African Journal of Biotechnology Vol. 5 (18), pp. 1655-1662, 18 September 2006, © 2006 Academic Journals
Polymorphism and antigenic variation are important biological survival strategies of malaria parasites
determining the episode, outcome and implications of treatment interventions. In P. falciparum,
polymorphic antigens are associated with the asexual blood-stage; merozoite surface protein 2 (MSP2).
The MSP2 genes have been invaluable in post-treatment discrimination of parasite resurgence from
new infection, especially in high transmission areas. We performed polymerase chain reaction (PCR) on
DNA extracted from blood samples of 141 malaria-infected infants, followed by restriction fragment
length polymorphism (RFLP) of PCR products. The findings showed multiplicity of infections of single
to six infections with an average of 2.58 infections per patient. Single infections of either 3D7 or FC27
allelic families of the MSP2 gene occurred in 51 patients (50.5%) out of all PCR-RFLP successful
samples (n = 101). Out of 15 (10.6%) follow up samples with resurgent parasitaemia, 3 (20%) samples
had recrudescent infections while 12 (80%) had variable results. Our findings provide an insight on the
prevalence of the genetic determinants of suphadoxine-pyrimethamine (SP) resistance in Mlimba during
the study period, and in the face of rapidly spreading resistance, calls for the periodic surveillance in
order to timely detect early warning signal of the deteriorating SP cure rate.