Intermediate hosts – molluscs and fish carps, final – man.
Together with faeces of infected people and animals, the eggs get into freshwater reservoirs, where they ingest shellfish. In the body of a mollusk eggs reach the infective stage – cercaria, cercaria leave the mollusk and implanted in the body of cyprinid fish or get into their bodies by eating fish and shellfish. In the body of the fish the parasite develops to the meta-cercaria, which is in the cyst, its size reaches about 0.17-0.21 mm.
In the absorption detection of fish infected people, their body meta cercaria leave the cysts from the stomach and intestine they pass into the liver and bile ducts. In these organs they remain parasite, and 10-12 days to reach the Mature stage, they begin to lay eggs. In the human body cat Fluke can parasitize up to 10-20 years.
Shistosoma
Schistosoma – blood flukes. It is a flat dioecious helminths, has a length of 4-20 mm, width – 0.25 mm. Body shistosoma equipped with 2 suckers – oral and ventral, they are located close to each other. Females of Schistosoma longer and thinner than males. On the body of the male has a longitudinal groove, he keeps the female. Their eggs are 0.1 mm in diameter, oval in shape, on the surface of one of the poles is a large spike.
Human worms Schistosoma in the role of the definitive host choose the people in their organisms they parasitize in the small veins of the colon, abdominal cavity, uterus, bladder. Worms feed on blood, partly absorbed nutrients through the cuticle. Shistosoma eggs are transported to the intestine and bladder, where Mature and are excreted out with the feces or urine. In the fresh waters of the egg comes out the larva, its intermediate hosts – mollusks. In the body of the mollusk meta cercaria cercaria develop to 4-8 weeks.
Beef tapeworm
Beef tapeworm – band parasite that causes a disease beef tapeworm infection. This is a huge helminths, are able to grow to 3-12 meters long. On the body of the parasite is a small head with a diameter of 3 mm, the neck, and about 1000 segments. After entering the human body along with raw meat infected with tapeworm attaches to the intestinal wall with the help of 4 suction cups.
In hermaphroditic segments are deposited the eggs of the helminth, annually one individual lays up to 600 million eggs. Like worms in humans, parasitic in the intestine of 20 years or more, if there is no timely treatment.
Pork tapeworm
Pork tapeworm as bullish, the body has 4 suckers but in addition the body of the helminth has a dual rim hooks. Reaches two to three meters in length. Have a pork tapeworm before the ovary, with each side of the uterus has 7 to 12 branches. A characteristic feature of helminth – ability of the segments to crawl out of the anus. After the release of out their shell becomes dry and bursts, so the external environment are helminth eggs. Intermediate host tapeworm can be pigs and people.
The main host was a man. Intestinal parasites in humans include the pork tapeworm, is a helminth in the intestine of the patient, where it lays its eggs. The infection occurs in the use of invasive meat.
Echinococcus
The causative agent of echinococcosis in length reaches 3-5 mm. Consists of a head, which has four suckers and two rim hooks and three or four segments. The last of the segments has a developed reproductive system. Intermediate host – cattle or people, the final host – dog, wolf. Infection occurs by the oral route.
Echinococcus enters the intestine where eggs emerge the larvae. With the help of hinges larvae penetrate into the portal vein, where are carried with the blood to the liver, lungs, muscle tissue.
Pinworms
Pinworms – roundworms, enterobiasis pathogens, the so-called disease of dirty hands. To a greater extent of infection pinworm susceptible children. Infection occurs orally and by contact-household. To detect these worms in the stool.
Females helminths pinworms of the genus reach a length of 5-10 mm, males – 3 millimeters. The shape of the body in pinworms fusiform milky white. The end of the body females are slightly pointed. Adult worms are parasitic in the lower small intestine and colon of man, being attached to the wall using a head vesicles. In order to lay eggs, the female pinworms pass to the rectum, crawl out and lay eggs in the anal area, then die. Its eggs become infective after 4-6 hours. The life expectancy of pinworms is one to two months.
Roundworm
Roundworm – even some representatives of the class of roundworms parasites, the causative agents of ascariasis. This is the helminths yellowish – pink colour, have an elongated, spindle shaped, dioecious. Female ascarids grow up to 20-40 cm, males reach a length of 15-25 centimeters. Every day an adult female roundworm lays more than 200 thousand eggs, which, together with feces of a person stand out in the environment, where after 12-14 days become invasive.
In the human body parasites in the gastrointestinal tract, mainly localizes in the small intestine. Full cycle of development from the infective eggs to Mature stage takes about 3 months.
Whipworm
Whipworm – round worms that cause trihozefalez. Worms are a thin brown nematodes with thin, threadlike anterior portion and a rounded posterior end. Female whipworm grow to 3.5-5.5 inches, and males up to 3-4,5 cm. Larvae worms human are localized in the caecum, where and are parasitic to the stage of puberty, there lay their eggs. With a massive invasion of helminths can also take the colon, including the rectum.
Every day the female whipworm lays on 3,5 thousand eggs. Helminth eggs have a barrel shape, covered with a thick brown shell, the poles are located colorless "cap". The eggs get into the soil along with the faeces of the primary host, under favorable conditions they can retain invasive properties of up to two years. Duration of parasitism in the human intestine is 5-7 years.