UKMLA PLAB AMC USMLE Prometric MCQ

Question Number 0932
Question:
A 30yr old man visiting Africa developed high grade fever associated with chills and rigors. The doctor there diagnosed it to be malaria and the man was treated with chloroquine. The patient responded to the medication and became asymptomatic.He immediately returned home to USA and after about 4 wk. again developed high grade fever associated with chills and rigors. The man was diagnosed to have a recurrence of malaria. The most probable cause for his recurrence is:

a) re-infection by the organism
b) survival of the exo-erythrocytic phase of the parasite
c) survival of a dormant form of the parasite in his bone marrow
d) survival of the erythrocytic phase of the parasite
e) chloroquine is not effective against malaria