Intermittent screening and treatment or intermittent preventive treatment with dihydroartemisinin-piperaquine versus intermittent preventive treatment with sulfadoxine-pyrimethamine for the control of malaria during pregnancy in western Kenya: an open-label, three-group, randomised controlled superiority trial

Delivery effectiveness of and adherence to intermittent preventive treatment for malaria in pregnancy with dihydroartemisinin-piperaquine with or without targeted information transfer or sulfadoxine-pyrimethamine in western Kenya: a three-armed, pragmatic, open-label, cluster-randomised trial

BACKGROUND

High-level resistance to sulfadoxine-pyrimethamine threatens the efficacy of WHO-recommended intermittent preventive treatment in pregnancy (IPTp) with single-dose sulfadoxine-pyrimethamine to prevent malaria. Monthly IPTp with dihydroartemisinin-piperaquine, a 3-day regimen, is an emerging alternative, but this regimen poses potential implementation and adherence challenges. We aimed to assess adherence to a multiday IPTp with dihydroartemisinin-piperaquine regimen and its delivery effectiveness in routine antenatal care settings in western Kenya.

METHODS

We conducted a pragmatic, three-armed, open-label, cluster-randomised trial in antenatal clinics in 18 health-care facilities (six facilities per group) in Kisumu County and Homa Bay County in western Kenya. Clusters were facilities offering routine antenatal care services provided by trained Ministry of Health staff with 100 or more antenatal clinic attendances per month between July, 2018, and June, 2019. Private or mission hospitals, dispensaries, referral hospitals, and trial sites were excluded. Individuals in their first trimester, living with HIV, or who were not attending a scheduled antenatal clinic visit were excluded. The 18 antenatal clinics were grouped into matched triplets stratified by location and clinics in each matched triplet were randomly assigned to one of the three study groups (1:1:1). Masking was not possible. Two groups were given IPTp with dihydroartemisinin-piperaquine (one group with a targeted information transfer intervention and one group without any additional interventions) and one group was given the standard of care (ie, IPTp with sulfadoxine-pyrimethamine). The primary endpoint, adherence, was defined as the proportion of participants completing their most recent 3-day IPTp with dihydroartemisinin-piperaquine regimen. This completion was verified by pill counts during home visits no more than 2 days after participants' 3-day regimens ended. The secondary endpoint, delivery effectiveness, was defined as the proportion of participants who received the correct number of IPTp tablets and correctly repeated dosing instructions (ie, correctly recalled the instructions they received about self-administered dihydroartemisinin-piperaquine doses and the number of sulfadoxine-pyrimethamine tablets they had received) at their exit from the antenatal clinic. Individuals receiving treatment for malaria, visiting a clinic for registration only, or interviewed during IPTp drug stock-outs were excluded from analyses. We used generalised linear mixed models to compare endpoints among the IPTp with dihydroartemisinin-piperaquine groups. This trial was registered with ClinicalTrials.gov, NCT04160026, and is complete.

FINDINGS

15 facilities (five per group) completed the trial, with 1189 participants having exit interviews (377 in the IPTp with sulfadoxine-pyrimethamine group, 408 in the IPTp with dihydroartemisinin-piperaquine only group, and 404 in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group) and 586 participants having home visits (267 in the IPTp with dihydroartemisinin-piperaquine only group and 319 in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group) from Sept 8 to Dec 10, 2020. Relative to the IPTp with dihydroartemisinin-piperaquine only group, adherence was 16% higher in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group (266 [83%] of 319 participants vs 196 [73%] of 267 participants; adjusted relative risk [RR] 1·16, 95% CI 1·03-1·31; p=0·0140). Delivery effectiveness in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group was not significantly different from that in the IPTp with sulfadoxine-pyrimethamine group (352 [87%] of 403 participants vs 335 [89%] of 375 participants; adjusted RR 0·97, 95% CI 0·90-1·05; p=0·4810). However, delivery effectiveness in the IPTp with dihydroartemisinin-piperaquine only group was significantly lower than in the IPTp with sulfadoxine-pyrimethamine group (300 [74%] of 404 participants vs 335 [89%] of 375 participants; 0·84, 0·75-0·95; p=0·0030).

INTERPRETATION

Targeted information transfer interventions to health-care providers and pregnant individuals boost antenatal care delivery adherence to a multiday regimen with dihydroartemisinin-piperaquine.

FUNDING

European and Developing Countries Clinical Trials Partnership 2, UK Joint Global Health Trials Scheme of the Foreign, Commonwealth and Development Office, Medical Research Council, National Institute for Health and Care Research, and Wellcome Trust; and Swedish International Development Cooperation Agency.

Intermittent preventive treatment regimens for malaria in HIV-positive pregnant women

BACKGROUND

Malaria and HIV infection overlap geographically in sub-Saharan Africa and share risk factors. HIV infection increases malaria's severity, especially in pregnant women. The World Health Organization (WHO) recommends intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) for pregnant women living in areas of stable malaria transmission. However, HIV-positive women on daily cotrimoxazole prophylaxis (recommended for prevention of opportunistic infections in people with HIV) cannot receive SP due to adverse drug interactions, so malaria prevention in this vulnerable population currently relies on daily cotrimoxazole prophylaxis alone. This review is based on a new protocol and provides an update to the 2011 Cochrane Review that evaluated alternative drugs for IPTp to prevent malaria in HIV-positive women.

OBJECTIVES

To compare the safety and efficacy of intermittent preventive treatment regimens for malaria prevention in HIV-positive pregnant women.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, three other databases, and two trial registries to 31 January 2024. To identify relevant additional studies or unpublished work, we checked references and contacted study authors and other researchers working on malaria and HIV.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing any intermittent preventive treatment regimen for preventing malaria in HIV-positive pregnant women against daily cotrimoxazole prophylaxis alone, placebo, current or previous standard of care, or combinations of these options. By 'standard of care' we refer to the country's recommended drug regimen to prevent malaria in pregnancy among HIV-positive women, or the treatment that a trial's research team considered to be the standard of care.

DATA COLLECTION AND ANALYSIS

Review authors, in pairs, independently screened all records identified by the search strategy, applied inclusion criteria, assessed risk of bias in included trials, and extracted data. We contacted trial authors when additional information was required. We presented dichotomous outcomes using risk ratios (RRs), count outcomes as incidence rate ratios (IRRs), and continuous outcomes as mean differences (MDs). We presented all measures of effect with 95% confidence intervals (CIs). We assessed the certainty of the evidence using the GRADE approach for what we considered to be the main comparisons and outcomes.

MAIN RESULTS

We included 14 RCTs, with a total of 4976 HIV-positive pregnant women initially randomized. All trials assessed the efficacy and safety of one antimalarial used as IPTp (mefloquine, dihydroartemisinin/piperaquine, SP, or azithromycin) with or without daily cotrimoxazole, compared to daily cotrimoxazole alone, placebo, or a standard of care regimen. We grouped the trials into nine comparisons. Our main comparison evaluated the current standard of care (daily cotrimoxazole) with another drug regimen (mefloquine or dihydroartemisinin/piperaquine) versus daily cotrimoxazole with or without placebo. In this comparison, two trials evaluated mefloquine and three evaluated dihydroartemisinin/piperaquine. We conducted meta-analyses that included trials evaluating dihydroartemisinin/piperaquine plus cotrimoxazole, and trials that evaluated mefloquine plus cotrimoxazole, as we considered there to be no qualitative or quantitative heterogeneity among trials for most outcomes. We considered drug-related adverse events and HIV-related outcomes to be drug-specific. Daily cotrimoxazole prophylaxis plus another drug regimen (mefloquine or dihydroartemisinin/piperaquine) probably results in lower risk of maternal peripheral parasitaemia at delivery (RR 0.62, 95% CI 0.41 to 0.95; 2406 participants, 5 trials; moderate-certainty evidence). It results in little or no difference in maternal anaemia cases at delivery (RR 0.98, 95% CI 0.90 to 1.07; 2417 participants, 3 trials; high-certainty evidence). It probably results in a decrease in placental malaria measured by blood smear (RR 0.54, 95% CI 0.31 to 0.93; 1337 participants, 3 trials; moderate-certainty evidence), and probably results in little or no difference in low birth weight (RR 1.16, 95% CI 0.95 to 1.41; 2915 participants, 5 trials; moderate-certainty evidence). There is insufficient evidence to ascertain whether daily cotrimoxazole prophylaxis plus another drug regimen affects the risk of cord blood parasitaemia (RR 0.27, 95% CI 0.04 to 1.64; 2696 participants, 5 trials; very low-certainty evidence). Daily cotrimoxazole prophylaxis plus another drug regimen probably results in little or no difference in foetal loss (RR 1.03, 95% CI 0.73 to 1.46; 2957 participants, 5 trials; moderate-certainty evidence), and may result in little or no difference in neonatal mortality (RR 1.21, 95% CI 0.68 to 2.14; 2706 participants, 4 trials; low-certainty evidence). Due to the probability of an increased risk of mother-to-child HIV transmission and some adverse drug effects noted with mefloquine, we also looked at the results for dihydroartemisinin/piperaquine specifically. Dihydroartemisinin/piperaquine plus daily contrimoxazole probably results in little to no difference in maternal peripheral parasitaemia (RR 0.59, 95% CI 0.31 to 1.11; 1517 participants, 3 trials; moderate-certainty evidence) or anaemia at delivery (RR 0.95, 95% CI 0.82 to 1.10; 1454 participants, 2 trials; moderate-certainty evidence), but leads to fewer women having placental malaria when measured by histopathologic analysis (RR 0.67, 95% CI 0.50 to 0.90; 1570 participants, 3 trials; high-certainty evidence). The addition of dihydroartemisinin/piperaquine to daily cotrimoxazole probably made little to no difference to rates of low birth weight (RR 1.13, 95% CI 0.87 to 1.48; 1695 participants, 3 trials), foetal loss (RR 1.14, 95% CI 0.68 to 1.90; 1610 participants, 3 trials), or neonatal mortality (RR 1.03, 95% CI 0.39 to 2.72; 1467 participants, 2 trials) (all moderate-certainty evidence). We found low-certainty evidence of no increased risk of gastrointestinal drug-related adverse events (RR 1.42, 95% CI 0.51 to 3.98; 1447 participants, 2 trials) or mother-to-child HIV transmission (RR 1.54, 95% CI 0.26 to 9.19; 1063 participants, 2 trials).

AUTHORS' CONCLUSIONS

Dihydroartemisinin/piperaquine and mefloquine added to daily cotrimoxazole seem to be efficacious in preventing malaria infection in HIV-positive pregnant women compared to daily cotrimoxazole alone. However, increased risk of HIV transmission to the foetus and poor drug tolerability may be barriers to implementation of mefloquine in practice. In contrast, the evidence suggests that dihydroartemisinin/piperaquine does not increase the risk of HIV mother-to-child transmission and is well tolerated.

