ROUNDWORM (NEMATODA) Roundworm, also called nematode or eelworm, more than 12,000 species . Most kinds of roundworms live freely in soil, water, dead plants, or dead animals. Other roundworms are parasites. on living plants and animals, which serve as hosts. Some parasitic species cause serious diseases in people, livestock, and crop plants. One species of roundworm, Caenorhabditiselegans, has proven especially valuable in biological research.
14 species of roundworms • cause infection in human beings. • Trichuristrichiura • filariae, • hookworms, • pinworms, • trichinae. • lumbricoides,. • The vinegar eel
Trichuristrichiurainfects the large intestine and occurs in millions more people worldwide. It causes trichuriasis, a disease characterized by diarrhea. Other common roundworms that cause disease in human beings include lumbricoides, which inhabits the small intestine, infects millions of people around the world. It causes a disease called ascariasis. Symptoms of this disease include pneumonia and intestinal pain. The vinegar eel is a tiny roundworm that lives in vinegar. They feed on fruit pulp and the bacteria that produce the vinegar from the cider. Vinegar eels are harmless when swallowed. The vinegar eel is slender and threadlike and about 1/16 inch (1.6 millimeters) long. There are separate males and females. Most female vinegar eels live about 10 months and produce as many as 45 tiny larvae, which are about 1/100 inch (0.25 millimeter) long.
Nearly all species of roundworms reproduce by laying eggs. Ascarislumbricoides each lay about 200,000 eggs per day for at least 10 months. In many roundworms, the eggs hatch into tiny young that look like adults. Eggs of other species hatch into young called larvae, which gradually transform into adults. Roundworms that do not lay eggs give birth to larvae. Parasitic roundworms may infect a host in a number of ways. Some species enter the host when the host swallows food that contains the roundworm, its eggs, or its larvae. Among other species, the larva burrows into the skin of the host. In still other species of roundworms, the larva is taken up by an insect, such as a fly or a mosquito, and transmitted through the bite of that insect to the host.
PINWORM (Enterobiusvermicularis) Enterobiusvermicularis, commonly infects humansPinworm, also called threadworm, is a small roundworm. Pinworms are parasites, they live in the body of other animals. They are about 3/8 inch (9 millimeters) long and have white bodies and pointed tails. Some pinworms infect horses and rabbits.
Pinworms are not very harmful unless they are present in large numbers. But their eggs may infect other people or reinfect the original carrier. In some areas, 10 to 60 percent of the children may have pinworms at some time. Health care providers use drugs to treat infection caused by pinworms. Scientific classification. Pinworms belong to the family Oxyuridae and the phylum Nematoda.
The young worms live in the upper part of the large intestine. When the females are ready to lay eggs, they crawl down the rectum and out the intestinal (the anus), usually at night. They lay eggs on the surrounding skin. This movement causes skin swellings and severe itching. The eggs fall off onto the bedding or clothing, or may be picked up under fingernails in scratching. If the eggs are swallowed, they reach the intestine and become adult pinworms.
TRICHINA (TRICHINELA SPIRALIS) Trichina is a small roundworm that causes the disease trichinosis, also known as trichinellosis. The worm is a parasite. That is, it lives in and feeds on other animals. Trichina is of the genus Trichinella, which causes trichinosis in humans from eating undercooked pork. Modern farming practices and meat inspections have made this disease rare in the United States.
The trichina infects human beings and other animals, especially rats, hogs, and bears. Most infections of trichinosis result from eating infected pork that has not been cooked enough. Trichinosis in rats, hogs, and bears usually results from eating garbage that contains infected meat. The larvae (early form of the worms) live in microscopic cysts (sacs) in the muscles of the animals that they infect. They usually live in the animal's chest and neck muscles.
If an animal infected by the larvae is allowed to live, the cysts eventually harden, and the larvae die. In such cases, the larvae can be killed by cooking or freezing the meat. the larvae are not killed and the meat is eaten, the larvae are freed from the cysts during digestion. The larvae attach themselves to the intestine of the individual who eats the meat. They become adult worms in about 3 or 4 days. The largest are only about 1/4 inch (6 millimeters) long.
the adult females burrow into the wall of the intestine, where they produce large numbers of larvae. The larvae enter the blood and are carried to many parts of the body. They eventually leave the blood and form new cysts in the muscles.
SYMPTOMS Some people never have severe symptoms. The worms irritate the intestine and cause diarrhea, nausea, and vomiting. When pass the blood, fever, headache, and muscular pain occur. In the muscles, cause swelling of the face and other parts and bleeding under the skin. Form cysts in the diaphragm and make breathing painful occasionally is fatal. Trichinosis is a disease by eating undercooked meat, contains cysts in pork, bear, fox, rat, horse, and lion meat.
