1. Hookworms

2. - is one of the major parasitic disease. At least two species of hookworms infect man, Necator americanus and Ancylostoma duodenale. They live in small intestine.

3. Adults of A. duodenaleAdults of N. americanus. Worldwide distribution. 22-26 ℃ is the optimal temperature for Ancylostoma duodenale development, 31-35 ℃ is suitable for Necator americanus Epidemiology

4. II. Life Cycle 1. Final host: man 2. Inf. Stage: filariform larva 3. Inf. Route: by skin for both or contaminated food and water for duodenale 4. Site of inhabitation: small intestine 5. Life span: Ad 15years, Na 3-7years

5. Life cycle of hookworm

6. III. 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.

7. Cont… (2) Pneumonitis (allergic reaction), Loeffler syndrome (cough, dyspnea, pleurisy, little or no fever, and eosinophilic pulmonary infiltrates), asthma, low fever, blood-tinged sputum or hemoptysis, chest-pain, inflammation shadows in lungs under X-ray. These manifestations go on about 2 weeks.

8. Cont.. Hypoproteinemia : Because of the clinically significant blood loss and the ingestion of serum proteins (manifests as weight-loss, anasarca, and edema). Blood loss: Inhibited host coagulation due to a series of anticoagulants

9. (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. (3) Gastrointestinal bleeding causing anemia –microcytic hypochromic. (4) Infantile hookworm disease- when the worm load is very high Sometimes children may develop a yellow green pallor known as “chlorosis”.A duodenale infection during infancy may be associated with diarrhoea, failure to thrive,and severe anemia. 2. Adults in small intestine

10. Adults in intestinal mucosa

11. Bleeding of intestinal wall

12. Iv. Diagnosis 1.Identifying the characteristic oval hookworm eggs in the feces. However the eggs of the 2 species are indistinguishable. 2. Blood examination reveals microcytic, hypochomic anemia occasionally with eosinophila. 3. Hypoalbuminemia seen in heavy infection.

13. Treatment Eradication of the worm is achieved by: 1.Albendazole (400 mg once for all age ) 2. 2. Mebedazole(100 mg twice a day for 3 days) 3.Pyrantel pamoate (11mg /kg once daily for 3 days) 4.Anemia is treated with oral iron therapy. 5.Severe anemia may require packed cell trasfusion.

14. Prevention Unified measures: 1.Sanitary disposal of night soil, 2.Individual protection, 3.Health education, 4.Cultivate hygienic habits, 5.Treat the patients and carriers.