Uptake and Effectiveness of Intermittent Preventive Treatment with Sulfadoxine-Pyrimethamine during Pregnancy in Africa: A Scoping Review

Malaria poses a significant threat to pregnant women in sub-Saharan Africa, necessitating effective interventions like the intermittent preventive treatment of malaria in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP). However, challenges persist in the uptake and effectiveness of this intervention. This scoping review aims to explore IPTp-SP uptake in African countries, identify influencing factors, and assess its effectiveness in preventing malaria and adverse outcomes in pregnancy. This scoping review follows Arksey and O'Malley's framework, employing the PRISMA-ScR guidelines for reporting. Searches were conducted in PubMed, Embase, Scopus, JSTOR, Web of Science, Google Scholar, and ProQuest, focusing on studies post-2000 published in the English language. The search produced 15,153 records, of which 104 full-text records were eligible and 101 papers were included in this review. The findings suggest varying IPTp-SP uptake rates, spanning from 5.3% to 98.9%, with their effectiveness supported by longitudinal studies, randomised controlled-trials (RCTs), cross-sectional surveys, and mixed-method studies. IPTp-SP demonstrates efficacy in reducing malaria during pregnancy, placental parasitaemia, and anaemia episodes, alongside improved birth outcomes. Common adverse effects of IPTp-SP include prematurity and low birth weight. Facilitators of IPTp-SP uptake include education and ANC attendance, while commonly reported barriers included inadequate knowledge and healthcare system challenges. The findings also suggest adverse effects such as prematurity, low birth weight, and maternal and perinatal mortality associated with IPTp-SP uptake. It is vital to strengthen antenatal care services by integrating comprehensive counselling on IPTp-SP and address healthcare system challenges. Community engagement, women's empowerment, and context-specific interventions are necessary for promoting IPTp-SP uptake and improving maternal and neonatal health outcomes in Africa.

Pharmacokinetics of piperaquine and its association with intermittent malaria preventive therapy outcomes during pregnancy

BACKGROUND

Dihydroartemisinin-piperaquine (DHP) recently showed superior effectiveness over sulfadoxine-pyrimethamine for malaria intermittent preventive treatment in pregnancy (IPTp). We investigated day 7 piperaquine pharmacokinetics and its therapeutic efficacy in preventing malaria during pregnancy.

METHODS

Malaria-free (mRDT) pregnant women (n = 400) who received monthly IPTp-DHP were enrolled and followed till delivery. Day 7 Plasma piperaquine concentrations were determined after each IPTp dose using UPLC/MS/MS. IPTp outcomes (symptomatic malaria and parasitemia during pregnancy, placental malaria, and maternal malaria at delivery) were monitored. Linear mixed model and Cox regression were used to assess predictors of day 7 piperaquine concentration and treatment outcome, respectively.

RESULTS

The incidences of symptomatic malaria and parasitemia during pregnancy per 100 person-year at risk were 2 and 33, respectively. The prevalence of histopathologically confirmed placental malaria and maternal malaria at delivery were 3% and 9.8%, respectively. Repeated monthly IPTp-DHP resulted in significantly increased day 7 plasma piperaquine concentration (p < 0.001). Following the 1st, 2nd, and 3rd monthly IPTp-DHP doses, the proportions of women with day 7 piperaquine concentration below the therapeutic threshold (< 30 ng/mL) were 6.1%, 4.1% and 3.6%, respectively. Factors such as maternal age, body weight and trimester were not significant predictors of day 7 piperaquine concentration. However, having a low day 7 piperaquine plasma concentration (< 30 ng/mL) was significantly associated with a higher risk of parasitemia during pregnancy (p = 0.004).

CONCLUSION

Lower day 7 piperaquine plasma concentration is a risk factor for parasitemia during pregnancy. Single plasma sampling at day 7 can be used to monitor piperaquine effectiveness during IPTp-DHP.

TRIAL REGISTRATION

Registered 09/12/2016, PACTR201612001901313.

Pathways through which intermittent preventive treatment for malaria in pregnancy influences child growth faltering: a mediation analysis

Background

Intermittent preventive treatment for malaria in pregnancy (IPTp) can improve birth outcomes, but whether it confers benefits to postnatal growth is unclear. We investigated the effect of IPTp on infant growth in Uganda and its pathways of effects using causal mediation analyses.

Methods

We analyzed data from 633 infants born to mothers enrolled in a randomized trial of monthly IPTp with dihydroartemisinin-piperaquine (DP) vs sulfadoxine-pyrimethamine (SP) (NCT02793622). Weight and length were measured from 0-12 months of age. Using generalized linear models, we estimated effects of DP vs. SP on gravidity-stratified mean length-for-age (LAZ) and weight-for-length Z-scores (WLZ). We investigated mediation by placental malaria, gestational weight change, maternal anemia, maternal inflammation-related proteins, preterm birth, birth length, and birth weight. Mediation models adjusted for infant sex, gravidity, gestational age at enrollment, maternal age, maternal parasitemia at enrollment, education, and wealth.

Findings

SP increased LAZ by 0.18-0.28 Z from birth through age 4 months compared to DP, while DP increased WLZ by 0.11-0.28 Z from 2-8 months compared to SP among infants of multigravidae. We did not observe these differences among primigravida. Mediators of SP included increased birth weight and length and maternal stem cell factor at delivery. Mediators of DP included placental malaria and birth length, maternal IL-18, CDCP1, and CD6 at delivery.

Interpretation

In high malaria transmission settings, different IPTp regimens influenced infant growth among multigravidae through distinct pathways in the period of exclusive breastfeeding, when few other interventions are available.

Funding

Stanford Center for Innovation and Global Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bill & Melinda Gates Foundation.

Monthly Sulfadoxine-Pyrimethamine During Pregnancy Prevents Febrile Respiratory Illnesses: A Secondary Analysis of a Malaria Chemoprevention Trial in Uganda

Background

Trials evaluating antimalarials for intermittent preventive treatment in pregnancy (IPTp) have shown that dihydroartemisinin-piperaquine (DP) is a more efficacious antimalarial than sulfadoxine-pyrimethamine (SP); however, SP is associated with higher birthweight, suggesting that SP demonstrates "nonmalarial" effects. Chemoprevention of nonmalarial febrile illnesses (NMFIs) was explored as a possible mechanism.

Methods

In this secondary analysis, we leveraged data from 654 pregnant Ugandan women without HIV infection who participated in a randomized controlled trial comparing monthly IPTp-SP with IPTp-DP. Women were enrolled between 12 and 20 gestational weeks and followed through delivery. NMFIs were measured by active and passive surveillance and defined by the absence of malaria parasitemia. We quantified associations among IPTp regimens, incident NMFIs, antibiotic prescriptions, and birthweight.

Results

Mean "birthweight for gestational age" Z scores were 0.189 points (95% CI, .045-.333) higher in women randomized to IPTp-SP vs IPTp-DP. Women randomized to IPTp-SP had fewer incident NMFIs (incidence rate ratio, 0.74; 95% CI, .58-.95), mainly respiratory NMFIs (incidence rate ratio, 0.69; 95% CI, .48-1.00), vs IPTp-DP. Counterintuitively, respiratory NMFI incidence was positively correlated with birthweight in multigravidae. In total 75% of respiratory NMFIs were treated with antibiotics. Although overall antibiotic prescriptions were similar between arms, for each antibiotic prescribed, "birthweight for gestational age" Z scores increased by 0.038 points (95% CI, .001-.074).

Conclusions

Monthly IPTp-SP was associated with reduced respiratory NMFI incidence, revealing a potential nonmalarial mechanism of SP and supporting current World Health Organization recommendations for IPTp-SP, even in areas with high-grade SP resistance. While maternal respiratory NMFIs are known risk factors of lower birthweight, most women in our study were presumptively treated with antibiotics, masking the potential benefit of SP on birthweight mediated through preventing respiratory NMFIs.

Chemoprevention for malaria with monthly intermittent preventive treatment with dihydroartemisinin-piperaquine in pregnant women living with HIV on daily co-trimoxazole in Kenya and Malawi: a randomised, double-blind, placebo-controlled trial

BACKGROUND

The efficacy of daily co-trimoxazole, an antifolate used for malaria chemoprevention in pregnant women living with HIV, is threatened by cross-resistance of Plasmodium falciparum to the antifolate sulfadoxine-pyrimethamine. We assessed whether addition of monthly dihydroartemisinin-piperaquine to daily co-trimoxazole is more effective at preventing malaria infection than monthly placebo plus daily co-trimoxazole in pregnant women living with HIV.

METHODS

We did an individually randomised, two-arm, placebo-controlled trial in areas with high-grade sulfadoxine-pyrimethamine resistance in Kenya and Malawi. Pregnant women living with HIV on dolutegravir-based combination antiretroviral therapy (cART) who had singleton pregnancies between 16 weeks' and 28 weeks' gestation were randomly assigned (1:1) by computer-generated block randomisation, stratified by site and HIV status (known positive vs newly diagnosed), to daily co-trimoxazole plus monthly dihydroartemisinin-piperaquine (three tablets of 40 mg dihydroartemisinin and 320 mg piperaquine given daily for 3 days) or daily co-trimoxazole plus monthly placebo. Daily co-trimoxazole consisted of one tablet of 160 mg sulfamethoxazole and 800 mg trimethoprim. The primary endpoint was the incidence of Plasmodium infection detected in the peripheral (maternal) or placental (maternal) blood or tissue by PCR, microscopy, rapid diagnostic test, or placental histology (active infection) from 2 weeks after the first dose of dihydroartemisinin-piperaquine or placebo to delivery. Log-binomial regression was used for binary outcomes, and Poisson regression for count outcomes. The primary analysis was by modified intention to treat, consisting of all randomised eligible participants with primary endpoint data. The safety analysis included all women who received at least one dose of study drug. All investigators, laboratory staff, data analysts, and participants were masked to treatment assignment. This trial is registered with ClinicalTrials.gov, NCT04158713.

FINDINGS

From Nov 11, 2019, to Aug 3, 2021, 904 women were enrolled and randomly assigned to co-trimoxazole plus dihydroartemisinin-piperaquine (n=448) or co-trimoxazole plus placebo (n=456), of whom 895 (99%) contributed to the primary analysis (co-trimoxazole plus dihydroartemisinin-piperaquine, n=443; co-trimoxazole plus placebo, n=452). The cumulative risk of any malaria infection during pregnancy or delivery was lower in the co-trimoxazole plus dihydroartemisinin-piperaquine group than in the co-trimoxazole plus placebo group (31 [7%] of 443 women vs 70 [15%] of 452 women, risk ratio 0·45, 95% CI 0·30-0·67; p=0·0001). The incidence of any malaria infection during pregnancy or delivery was 25·4 per 100 person-years in the co-trimoxazole plus dihydroartemisinin-piperaquine group versus 77·3 per 100 person-years in the co-trimoxazole plus placebo group (incidence rate ratio 0·32, 95% CI 0·22-0·47, p<0·0001). The number needed to treat to avert one malaria infection per pregnancy was 7 (95% CI 5-10). The incidence of serious adverse events was similar between groups in mothers (17·7 per 100 person-years in the co-trimoxazole plus dihydroartemisinin-piperaquine group [23 events] vs 17·8 per 100 person-years in the co-trimoxazole group [25 events]) and infants (45·4 per 100 person-years [23 events] vs 40·2 per 100 person-years [21 events]). Nausea within the first 4 days after the start of treatment was reported by 29 (7%) of 446 women in the co-trimoxazole plus dihydroartemisinin-piperaquine group versus 12 (3%) of 445 women in the co-trimoxazole plus placebo group. The risk of adverse pregnancy outcomes did not differ between groups.

INTERPRETATION

Addition of monthly intermittent preventive treatment with dihydroartemisinin-piperaquine to the standard of care with daily unsupervised co-trimoxazole in areas of high antifolate resistance substantially improves malaria chemoprevention in pregnant women living with HIV on dolutegravir-based cART and should be considered for policy.

FUNDING

European and Developing Countries Clinical Trials Partnership 2; UK Joint Global Health Trials Scheme (UK Foreign, Commonwealth and Development Office; Medical Research Council; National Institute for Health Research; Wellcome); and Swedish International Development Cooperation Agency.

