Other Definitions
ascaris lumbricoides (dict)
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Ascaris LumbricoidesAscaris lumbricoides is a human parasitic roundworm, which causes the disease of ascariasis. Ascaris lumbricoides is the largest nematode (roundworm) which parasitizes the human intestine. Adult females are 20 to 35 cm in length, and adult males 15 to 30 cm. Life Adult worms live in the lumen of the small intestine. A female may produce approximately 200,000 eggs per day, which are passed with the feces. Unfertilized eggs may be ingested but are not infective. Fertile eggs embryonate and become infective after 18 days to several weeks, depending on the environmental conditions (optimum: moist, warm, shaded soil). After infective eggs are swallowed, the larvae hatch, invade the intestinal mucosa, and are carried via the portal, then systemic circulation to the lungs. The larvae mature further in the lungs (10 to 14 days), penetrate the alveolar walls, ascend the bronchial tree to the throat, and are swallowed. Upon reaching the small intestine, they develop into adult worms. Between 2 and 3 months are required from ingestion of the infective eggs to oviposition by the adult female. Adult worms can live 1 to 2 years. Symptoms Ascaris infection may be mild in nature. With heavy infection though, abdominal cramping is seen. Diagnosis - Stool examination for eggs
- Sputum examination for presence of larvae
- Increased esoinophil count.
Distribution Ascaris lumbricoides is distributed worldwide, with highest prevalence in tropical and subtropical regions, and areas with inadequate sanitation. It occurs in rural areas of the southeastern United States. Treatment
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