Question

1. Write the scientific names of the two species of filarial worms causing filariasis.     [1]
2. How do they affect the body of infected persons?     [1]
3. How does the disease spread?     [1]

Answer 1

1. Wuchereria bancrofti and Brugia malayi.
2. The parasites inhabit and damage the lymphatic vessels and nodes, causing lymphatic dysfunction that leads to lymphoedema, elephantiasis (chronic swelling and skin/tissue thickening) and hydrocele, with recurrent painful inflammatory attacks.
3. Lymphatic filariasis is transmitted when an infected mosquito (e.g., Culex, Anopheles, or Aedes species) bites a person and deposits infective larvae that develop into adult worms in the human lymphatics; infected humans then serve as the reservoir for further mosquito-borne transmission.