Evidence on sulfadoxine-pyrimethamine resistance molecular markers from India: interpret with caution.

BACKGROUND: Sulfadoxine-pyrimethamine (SP), as a partner to artesunate as ACT is the treatment of choice for uncomplicated P. falciparum infections in the majority of India and SP-resistance has a potential to lead to ACT failure. In the lack of robust surveillance of therapeutic efficacy of SP, validate molecular markers of SP-resistance offer a hint of failing SP. However, studies reporting these validated markers often suffer from certain pitfalls that warrant a careful interpretation. MAIN BODY: Critical analyses of the results and their reported interpretations from a recent study and other studies conducted on the WHO-validated molecular markers of SP-resistance in India were analysed and the main problems with studying and reporting of these markers are presented here. It was noted that almost all studies analysed flawed either on the usage, estimation and/or interpretation of the standardized classification of the studies SP mutations. These flaws not only impart spatiotemporal incomparability of the published data but also have the potential of being misunderstood and wrongly translated. CONCLUSION: Based on this universal problem in studying, reporting and interpreting the data from the studies on molecular markers of SP-resistance, it is stressed that the future studies should be conducted with utmost caution so that robust evidence may be generated and correctly translated to policy.

Field testing of user-friendly perennial malaria chemoprevention packaging in Benin, Côte d'Ivoire and Mozambique.

BACKGROUND: Perennial malaria chemoprevention (PMC) aims to protect children at risk from severe malaria by the administration of anti-malarial drugs to children of defined ages throughout the year. Sulfadoxine-pyrimethamine (SP) has been widely used for chemoprevention in Africa and a child-friendly dispersible tablet formulation has recently become available. METHODS: This qualitative non-interventional observational study was conducted in Benin, Côte d'Ivoire, and Mozambique between February and June 2022. Prototype blister packs, dispensing boxes and job aids designed to support dispersible SP deployment for PMC were evaluated using focus group discussions (FGD) and semi-structured in-depth individual interviews (IDI) with health authorities, health personnel, community health workers (CHWs) and caregivers. The aim was to evaluate knowledge and perceptions of malaria and chemoprevention, test understanding of the tools and identify gaps in understanding, satisfaction, user-friendliness and acceptability, and assess the potential role of CHWs in PMC implementation. Interviews were transcribed and imported to ATLAS.ti for encoding and categorization. Thematic content analysis used deductive and inductive coding with cross-referencing of findings between countries and participants to enrich data interpretation. Continuous comparison across the IDI and FGD permitted iterative, collaborative development of materials. RESULTS: Overall, 106 participants completed IDIs and 70 contributed to FGDs. Malaria was widely recognised as the most common disease affecting children, and PMC was viewed as a positive intervention to support child health. The role of CHWs was perceived differently by the target groups, with caregivers appreciating their trusted status in the community, whereas health authorities preferred clinic-based deployment of PMC by health professionals. Empirical testing of the prototype blister packs, dispensing boxes and job aids highlighted the context-specific expectations of respondents, such as familiar situations and equipment, and identified areas of confusion or low acceptance. A key finding was the need for a clear product identity reflecting malaria. CONCLUSION: Simple modifications profoundly affected the perception of PMC and influenced acceptability. Iterative quantitative investigation resulted in PMC-specific materials suited to the local context and socio-cultural norms of the target population with the aim of increasing access to chemoprevention in children most at risk of severe malaria.

A quasi-experimental study to estimate effectiveness of seasonal malaria chemoprevention in Aweil South County in Northern Bahr El Ghazal, South Sudan.

BACKGROUND: Seasonal malaria chemoprevention (SMC) is an effective intervention to prevent malaria in children in locations where the burden of malaria is high and transmission is seasonal. There is growing evidence suggesting that SMC with sulfadoxine-pyrimethamine and amodiaquine can retain its high level of effectiveness in East and Southern Africa despite resistance concerns. This study aims to generate evidence on the effectiveness of SMC when delivered under programmatic conditions in an area with an unknown anti-malarial drug resistance profile in the Northern Bahr el-Ghazal region of South Sudan. METHODS: A non-randomized quasi experimental study was conducted to compare an intervention county with a control county. Five monthly SMC cycles were delivered between July and November 2022, targeting about 19,000 children 3-59 months old. Data were obtained from repeated cross-sectional household surveys of caregivers of children aged 3-59 months using cluster sampling. Wave 1 survey took place in both counties before SMC implementation; Waves 2 and 3 took place after the second and fourth monthly SMC cycles. Difference-in-differences analyses were performed by fitting logistic regression models with interactions between county and wave. RESULTS: A total of 2760 children were sampled in the study across the three survey waves in both study counties. Children in the intervention arm had 70% lower odds of caregiver-reported fever relative to those in the control arm during the one-month period prior to Wave 2 (OR: 0.30, 95% CI 0.12-0.70, p = 0.003), and 37% lower odds in Wave 3 (OR: 0.63, 95% CI 0.22-1.59, p = 0.306) after controlling for baseline difference between counties in Wave 1. Odds of caregiver-reported RDT-confirmed malaria were 82% lower in the previous 1-month period prior to Wave 2 (OR: 0.18, 95% CI 0.07-0.49, p = 0.001) and Wave 3 (OR: 0.18, 95% CI 0.06-0.54, p = 0.003). CONCLUSION: These results show high effectiveness of SMC using SPAQ in terms of reducing malaria disease during the high transmission season in children 3-59 month. Despite the promising results, additional evidence and insights from chemoprevention efficacy cohort studies, and analyses of relevant resistance markers, are required to assess the suitability of SMC for this specific context.