Post-discharge malaria chemoprevention in children admitted with severe anaemia in malaria-endemic settings in Africa: a systematic review and individual patient data meta-analysis of randomised controlled trials

BACKGROUND

Severe anaemia is associated with high in-hospital mortality among young children. In malaria-endemic areas, surviving children also have an increased risk of mortality or readmission after hospital discharge. We conducted a systematic review and individual patient data meta-analysis to determine the efficacy of monthly post-discharge malaria chemoprevention in children recovering from severe anaemia.

METHODS

This analysis was conducted according to PRISMA-IPD guidelines. We searched multiple databases on Aug 28, 2023, without date or language restrictions, for randomised controlled trials comparing monthly post-discharge malaria chemoprevention with placebo or standard of care among children (aged <15 years) admitted with severe anaemia in malaria-endemic Africa. Trials using daily or weekly malaria prophylaxis were not eligible. The investigators from all eligible trials shared pseudonymised datasets, which were standardised and merged for analysis. The primary outcome was all-cause mortality during the intervention period. Analyses were performed in the modified intention-to-treat population, including all randomly assigned participants who contributed to the endpoint. Fixed-effects two-stage meta-analysis of risk ratios (RRs) was used to generate pooled effect estimates for mortality. Recurrent time-to-event data (readmissions or clinic visits) were analysed using one-stage mixed-effects Prentice-Williams-Peterson total-time models to obtain hazard ratios (HRs). This study is registered with PROSPERO, CRD42022308791.

FINDINGS

Our search identified 91 articles, of which 78 were excluded by title and abstract, and a further ten did not meet eligibility criteria. Three double-blind, placebo-controlled trials, including 3663 children with severe anaemia, were included in the systematic review and meta-analysis; 3507 (95·7%) contributed to the modified intention-to-treat analysis. Participants received monthly sulfadoxine-pyrimethamine until the end of the malaria transmission season (mean 3·1 courses per child [range 1-6]; n=1085; The Gambia), monthly artemether-lumefantrine given at the end of weeks 4 and 8 post discharge (n=1373; Malawi), or monthly dihydroartemisinin-piperaquine given at the end of weeks 2, 6, and 10 post discharge (n=1049; Uganda and Kenya). During the intervention period, post-discharge malaria chemoprevention was associated with a 77% reduction in mortality (RR 0·23 [95% CI 0·08-0·70], p=0·0094, I2=0%) and a 55% reduction in all-cause readmissions (HR 0·45 [95% CI 0·36-0·56], p<0·0001) compared with placebo. The protective effect was restricted to the intervention period and was not sustained after the direct pharmacodynamic effect of the drugs had waned. The small number of trials limited our ability to assess heterogeneity, its sources, and publication bias.

INTERPRETATION

In malaria-endemic Africa, post-discharge malaria chemoprevention reduces mortality and readmissions in recently discharged children recovering from severe anaemia. Post-discharge malaria chemoprevention could be a valuable strategy for the management of this group at high risk. Future research should focus on methods of delivery, options to prolong the protection duration, other hospitalised groups at high risk, and interventions targeting non-malarial causes of post-discharge morbidity.

FUNDING

The Research-Council of Norway and the Bill-&-Melinda-Gates-Foundation through the Worldwide-Antimalarial-Research-Network.

Safety and tolerability of repeated doses of dihydroartemisinin-piperaquine for intermittent preventive treatment of malaria in pregnancy: a systematic review and an aggregated data meta-analysis of randomized controlled trials

BACKGROUND

Malaria infection during pregnancy is an important cause of maternal and infant mortality and morbidity with the greatest effect being concentrated in sub-Saharan Africa. In areas of moderate to high malaria transmission, the World Health Organization (WHO) recommends the administration of intermittent preventive treatment of malaria in pregnancy (IPTp) using sulfadoxine-pyrimethamine (SP) to be given to all pregnant women at each scheduled antenatal care visit at monthly intervals. However, there is concern that increased resistance has compromised its effectiveness. This has led to a need for evaluation of alternatives to SP for IPTp with dihydroartemisinin-piperaquine (DP) emerging as a very promising candidate. Thus, this systematic review and aggregated data meta-analysis was conducted to establish the safety and tolerability of repeated doses with DP in IPTp.

METHODS

A systematic review and aggregated data meta-analysis of randomized controlled trials (RCTs) was performed by searching electronic databases of PubMed, Science Direct, ClinicalTrials.gov and Google Scholar. RCTs comparing IPTp DP versus recommended standard treatment for IPTp with these outcome measures were analyzed; change in QTc interval, serious adverse events (SAE), grade 3 or 4 adverse events possibly related to study drug and vomiting within 30 min after study drug administration. The search was performed up to 24th June 2023. Data was extracted from eligible studies and an aggregated data meta-analysis was carried out with data pooled as risk ratio (RR) with a 95% confidence interval (CI), using RevMan software (5.4). This study is registered with PROSPERO, CRD42022310041.

RESULTS

Six RCTs involving 7969 participants were included in this systematic review and aggregated data meta-analysis. The pooled analysis showed that DP was associated with a change from baseline of the QTc interval although this change was not associated with cardiotoxicity. There was no statistically significant difference in the risk of occurrence of SAEs among participants in both treatment groups (RR = 0.80, 95% CI [0.52-1.24], P = 0.32). However, significant difference was observed in grade 3 or 4 AEs possibly related to study drug where analysis showed that subjects on IPT DP were statistically significantly more likely to experience an AE possibly related to study drug than subjects on IPT SP (RR = 6.65, 95% CI [1.18-37.54], P = 0.03) and in vomiting within 30 min after study drug administration where analysis showed that the risk of vomiting is statistically significantly higher in subjects receiving IPT DP than in subjects receiving IPT SP (RR = 1.77, 95% CI [1.02-3.07], P = 0.04).

CONCLUSION

DP was associated with a higher risk of grade 3 or 4 AEs possibly related to study drug and a higher risk of vomiting within 30 min after study drug administration. However, these were experienced in a very small percentage of women and did not affect adherence to study drugs. DP was also better tolerated in these studies as compared to most alternatives that have been proposed to replace SP which have proved to be too poorly tolerated in IPTp use.

Fetal growth and birth weight are independently reduced by malaria infection and curable sexually transmitted and reproductive tract infections in Kenya, Tanzania, and Malawi: A pregnancy cohort study

OBJECTIVES

Malaria and sexually transmitted and reproductive tract infections (STIs/RTIs) are highly prevalent in sub-Saharan Africa and associated with poor pregnancy outcomes. We investigated the individual and combined effects of malaria and curable STIs/RTIs on fetal growth in Kenya, Tanzania, and Malawi.

METHODS

This study was nested within a randomized trial comparing monthly intermittent preventive treatment for malaria in pregnancy with sulfadoxine-pyrimethamine vs dihydroartemisinin-piperaquine, alone or combined with azithromycin. Fetal weight gain was assessed by serial prenatal ultrasound. Malaria was assessed monthly, and Treponema pallidum, Neisseria gonorrhoeae, Trichomonas vaginalis, Chlamydia trachomatis, and bacterial vaginosis at enrollment and in the third trimester. The effect of malaria and STIs/RTIs on fetal weight/birthweight Z-scores was evaluated using mixed-effects linear regression.

RESULTS

In total, 1435 pregnant women had fetal/birth weight assessed 3950 times. Compared to women without malaria or STIs/RTIs (n = 399), malaria-only (n = 267), STIs/RTIs only (n = 410) or both (n = 353) were associated with reduced fetal growth (adjusted mean difference in fetal/birth weight Z-score [95% confidence interval]: malaria = -0.18 [-0.31,-0.04], P = 0.01; STIs/RTIs = -0.14 [-0.26,-0.03], P = 0.01; both = -0.20 [-0.33,-0.07], P = 0.003). Paucigravidae experienced the greatest impact.

CONCLUSION

Malaria and STIs/RTIs are associated with poor fetal growth especially among paucigravidae women with dual infections. Integrated antenatal interventions are needed to reduce the burden of both malaria and STIs/RTIs.

Malaria in Pregnancy: Key Points for the Neonatologist

In malaria-endemic regions, infection with the malaria parasite Plasmodium during pregnancy has been identified as a key modifiable factor in preterm birth, the delivery of low-birthweight infants, and stillbirth. Compared with their nonpregnant peers, pregnant persons are at higher risk for malaria infection. Malaria infection can occur at any time during pregnancy, with negative effects for the pregnant person and the fetus, depending on the trimester in which the infection is contracted. Pregnant patients who are younger, in their first or second pregnancy, and those coinfected with human immunodeficiency virus are at increased risk for malaria. Common infection prevention measures during pregnancy include the use of insecticide-treated bed nets and the use of intermittent preventive treatment with monthly doses of antimalarials, beginning in the second trimester in pregnant patients in endemic areas. In all trimesters, artemisinin-combination therapies are the first-line treatment for uncomplicated falciparum malaria, similar to treatment in nonpregnant adults. The World Health Organization recently revised its recommendations, now listing the specific medication artemether-lumefantrine as first-line treatment for uncomplicated malaria in the first trimester. While strong prevention and detection methods exist, use of these techniques remains below global targets. Ongoing work on approaches to treatment and prevention of malaria during pregnancy remains at the forefront of global maternal child health research.

Effectiveness of Intermittent Screening and Treatment of Malaria in Pregnancy on Maternal and Birth Outcomes in Selected Districts in Rwanda: A Cluster Randomized Controlled Trial

BACKGROUND

Malaria during pregnancy can cause serious consequences including maternal anemia and low birthweight (LBW). Routine antenatal care (ANC) in Rwanda includes malaria symptom screening at each ANC visit. This cluster randomized controlled trial investigated whether adding intermittent screening with a malaria rapid diagnostic test at each routine ANC visit and treatment of positives during pregnancy (ISTp) is more effective than routine ANC for reducing malaria prevalence at delivery.

METHODS

Between September 2016 and June 2018, pregnant women initiating ANC at 14 health centers in Rwanda were enrolled into ISTp or control arms. All women received an insecticide-treated bed net at enrollment. Hemoglobin concentration, placental and peripheral parasitemia, newborn outcome, birthweight, and prematurity were assessed at delivery.

RESULTS

Nine hundred seventy-five women were enrolled in ISTp and 811 in the control group. Routine ANC plus ISTp did not significantly reduce polymerase chain reaction-confirmed placental malaria compared to control (adjusted relative risk [aRR], 0.94 [95% confidence interval {CI}, .59-1.50]; P = .799). ISTp had no impact on anemia (aRR, 1.08 [95% CI, .57-2.04]; P = .821). The mean birthweight of singleton newborns was not significantly different between arms (3054 g vs 3096 g, P = .395); however, women in the ISTp arm had a higher proportion of LBW (aRR, 1.59 [95% CI, 1.02-2.49]; P = .042).

CONCLUSIONS

This is the only study to compare ISTp to symptomatic screening at ANC in a setting where intermittent preventive treatment is not routinely provided. ISTp did not reduce the prevalence of malaria or anemia at delivery and was associated with an increased risk of LBW.

CLINICAL TRIALS REGISTRATION

NCT03508349.

