Question

The causative agent of filaria is
A. Wuchereria Bancrofti
B. Leishmania donovani
C. Plasmodium vivax
D. Trypanosoma gambiense

Answer 1

Hint: Filariasis refers to a parasitic disease. The filarioidea type roundworms are responsible for this infection. Filarial nematodes which are borne from mosquitoes are the causative agents of lymphatic filariasis (LF).

Complete answer:
Lymphatic filariasis is caused by Wuchereria Bancrofti. This disease majorly occurs in tropical and subtropical regions. The Culex mosquito is responsible for this disease. It attacks by infecting the lymphatic system thus impairing it. It blocks the lymphatic flow leading to the abnormal enlargement or swelling up of the body parts particularly limbs. This disease is also known as elephantiasis. It is responsible for causing severe pain, various disabilities and societal disgrace.
Annual preventive chemotherapy in combination with safe medications could end the infectious spread thus eliminating lymphatic filariasis. Individuals usually acquire this infection in the childhood stage where it starts damaging the lymphatic system in a hidden manner. However, in later stages it becomes painful and visible manifestations relating to the disease start to appear.
On the other hand, Leishmania donovani is responsible for causing visceral leishmaniasis which is also traditionally called as kala-azar while Plasmodium vivax is a parasitic protozoan which acts as a human pathogen. It is the causative agent of recurring malaria and Trypanosoma gambiense however causes African sleeping sickness.

Hence, the correct answer is option (A).

Note: Based on the presence of microfilariae in the peripheral blood, the filarial infected individuals could be defined as "microfilaraemia" or "amicrofilaremic". In the peripheral blood, microfilariae could be directly observed for diagnosing filariasis in microfilaraemia cases.