Assessing to What Extent Dhps-431V Mutation May Influence the Protective Efficacy of IPTp-SP

Overview

Malaria in pregnancy (MiP) continues to be a significant public health issue, particularly in sub-Saharan Africa. The coverage of pregnant women with three or more doses of intermittent preventive treatment using sulphadoxine-pyrimethamine (IPTp-SP) is recommended to prevent risks associated with MiP in moderate-to-high transmission settings. Evidence has recently become available supporting the emergence of a novel Pfdhps-431V mutation in Nigeria. This new mutation may further confound the existing SP-resistance; thus, the intended follow-on project aims to assess the influence of Pfdhps-431V mutation on the protective efficacy of SP during pregnancy. The aims are to detect P. falciparum positivity at delivery and pregnancy outcome in participants who must have received three or more doses of IPTp\_SP. We will attempt to check the presence of existing and new Pfdhps/Pfdhfr mutations in the samples positive for P. falciparum using a quantitative PCR (qPCR). The prevalence of novel Pfdhps-431V mutant and other Pfdhps/Pfdhfr resistance alleles among the study population will be estimated. The significance of the resistance genes on the efficacy of SP will be described by looking at its associations with the reported IPTp use, P. falciparum infection, maternal anaemia, low birth weight, and preterm delivery.

Malaria in pregnancy (MiP) is considered a major public health issue with substantial risks for mothers and their babies. Intermittent preventive treatment in pregnancy using sulphadoxine-pyrimethamine (IPTp-SP) is adopted as a part of antenatal care (ANC) to prevent malaria and reduce the risk associated with MiP. However, SP-resistance is increasing with the emergence of Plasmodium falciparum dihydropteroate synthase (Pfdhps) and P. falciparum dihydrofolate reductase (Pfdhfr) resistant genes challenging the benefits and effectiveness of IPTp-SP. Still, evidence has become available supporting the emergence of a novel Pfdhps-I431V mutation. The I431V mutation is found only in West and Central African countries, however, its impact on SP resistance has not been evaluated. We are hypothesizing that the new mutation may confound the existing SP-resistance resulting in an apparent reduction in the protective effect of SP during pregnancy within the region. The study will recruit adult pregnant women and will assess the presence of malaria infection at delivery. The study will seek new mutations in vivo using full sequencing. This molecular tool will also be used to look at the prevalence of novel Pfdhps-431V mutation among pregnant women undergoing monthly IPTp-SP. Attempts will be made to re-evaluate the prevalence of other Pfdhps and Pfdhfr resistance alleles among the study population. The significance of the resistance genes on the protective efficacy of SP will be described. The present study is an observational study to be conducted among all booked pregnant women. The pregnant women must have received at least three therapeutic doses of sulphadoxine-pyrimethamine as part of routine antenatal care (ANC) before delivery. sion and Pregnant women who consented to participate will be tested for the presence of malaria parasite during the third trimester and at delivery. 80-100 µL blood samples will be saved as dried blood spot on Whatman® filter paper from the individual with P. falciparum malaria positivity Antenatal care (ANC) contact schedule with proposed timelines for implementation of malaria in pregnancy interventions designed by WHO will be followed in enrolling subjects from 26 weeks of pregnancy. The study will be conducted at the antenatal