Intermittent preventive treatment with Sulfadoxine pyrimethamine for malaria: a global overview and challenges affecting optimal drug uptake in pregnant women

Malaria in Pregnancy (MiP) leading to morbidity and mortality is a major public health problem that poses significant risk to pregnant women and their fetus. To cope with this alarming situation, administration of Sulfadoxine-pyrimethamine (SP) drugs to pregnant women as an intermittent preventive treatment (IPT) from 16 weeks of gestation is recommended by the World Health Organization (WHO) guidelines. We conducted a comprehensive search of published articles related to MiP in last 10 years with predefined keywords or their synonyms. The mapping of malaria in pregnant women showed a prevalence rate up to 35% in many countries. Although IPTp-SP has been implemented in endemic regions since several years but the IPTp-SP coverage percentage vary from country to country and continue to remain below the target of 80%. Major reasons for low IPTp-SP involve gestational age at first prenatal visit, level of education, place of residence, knowledge of IPTp-SP benefits, and use of antenatal services. Several challenges including the emergence of septuple and octuple SP-resistant parasites is reported from many countries which make the prophylactic use of IPTp-SP currently debatable. This narrative review addresses the barriers for optimal use of IPTp-SP and discusses alternative approaches to increase the use and effectiveness of SP intervention for preventing MiP. The COVID pandemic has drastically affected the public health disrupting the management of diseases worldwide. In view of this, a brief summary of COVID impact on MiP situation is also included.

Fetal sex and risk of pregnancy-associated malaria in Plasmodium falciparum-endemic regions: a meta-analysis

In areas of moderate to intense Plasmodium falciparum transmission, malaria in pregnancy remains a significant cause of low birth weight, stillbirth, and severe anaemia. Previously, fetal sex has been identified to modify the risks of maternal asthma, pre-eclampsia, and gestational diabetes. One study demonstrated increased risk of placental malaria in women carrying a female fetus. We investigated the association between fetal sex and malaria in pregnancy in 11 pregnancy studies conducted in sub-Saharan African countries and Papua New Guinea through meta-analysis using log binomial regression fitted to a random-effects model. Malaria infection during pregnancy and delivery was assessed using light microscopy, polymerase chain reaction, and histology. Five studies were observational studies and six were randomised controlled trials. Studies varied in terms of gravidity, gestational age at antenatal enrolment and bed net use. Presence of a female fetus was associated with malaria infection at enrolment by light microscopy (risk ratio 1.14 [95% confidence interval 1.04, 1.24]; P = 0.003; n = 11,729). Fetal sex did not associate with malaria infection when other time points or diagnostic methods were used. There is limited evidence that fetal sex influences the risk of malaria infection in pregnancy.

Coinfections of malaria and sexually transmitted and reproductive tract infections in pregnancy in sub-Saharan Africa: a systematic review and individual participant data meta-analysis protocol

INTRODUCTION

Malaria infection and curable sexually transmitted infections and reproductive tract infections (STIs/RTIs) adversely impact pregnancy outcomes. In sub-Saharan Africa, the prevalence of malaria and curable STIs/RTIs is high and, where coinfection is common, combination interventions may be needed to improve pregnancy outcomes. The aim of this systematic review is to estimate the prevalence of malaria and curable STI/RTI coinfection during pregnancy, risk factors for coinfection and prevalence of associated adverse pregnancy outcomes.

METHODS AND ANALYSIS

We will use three electronic databases, PubMed, EMBASE and Malaria in Pregnancy Library to identify studies involving pregnant women attending routine antenatal care facilities in sub-Saharan Africa and reporting malaria and curable STI/RTI test results, published in any language since 2000. We will search databases in the second quarter of 2023 and repeat the search before completion of our analyses. The first two authors will screen titles and abstracts, selecting studies that meet inclusion criteria and qualify for full-text screening. If agreement on inclusion/exclusion cannot be reached, the last author will serve as arbiter. We will extract data from eligible publications for a study-level meta-analysis. We will contact research groups of included studies and request individual participant data for meta-analysis. The first two authors will conduct a quality appraisal of included studies using the GRADE system. The last author will adjudicate if the first two authors do not agree on any appraisals. We will conduct sensitivity analyses to test the robustness of effect estimates over time (by decade and half-decade periods), geography (East/Southern Africa vs West/Central Africa), gravidity (primigravidae, secundigravidae, multigravidae), treatment type and dosing frequency, and malaria transmission intensity.

ETHICS AND DISSEMINATION

We obtained ethics approval from the London School of Hygiene & Tropical Medicine (LSHTM Ethics Ref: 26167). Results of this study will be disseminated via peer-reviewed publication and presentation at scientific conferences.

PROSPERO REGISTRATION NUMBER

CRD42021224294.

Effect of monthly intermittent preventive treatment with dihydroartemisinin-piperaquine with and without azithromycin versus monthly sulfadoxine-pyrimethamine on adverse pregnancy outcomes in Africa: a double-blind randomised, partly placebo-controlled trial

BACKGROUND

Intermittent preventive treatment in pregnancy (IPTp) with dihydroartemisinin-piperaquine is more effective than IPTp with sulfadoxine-pyrimethamine at reducing malaria infection during pregnancy in areas with high-grade resistance to sulfadoxine-pyrimethamine by Plasmodium falciparum in east Africa. We aimed to assess whether IPTp with dihydroartemisinin-piperaquine, alone or combined with azithromycin, can reduce adverse pregnancy outcomes compared with IPTp with sulfadoxine-pyrimethamine.

METHODS

We did an individually randomised, double-blind, three-arm, partly placebo-controlled trial in areas of high sulfadoxine-pyrimethamine resistance in Kenya, Malawi, and Tanzania. HIV-negative women with a viable singleton pregnancy were randomly assigned (1:1:1) by computer-generated block randomisation, stratified by site and gravidity, to receive monthly IPTp with sulfadoxine-pyrimethamine (500 mg of sulfadoxine and 25 mg of pyrimethamine for 1 day), monthly IPTp with dihydroartemisinin-piperaquine (dosed by weight; three to five tablets containing 40 mg of dihydroartemisinin and 320 mg of piperaquine once daily for 3 consecutive days) plus a single treatment course of placebo, or monthly IPTp with dihydroartemisinin-piperaquine plus a single treatment course of azithromycin (two tablets containing 500 mg once daily for 2 consecutive days). Outcome assessors in the delivery units were masked to treatment group. The composite primary endpoint was adverse pregnancy outcome, defined as fetal loss, adverse newborn baby outcomes (small for gestational age, low birthweight, or preterm), or neonatal death. The primary analysis was by modified intention to treat, consisting of all randomised participants with primary endpoint data. Women who received at least one dose of study drug were included in the safety analyses. This trial is registered with ClinicalTrials.gov, NCT03208179.

FINDINGS

From March-29, 2018, to July 5, 2019, 4680 women (mean age 25·0 years [SD 6·0]) were enrolled and randomly assigned: 1561 (33%; mean age 24·9 years [SD 6·1]) to the sulfadoxine-pyrimethamine group, 1561 (33%; mean age 25·1 years [6·1]) to the dihydroartemisinin-piperaquine group, and 1558 (33%; mean age 24·9 years [6.0]) to the dihydroartemisinin-piperaquine plus azithromycin group. Compared with 335 (23·3%) of 1435 women in the sulfadoxine-pyrimethamine group, the primary composite endpoint of adverse pregnancy outcomes was reported more frequently in the dihydroartemisinin-piperaquine group (403 [27·9%] of 1442; risk ratio 1·20, 95% CI 1·06-1·36; p=0·0040) and in the dihydroartemisinin-piperaquine plus azithromycin group (396 [27·6%] of 1433; 1·16, 1·03-1·32; p=0·017). The incidence of serious adverse events was similar in mothers (sulfadoxine-pyrimethamine group 17·7 per 100 person-years, dihydroartemisinin-piperaquine group 14·8 per 100 person-years, and dihydroartemisinin-piperaquine plus azithromycin group 16·9 per 100 person-years) and infants (sulfadoxine-pyrimethamine group 49·2 per 100 person-years, dihydroartemisinin-piperaquine group 42·4 per 100 person-years, and dihydroartemisinin-piperaquine plus azithromycin group 47·8 per 100 person-years) across treatment groups. 12 (0·2%) of 6685 sulfadoxine-pyrimethamine, 19 (0·3%) of 7014 dihydroartemisinin-piperaquine, and 23 (0·3%) of 6849 dihydroartemisinin-piperaquine plus azithromycin treatment courses were vomited within 30 min.

INTERPRETATION

Monthly IPTp with dihydroartemisinin-piperaquine did not improve pregnancy outcomes, and the addition of a single course of azithromycin did not enhance the effect of monthly IPTp with dihydroartemisinin-piperaquine. Trials that combine sulfadoxine-pyrimethamine and dihydroartemisinin-piperaquine for IPTp should be considered.

FUNDING

European & Developing Countries Clinical Trials Partnership 2, supported by the EU, and the UK Joint-Global-Health-Trials-Scheme of the Foreign, Commonwealth and Development Office, Medical Research Council, Department of Health and Social Care, Wellcome, and the Bill-&-Melinda-Gates-Foundation.

Sub-microscopic Plasmodium falciparum parasitaemia, dihydropteroate synthase (dhps) resistance mutations to sulfadoxine-pyrimethamine, transmission intensity and risk of malaria infection in pregnancy in Mount Cameroon Region

BACKGROUND

Plasmodium falciparum resistance to intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) continues to spread throughout sub-Saharan Africa. This study assessed the occurrence of microscopic and sub-microscopic P. falciparum parasitaemia, dihydropteroate synthase mutations associated with resistance to SP and maternal anaemia in the Mount Cameroon area.

METHODS

Consenting pregnant women living in semi-rural and semi-urban/urbanized settings were enrolled in this cross-sectional study. Socio-demographic, antenatal and clinical data were documented. Microscopic and sub-microscopic parasitaemia were diagnosed using peripheral blood microscopy and nested polymerase chain reaction (PCR) respectively. The dhps mutations were genotyped by restriction fragment length polymorphism analysis. The presence of A437G, K540E, and A581G was considered a marker for high-level resistance. Haemoglobin levels and anaemia status were determined.

RESULTS

Among the women, the prevalence of microscopic and sub-microscopic P. falciparum infection were 7.7% (67/874) and 18.6% (93/500) respectively. Predictors of microscopic infection were younger age (< 21 years) (AOR = 2.89; 95% CI 1.29-6.46) and semi-rural settings (AOR = 2.27; 95% CI 1.31-3.96). Determinants of sub-microscopic infection were the rainy season (AOR, 3.01; 95% CI 1.77-5.13), primigravidity (AOR = 0.45; 95% CI 0.21-0.94) and regular ITN usage (AOR = 0.49; 95% CI 0.27-0.90). Of the145 P. falciparum isolates genotyped, 66.9% (97) carried mutations associated with resistance to SP; 33.8% (49), 0%, 52.4% (76) and 19.3% (28) for A437G, K540E, A581G and A437G + A581G respectively. The A581G mutation was associated with ≥ 3 SP doses evident only among sub-microscopic parasitaemia (P = 0.027) and multigravidae (P = 0.009). Women with microscopic infection were more likely from semi-rural settings (AOR = 7.09; 95% CI 2.59-19.42), to report history of fever (AOR = 2.6; 95% CI 1.07-6.31), to harbour parasites with double resistant mutations (AOR = 6.65; 95% CI 1.85-23.96) and were less likely to have received 2 SP doses (AOR = 0.29; 95% CI 1.07-6.31). Microscopic infection decreased Hb levels more than sub-microscopic infection.

CONCLUSION

The occurrence of sub-microscopic P. falciparum parasites resistant to SP and intense malaria transmission poses persistent risk of malaria infection during pregnancy in the area. ITN usage and monitoring spread of resistance are critical.

