Genetic diversity of Plasmodium falciparum among asymptomatic pregnant women on intermittent preventive treatment with sulfadoxine-pyrimethamine in Nigeria.

This study investigated the genetic diversity of Plasmodium falciparum among asymptomatic pregnant women on intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-Sp) in Osogbo, southwest Nigeria. Blood sample was obtained from consenting pregnant women attending antenatal clinics. Microscopy and Polymerase chain reaction (PCR) were employed to diagnose and analyse genetic diversity. Of the 301 samples, 53 (18%) and 83 (28%) were positive for P. falciparum by microscopy and PCR, respectively. Using the merozoite surface protein (msp)-1, msp-2, and glutamate-rich protein (glurp) genes of P. falciparum as polymorphic markers, the msp-1 gene showed nine alleles with R033 (66.7%) being predominant, followed by K1 (45.5%) and MAD20 (33.3%). The msp-2 gene had 16 alleles (eight each for FC27 and 3D7). The 3D7 alleles (82.1%) was significantly more than FC27 alleles (48.2%) (p = 0.0093). Nine alleles were detected with glurp gene, presenting with the highest monoclonal and the lowest polyclonal infection. The multiplicity of infection (MOI) of 1.5, 1.8, and 1.2 were obtained for msp-1, msp-2 and glurp genes. In light of the high P. falciparum genetic diversity among pregnant women on IPT-Sp in this study, additional strategies for preventing and controlling malaria in pregnancy might be required.

Attendee's awareness about preventive chemotherapy neglected tropical diseases (PC-NTD) control during the first world neglected tropical diseases day in Ekiti State, Nigeria.

BACKGROUND: The need to control Neglected Tropical Diseases (NTDs) and sustain progress towards elimination through mass administration of medicines requires substantial communal participation. This study, therefore, assessed the knowledge and perception of attendees' regarding NTDs and its control activities during the inaugural World NTD day event in Ekiti State, Nigeria. METHODOLOGY: A cross-sectional study involving the administration of pretested semi-structured questionnaires to consenting attendees at the Inaugural World NTD day event was conducted on the 30th January, 2020. The questionnaire collected data on attendee's demography, knowledge and awareness about NTDs and its control in Nigeria. Quantitative data were analysed using descriptive statistics in SPSS. 20.0 software and expressed as frequencies and percentages. However, qualitative data to support quantitative analysis were obtained using open-ended questionnaires and analysed thematically. PRINCIPAL FINDINGS/CONCLUSION: A total of 309 attendees comprising 167 (54.0%) females, and 142 (46.0%) males participated in this study. By age groupings, majority 206 (66.7%) were within 15-25 years. 167 (54.8%) of the attendees have not heard about NTDs before, whereas 77(35.0%) have heard about NTDs through the advertisement of the event. 181(63.3%) were aware of ongoing NTD control programs in schools and communities. Also, 246 (83.4%) of them have not taken or do not know anyone that has taken drugs donated in schools or communities. The number of attendees 41(13.3%) who incorrectly classified malaria as NTDs is higher than those who recognized onchocerciasis 36 (11.7%) and worm infections 34(11.0%) as NTDs (p>0.05). This study has shown that awareness and knowledge about NTDs control activities in Ekiti State is low, thus justifying the event as an awareness day for addressing NTDs. Public enlightment and regular promotional activities such as media engagement will raise the public appreciation and participation in NTDs control activities.

Ficolin-2 levels and genetic polymorphisms of FCN2 in malaria.

Human ficolin-2 (L-ficolin; FCN2) is a serum protein binding to sugar moieties of different human micro-pathogens forcing phagocytosis. Here, we investigate the clinical significance of FCN2 in African children with either mild or severe malaria (n = 130 and n = 108, respectively) from Gabon by analyzing three promoter SNPs (-986G>A, -602G>A, and -4A>G) and one single nucleotide polymorphisms (SNP) in exon 8 (+6424G>T) using quantitative TaqMan, real-time polymerase chain reaction (PCR). In addition, we measured the ficolin-2 plasma levels at two time points: on admission (t(0), acute disease) and 4 weeks after treatment (t(1), healthy phase). Comparison of ficolin-2 plasma levels shows that ficolin-2 concentration is highest during acute severe disease. In addition, we determined polymorphisms in the promoter and all coding regions of FCN2 in 40 Gabonese. Linkage disequilibrium data revealed polymorphic allelic combination patterns in the FCN2 promoter region; strong allelic combinations at -986 and -4, and -557 and -64 were found. No FCN2 promoter haplotypes were significantly distributed between mild and severe cases.

Molecular surveillance of drug-resistant Plasmodium falciparum in two distinct geographical areas of Nigeria.

Drug resistance against P. falciparum has been recognized as the crucial obstacle to curbing mortality and morbidity from malaria. We therefore determined the baseline distribution of pfcrt and pfmdr1 genes associated with resistance to chloroquine and pfdhfr gene associated with resistance to pyrimethamine in P. falciparum isolates collected from two geographically distinct areas of Nigeria. We use RT-PCR assays and sequencing to determine the prevalence of these mutations. The combined prevalence of pfcrt T76 mutation in the two sites was 92.3% with 86% from Osogbo compared to 93% from Lafia. Sequencing analysis of the (Pfcrt) K76T haplotype (amino acids 72-76) revealed CVIET as the only resistance haplotype present in the two areas. The frequency of pfmdr1 polymorphisms was higher in Lafia (39%) compared to that in Osogbo (35%) and the combined prevalence from the two sites was 45.5%. The prevalence of the pfdhfr triple mutant alleles was high in both locations. The Osogbo vs Lafia prevalence for pfdhfr mutations was 84% vs 91%, 88% vs 87% and 96% vs 96% for I51, R59 and N108, respectively. None of the samples from the two locations had the T108 mutation. The combined prevalence of pfcrt and pfmdr1 in Osogbo and Lafia was 44.2% with a risk ratio of 0.4164 while the combined prevalence of pfcrt, pfmdr1 and pfdhfr was 40.4% with a risk ratio of 1.081. These results strongly suggest the widespread distribution of CQ and pyrimethamine resistance without any marked distinction between the two locations.

Comparison of PCR-based detection of Plasmodium falciparum infections based on single and multicopy genes.

PCR-based assays are the most sensitive and specific methods to detect malaria parasites. This study compared the diagnostic accuracy of three PCR-based assays that do not only differ in their sequence target, but also in the number of copies of their target region, for the detection of Plasmodium falciparum in 401 individuals living in a malaria-endemic area in Nigeria. Compared to a composite reference generated from results of all the 3 PCR assays, the stevor gene amplification had a sensitivity of 100% (Kappa = 1; 95% CI = 1.000-1.000), 83% (Kappa = 0.718; 95% CI = 0.648-0.788) by SSUrRNA gene PCR and 71% (Kappa = 0.552; 95% CI = 0.478-0.627) by the msa-2 gene amplification. Results from this study indicate that the stevor gene amplification is the most sensitive technique for the detection of P. falciparum. This assay may be an important reference standard, especially when a confirmatory technique with high sensitivity and specificity is needed for ruling out P. falciparum infection.