Implementation of post-discharge malaria chemoprevention (PDMC) in Benin, Kenya, Malawi, and Uganda: stakeholder engagement meeting report.

A Stakeholder engagement meeting on the implementation of post-discharge malaria chemoprevention (PDMC) in Benin, Kenya, Malawi, and Uganda was held in Nairobi, Kenya, on 27 September 2023. Representatives from the respective National Malaria Control Programmes, the World Health Organization (WHO) Geneva, Africa Regional and Kenya offices, research partners, non-governmental organizations, and the Medicines for Malaria Venture participated. PDMC was recommended by the WHO in June 2022 and involves provision of a full anti-malarial treatment course at regular intervals during the post-discharge period in children hospitalized with severe anaemia in areas of moderate-to-high malaria transmission. The WHO recommendation followed evidence from a meta-analysis of three clinical trials and from acceptability, delivery, cost-effectiveness, and modelling studies. The trials were conducted in The Gambia using monthly sulfadoxine-pyrimethamine during the transmission season, in Malawi using monthly artemether-lumefantrine, and in Kenya and Uganda using monthly dihydroartemisinin-piperaquine, showing a significant reduction in all-cause mortality by 77% (95% CI 30-98) and a 55% (95% CI 44-64) reduction in all-cause hospital readmissions 6 months post-discharge. The recommendation has not yet been implemented in sub-Saharan Africa. There is no established platform for PDMC delivery. The objectives of the meeting were for the participating countries to share country contexts, plans and experiences regarding the adoption and implementation of PDMC and to explore potential delivery platforms in each setting. The meeting served as the beginning of stakeholder engagement within the PDMC Saves Lives project and will be followed by formative and implementation research to evaluate alternative delivery strategies in selected countries. Meeting highlights included country consensus on use of dihydroartemisinin-piperaquine for PDMC and expansion of the target group to "severe anaemia or severe malaria", in addition to identifying country-specific options for PDMC delivery for evaluation in implementation research. Further exploration is needed on whether the age group should be extended to school-age children.

Seasonal Malaria Chemoprevention Drug Levels and Drug Resistance Markers in Children With or Without Malaria in Burkina Faso: A Case-Control Study.

BACKGROUND: Despite scale-up of seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine and amodiaquine (SP-AQ) in children 3-59 months of age in Burkina Faso, malaria incidence remains high, raising concerns regarding SMC effectiveness and selection of drug resistance. Using a case-control design, we determined associations between SMC drug levels, drug resistance markers, and presentation with malaria. METHODS: We enrolled 310 children presenting at health facilities in Bobo-Dioulasso. Cases were SMC-eligible children 6-59 months of age diagnosed with malaria. Two controls were enrolled per case: SMC-eligible children without malaria; and older (5-10 years old), SMC-ineligible children with malaria. We measured SP-AQ drug levels among SMC-eligible children and SP-AQ resistance markers among parasitemic children. Conditional logistic regression was used to compute odds ratios (ORs) comparing drug levels between cases and controls. RESULTS: Compared to SMC-eligible controls, children with malaria were less likely to have any detectable SP or AQ (OR, 0.33 [95% confidence interval, .16-.67]; P = .002) and have lower drug levels (P < .05). Prevalences of mutations mediating high-level SP resistance were rare (0%-1%) and similar between cases and SMC-ineligible controls (P > .05). CONCLUSIONS: Incident malaria among SMC-eligible children was likely due to suboptimal levels of SP-AQ, resulting from missed cycles rather than increased antimalarial resistance to SP-AQ.

Geographical emergence of sulfadoxine-pyrimethamine drug resistance-associated P. falciparum and P. malariae alleles in co-existing Anopheles mosquito and asymptomatic human populations across Cameroon.