Superiority trial of intermittent treatment with dihydroartemisinin–piperaquine versus sulfadoxine–pyrimethamine for the prevention of malaria during pregnancy

Background

Malaria in pregnancy is responsible for various adverse maternal and birth outcomes. The emerging resistance to sulfadoxine–pyrimethamine (SP) raises important concerns about its use for intermittent preventive treatment in pregnancy (IPTp) in Africa. This trial aimed to assess the efficacy and safety of IPTp with dihydroartemisinin–piperaquine (DP) as an alternative to IPTp with SP.

Results

The double-blind, randomized, and controlled superiority trial was conducted between July 2020 and June 2021. A total of 250 women were enrolled and randomly assigned to receive SP (n = 125) or DP (n = 125). Two hundred and six (82.4%) participants that contributed to the outcomes were included in the modified intention-to-treat (ITT) analysis, while 84 participants that completed the three courses of the study drugs were included in the per protocol (PP) analysis. The ITT analysis results showed that the incidence of histopathologically confirmed placental malaria was nonsignificantly higher in the DP group compared with the SP group (62.5% vs. 51.1%, P = 0.098). After adjusting for confounders, the risk of histopathologically confirmed placental malaria was also nonsignificantly higher in the DP group (Adjusted Relative Risk [RR] = 1.27, 95% CI 0.94–1.71) compared with the SP group. In contrast, the risk of a low APGAR score was significantly lower in the DP group (RR = 0.45, 95% CI 0.38–0.52) compared with the SP group. Also, the risk of a composite adverse birth outcome (low birth weight or preterm delivery or neonates small for the gestational age) was nonsignificantly lower in the DP group (Adjusted RR = 0.82, 95% CI 0.55–1.21) compared with the SP group. Both drugs were well tolerated, although nausea and vomiting occurred in a significant number of participants in the SP group.

Conclusions

A three-course IPTp with DP was safe and was not found to be superior to IPTp with SP in the prevention of placental malaria. Although IPTp with DP was associated with a significant lower risk of low APGAR score and nonsignificant lower risks of other adverse birth outcomes compared with IPTp with SP.

Trial registration

PACTR, PACTR202002644579177. Registered 20 February 2020, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9753.

Impact of prophylactic antimalarials in pregnant women living with Human Immunodeficiency Virus on birth outcomes in Botswana

OBJECTIVES

Until late 2015, Botswana recommended preventive treatment for pregnant women in malarial regions with chloroquine and proguanil (CP). The guideline change provided an opportunity to evaluate CP and adverse birth outcomes.

METHODS

The Tsepamo Study performed birth outcomes surveillance at large delivery centres throughout Botswana. We evaluated adverse birth outcomes from 2015 to 2017 at three hospitals where 93% of CP use was recorded. Outcomes included neonatal death (NND), small for gestational age (SGA), very SGA, stillbirth (SB), preterm delivery (PTD) and very PTD. Logistic regression analysis (unadjusted and adjusted) was conducted for each adverse birth outcome.

RESULTS

During the study period, 5883 (26%) of 23,033 deliveries were exposed to CP, with the majority (65%) in the most malaria-endemic region. At this site, there was a trend or an association between CP use and reduction of three adverse birth outcomes: PTD (aOR 0.85, 95% CI 0.76-0.96), vPTD (aOR 0.83, 95% CI 0.68-1.01) and NND (aOR 0.65, 95% CI 0.42-1.00). However, at the least malaria-endemic site, the association was in the opposite direction for SB (aOR 1.54, 95% CI 1.08-2.22), SGA (aOR 1.24, 95% CI 1.06-1.44) and vSGA (aOR 1.42, 95% CI 1.14-1.77). The association between CP and reduced PTD was present among women without HIV (aOR 0.77, 95% CI 0.67-0.89) but not among women with HIV (aOR 1.09, 95% CI 0.78-1.35).

CONCLUSIONS

Antimalarial prophylaxis was associated with improved birth outcomes in the most malaria-endemic region of Botswana, but not elsewhere. This finding supports current WHO guidance to use prophylaxis strategies among pregnant women in highly malaria-endemic regions. Further studies of the risks and benefits of specific antimalarial regimens in pregnancy are warranted, particularly in areas with lower incidence of malaria.

Factors Affecting the Performance of HRP2-Based Malaria Rapid Diagnostic Tests

The recent COVID-19 pandemic has profoundly impacted global malaria elimination programs, resulting in a sharp increase in malaria morbidity and mortality. To reduce this impact, unmet needs in malaria diagnostics must be addressed while resuming malaria elimination activities. Rapid diagnostic tests (RDTs), the unsung hero in malaria diagnosis, work to eliminate the prevalence of Plasmodium falciparum malaria through their efficient, cost-effective, and user-friendly qualities in detecting the antigen HRP2 (histidine-rich protein 2), among other proteins. However, the testing mechanism and management of malaria with RDTs presents a variety of limitations. This paper discusses the numerous factors (including parasitic, host, and environmental) that limit the performance of RDTs. Additionally, the paper explores outside factors that can hinder RDT performance. By understanding these factors that affect the performance of HRP2-based RDTs in the field, researchers can work toward creating and implementing more effective and accurate HRP2-based diagnostic tools. Further research is required to understand the extent of these factors, as the rapidly changing interplay between parasite and host directly hinders the effectiveness of the tool.

Drugs for Intermittent Preventive Treatment of Malaria in Pregnancy: Current Knowledge and Way Forward

Malaria infection during pregnancy is an important driver of maternal and neonatal health in endemic countries. Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended for malaria prevention at each scheduled antenatal care visit, starting at the second trimester, in areas of high and moderate transmission. However, the increased resistance to SP in some endemic areas challenges its effectiveness. Furthermore, SP is contraindicated in the first trimester of pregnancy and in HIV-infected women on co-trimoxazole prophylaxis due to potential drug–drug interactions. Thus, in recent last decades, several studies evaluated alternative drugs that could be used for IPTp. A comprehensive literature review was conducted to summarize the evidence on the efficacy and safety of antimalarial drugs being evaluated for IPTp. Chloroquine, amodiaquine, mefloquine and azithromycin as IPTp have proven to be worse tolerated than SP. Mefloquine was found to increase the risk of mother-to-child transmission of HIV. Dihydroartemisin-piperaquine currently constitutes the most promising IPTp drug alternative; it reduced the prevalence of malaria infection, and placental and clinical malaria in studies among HIV-uninfected women, and it is currently being tested in HIV-infected women. Research on effective antimalarial drugs that can be safely administered for prevention to pregnant women should be prioritized. Malaria prevention in the first trimester of gestation and tailored interventions for HIV-infected women remain key research gaps to be addressed.

Intermittent screening and treatment for malaria complementary to routine immunisation in the first year of life in Papua, Indonesia: a cluster randomised superiority trial

BACKGROUND

In Papua (Indonesia), infants with P. falciparum and/or P. vivax malaria are at risk of severe anaemia and death. We hypothesized that in an area of high malaria transmission, intermittent screening and treatment of infants with malaria (ISTi) will reduce morbidity compared to passive case detection (PCDi).

METHODS

We conducted a cluster randomised, open label, superiority trial. A total of 21 clusters of village health posts (VHP) were randomised 1:1 to either IST for infants coinciding with 4 routine immunisation visits or PCDi. Healthy term infants born to consenting mothers enrolled into a maternal malaria cluster randomised trial were included in the study and followed for 12 months. Point of care malaria rapid diagnostic tests were used to detect peripheral parasitaemia at 2, 3, 4 and 9 months old in all infants in ISTi clusters and when symptomatic in PCDi clusters. Infants with detected peripheral parasitaemia were treated with dihydroartemisinin-piperaquine. The co-primary outcomes were the incidence rate of clinical malaria in the first year of life and the prevalence of parasitaemia at age 12 months. The incidence rate ratio and prevalence ratio between ISTi and PCDi were estimated using mixed-effects Poisson and log-binomial regression modelling (accounting for clustering at VHP level).

RESULTS

Between May 2014 and February 2017, 757 infants were enrolled into the study, 313 into 10 ISTi clusters, and 444 into 11 PCDi clusters. Overall, 132 episodes of parasitaemia were detected, of whom 17 (12.9%) were in symptomatic infants. Over 12 months, the incidence rate (IR) of clinical malaria was 24 [95% CI, 10-50] per 1000 children-years at risk in the ISTi arm and 19 [95% CI, 8,38] per 1000 children-years in the PCDi arm (adjusted incidence rate ratio [aIRR] 1.77 [95% CI, 0.62-5.01]; p = 0.280). The prevalence of parasitaemia at 12 months was 13% (33/254) in the IST clusters and 15% (57/379) in the PCD clusters (adjusted prevalence ratio (aPR) = 0.92 (95% CI, 0.70-1.21), p = 0.55). There was no difference in the risk of anaemia between treatment arms.

CONCLUSIONS

In high malaria transmission area outside of Africa, our study suggests that compared to PCDi, ISTi offers no significant benefit in reducing the risk of clinical malaria in infants born to women receiving effective protection from malaria during pregnancy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02001428 , registered on 20 Nov 2013.

Malaria chemoprevention and drug resistance: a review of the literature and policy implications

Chemoprevention strategies reduce malaria disease and death, but the efficacy of anti-malarial drugs used for chemoprevention is perennially threatened by drug resistance. This review examines the current impact of chemoprevention on the emergence and spread of drug resistant malaria, and the impact of drug resistance on the efficacy of each of the chemoprevention strategies currently recommended by the World Health Organization, namely, intermittent preventive treatment in pregnancy (IPTp); intermittent preventive treatment in infants (IPTi); seasonal malaria chemoprevention (SMC); and mass drug administration (MDA) for the reduction of disease burden in emergency situations. While the use of drugs to prevent malaria often results in increased prevalence of genetic mutations associated with resistance, malaria chemoprevention interventions do not inevitably lead to meaningful increases in resistance, and even high rates of resistance do not necessarily impair chemoprevention efficacy. At the same time, it can reasonably be anticipated that, over time, as drugs are widely used, resistance will generally increase and efficacy will eventually be lost. Decisions about whether, where and when chemoprevention strategies should be deployed or changed will continue to need to be made on the basis of imperfect evidence, but practical considerations such as prevalence patterns of resistance markers can help guide policy recommendations.

The positive effect of malaria IPTp-SP on birthweight is mediated by gestational weight gain but modifiable by maternal carriage of enteric pathogens

BACKGROUND

Poor pregnancy and birth outcomes are common in sub-Saharan Africa and have complex aetiologies. Sulfadoxine-pyrimethamine (SP), given for intermittent preventive therapy of malaria in pregnancy (IPTp), is one of few existing interventions that improves outcomes of both mother and baby despite widespread SP-resistant malaria. Compelling evidence exists that malaria-independent pathways contribute to this protective effect, but the exact sources of non anti-malarial protection remained unknown. We hypothesized that the beneficial effect of SP on birthweight is mediated by SP activity on maternal factors, including increased gestational weight gain and antibiotic activity on pathogens in the maternal gut.

METHODS

Expectant mothers from a larger randomized control trial comparing the efficacy of IPTp-SP to IPTp with dihydroartemisinin-piperaquine (DP) were also enrolled in this sub-study study at their first antenatal care visit before commencement of IPTp (n = 105). Participants were followed monthly until delivery. Weights and mid-to-upper-arm circumferences (MUAC) were recorded. Monthly stool samples were collected and screened for five Escherichia coli pathotypes, Shigella spp., Vibrio cholerae, Salmonella, Campylobacter coli/jejuni, and three protozoa (Giardia spp., Entameba histolytica, and Cryptosporidium spp.) using previously validated molecular assays.

