Ascariasis_Presentation_Dr_R_N_Rani[1].pptx

1. Presented by: Dr R N Rani, BNYS MD
Department of Microbiology
Ascariasis (Ascaris lumbricoides)

2. Introduction
 Ascariasis is an intestinal infection caused by the roundworm
Ascaris lumbricoides.
 It is one of the most common helminthic infections,
especially in tropical and subtropical regions.
 Transmission occurs via ingestion of infective eggs through
contaminated food or water.

3. Taxonomy and Morphology
 Phylum: Nematoda
 Class: Secernentea
 Order:Ascaridida
 Genus:Ascaris
 Species: lumbricoides
 Adult worms are large, creamy-white, cylindrical worms.
 Males: 15–30 cm long with curved posterior end.
 Females: 20–35 cm long.
 Eggs: Fertilized and unfertilized types with thick shell and
mammillated surface.

4. Morphology

5. Distribution and Epidemiology
 • Common in tropical and subtropical areas with poor
sanitation.
 • More prevalent among children.
 • Transmission via fecal contamination of soil, food, and
water.
 • Eggs can survive in moist soil for years.

6. Life Cycle
 1. Infective eggs are ingested.
 2. Larvae hatch in intestine and migrate via bloodstream to
lungs.
 3.After maturation in lungs, larvae ascend trachea, are
swallowed, and mature into adults in intestine.
 4. Females produce thousands of eggs passed in feces.
 Total cycle duration: 60–75 days.

8. Pathogenesis and Clinical Features
 • Light infections: Often asymptomatic.
 • Heavy infections:Abdominal pain, malnutrition, growth
retardation.
 • Pulmonary phase: Cough, eosinophilia (Löffler’s
syndrome).
 • May cause intestinal obstruction in children.

9. Complications
 • Intestinal obstruction (especially in children)
 • Biliary or pancreatic duct obstruction
 • Appendicitis or perforation due to migration
 • Nutritional deficiency due to malabsorption.

10. Intestinal obstruction

11. Laboratory Diagnosis
 • Stool microscopy: Detection of characteristic eggs.
 • Concentration techniques (Kato-Katz, formalin-ether).
 • Imaging: Ultrasonography or X-ray in complications.
 • Serology rarely needed.

12. Treatment
 • Albendazole 400 mg single dose (preferred)
 • Mebendazole 100 mg twice daily for 3 days
 • Pyrantel pamoate as an alternative.
 • Treat all family members simultaneously.

13. Prevention and Control
 • Improve sanitation and hygiene.
 • Proper disposal of feces.
 • Washing of vegetables and fruits.
 • Regular deworming in endemic areas.
 • Health education to communities.

14. Summary
 • Ascariasis is caused by Ascaris lumbricoides.
 • Transmitted by ingestion of embryonated eggs.
 • Life cycle involves larval migration through lungs.
 • Diagnosis by stool microscopy.
 • Prevention: Sanitation and deworming programs.

15. References
 1. Paniker’sTextbook of Medical Parasitology, 8th Ed.
 2. CDC – Ascariasis Fact Sheet.
 3.WHO Guidelines for Control of Soil-transmitted
Helminths.