High prevalence of dihydrofolate reductase gene mutations inPlasmodium falciparumparasites among pregnant women in Nigeria after reported use of sulfadoxine-pyrimethamine

Abstract

This study assesses the prevalence of asymptomatic Plasmodium falciparum parasitemia positivity and P. falciparum dihydrofolate reductase (pfdhfr) mutations in parasite isolates among pregnant women in Southwest Nigeria. Plasmodium falciparum parasitemia was confirmed by microscopy and nested PCR in 200 pregnant women attending antenatal care. The prevalence of pfdhfr polymorphisms was determined by direct sequencing of the gene fragments containing the C50R, N51I, C59R, S108N, and I164L mutations. Information on the use of antimalarial drugs and methods applied to prevent malaria were obtained by a questionnaire. The prevalence of asymptomatic P. falciparum infection was 30% (60/200). The frequency of the pfdhfr triple-mutant alleles (N51I, C59R, and S108N) was 63% (38/60); none of the isolates carried the I164L mutation. Among the investigated pregnant women, 40% used un-prescribed antimalarials such as dihydroartemisinin (18%), chloroquine (14%) or pyrimethamine (9%), while only 20.5% used sulfadoxine-pyrimethamine for prevention and 39.5% did not use any drug. The prevalence of P. falciparum parasitemia (37%) was higher among pregnant women who had not taken any antimalarial drugs. A significant difference in the prevalence of the pfdhfr triple-mutant alleles was observed among women who took SP (90%) compared to those who did not take any drug (82%) and women who took dihydroartemisinin (67%) p = 0.007). Poor adherence to the World Health Organisation (WHO) strategies for malaria prevention among pregnant women was observed in addition to high prevalence of pfdhfr mutations. These findings underline the need to improve control of malaria among pregnant women in the study area.

Sub-microscopic Plasmodium falciparum infections in matched peripheral, placental and umbilical cord blood samples from asymptomatic Congolese women at delivery

“…The SP doses have not reduced the MOI. This might result from the carriage of SP-resistant parasites in such women as suggested earlier (Moussiliou et al, 2013, Koukouikila-Koussounda et al, 2015Ojurongbe et al, 2018).…”

A snapshot of the prevalence of dihydropteroate synthase-431V mutation and other sulfadoxine-pyrimethamine resistance markers in Plasmodium falciparum isolates in Nigeria

“…Similar findings have been reported in Nigeria and other countries across SSA [ 17 , 53 ]. This suggests that the quadruple mutations are already fixed in these populations [ 18 , 32 , 54 ]. Indications from other studies however revealed that the protective effect of SP-IPTp remains intact, regardless of the high prevalence of this quadruple Pfdhfr - Pfdhps mutant [ 2 , 55 ].…”

Epidemiology of Malaria in Pregnancy and Associated Risk Factors in Nigeria: a Review

“…In a study conducted in Nigeria to determine the prevalence of positive asymptomatic Plasmodium falciparum parasitemia amongst pregnant women, it was reported that 30% (60/200) of the recruited women has asymptomatic P. falciparum infection [32]. Malaria susceptibility rises throughout pregnancy, making pregnant women a major parasite reserve in the population.…”

“…In south western Nigeria, dhfr (S108N), and dhps (K540E) resistant genes of plasmodium parasite have been observed among isolates from children, pregnant women and other adult cohorts [63]. Another report in Nigeria recorded a very high frequency of the Plasmodium falciparum dhfr triple-mutant alleles (N51I, C59R, and S108N) at 63% (38/60) while none of the isolates carried the I164L mutation [32]. In another study, the frequency of mutations at S436A, A437G, A581G and A613S positions in dhps gene of plasmodium parasite was 82.1% (23/28), 96.4% (27/28), 71.4% (20/28) and 71.4% (20/28) respectively having reported in the same study that the triple mutations in dhfr gene was almost fixed; S108N (100%), N51I (93%) and C59R (93%) [64].…”