Dracunculus medinensis

 

6.2v  Habitat

     •Adults – in the subcutaneous tissues and intramuscular connective tissue especially around the ankle

o   Male- dies after copulation.

·      Larva-First stage larvae – in the ulcers and blisters

·        Infective filariform larvae – in the hemoceole of Cyclops

 

v Morphology

·        Adults: -White smooth surface and thread like

o   Male short, coiled posterior end

o   Female: the longest nematode of man

o   Larvae: rounded anterior end and long and pointed tail.

v Life cycle & transmission

v  Transmission–swallowing water containing crustaceans belonging to the genus Cyclops

·        Dog -reservoir host.

v  Life cycle of Dracunculus medinensis

v  Pathology and clinical features

·        As the female worm comes to the surface of the skin;

·        There will be a toxic / allergic tissue reaction,

·        Itching, pain, reddening of the skin,

·        Blister formation, urticaria, fever, nausea, and vomiting.

·        20 infection of the ulcers is common;

·        Serious infection of deeper body tissues  Cellulites,

·        If joint is involved - Arthritis.

v  Laboratory diagnosis

·        Worms cab be seen beneath the skin surface,

·        Larvae can be demonstrated by dropping water at the site of ulcer.

v  Relevance to Ethiopia

o   Restricted to Ethio-Sudan boarder; Gambella area.

o   In south- a mild spotty coverage.

v  Prevention and control

·        Installing a piped water supply,

·        Destroy the Cyclops by using chemicals:

·        Organ phosphorus, or Chlorine, etc

·        Avoid drinking infected water or filter using nylon or boiling,

·        Covering the blister with a water proof dressing.

·        Summary on Periodicity and main vector of filarial worms