Presentation on theme: "Parasite lab by l.wafa menawi. Hookworms The hookworms cause hookworm disease, which is one of the five major parasitic disease in China(malaria, shistosomiasis,"— Presentation transcript:
parasite lab by l.wafa menawi
Hookworms The hookworms cause hookworm disease, which is one of the five major parasitic disease in China(malaria, shistosomiasis, filariasis, kala- azar and hookworm disease). At least two species of hookworms infect man, Necator americanus and Ancylostoma duodenale. They live in small intestine.
parasite lab by l.wafa menawi Hookworms Ancylostoma is found in Europe around the Mediterranean, on the West coast of South America and in parts of China and India Necator is found over much of the western hemisphere, Africa and South East Asia More than a billion people infected
parasite lab by l.wafa menawi Hookworms Acylostoma was found coal and other mines throughout Europe At the turn of the last century, severe hookworm disease was an officially recognized occupational hazard in German coal mines and an eligible disease for workman’s compensation
parasite lab by l.wafa menawi Hookworms Hookworms were wide spread in the Southern USA. Hookworm control programs were a big part of the public health campaign in the South during and right after World War II % of school children from rural costal Georgia tested positive for hookworm infection
parasite lab by l.wafa menawi Morphology 1. Adults: They look like an odd piece thread and are about 1cm. They are white or light pinkish when living. ♀ is slightly larger than ♂.The male’s posterior end is expanded to form a copulatory bursa.
parasite lab by l.wafa menawi 2. Eggs: 60×40 µm in size, oval in shape, shell is thin and colorless. Content is 2-8cells.
parasite lab by l.wafa menawi Adults of A. duodenaleAdults of N. americanus Differences between two hookworms
parasite lab by l.wafa menawi Acylostoma duodenale & Necator americanus -- human hookworms Small nematodes (1-1.5 cm) Head is slightly bend (hook) and the ‘mouth’ carries characteristic teeth (Ancylostoma) or plates (Necator, note that these are not real teeth but cuticular formations of the ‘buccal capsule) The posterior end of the male worm is elaborated into a copulatory bursa
parasite lab by l.wafa menawi Scanning electron micrograph of the mouth capsule of Ancylostoma duodenale, note the presence of four "teeth," two on each side.
parasite lab by l.wafa menawi Scanning electron micrograph of the mouth capsule of Necator americanus, another species of human hookworm. Note the presence of two cutting "teeth“.
parasite lab by l.wafa menawi Ancylostoma duodenale - copulatory bursa and spines of male(a side view)
parasite lab by l.wafa menawi Copulatory bursa of N. americanus(a side view)
parasite lab by l.wafa menawi Left picture: Copulatory bursa and spines of N. americanus(a side view); Right picture: copulatory bursa of A. duodenale(a top view)
parasite lab by l.wafa menawi Morphologically it is not possible to differentiate between A. duodenale and N. americanus. Interference contrast. ×400. Enlarged by 5.4.
parasite lab by l.wafa menawi The Morphological Differences between Two species of Hookworms _____ A. duodenale N. americanus Size larger smaller ________________________________________________ Shape single curve, looks like C double curves, looks like S _____________________________________________ Mouth 2 pairs of ventral teeth 1peir of ventral cutting plates _______________________________________________ Copulatory circle in shape oval in shape Bursa (a top view) (a top view) ________________________________________________ Copulatory 1pair with separate 1pair of which unite to form spicule endings a terminal hooklet ________________________________________________ caudal spine present no ________________________________________________ vulva position post-equatorial pre-equatorial
parasite lab by l.wafa menawi Life Cycle 1. Final host: man 2. Inf. Stage: Larva 3 or filariform larva 3. Inf. Route: by skin 4. Food: blood and tissue fluid 5. Site of inhabitation: small intestine 6. Life span: Ad 15years, Na 3-7years 7. Blood-lung migration: skin, cavum, right heart, lungs
parasite lab by l.wafa menawi Life cycle of hookworm
parasite lab by l.wafa menawi
Adult worms live in the small intestine and female lay eggs a day over 5 years Eggs are passed with the feces Larvae develop outside the body and molt twice The filariform or L3 larvae move to the surface in search for a host If they come into contact with the host they penetrate the skin, enter blood vessels and leave the circulatory system into the alveoli The larvae move up the trachea into the esophagus, are swallowed and finally reach the intestine, where they molt twice more before they reach maturity
parasite lab by l.wafa menawi Pathogenesis and Clinical Manifestations 1. Larval migration (1) Dermatitis, known as "ground itch" or "stool poison".The larvae penetrating the skin cause allergic reaction, petechiae 0r papule with itching and burning sensation. Scratching leads to secondary infection.
parasite lab by l.wafa menawi (2) pneumonitis (allergic reaction), Loeffier's syndrome: cough, asthma, low fever, blood-tinged sputum or hemoptysis, chest-pain, inflammation shadows in lungs under X-ray. These manifestations go on about 2 weeks.
parasite lab by l.wafa menawi 2. Adults in small intestine (1) Epigastric pain as that of a duodenal ulcer. (2) A large worm burden results in microcytic hypochromatic anemia (character manifestation). The symptoms are lassitude, edema, palpitation of the heart. In severe case, death may result from cardiac failure or physical exhaustion.
parasite lab by l.wafa menawi (3) Allotriophagy (orpica) is due to the lack of trace element iron. (4) Amenorrhea, sterility, abortion may take place in women. (5) Gastrointestinal bleeding (6) Infantile hookworm disease
parasite lab by l.wafa menawi Adults in intestinal mucosa
parasite lab by l.wafa menawi Diagnosis Criterion: 1. hemoglobin is lower than 120g/L in man, 110g/L in woman. 2. find hookworm egg Method: 1. saturated brine flotation technique 2. direct fecal smear 3. culture of larvae