Malaria molecular surveillance remains critical in detecting and tracking emerging parasite resistance to anti-malarial drugs. The current study employed molecular techniques to determine Plasmodium species prevalence and characterize the genetic diversity of Plasmodium falciparum and Plasmodium malariae molecular markers of sulfadoxine-pyrimethamine resistance in humans and wild Anopheles mosquito populations in Cameroon. Anopheles mosquito collections and parasitological survey were conducted in villages to determine Plasmodium species infection, and genomic phenotyping of anti-folate resistance was accomplished by sequencing the dihydrofolate-reductase (dhfr) and dihydropteroate-synthase (dhps) genes of naturally circulating P. falciparum and P. malariae isolates. The malaria prevalence in Elende was 73.5% with the 5-15 years age group harboring significant P. falciparum (27%) and P. falciparum + P. malariae (19%) infections. The polymorphism breadth of the pyrimethamine-associated Pfdhfr marker revealed a near fixation (94%) of the triple-mutant -A16I51R59N108I164. The Pfdhps backbone mediating sulfadoxine resistance reveals a high frequency of the V431A436G437K540A581A613 alleles (20.8%). Similarly, the Pmdhfr N50K55L57R58S59S114F168I170 haplotype (78.4%) was predominantly detected in the asexual blood stage. In contrast, the Pmdhps- S436A437occured at 37.2% frequency. The combined quadruple N50K55L57R58S59S114F168I170_ S436G437K540A581A613 (31.9%) was the major circulating haplotype with similar frequency in humans and mosquitoes. This study highlights the increasing frequency of the P. malariae parasite mostly common in asymptomatic individuals with apparent P. falciparum infection. Interventions directed at reducing malaria transmission such as the scaling-up of SP are favoring the emergence and spread of multiple drug-resistant alleles between the human and mosquito host systems.

Effects of maternal antenatal treatment with two doses of azithromycin added to monthly sulfadoxine-pyrimethamine for the prevention of low birth weight in Burkina Faso: an open-label randomized controlled trial.

BACKGROUND: Exposure during pregnancy to malaria and sexually-transmitted infections is associated with adverse birth outcomes including low birth weight (LBW). This study aimed at assessing if the adjunction of two doses of azithromycin to sulfadoxine-pyrimethamine for the intermittent preventive treatment of malaria in pregnancy can reduce LBW. METHODS: A two parallel-groups, open-label randomized controlled trial involving pregnant women (16 to 35 years of age and 12 to 24 weeks of gestation as confirmed by last menstrual period or fundal height) was conducted in rural Burkina Faso. Women were assigned in a 1:1 ratio either to use azithromycin (1 g daily for 2 days) during the second and third trimesters of pregnancy plus monthly sulfadoxine-pyrimethamine (1500/75 mg) (SPAZ) (intervention) or to continue using a monthly sulfadoxine-pyrimethamine (1500/75 mg) (SP) (control). Primary outcome was a LBW (birth weight measured within 24 h after birth < 2500 g). Secondary outcomes including stillbirth, preterm birth or miscarriage are reported together with safety data. RESULTS: A total of 992 pregnant women underwent randomization (496 per group) and 898 (90.5%) valid birth weights were available (450 in SPAZ and 448 in SP). LBW incidence was 8.7% (39/450) in SPAZ and 9.4% (42/448) in controls (p-value = 0.79). Compared with controls, pregnant women with SPAZ showed a risk ratio (RR) of 1.16 (95% confidence interval (CI 0.64-2.08]) for preterm births, 0.75 (95% CI 0.17-3.35) for miscarriage and 0.64 (95% CI 0.25-1.64) for stillbirths. No treatment-related serious adverse events (SAEs) have been observed, and there was no significant difference in the number of SAEs (13.5% [67/496] in SPAZ, 16.7% [83/496] in SP, p-value = 0.18) or AEs (17.1% [85/496] in SPAZ, 18.8% [93/496] in SP, p-value = 0.56). CONCLUSION: Adequate prevention regimen with monthly sulfadoxine-pyrimethamine given to all pregnant women has been proved to reduce the risk of LBW in malaria endemic areas. Adding azithromycin to the regimen does not offer further benefits, as far as women receive a malaria prevention regimen early enough during pregnancy. Trial registration Pan African Clinical Trial Registry ( https://pactr.samrc.ac.za/Search.aspx ): PACTR201808177464681. Registered 21 August 2018.

Plasmodium falciparum drug resistance-associated mutations in isolates from children living in endemic areas of Burkina Faso.

