Parasitic infections

Question 1

How is Filariasis spread?

Answer 1

By blood feeding black flies and mosquitos

Question 2

What is Elephantiasis and what does Elephantiasis indicates?

Answer 2

Elephantiasis is oedema with thickening of skin and underlying tissue.
It occurs when parasite Filariae enters the lymphatics

Question 3

What test is done for diagnosis of Filariasis? Describe the procedure and the things to take note of.

Answer 3

Finger prick test - draws blood from the capillaries of the fingertips.
Blood must be drawn at appropriate times, reflecting the feeding time of the vector insects. For M. bancrofti, vector is a mosquito, and night time is favoured for the test. For Lao lao, vector is the deer fly, and favoured time is in the day time.
But some parasitic worms do not have their microfilariae residing in the blood, but on skin. skin snipping will be used for these diagnosis.

Question 4

What are the respective functions of the thick and thin blood film taken to test for Malaria?

Answer 4

The thick blood film is used to detect for the presence of parasites. (Larger amount of blood sample)
The thin blood film is used to identify the species of the Plasmodium causing the infection.

Question 5

Which species of Plasmodium is a man infected with if he presented with Malaria several months later again, without re-exposure to a mosquito?

Answer 5

P. Vivax or P. Ovale