The prevention of trichinosis involves several steps. Garbage may carry trichina worms, be cooked before it is fed to hogs. Meat packers should freeze pork to kill any worms. Finally, cooks should be sure the central section of pork is held at a temperature of at least 137°F (58°C) for 5 minutes or more. Scientific classification. The trichina is in the trichina family, Trichinellidae. Its scientific name is Trichinellaspirallis
WHIPWORMThe human whipworm (Trichuris trichiura or Trichocephalus trichiuris), is a roundworm, which causes trichuriasis when it infects a human large intestine. The name whipworm refers to the shape of the worm; they look like whips with wider "handles" at the posterior end. WHIPWORMThe human whipworm (Trichuris trichiura or Trichocephalus trichiuris), is a roundworm, which causes trichuriasis when it infects a human large intestine. The name whipworm refers to the shape of the worm; they look like whips with wider "handles" at the posterior end. WHIPWORM The nematode Trichuristrichiura, also called the human whipworm. The adult female measures about 35-50 mm in length, and the male about 30-45 mm. The Trichuristrichiura or Trichocephalustrichiuris, is a roundworm, causes trichuriasis when it infects a human large intestine. The name whipworm refers to the shape of the worm; they look like whips with wider "handles" at the posterior end.
Life Cycle 1.The unembronated eggs are passed with the stool , 2.In the soil, the eggs develop into a 2-cell stage , 3.and advanced cleavage stage , 4.and then they embryonate, 5.eggs become infective in 15 to 30 days. After ingestion (soil-contaminated hands or food), the eggs hatch in the small intestine, 6.release larvae that mature as adults in the colon The adult worms (4 cm) in the cecum and ascending colon. The adult worms are fixed with the anterior portions threaded into the mucosa. The females begin to oviposit 60 to 70 days after infection. Female worms in the cecum shed between 3,000 and 20,000 eggs per day. The life span adults is about 1 year.
Geographic Distribution: The third most common roundworm of humans. Worldwide, with infections more frequent in areas with tropical weather and poor sanitation practices, and among young children. It is estimated that 800 million people are infected worldwide.
SYMPTOM & SIGN Symptoms Include: 1.Light infestations are frequently asymptomatic. 2.Heavy infestations may have bloody diarrhea. 3.Long-standing blood loss lead to iron-deficiency anemia. 4.Rectal prolapse is possible in severe cases. DIAGNOSTIC &TREATMENT Whipworm by stool examination, can detect eggs and charcot-leyden crystals. Mebendazoleis 90 percent effective in the first dose, and albendazole may also be offered as an anti-parasitic agent. Adding iron solve the iron deficiency and rectal prolapse.
SCHISTOMIASIS • Schistosomiasisis caused by five species : • Schistosomamansoni • Schistosomajaponicum • Schistosomahaematobium • Schistosomamekongi • Schistosomaintercalatum
Fresh water snails of the genus Biomphalaria, Bulinusand Oncomelania species specific intermediary host of the parasites. The infective larvae penetrate the skin of humans who enter snail infested water. Thus infection does not require physical contact between man and snail.
The onset of the disease may be characterized by itching and rash, shortness of breath and cough and rare a fatal immunological reaction known as Katayama syndrome. The disease has two forms; urinary schistosomiasis caused by S. haematobium and intestinal schistosomiasis caused by the other four species.
S. haematobium early symptom of blood in the urine, major pathologic lesions in the walls of the urinary bladder often extending to the ureter, kidney, urethra and genitalia. It is accompanied by incontinence, and constant and increasing pain upon urination. also lower abdominal pain, bladder colic and weakness Intestinal schistosomiasis major pathological lesions of the intestine, particularly the colon, cecum and rectum as a result of worm-eggs passing through or calcifying in the tissues. Dysentery, accompanied by abdominal pain, enlargement of spleen and liver as well as arterial obliteration in the lungs are symptoms of severe cases.
Schistosomiasis control strategies have shifted away from the elimination of infection or interruption of transmission toward control of the human disease with chemotherapy. Snail host control should be a supportive part of an integrated control activities. The best strategies must be community-based and should include primary health care, especially as relating to health education, food and nutrition, water supply and sanitation, maternal and child health and drug distribution.
ANISAKIS Anisakisis a genus of parasitic nematodes, which have a life cycle involving fish and marine mammals. They are infective to humans and cause Anisakiasis, fish which have been infected with Anisakis spp. can produce an anaphylactic reaction in people who have become sensitized to Immunoglobulin E (IgE).