BACKGROUND: Artemisinin-based combinations therapy (ACT) is the current frontline curative therapy for uncomplicated malaria in Burkina Faso. Sulfadoxine-pyrimethamine (SP) is used for the preventive treatment of pregnant women (IPTp), while SP plus amodiaquine (SP-AQ) is recommended for children under five in seasonal malaria chemoprevention (SMC). This study aimed to assess the proportions of mutations in the P. falciparum multidrug-resistance 1 (Pfmdr1), P. falciparum chloroquine resistance transporter (Pfcrt), P. falciparum dihydrofolate reductase (pfdhfr), and P. falciparum dihydropteroate synthase (pfdhps), genes from isolates collected during household surveys in Burkina Faso. METHODS: Dried blood spots from Plasmodium falciparum-positive cases at three sites (Orodara, Gaoua, and Banfora) collected during the peak of transmission were analysed for mutations in Pfcrt (codons 72-76, 93, 97, 145, 218, 343, 350 and 353), Pfmdr-1 (codons 86, 184, 1034, 1042 and 1246) dhfr (codons 51, 59, 108, 164) and dhps (at codons 431, 436, 437, 540, 581, 613) genes using deep sequencing of multiplexed Polymerase chaine reaction (PCR) amplicons. RESULTS: Of the 377 samples analysed, 346 (91.7%), 369 (97.9%), 368 (97.6%), and 374 (99.2%) were successfully sequenced for Pfcrt, Pfmdr-1, dhfr, and dhps, respectively. Most of the samples had a Pfcrt wild-type allele (89.3%). The 76T mutation was below 10%. The most frequent Pfmdr-1 mutation was detected at codon 184 (Y > F, 30.9%). The single mutant genotype (NFSND) predominated (66.7%), followed by the wild-type genotype (NYSND, 30.4%). The highest dhfr mutations were observed at codon 59R (69.8%), followed by codons 51I (66.6%) and 108 N (14.7%). The double mutant genotype (ACIRSI) predominated (52.4%). For mutation in the dhps gene, the highest frequency was observed at codon 437 K (89.3%), followed by codons 436 A (61.2%), and 613 S (14.4%). The double mutant genotype (IAKKAA) and the single mutant genotype (ISKKAA) were predominant (37.7% and 37.2%, respectively). The most frequent dhfr/dhps haplotypes were the triple mutant ACIRSI/IAKKAA (23%), the wild-type ACNCSI/ISKKAA (19%) and the double mutant ACIRSI/ISKKAA (14%). A septuple mutant ACIRNI/VAKKGA was observed in 2 isolates from Gaoua (0.5%). CONCLUSION: The efficacy of ACT partner drugs and drugs used in IPTp and SMC does not appear to be affected by the low proportion of highly resistant mutants observed in this study. Continued monitoring, including molecular surveillance, is critical for decision-making on effective treatment policy in Burkina Faso.

Seasonal malaria chemoprevention in a context of high presumed sulfadoxine-pyrimethamine resistance: malaria morbidity and molecular drug resistance profiles in South Sudan.

BACKGROUND: Seasonal malaria chemoprevention (SMC) using sulfadoxine-pyrimethamine plus amodiaquine (SP-AQ), is a community-based malaria preventive strategy commonly used in the Sahel region of sub-Saharan Africa. However, to date it has not been implemented in East Africa due to high SP resistance levels. This paper is a report on the implementation of SMC outside of the Sahel in an environment with a high level of presumed SP-resistance: five cycles of SMC using SPAQ were administered to children 3-59 months during a period of high malaria transmission (July-December 2019) in 21 villages in South Sudan. METHODS: A population-based SMC coverage survey was combined with a longitudinal time series analysis of health facility and community health data measured after each SMC cycle. SMC campaign effectiveness was assessed by Poisson model. SPAQ molecular resistance markers were additionally analysed from dried blood spots from malaria confirmed patients. RESULTS: Incidence of uncomplicated malaria was reduced from 6.6 per 100 to an average of 3.2 per 100 after SMC administration (mean reduction: 53%) and incidence of severe malaria showed a reduction from 21 per 10,000 before SMC campaign to a mean of 3.3 per 10,000 after each cycle (mean reduction: 84%) in the target group when compared to before the SMC campaign. The most prevalent molecular haplotype associated with SP resistance was the IRNGE haplotype (quintuple mutant, with 51I/59R/108N mutation in pfdhfr + 437G/540E in pfdhps). In contrast, there was a low frequency of AQ resistance markers and haplotypes resistant to both drugs combined (< 2%). CONCLUSIONS: The SMC campaign was effective and could be used as an additional preventive tool in seasonal malaria settings outside of the Sahel, especially in areas where access to health care is unstable. Malaria case load reduction was observed despite the high level of resistance to SP.

Women's empowerment and uptake of sulfadoxine-pyrimethamine for intermittent preventive treatment of malaria during pregnancy: results from a cross-sectional baseline survey in the Lake endemic region, Kenya.

BACKGROUND: Malaria in pregnancy remains a major public health problem in endemic areas of the sub-Saharan African (SSA) region. However, there is limited understanding of the association between women's empowerment and the uptake of sulfadoxine-pyrimethamine for intermittent preventive treatment of malaria during pregnancy (IPTp-SP) in Kenya. This study examines the association between women's empowerment indicators (decision-making power, control of assets, education, and employment status) and the uptake of three or more doses of IPTp-SP in the Lake endemic region of Kenya. METHODS: The analysis utilized a dataset from a cross-sectional baseline survey of 3129 women aged 15-49 years in Kisumu and Migori Counties who had a live birth within the last 2 years preceding the study. Data were collected between June to August 2021. A descriptive analysis was conducted to show the distribution of respondents by key background characteristics, and bivariate and multivariate logistic regression to examine statistically significant associations between women's empowerment measures and the uptake of 3+ doses of IPTp-SP. RESULTS: Among the 3129 women surveyed, 1978 (65.7%) received 3+ doses of IPTp-SP during their most recent pregnancy. Controlling for individual characteristics and the number of ANC visits, the odds of taking 3+ doses of IPTp-SP increased among women who had high decision-making autonomy (AOR = 2.33; CI = 1.81-3.01; P < 0.001); and tertiary level of educational attainment (AOR = 1.51; CI = 1.10-2.06). However, the association between control of assets and uptake of IPTp-SP was positive but not statistically significant. CONCLUSION: Women's decision-making autonomy and educational attainment were positively associated with the uptake of IPTp-SP. As a result, maternal health interventions should focus on less empowered women, specifically those with less decision-making autonomy and no/low formal education, as they are less likely to achieve optimal uptake of IPTp-SP during pregnancy.