FINDINGS

IPTp-SP vs. IPTP-DP was associated with higher maternal gestational weight gain (GWG) and nutritional indicators (MUAC and body-mass index, BMI). GWG was found to be a mediator of the birthweight and IPTp-SP relationship, as the birthweight of SP infants, but not DP infants, varied according to maternal GWG. The burden of maternal enteric infections was high. The three most commonly observed pathogens were enteroaggregative E. coli (EAEC), atypical enteropathogenic E.coli/enterohaemorrhagic E. coli (aEPEC/EHEC), and typical enteropathogenic E.coli (tEPEC). We found that SP reduced the prevalence of EAEC in a dose-dependent manner. After 3 or more doses, SP-recipients were 90% less likely to be infected with EAEC compared to DP-recipients (ORadj = 0.07, CI95 = 0.12, 0.39, p = 0.002). Compared to DP, this coincided with higher maternal gestational weight gain (GWG) and nutritional indicators (MUAC and body-mass index, BMI). The beneficial effect of SP on maternal GWG, MUAC and BMI, was lower if SP mothers had detectable EAEC, aEPEC/EHEC, tEPEC, and LT-ETEC at baseline. Maternal EAEC and tEPEC at baseline associated with lower birthweight for babies of both SP mothers and DP mothers. When comparing IPTp regimens, the positive effect of SP on birthweight compared to DP was only observed for infants of women who did not test positive for EAEC at baseline (adjusted mean birthweight difference SP vs. DP = 156.0 g, CI95 = -18.0 g, 336.9 g, p = 0.087), though confidence intervals crossed the null.

INTERPRETATION

Our findings indicate that in pregnant Malawian women, IPTp-SP vs. IPTp-DP is consistently associated with higher MUAC, BMI, and GWG following the WHO-recommended regimen of at least 3 doses, but carriage of maternal gut pathogens before initiation of IPTp lessens this effect. Because GWG was a mediator of the association between birthweight and SP, we show that SP's previously proven positive effect on birthweight is by promoting maternal weight gain. Overall, our results present one plausible pathway SP exerts malaria-independent protection against poor birth outcomes in the context of its waning antimalarial activity and warrants further investigation.

FUNDING

A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

Performance and utility of more highly sensitive malaria rapid diagnostic tests

Background

A new more highly sensitive rapid diagnostic test (HS-RDT) for Plasmodium falciparum malaria (Alere™/Abbott Malaria Ag P.f RDT [05FK140], now called NxTek™ Eliminate Malaria Ag Pf) was launched in 2017. The test has already been used in many research studies in a wide range of geographies and use cases.

Methods

In this study, we collate all published and available unpublished studies that use the HS-RDT and assess its performance in (i) prevalence surveys, (ii) clinical diagnosis, (iii) screening pregnant women, and (iv) active case detection. Two individual-level data sets from asymptomatic populations are used to fit logistic regression models to estimate the probability of HS-RDT positivity based on histidine-rich protein 2 (HRP2) concentration and parasite density. The performance of the HS-RDT in prevalence surveys is estimated by calculating the sensitivity and positive proportion in comparison to polymerase chain reaction (PCR) and conventional malaria RDTs.

Results

We find that across 18 studies, in prevalence surveys, the mean sensitivity of the HS-RDT is estimated to be 56.1% (95% confidence interval [CI] 46.9–65.4%) compared to 44.3% (95% CI 32.6–56.0%) for a conventional RDT (co-RDT) when using nucleic acid amplification techniques as the reference standard. In studies where prevalence was estimated using both the HS-RDT and a co-RDT, we found that prevalence was on average 46% higher using a HS-RDT compared to a co-RDT. For use in clinical diagnosis and screening pregnant women, the HS-RDT was not significantly more sensitive than a co-RDT.

Conclusions

Overall, the evidence presented here suggests that the HS-RDT is more sensitive in asymptomatic populations and could provide a marginal improvement in clinical diagnosis and screening pregnant women. Although the HS-RDT has limited temperature stability and shelf-life claims compared to co-RDTs, there is no evidence to suggest, given this test has the same cost as current RDTs, it would have any negative impacts in terms of malaria misdiagnosis if it were widely used in all four population groups explored here.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-07023-5.

Trends of malaria infection in pregnancy in Ghana over the past two decades: a review

Background

There has been a global decline in malaria transmission over the past decade. However, not much is known of the impact of this observation on the burden of malaria infection in pregnancy in endemic regions including Ghana. A narrative review was undertaken to help describe trends in malaria infection in pregnancy in Ghana. Among others, such information is important in showing any progress made in malaria in pregnancy control.

Methods

To describe trends in pregnancy-associated malaria infection in Ghana, a search and review of literature reporting data on the prevalence of asymptomatic Plasmodium falciparum infection in pregnancy was conducted.

Results

Thirty-six (36) studies, conducted over 1994–2019, were included in the review. In the northern savannah zone with largely seasonal malaria transmission, prevalence appeared to reduce from about 50–60% in 1994–2010 to 13–26% by 2019. In the middle transitional/forest zone, where transmission is perennial with peaks in the rainy season, prevalence apparently reduced from 60% in the late 1990 s to about 5–20% by 2018. In the coastal savannah area, there was apparent reduction from 28 to 35% in 2003–2010 to 5–11% by 2018–2019. The burden of malaria infection in pregnancy continues to be highest among teenagers and younger-aged pregnant women and paucigravidae.

Conclusions

There appears to be a decline in asymptomatic parasite prevalence in pregnancy in Ghana though this has not been uniform across the different transmission zones. The greatest declines were noticeably in urban settings. Submicroscopic parasitaemia remains a challenge for control efforts. Further studies are needed to evaluate the impact of the reduced parasite prevalence on maternal anaemia and low birthweight and to assess the local burden of submicroscopic parasitaemia in relation to pregnancy outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-021-04031-3.

Prevention of malaria in pregnancy: The threat of sulfadoxine-pyrimethamine resistance

Malaria infection in pregnancy can lead to adverse outcomes for both the pregnant person and fetus. The administration of intermittent preventative therapy (IPTp) with sulfadoxine-pyrimethamine (SP) during pregnancy (IPTp-SP) improves outcomes, including severe maternal anemia, placental malaria infection, and low infant birth weight. The WHO recommends IPTp-SP for pregnant individuals living in areas of moderate or high malaria transmission in Africa. The current regimen consists of two or more doses of SP starting as early as possible in the second trimester, at least 1 month apart. Unfortunately, rising Plasmodium falciparum SP resistance throughout Africa threatens to erode the benefits of SP. Recent studies have shown a decrease in IPTp-SP efficacy in areas with high SP resistance. Thus, there is an urgent need to identify new drug regimens that can be used for intermittent preventative therapy in pregnancy. In this review, we discuss recent data on P. falciparum SP resistance in Africa, the effect of resistance on IPTp-SP, and studies of alternative IPTp regimens. Finally, we present a framework for the ideal pharmacokinetic and pharmacodynamic properties for future IPTp regimens.

Efficacy and Safety of Artemisinin-Based Combination Therapy for the Treatment of Uncomplicated Malaria in Pregnant Women: A Systematic Review and Meta-Analysis

Introduction

Malaria is one of the infectious diseases with substantial risks for pregnant women, the fetus and the newborn child. Thus, prevention and treatment of malaria with safe and effective drugs is of paramount importance. Pregnant women are mostly excluded from clinical trials, and systematic approaches of pharmacovigilance in pregnancy are limited. This means the safety and efficacy of antimalarial agents during pregnancy are unclear.

Purpose

This study was designed to carry out a systematic review and aggregate data meta-analysis of literature published on efficacy and safety of artemisinin-based combination therapy (ACT) for uncomplicated malaria in pregnant women.

Methods

A search of literature published between 1998 to 2020 on efficacy and safety of artemisinin-based combination therapy (ACT) in pregnant women was made using Cochrane Library, Medline and the Malaria in Pregnancy Consortium Library. Data were extracted independently by two reviewers, and any discrepancies were resolved by consensus. Meta-analysis was carried out using Open Meta-Analyst software. Random effects model was applied, and the heterogeneity of studies was evaluated using Higgins I².

Results

Twenty-four studies that fulfilled the inclusion criteria were included in the final assessment. Overall, days 28 to 63 malaria treatment success rate was 96.1%. Overall days 28 to 63 cure rates for AL, AS+AQ, AS+MQ, DHA+PQ, AS+ATQ+PG and AS+SP were 95.1%, 92.2%, 97.0%,94.3%, 96.5% and 97.4%, respectively. Comparison of ACTs with non-ACTs revealed that the risk of treatment failure was substantially lower in patients treated with ACTs than with non-ACTs (risk ratio 0.20, 95% C.I. 0.09–0.43). The overall prevalences of miscarriage, stillbirth and congenital anomalies were 0.3%, 2.1% and 1.0%, respectively, and found to be comparable among various ACTs. There was comparable tolerability across ACTs during pregnancy.

Conclusion

ACTs demonstrated a high cure rate, safety and tolerability against Plasmodium falciparum infection in pregnant women. The higher treatment success and comparable tolerability could be used as an input for decision makers to support the continued usage of ACTs for treatment of uncomplicated falciparum malaria in pregnant women.

Evaluation of the safety and efficacy of dihydroartemisinin-piperaquine for intermittent preventive treatment of malaria in HIV-infected pregnant women: protocol of a multicentre, two-arm, randomised, placebo-controlled, superiority clinical trial (MAMAH project)

INTRODUCTION

Malaria infection during pregnancy is an important driver of maternal and neonatal health especially among HIV-infected women. Intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine is recommended for malaria prevention in HIV-uninfected women, but it is contraindicated in those HIV-infected on cotrimoxazole prophylaxis (CTXp) due to potential adverse effects. Dihydroartemisinin-piperaquine (DHA-PPQ) has been shown to improve antimalarial protection, constituting a promising IPTp candidate. This trial's objective is to determine if monthly 3-day IPTp courses of DHA-PPQ added to daily CTXp are safe and superior to CTXp alone in decreasing the proportion of peripheral malaria parasitaemia at the end of pregnancy.

METHODS AND ANALYSIS

This is a multicentre, two-arm, placebo-controlled, individually randomised trial in HIV-infected pregnant women receiving CTXp and antiretroviral treatment. A total of 664 women will be enrolled at the first antenatal care clinic visit in sites from Gabon and Mozambique. Participants will receive an insecticide-treated net, and they will be administered monthly IPTp with DHA-PPQ or placebo (1:1 ratio) as directly observed therapy from the second trimester of pregnancy. Primary study outcome is the prevalence of maternal parasitaemia at delivery. Secondary outcomes include prevalence of malaria-related maternal and infant outcomes and proportion of adverse perinatal outcomes. Participants will be followed until 6 weeks after the end of pregnancy and their infants until 1 year of age to also evaluate the impact of DHA-PPQ on mother-to-child transmission of HIV. The analysis will be done in the intention to treat and according to protocol cohorts, adjusted by gravidity, country, seasonality and other variables associated with malaria.

ETHICS AND DISSEMINATION

The protocol was reviewed and approved by the institutional and national ethics committees of Gabon and Mozambique and the Hospital Clinic of Barcelona. Project results will be presented to all stakeholders and published in open-access journals.

TRIAL REGISTRATION NUMBER

NCT03671109.

Safety and efficacy of intermittent presumptive treatment with sulfadoxine-pyrimethamine using rapid diagnostic test screening and treatment with dihydroartemisinin-piperaquine at the first antenatal care visit (IPTp-SP+): study protocol for a randomized controlled trial

Background

Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended by the World Health Organization for the prevention of malaria in pregnancy (MIP)-associated adverse outcomes in high burden areas. However, the efficacy of IPTp-SP has decreased in step with increasing parasite drug resistance. Suitable alternative strategies are needed.

Methods

This is a protocol for a phase IIIb open-label, two-armed randomized controlled superiority trial to assess the safety and efficacy of a hybrid approach to IPTp combining screening and treatment with dihydroartemisinin-piperaquine (DP) to the current IPTp-SP regimen at the first antenatal care clinic visit. Pregnant women without HIV infection and without signs or symptoms of malaria will be randomized to either standard IPTp-SP or hybrid IPTp-SP plus screening and treatment (IPTp-SP+). In the IPTp-SP+ arm, participants who screen positive by rapid diagnostic test for P. falciparum will be treated with DP at the first antenatal visit while those who screen negative will receive SP per current guidelines. All participants will be administered SP on days 35 and 63 and will be actively followed biweekly up to day 63 and then monthly until delivery. Infants will be followed until 1 year after delivery. The primary endpoint is incident PCR-confirmed MIP at day 42. Secondary endpoints include incident MIP at other time points, placental malaria, congenital malaria, hemoglobin trends, birth outcomes, and incidence of adverse events in infants up to the first birthday.

Discussion

A hybrid approach to IPTp that combines screening and treatment with an artemisinin-based combination therapy at the first visit with standard IPTp-SP is hypothesized to confer added benefit over IPTp-SP alone in a high malaria transmission area with prevalent SP resistant parasites.

Trial registration

Pan African Clinical Trials Registry 201905721140808. Registered retrospectively on 11 May 2019

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05745-0.

Intermittent screening and treatment with artemisinin-combination therapy versus intermittent preventive treatment with sulphadoxine-pyrimethamine for malaria in pregnancy: a systematic review and individual participant data meta-analysis of randomised clinical trials

BACKGROUND

In sub-Saharan Africa, the efficacy of intermittent preventive therapy in pregnancy with sulphadoxine-pyrimethamine (IPTp-SP) for malaria in pregnancy is threatened by parasite resistance. We conducted an individual-participant data (IPD) meta-analysis to assess the efficacy of intermittent screening with malaria rapid diagnostic tests (RDTs) and treatment of RDT-positive women with artemisinin-based combination therapy (ISTp-ACT) compared to IPTp-SP, and understand the importance of subpatent infections.

METHODS

We searched MEDLINE and the Malaria-in-Pregnancy Library on May 6, 2021 for trials comparing ISTp-ACT and IPTp-SP. Generalised linear regression was used to compare adverse pregnancy outcomes (composite of small-for-gestational-age, low birthweight (LBW), or preterm delivery) and peripheral or placental Plasmodium falciparum at delivery. The effects of subpatent (PCR-positive, RDT/microscopy-negative) infections were assessed in both arms pooled using multi-variable fixed-effect models adjusting for the number of patent infections. PROSPERO registration: CRD42016043789.

FINDINGS

Five trials conducted between 2007 and 2014 contributed (10,821 pregnancies), two from high SP-resistance areas where dhfr/dhps quintuple mutant parasites are saturated, but sextuple mutants are still rare (Kenya and Malawi), and three from low-resistance areas (West-Africa). Four trials contributed IPD data (N=10,362). At delivery, the prevalence of any malaria infection (relative risk [RR]=1.08, 95% CI 1.00-1.16, I2=67.0 %) and patent infection (RR=1.02, 0.61-1.16, I2=0.0%) were similar. Subpatent infections were more common in ISTp recipients (RR=1.31, 1.05-1.62, I2=0.0%). There was no difference in adverse pregnancy outcome (RR=1.00, 0.96-1.05; studies=4, N=9,191, I2=54.5%). Subpatent infections were associated with LBW (adjusted RR=1.13, 1.07-1.19), lower mean birthweight (adjusted mean difference=32g, 15-49), and preterm delivery (aRR=1.35, 1.15-1.57).

INTERPRETATION

ISTp-ACT was not superior to IPTp-SP and may result in more subpatent infections than the existing IPTp-SP policy. Subpatent infections were associated with increased LBW and preterm delivery. More sensitive diagnostic tests are needed to detect and treat low-grade infections.

FUNDING

Centers for Disease Control and Prevention and Worldwide Antimalarial Resistance Network.

The efficacy and safety of intermittent preventive treatment with sulphadoxine-pyrimethamine vs artemisinin-based drugs for malaria: a systematic review and meta-analysis

BACKGROUND

Malaria is one of the most serious global problems. The objective of this study is to assess whether intermittent preventive treatment (IPT) using artemisinin-based combination therapies (ACTs) was a promising alternative to IPT with sulphadoxine-pyrimethamine (IPT-SP).

METHODS

We searched the following sources up to 12 August 2020: PubMed, The Cochrane Library, Embase, Web of Science, CNKI, CBM, VIP and WanFang Database from inception. The randomized controlled trials comparing SP with ACTs for malaria were included. Data were pooled using Stata.14 software. We performed subgroup analysis based on the different types of ACTs groups and participants.

RESULTS

A total of 13 studies comprising 5180 people were included. The meta-analysis showed that ACTs had the lower risk of number of any parasitemia (RR=0.46; 95% CI 0.22 to 0.96, p=0.039; I2=90.50%, p<0.001), early treatment failure (RR=0.17; 95% CI 0.06 to 0.48, p<0.001; I2=66.60%, p=0.011) and late treatment failure (RR=0.34; 95% CI 0.13 to 0.92, p<0.001; I2=87.80%, p<0.001) compared with SP. There was no significant difference in adequate clinical response, average hemoglobin and adverse neonatal outcomes.

CONCLUSION

Combinations with ACTs appear promising as suitable alternatives for IPT-SP.

Combining malaria vaccination with chemoprevention: a promising new approach to malaria control

Malaria control has stalled in a number of African countries and novel approaches to malaria control are needed for these areas. The encouraging results of a recent trial conducted in young children in Burkina Faso and Mali in which a combination of the RTS,S/AS01E malaria vaccine and seasonal malaria chemoprevention led to a substantial reduction in clinical cases of malaria, severe malaria, and malaria deaths compared with the administration of either intervention given alone suggests that there may be other epidemiological/clinical situations in which a combination of malaria vaccination and chemoprevention could be beneficial. Some of these potential opportunities are considered in this paper. These include combining vaccination with intermittent preventive treatment of malaria in infants, with intermittent preventive treatment of malaria in pregnancy (through vaccination of women of child-bearing age before or during pregnancy), or with post-discharge malaria chemoprevention in the management of children recently admitted to hospital with severe anaemia. Other potential uses of the combination are prevention of malaria in children at particular risk from the adverse effects of clinical malaria, such as those with sickle cell disease, and during the final stages of a malaria elimination programme when vaccination could be combined with repeated rounds of mass drug administration. The combination of a pre-erythrocytic stage malaria vaccine with an effective chemopreventive regimen could make a valuable contribution to malaria control and elimination in a variety of clinical or epidemiological situations, and the potential of this approach to malaria control needs to be explored.

Towards intermittent preventive therapy in pregnancy with dihydroartemisinin-piperaquine?

Malaria is a major cause of adverse pregnancy outcomes in sub-Saharan Africa, but resistance to sulfadoxine-pyrimethamine, the only antimalarial recommended by the World Health Organisation for intermittent preventive therapy, is threatening the gains made in the last two decades. In this issue, Mlugu and colleagues present the results of a trial of dihydroartemisinin-piperaquine as an alternative to sulfadoxine-pyrimethamine. The results are impressive but raise the question why they differ so much from three previous trials.

Intermittent preventive treatment for malaria in infants

BACKGROUND

Intermittent preventive treatment could help prevent malaria in infants (IPTi) living in areas of moderate to high malaria transmission in sub-Saharan Africa. The World Health Organization (WHO) policy recommended IPTi in 2010, but its adoption in countries has been limited.

OBJECTIVES

To evaluate the effects of intermittent preventive treatment (IPT) with antimalarial drugs to prevent malaria in infants living in malaria-endemic areas.

SEARCH METHODS

We searched the following sources up to 3 December 2018: the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (the Cochrane Library), MEDLINE (PubMed), Embase (OVID), LILACS (Bireme), and reference lists of articles. We also searched the metaRegister of Controlled Trials (mRCT) and the WHO International Clinical Trials Registry Platform (ICTRP) portal for ongoing trials up to 3 December 2018.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared IPT to placebo or no intervention in infants (defined as young children aged between 1 to 12 months) in malaria-endemic areas.

DATA COLLECTION AND ANALYSIS

The primary outcome was clinical malaria (fever plus asexual parasitaemia). Two review authors independently assessed trials for inclusion, evaluated the risk of bias, and extracted data. We summarized dichotomous outcomes and count data using risk ratios (RR) and rate ratios respectively, and presented all measures with 95% confidence intervals (CIs). We extracted protective efficacy values and their 95% CIs; when an included trial did not report this data, we calculated these values from the RR or rate ratio with its 95% CI. Where appropriate, we combined data in meta-analyses and assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 12 trials that enrolled 19,098 infants; all were conducted in sub-Saharan Africa. Three trials were cluster-RCTs. IPTi with sulfadoxine-pyrimethamine (SP) was evaluated in 10 trials from 1999 to 2013 (n = 15,256). Trials evaluating ACTs included dihydroartemisinin-piperaquine (1 trial, 147 participants; year 2013), amodiaquine-artesunate (1 study, 684 participants; year 2008), and SP-artesunate (1 trial, 676 participants; year 2008). The earlier studies evaluated IPTi with SP, and were conducted in Tanzania (in 1999 and 2006), Mozambique (2004), Ghana (2004 to 2005), Gabon (2005), Kenya (2008), and Mali (2009). One trial evaluated IPTi with amodiaquine in Tanzania (2000). Later studies included three conducted in Kenya (2008), Tanzania (2008), and Uganda (2013), evaluating IPTi in multiple trial arms that included artemisinin-based combination therapy (ACT). Although the effect size varied over time and between drugs, overall IPTi impacts on the incidence of clinical malaria overall, with a 30% reduction (rate ratio 0.70, 0.62 to 0.80; 10 studies, 10,602 participants). The effect of SP appeared to attenuate over time, with trials conducted after 2009 showing little or no effect of the intervention. IPTi with SP probably resulted in fewer episodes of clinical malaria (rate ratio 0.78, 0.69 to 0.88; 8 trials, 8774 participants, moderate-certainty evidence), anaemia (rate ratio 0.82, 0.68 to 0.98; 6 trials, 7438 participants, moderate-certainty evidence), parasitaemia (rate ratio 0.66, 0.56 to 0.79; 1 trial, 1200 participants, moderate-certainty evidence), and fewer hospital admissions (rate ratio 0.85, 0.78 to 0.93; 7 trials, 7486 participants, moderate-certainty evidence). IPTi with SP probably made little or no difference to all-cause mortality (risk ratio 0.93, 0.74 to 1.15; 9 trials, 14,588 participants, moderate-certainty evidence). Since 2009, IPTi trials have evaluated ACTs and indicate impact on clinical malaria and parasitaemia. A small trial of DHAP in 2013 shows substantive effects on clinical malaria (RR 0.42, 0.33 to 0.54; 1 trial, 147 participants, moderate-certainty evidence) and parasitaemia (moderate-certainty evidence).

