When a parasitic nematode, such as a filariae, is still in the early stages of its larval life cycle, it is referred to as microfilaria. The mature parasites discharge these parasites into the hosts circulation. Therefore, these developing larvae are often discovered in an infected persons blood. An inspection of the blood smear is required for a microfilaria test to determine whether microfilariae are present in the blood. A microfilariae blood test is typically done at night, when microfilariae are most active. An earlobe, finger prick, or venous blood sample must be used for the microfilaria test process.