Anisakids pose a risk to human health in two ways: 1. worms from the eating of under-processed fish, 2. allergic reactions to chemicals left by the worms in fish flesh. Anisakiasis is the disease caused by infection with Anisakis worms. the world where fish is consumed raw, lightly pickled or salted. Highest prevalence are a.Scandinavia(from cod livers), b.Japan(after eating sushi and sashimi), c.Netherlands(by eating infected fermented herrings [Maatjes]), d. the Pacific coast of South America (from eating ceviche). An effective method of killing Anisakis : Heating to 60°C, or freezing to below -20°C is
Life Cycle Complex life cycle of Anisakis worms. 1.Eggs hatch in sea water and larvae are eaten by crustaceans, usually Euphausids. 2.The infected crustacean is eaten by a fish or squid and into the wall of the gut and encysts in a protective coat, the outside of the visceral organs, in the muscle or beneath the skin. The life cycle is completed when 3.an infected fish is eaten by a marine mammal, (whale, seal, or dolphin). 4.The nematode excysts in the intestine, feeds, grows, mates and releases eggs into the sea water in the host's feces. Anisakisspp.infecthumans eat raw or undercooked fish.
symptoms Within hours after ingestion of infective larvae, 1.violent abdominal pain, nausea, and vomiting may occur. If the larvae pass into the bowel, 2.a severe eosinophilic granulomatous response may also occur 1 to 2 weeks following infection, causing symptoms mimicking Crohn's disease. Diagnosis : gastroscopicexamination during which the 2 cm larvae are visualized and removed, or by histopathologicexam.oftissue removed at biopsy or during surgery. Humans are thought to be more at risk of Anisakiasis from eating wild fish than farmed fish. Many countries require all types of fish with potential risk intended for raw consumption to be previously frozen to kill parasites.
Allergic Reactions Even when thoroughly cooked,Anisakis pose a health risk to humans. Anisakids (and related species such as the sealworm, Pseudoterranova spp., and the codwormHysterothylaciumaduncum) release a number of biochemicals into the surrounding tissues when they infect a fish. People who are sensitized to nematodes can have severe anaphylactic reactions after eating fish which have been infected with Anisakis spp. This is often confused with a fish or shellfish allergy, as the allergenic Anisakids are difficult to test for and often produce a reaction in tests for other allergens.
TREATMENT Humans are a dead-end host. Anisakisand Pseudoterranovalarvaecannot survive in humans and eventually die. Treatment of cases is symptomatic. The only indication for treatment is small bowel obstruction due to Anisakis larvae, emergency surgery, treatment with albendazole alone (avoiding surgery) being successful. Occurrence: Larval anisakis are common parasites of marine and anadromous fish, and can also be found in squid and cuttlefish. In contrast, they are absent from fish in waters of low salinity, due to the physiological requirements of Euphausids, which are needed to complete their life cycle. Anisakidsare also uncommon in areas where cetaceans are rare, such as the southern North Sea.
TAPEWORMThe cestodes (tapeworms), class Cestoda, are parasitic tapeworms. Two cestodes: 1. Taeniasaginata (beef tapeworm) and 2.Taenia solium (Pork tapeworm). T. saginata may measure 9 meters (27 feet), whereas T. solium may reach 6 meters (18 feet). (also cause cysticerosis).
Life Cycle Life Cycle of Taeniasaginata and TaeniasoliumHumans the only definitive hosts for T.saginataand Taeniasolium. 1.Eggs or gravid proglottids are passed with feces the eggs can survive for days to months in the environment. 2.Cattle (T. saginata) and pigs (T. solium) become infected by ingesting vegetation contaminated with eggs or gravid proglottids. 3.In the animal's intestine, the oncospheres hatch , invade the intestinal wall, and migrate to the striated muscles, where they develop into cysticerci. A cysticercus can survive for several years in the animal. 4.Humans become infected by ingesting raw or undercooked infected meat . In the human intestine, the cysticercus develops over 2 months into an adult tapeworm, which can survive for years. 5.The adult tapeworms attach to the small intestine by their scolex. 6. reside in the small intestine . .
Geographic Distribution: Both species are worldwide in distribution. Taeniasolium is more prevalent in poorer communities where humans live in close contact with pigs and eat undercooked pork, and is very rare in Muslim countries. All tapeworms are parasitic, without sense organs, mouths, or digestive tracts. Since they live in the intestine of their host, they can absorb nutrients directly through their body. The tapeworm consists of a scolex (head) and proglottids (body sections). The oldest proglottids are at the posterior end of the worm. Each proglottid contains reproductive organs. Tapeworm eggs can be fertilized by either cross-fertilization or self-fertilization.
GENERAL PREVENTION & TREATMENT • PARASITE CLEANSING • Medicine targets one or two types of parasites, • produce heavy side effects. 1.In order to rid the body of parasites it is best • to do parasite cleanse of the body. 2.In order to eradicate the infestation an eight week • parasite cleanse is recommended and for children two weeks. 3.It is best if children practice washing their hands • after playing outside and before they eat. 4.Pets that are infected should be treated immediately 5.The use of pills and liquid medicine are available • to start the process of treatment. • 6.Most times it helps to use two products • when cleansing since many times there are more • than on parasite infecting the person.