AUTHORS' CONCLUSIONS

In areas of sub-Saharan Africa, giving antimalarial drugs known to be effective against the malaria parasite at the time to infants as IPT probably reduces the risk of clinical malaria, anaemia, and hospital admission. Evidence from SP studies over a 19-year period shows declining efficacy, which may be due to increasing drug resistance. Combinations with ACTs appear promising as suitable alternatives for IPTi.

Healthcare provider and pregnant women's perspectives on the implementation of intermittent screening and treatment with dihydroartemisinin-piperaquine for malaria in pregnancy in western Kenya: a qualitative study

Background

In malaria endemic regions in Kenya, pregnant women are offered long-lasting insecticidal nets and intermittent preventive treatment (IPTp) with sulfadoxine–pyrimethamine (SP) at antenatal care (ANC) to prevent the adverse effects of malaria. Fears of growing SP resistance have heightened the search for alternative strategies. The implementation feasibility of intermittent screening and treatment (ISTp) with dihydroartemisinin–piperaquine (DP) in routine ANC settings was evaluated using qualitative and quantitative methods, including the exploration of healthcare provider and pregnant women’s perceptions.

Methods

Qualitative methods included data from 13 focus group discussions (FGDs) with pregnant women and 43 in-depth interviews with healthcare providers delivering ANC services. FGDs were conducted with women who had received either ISTp-DP or current policy (IPTp-SP). Thematic analysis was used to explore experiences among women and providers and findings were used to provide insights into results of the parallel quantitative study.

Results

Women were accepting of testing with rapid diagnostic tests (RDTs) and receiving treatment if malaria positive. Providers perceived DP to be an effective drug and well tolerated by women. Some providers indicated a preference for test and treat strategies to reduce unnecessary exposure to medication in pregnancy, others preferred a hybrid strategy combining screening at every ANC visit followed by IPTp-SP for women who tested negative, due to the perception that RDTs missed some infections and concerns about the growing resistance to SP. Testing with RDTs during ANC was appreciated as it was perceived to reduce wait times. The positive attitude of healthcare providers towards ISTp supports findings from the quantitative study that showed a high proportion (90%) of women were tested at ANC. There were concerns about affordability of DP and the availability of sufficient RDT stocks.

Conclusion

In ANC settings, healthcare providers and pregnant women found ISTp-DP to be an acceptable strategy for preventing malaria in pregnancy when compared with IPTp-SP. DP was considered an effective anti-malarial and a suitable alternative to IPTp-SP in the context of SP resistance. Despite providers’ lack of confidence in RDT results at current levels of sensitivity and specificity, the quantitative findings show their willingness to test women routinely at ANC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-021-03826-8.

A randomized controlled trial of dihydroartemisinin-piperaquine, artesunate-mefloquine and extended artemether-lumefantrine treatments for malaria in pregnancy on the Thailand-Myanmar border

BACKGROUND

Artemisinin and artemisinin-based combination therapy (ACT) partner drug resistance in Plasmodium falciparum have spread across the Greater Mekong Subregion compromising antimalarial treatment. The current 3-day artemether-lumefantrine regimen has been associated with high treatment failure rates in pregnant women. Although ACTs are recommended for treating Plasmodium vivax malaria, no clinical trials in pregnancy have been reported.

METHODS

Pregnant women with uncomplicated malaria on the Thailand-Myanmar border participated in an open-label randomized controlled trial comparing dihydroartemisinin-piperaquine (DP), artesunate-mefloquine (ASMQ) and a 4-day artemether-lumefantrine regimen (AL+). The primary endpoint for P. falciparum infections was the PCR-corrected cure rate and for P. vivax infections was recurrent parasitaemia, before delivery or day 63, whichever was longer, assessed by Kaplan-Meier estimate.

RESULTS

Between February 2010 and August 2016, 511 pregnant women with malaria (353 P. vivax, 142 P. falciparum, 15 co-infections, 1 Plasmodium malariae) were randomized to either DP (n=170), ASMQ (n=169) or AL+ (n=172) treatments. Successful malaria elimination efforts in the region resulted in premature termination of the trial. The majority of women had recurrent malaria (mainly P. vivax relapses, which are not prevented by these treatments). Recurrence-free proportions (95% confidence interval [95% CI]) for vivax malaria were 20.6% (5.1-43.4) for DP (n=125), 46.0% (30.9-60.0) for ASMQ (n=117) and 28.7% (10.0-50.8) for AL+ (n=126). DP and ASMQ provided longer recurrence-free intervals. PCR-corrected cure rates (95% CI) for falciparum malaria were 93.7% (81.6-97.9) for DP (n=49), 79.6% (66.1-88.1) for AMSQ (n=55) and 87.5% (74.3-94.2) for AL+ (n=50). Overall 65% (85/130) of P. falciparum infections had Pfkelch13 propeller mutations which increased over time and recrudescence occurred almost exclusively in them; risk ratio 9.42 (95% CI 1.30-68.29). Among the women with falciparum malaria, 24.0% (95% CI 16.8-33.6) had P. vivax parasitaemia within 4 months. Nausea, vomiting, dizziness and sleep disturbance were more frequent with ASMQ. Miscarriage, small-for-gestational-age and preterm birth did not differ significantly among the treatment groups, including first trimester exposures (n=46).

CONCLUSIONS

DP was well tolerated and safe, and was the only drug providing satisfactory efficacy for P. falciparum-infected pregnant woman in this area of widespread artemisinin resistance. Vivax malaria recurrences are very common and warrant chloroquine prophylaxis after antimalarial treatment in this area.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01054248 , registered on 22 January 2010.

Effect of Plasmodium berghei infection on fetuses in pregnant BALB/c mice at two periods of pregnancy

Malaria is a disease caused by a protozoan of the genus Plasmodium in humans and vertebrates. It has a high morbidity and mortality rate, especially in pregnant women living in countries with high transmission rates. Murine models have been an excellent tool to evaluate the effects of malarial infection in the mother-fetus relationship. For this reason, we evaluated the effect of malarial infection on fetal development at the beginning and middle of the gestational period in BALB/c mice infected with Plasmodium berghei ANKA. Our results show that malarial infection at the beginning of pregnancy markedly affects the development of the fetus in size, weight, and development of its limbs so that the control of the pregnant mother is relevant at the beginning of gestation

Effectiveness of Intermittent Preventive Treatment With Dihydroartemisinin-Piperaqunine Against Malaria in Pregnancy in Tanzania: A Randomized Controlled Trial

Intermittent preventive treatment in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) to prevent malaria and adverse birth outcomes is threatened by Plasmodium falciparum resistance to sulfadoxine-pyrimethamine. We investigated the effectiveness of intermittent preventive treatment in pregnancy with monthly dihydroartemisinin-piperaquine (IPTp-DHP) as an alternative option to IPTp-SP. A total of 956 malaria-free (malaria rapid diagnostic test (MRDT) negative) pregnant women from moderate malaria transmission areas in Tanzania were enrolled and randomized to receive monthly IPTp-DHP (n = 478) or IPTp-SP (n = 478) and followed for maternal and birth outcomes. The primary outcome was the prevalence of histopathologically confirmed placental malaria (active or past infection). Secondary outcomes were overall malaria at delivery, symptomatic-malaria, parasitemia during pregnancy, and adverse birth outcomes as a composite of spontaneous-abortion, premature birth, stillbirth, and low birth weight (LBW) fetal anemia. Outcome differences between treatment groups were expressed as the protective efficacy (PE), defined as 1-prevalence ratios or 1-incidence rate ratio. The prevalence of histopathologically confirmed placental malaria was significantly lower in IPTp-DHP (2.5%, 12/478) than IPTp-SP (8.2%, 39/478); PE = 69% (95% confidence interval (CI): 42-84, P < 0.001). The prevalence of maternal malaria at delivery was significantly lower in IPTp-DHP (8.2%) than IPTp-SP (18.2%, P < 0.001). The incidence per person-years at risk for symptomatic-malaria (0.02 vs. 0.12, P = 0.002) and parasitemia during pregnancy (0.28 vs. 0.67, P < 0.001) were significantly lower in the IPTp-DHP group than in the IPTp-SP group. The prevalence of any adverse birth outcomes (composite) was not significantly (P = 0.06) different between IPTp-DHP (17.9%) and IPTp-SP (23.8%). However, the prevalence of LBW (4.6% vs. 9.6%, P = 0.003) was significantly lower in IPTp-DHP compared with IPTp-SP. We report superior protective efficacy of monthly IPTp-DHP against malaria in pregnancy and LBW than IPTp-SP.

Relationships Between Measures of Malaria at Delivery and Adverse Birth Outcomes in a High-Transmission Area of Uganda

BACKGROUND

Clinical trials of interventions for preventing malaria in pregnancy often use measures of malaria at delivery as their primary outcome. Although the objective of these interventions is to improve birth outcomes, data on associations between different measures of malaria at delivery and adverse birth outcomes are limited.

METHODS

Data came from 637 Ugandan women enrolled in a randomized controlled trial of intermittent preventive treatment of malaria in pregnancy. Malaria at delivery was detected using peripheral and placental blood microscopy, placental blood loop-mediated isothermal amplification (LAMP), and placental histopathology. Multivariate analyses were used to estimate associations between measures of malaria at delivery and risks of low birth weight (LBW), small for gestational age (SGA), and preterm birth (PTB).

RESULTS

Detection of malaria parasites by microscopy or LAMP was not associated with adverse birth outcomes. Presence of malaria pigment detected by histopathology in ≥30% of high-powered fields was strongly associated with LBW (adjusted risk ratio [aRR] = 3.42, P = .02) and SGA (aRR = 4.24, P < .001) but not PTB (aRR = 0.88, P = .87).

CONCLUSIONS

A semiquantitative classification system based on histopathologically detected malaria pigment provided the best surrogate measure of adverse birth outcomes in a high-transmission setting and should be considered for use in malaria in pregnancy intervention studies.

Piperaquine Pharmacokinetics during Intermittent Preventive Treatment for Malaria in Pregnancy

Dihydroartemisinin-piperaquine (DP) is a long-acting artemisinin combination treatment that provides effective chemoprevention and has been proposed as an alternative antimalarial drug for intermittent preventive therapy in pregnancy (IPTp). Several pharmacokinetic studies have shown that dose adjustment may not be needed for the treatment of malaria in pregnancy with DP.

Dihydroartemisinin-piperaquine (DP) is a long-acting artemisinin combination treatment that provides effective chemoprevention and has been proposed as an alternative antimalarial drug for intermittent preventive therapy in pregnancy (IPTp). Several pharmacokinetic studies have shown that dose adjustment may not be needed for the treatment of malaria in pregnancy with DP. However, there are limited data on the optimal dosing for IPTp. This study aimed to evaluate the population pharmacokinetics of piperaquine given as IPTp in pregnant women. Pregnant women were enrolled in clinical trials conducted in Kenya and Indonesia and treated with standard 3-day courses of DP, administered in 4- to 8-week intervals from the second trimester until delivery. Pharmacokinetic blood samples were collected for piperaquine drug measurements before each treatment round, at the time of breakthrough symptomatic malaria, and at delivery. Piperaquine population pharmacokinetic properties were investigated using nonlinear mixed-effects modeling with a prior approach. In total, data from 366 Kenyan and 101 Indonesian women were analyzed. The pharmacokinetic properties of piperaquine were adequately described using a flexible transit absorption (n = 5) followed by a three-compartment disposition model. