INTRODUCTION: Accumulating resistance to Sulphadoxine-Primethamine-intermittent preventive treatment in pregnancy (SP-IPTp) is partly attributed to its failure to improve malaria outcomes in pregnancy. As resistance continues to accumulate, ineffectiveness of IPTp-SP is inevitable. Routine monitoring of parasite strains for the effectiveness of antimalarial is therefore crucial, in disease-endemic areas, for early detection of reduced parasite susceptibilities and emerging resistance to the drugs.
AIM: This cohort study assessed the current status of pfdhps and pfdhfr resistance markers to SP and the effectiveness of IPTp-SP in Pregnant women.
METHODS: Venous blood was collected and malaria parasite infective determined by blood mRDT and light microscopy. DNA was extracted by Chelex-100 method and nested PCR for P. falciparium detection. Single Nucleotide Polymorphism genotyping for Pfdhps and Pfdhfr resistant markers in positive P. falciparum samples was then undertaken by nested PCR followed by allele-specific restriction analysis (ASRA).
RESULTS: The proportion of malaria parasite infected from 300 pregnant women determined by microscopy, mRDT and PCR was 12.9%, 16.4% and 29.4% respectively and a very low-density infection, averaging 271 parasites per microliter of blood. The proportion of infection was significantly reduced in IPTp-SP users compared to non-users with a significant association (p=0.001) between the malaria parasite status by microscopy and IPTp-SP dosage.
ASRA shows that this population harbour 100% mutant alleles for dhfr S108N, 53.9% dhps A581G mutants while dhps K540E substitution was absent.
CONCLUSION: These results suggest an increase prevalence of these molecular markers associated with P. falciparum resistance to SP in Mutengene with implication for IPTp-SP.