Question

Which of the following blood group antigens serves as receptor for Plasmodium vivax?

• A. Duffy
• B. ABO
• C. Kell
• D. Rh

Hint:

Duffy negative red cells resist P. vivax invasion.

Answer 1

The Correct Option is A

This question checks which surface marker on the red blood cell membrane the malaria parasite Plasmodium vivax latches onto before entering the cell.

1. Duffy: This antigen, part of the Duffy antigen receptor for chemokines, acts as the attachment point P. vivax needs to invade a red cell. Without it, the merozoite cannot get in.
2. ABO: This system matters for transfusion matching, not for vivax invasion.
3. Kell: Used mainly in transfusion and antenatal antibody screening, it plays no part here.
4. Rh: Important for Rh disease of the newborn and transfusions, but not for this parasite's entry.

People who are Duffy negative, a trait seen widely in West Africa, resist vivax infection since the parasite has nothing to bind to.

Let's summarize:

• The Duffy antigen is the red cell receptor that P. vivax needs for invasion.
• Duffy negative individuals are naturally protected from this species of malaria.

So the correct answer is Duffy.