The Effect of Intermittent Preventive Treatment of Malaria During Pregnancy and Placental Malaria on Infant Risk of Malaria.

BACKGROUND: Intermittent preventive treatment of malaria during pregnancy (IPTp) with dihydroartemisinin-piperaquine (DP) provides greater protection from placental malaria than sulfadoxine-pyrimethamine (SP). Some studies suggest placental malaria alters risk of malaria infection in infants, but few have quantified the effect of IPTp on infant susceptibility to malaria. METHODS: Infants born to women enrolled in a randomized clinical trial comparing IPTp-SP and IPTp-DP in Malawi were followed from birth to 24 months to assess effect of IPTp and placental malaria on time to first malaria episode and Plasmodium falciparum incidence. RESULTS: In total, 192 infants born to mothers randomized to IPTp-SP and 195 randomized to IPTp-DP were enrolled. Infants in IPTp exposure groups did not differ significantly regarding incidence of clinical malaria (incidence rate ratio [IRR], 1.03; 95% confidence interval [CI], .58-1.86) or incidence of infection (IRR, 1.18; 95% CI, .92-1.55). Placental malaria exposure was not associated with incidence of clinical malaria (IRR, 1.03; 95% CI, .66-1.59) or infection (IRR, 1.15; 95% CI, .88-1.50). Infant sex, season of birth, and maternal gravidity did not confound results. CONCLUSIONS: We did not find evidence that IPTp regimen or placental malaria exposure influenced risk of malaria during infancy in this population. Clinical Trials Registration. NCT03009526.

An exploratory study of seasonal malaria chemoprevention and pharmacovigilance for under-five children in Kebbi State, Nigeria.

Background: Seasonal malaria chemoprevention (SMC) is an important public health intervention that is being used to reduce the burden of malaria in sub-Saharan Africa. Objectives: This study aimed to evaluate the implementation of SMC and pharmacovigilance practices in under-five children in Kebbi State, Nigeria. Materials and Methods: The methodology involved a comprehensive review of tools for managing SMC commodities, training data collectors, and fieldwork to evaluate all local government area (LGA) stores, the central medical store (CMS), and selected health facilities based on the sample size determined. Data were collected using SurveyCTO software and analyzed using MS Excel. Twenty-one data reviewers visited the CMS, 21 LGA stores, and 315 health facilities. Results: Our study uncovered significant inaccuracies in documentation, which led to many commodities needing to be more effectively accounted for regarding sources. Data triangulation showed inconsistencies between tools and physical counts that do not match the quantities on inventory control cards. Most primary health-care (PHC) staff in charge of SMC have been formally trained in pharmacovigilance. About 75% (237) of PHCs referred cases of adverse drug reactions (ADRs) to a secondary health-care facility, while 14% (45) treated the symptoms of the ADR with another drug, and 7% (21) took no action, and the reaction resolved on its own. Conclusions: This study provides insight into the challenges and opportunities for improving the implementation of SMC and pharmacovigilance practices in Kebbi State, Nigeria, and has important implications for other settings with similar challenges.

Molecular surveillance for anti-malarial drug resistance and genetic diversity of Plasmodium falciparum after chloroquine and sulfadoxine-pyrimethamine withdrawal in Quibdo, Colombia, 2018.

BACKGROUND: Resistance to anti-malarial drugs is associated with polymorphisms in target genes and surveillance for these molecular markers is important to detect the emergence of mutations associated with drug resistance and signal recovering sensitivity to anti-malarials previously used. METHODS: The presence of polymorphisms in genes associated with Plasmodium falciparum resistance to chloroquine and sulfadoxine-pyrimethamine was evaluated by Sanger sequencing, in 85 P. falciparum day of enrollment samples from a therapeutic efficacy study of artemether-lumefantrine conducted in 2018-2019 in Quibdo, Colombia. Samples were genotyped to assess mutations in pfcrt (codons 72-76), pfdhfr (codons 51, 59, 108, and 164), and pfdhps genes (codons 436, 437, 540, and 581). Further, the genetic diversity of infections using seven neutral microsatellites (NMSs) (C2M34, C3M69, Poly α, TA1, TA109, 2490, and PfPK2) was assessed. RESULTS: All isolates carried mutant alleles for pfcrt (K76T and N75E), and for pfdhfr (N51I and S108N), while for pfdhps, mutations were observed only for codon A437G (32/73, 43.8%). Fifty samples (58.8%) showed a complete neutral microsatellites (NMS) profile. The low mean number of alleles (2 ± 0.57) per locus and mean expected heterozygosity (0.17 ± 0.03) showed a reduced genetic diversity. NMS multilocus genotypes (MMG) were built and nine MMG were identified. CONCLUSIONS: Overall, these findings confirm the fixation of chloroquine and pyrimethamine-resistant alleles already described in the literature, implying that these drugs are not currently appropriate for use in Colombia. In contrast, mutations in the pfdhps gene were only observed at codon 437, an indication that full resistance to sulfadoxine has not been achieved in Choco. MMGs found matched the clonal lineage E variant 1 previously reported in northwestern Colombia.

A cluster randomized trial of delivery of intermittent preventive treatment of malaria in pregnancy at the community level in Malawi.

BACKGROUND: Malaria in pregnancy doubles the risk of low birthweight; up to 11% of all neonatal deaths in sub-Saharan Africa are associated with malaria in pregnancy. To prevent these and other adverse health consequences, the World Health Organization recommends administering intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine for all pregnant women at each antenatal care (ANC) visit, starting as early as possible in the second trimester. The target is for countries to administer a minimum of three doses (IPTp3+) to at least 85% of pregnant women. METHODS: A cluster randomized, controlled trial was conducted to assess the effect of delivery of IPTp by community health workers on the coverage of IPTp3 + and ANC visits in Malawi. Community delivery of IPTp was implemented within two districts in Malawi over a 21-month period, from November 2018 to July 2020. In control sites, IPTp was delivered at health facilities. Representative samples of women who delivered in the prior 12 months were surveyed at baseline (n = 370, December 2017) and endline (n = 687, August 2020). A difference in differences analysis was conducted to assess the change in coverage of IPTp and ANC over time, accounting for clustering at the health facility level. RESULTS: Overall IPTp coverage increased over the study period. At baseline, women received a mean of 2.3 IPTp doses (range 0-5 doses) across both arms, and at endline, women received a mean of 2.8 doses (range 0-9 doses). Despite overall increases, the change in IPTp3 + coverage was not significantly different between intervention and control groups (6.9%, 95% CI: -5.9%, 19.6%). ANC4 + coverage increased significantly in the intervention group compared with the control group, with a difference-in-differences of 25.3% points (95% CI: 1.3%, 49.3%). CONCLUSIONS: In order to reduce the burden of malaria in pregnancy, new strategies are needed to improve uptake of effective interventions such as IPTp. While community health workers' delivery of IPTp did not increase uptake in this study, they may be effective in other settings or circumstances. Further research can help identify the health systems characteristics that are conducive to community delivery of IPTp and the operational requirements for effective implementation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03376217. Registered December 6, 2017, https://clinicaltrials.gov/ct2/show/NCT03376217 .

A qualitative assessment of the health systems factors influencing the prevention of malaria in pregnancy using intermittent preventive treatment and insecticide-treated nets in Ghana.

BACKGROUND: Ghana has adopted and implemented intermittent preventive treatment using sulfadoxine-pyrimethamine (IPTp-SP) and insecticide-treated nets (ITNs) in an antenatal care (ANC) context to prevent malaria among pregnant women. However, the increased ANC attendance and its frequency facilitated by a free maternal health care policy in Ghana does not correspond with the uptake of IPTp-SP and ITN use among pregnant women. This study sought to elucidate the contextual health system factors influencing the delivery of IPTp-SP and ITN from a related quantitative study conducted in Ghana. METHODS: This is the qualitative section of a mixed-methods study design, where audio recorded key informant interviews (KIIs) were conducted with health workers from across health facilities, districts, regional and national health directorates. The KIIs elicited information on health worker knowledge, perceptions, and rationale for the delivery practices of IPTp-SP and ITN revealed in the quantitative findings. The interviews were transcribed and imported into NVivo for analysis. Using the World Health Organization (WHO) Health Systems Framework as the theoretical basis, thematic analysis was conducted under broad themes of the building blocks. Findings are presented in narrative quotes, with a mindmap used to summarize the various health system factors and their interrelated relationship influencing the delivery of IPTp-SP and ITN. RESULTS: Health system factors identified included health staff untrained on malaria delivery directives due to an ineffective trainer of trainer (ToT) system. Additionally, health worker confusion on when to commence SP (at quickening or ≥ 16 weeks) was found to result in delayed start of SP. Stock-outs in facilities due to procurement delays at the national level resulted in missed opportunities to deliver SP to eligible pregnant women at the ANC. Similarly, ITN stock outs led to eligible pregnant women not receiving one at ANC clinics. CONCLUSION: Poor health worker knowledge on policy directives, a consequence of ineffective training strategy led to delayed delivery of IPTp-SP to eligible pregnant women. Supply chain management challenges related to stock of SP and ITN resulted in missed opportunities to deliver the interventions to pregnant women attending ANC.

Effect of three years' seasonal malaria chemoprevention on molecular markers of resistance of Plasmodium falciparum to sulfadoxine-pyrimethamine and amodiaquine in Ouelessebougou, Mali.

BACKGROUND: In 2012, seasonal malaria chemoprevention (SMC) was recommended as policy for malaria control by the World Health Organization (WHO) in areas of highly seasonal malaria transmission across the Sahel sub-region in Africa along with monitoring of drug resistance. We assessed the long-term impact of SMC on Plasmodium falciparum resistance to sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) over a 3-year period of SMC implementation in the health district of Ouelessebougou, Mali. METHODS: In 8 randomly selected sub-districts of Ouelessebougou, Mali, children aged 0-5 years were randomly selected during cross-sectional surveys at baseline (August 2014) and 1, 2 and 3 years post-SMC, at the beginning and end of the malaria transmission season. Blood smears and blood spots on filter paper were obtained and frequencies of mutation in P. falciparum genes related to resistance to SP and AQ (Pfdhfr, Pfdhps, Pfmdr1, and Pfcrt) were assessed by PCR amplification on individual samples and PCR amplification followed by deep sequencing on pooled (by site and year) samples. RESULTS: At each survey, approximately 50-100 individual samples were analysed by PCR amplification and a total of 1,164 samples were analysed by deep sequencing with an average read depth of 18,018-36,918 after pooling by site and year. Most molecular markers of resistance did not increase in frequency over the period of study (2014-2016). After 3 years of SMC, the frequencies of Pfdhps 540E, Pfdhps 437G and Pfcrt K76T remained similar compared to baseline (4.0 vs 1.4%, p = 0.41; 74.5 vs 64.6%, p = 0.22; 71.3 vs 67.4%, p = 0.69). Nearly all samples tested carried Pfdhfr 59R, and this proportion remained similar 3 years after SMC implementation (98.8 vs 100%, p = 1). The frequency of Pfmdr1 N86Y increased significantly over time from 5.6% at baseline to 18.6% after 3 years of SMC (p = 0.016). Results of pooled analysis using deep sequencing were consistent with those by individual analysis with standard PCR, but also indicated for the first time the presence of mutations at the Pfdhps A581G allele at a frequency of 11.7% after 2 years of SMC, as well as the Pfdhps I431V allele at frequencies of 1.6-9.3% following 1 and 2 years of SMC, respectively. CONCLUSION: Two and 3 years of SMC implementation were associated with increased frequency of the Pfmdr1 N86Y mutation but not Pfdhps 540E, Pfdhps 437G and Pfcrt K76T. The first-time detection of the Pfdhps haplotype bearing the I431V and A581G mutations in Mali, even at low frequency, warrants further long-term surveillance.

Risk factors for placental malaria, sulfadoxine-pyrimethamine doses, and birth outcomes in a rural to urban prospective cohort study on the Bandiagara Escarpment and Bamako, Mali.

BACKGROUND: Malaria in Mali remains a primary cause of morbidity and mortality, with women at high risk during pregnancy for placental malaria (PM). Risk for PM and its association with birth outcomes was evaluated in a rural to urban longitudinal cohort on the Bandiagara Escarpment and the District of Bamako. METHODS: Placental samples (N = 317) were collected from 249 mothers who were participants in a prospective cohort study directed by BIS in the years 2011 to 2019. A placental pathologist and research assistant evaluated the samples by histology in blinded fashion to assess PM infection stage and parasite density. Generalized estimating equations (GEE) were used to model the odds of PM infection. RESULTS: In a multivariable model, pregnancies in Bamako, beyond secondary education, births in the rainy season (instead of the hot dry season), and births to women who had ≥ 3 doses of sulfadoxine-pyrimethamine (SP) instead of no doses were associated with reduced odds of experiencing PM (active and past infections combined). Births in later years of the study were strongly associated with reduced odds of PM. Maternal age, which was positively associated with offspring year of birth, was significant as a predictor of PM only if offspring year of birth was omitted from the model. Gravidity was positively associated with both maternal age and offspring year of birth such that if either variable was included in the model, then gravidity was no longer significant. However, if maternal age or year of offspring birth were not adjusted for, then the odds of PM were nearly two-fold higher in primigravida compared to multigravida. Birth outcomes improved (+ 285 g birth weight, + 2 cm birth length, + 75 g placental weight) for women who had ≥ 3 doses of SP compared to no doses, but no difference was detected in birth weight or length for women who had 2 instead of ≥ 3 SP doses. However, at 2 instead of ≥ 3 doses placentas were 36 g lighter and the odds of low birth weight (< 2500 g) were 14% higher. Severe parasite densities (> 10% erythrocytes infected) were significantly associated with decreases in birth weight, birth length, and placental weight, as were chronic PM infections. The women who received no SP during pregnancy (7% of the study total) were younger and lacked primary school education. The women who received ≥ 3 doses of SP came from more affluent families. CONCLUSIONS: Women who received no doses of SP during pregnancy experienced the most disadvantageous birth outcomes in both Bamako and on the Bandiagara Escarpment. Such women tended to be younger and to have had no primary school education. Targeting such women for antenatal care, which is the setting in which SP is most commonly administered in Mali, will have a more positive impact on public health than focusing on the increment from two to three doses of SP, although that increment is also desirable.

Impact of antimalarial resistance and COVID-19 pandemic on malaria care among pregnant women in Northern Uganda (ERASE): protocol of a prospective observational study.

BACKGROUND: Uganda accounts for 5% of all malaria cases and deaths reported globally and, in endemic countries, pregnancy is a risk factor for both acquisition of P. falciparum infection and development of severe malaria. In recent years, malaria control has been threatened by COVID-19 pandemic and by the emergence, in Northern Uganda, of both resistance to artemisinin derivatives and to sulfadoxine-pyrimethamine. METHODS: In this facility-based, prospective, observational study, pregnant women will be recruited at antenatal-care visits and followed-up until delivery. Collected data will explore the incidence of asymptomatic parasitemia and malaria-related outcomes, as well as the attitudes towards malaria prevention, administration of intermittent preventive treatment, healthcare seeking behavior and use of insecticide-treated nets. A subpopulation of women diagnosed with malaria will be recruited and their blood samples will be analyzed for detection of genetic markers of resistance to artemisinin derivatives and sulfadoxine-pyrimethamine. Also, to investigate the impact of COVID-19 on malaria care among pregnant women, a retrospective, interrupted-time series will be conducted on at the study sites for the period January 2018 to December 2021. DISCUSSION: The present study will explore the impact of COVID-19 pandemic on incidence of malaria and malaria-related adverse outcomes, along with the prevalence of resistance to artemisinin derivatives and to sulfadoxine-pyrimethamine. To our knowledge, this is the first study aiming to explore the combined effect of these factors on a cohort of pregnant women. TRIAL REGISTRATION: This study has been registered on the ClinicalTrials.gov public website on 26th April, 2022. CLINICALTRIALS: gov Identifier: NCT05348746.

Impact of mobile phone intervention on intermittent preventive treatment of malaria during pregnancy in Burkina Faso : A pragmatic randomized trial.

PURPOSE: Intermittent preventive treatment of malaria with sulphadoxine-pyrimethamine for pregnant women (IPTp-SP) coverage remains far below the desirable goal of at least three doses before delivery. This study evaluates an innovative intervention using mobile phones as a means of increasing coverage for the third dose of IPTp-SP. METHODS: This study in Burkina Faso was designed as an open-label, pragmatic, two-arm, randomised trial. Pregnant women who attended antenatal clinic (ANC) visits were included at their first ANC visit and followed until delivery. The intervention was built around the use of mobile phones as means ensuring direct tracking of pregnant women. RESULTS: Two hundred and forty-eight (248) pregnant women were included in the study. The proportion of women who received at least three doses of IPTp-SP was 54.6 %. In the intervention group, 54.1 % of women received at least three doses of IPTp-SP versus 55.1 % in the control group, a non-significant difference (adjusted odds ratio "aOR", 0.86 ; 95 % confidence interval "95 % CI", 0.49-1.51). Women in the intervention group were more likely to carry out their ANC visits in a timely manner than those in the control group (aOR, 3.21 ; 95 % CI, 1.91-5.39). CONCLUSION: While mobile phone intervention did not increase the proportion of women receiving three doses of IPTp-SP, it did help to increase the proportion of timely ANC visits. TRIAL REGISTRATION: PACTR202106905150440.

Global Analysis of Plasmodium falciparum Dihydropteroate Synthase Variants Associated with Sulfadoxine Resistance Reveals Variant Distribution and Mechanisms of Resistance: A Computational-Based Study.

The continual rise in sulfadoxine (SDX) resistance affects the therapeutic efficacy of sulfadoxine-pyrimethamine; therefore, careful monitoring will help guide its prolonged usage. Mutations in Plasmodium falciparum dihydropteroate synthase (Pfdhps) are being surveilled, based on their link with SDX resistance. However, there is a lack of continuous analyses and data on the potential effect of molecular markers on the Pfdhps structure and function. This study explored single-nucleotide polymorphisms (SNPs) in Pfdhps that were isolated in Africa and other countries, highlighting the regional distribution and its link with structure. In total, 6336 genomic sequences from 13 countries were subjected to SNPs, haplotypes, and structure-based analyses. The SNP analysis revealed that the key SDX resistance marker, A437G, was nearing fixation in all countries, peaking in Malawi. The mutation A613S was rare except in isolates from the Democratic Republic of Congo and Malawi. Molecular docking revealed a general loss of interactions when comparing mutant proteins to the wild-type protein. During MD simulations, SDX was released from the active site in mutants A581G and A613S before the end of run-time, whereas an unstable binding of SDX to mutant A613S and haplotype A437A/A581G/A613S was observed. Conformational changes in mutant A581G and the haplotypes A581G/A613S, A437G/A581G, and A437G/A581G/A613S were seen. The radius of gyration revealed an unfolding behavior for the A613S, K540E/A581G, and A437G/A581G systems. Overall, tracking such mutations by the continuous analysis of Pfdhps SNPs is encouraged. SNPs on the Pfdhps structure may cause protein-drug function loss, which could affect the applicability of SDX in preventing malaria in pregnant women and children.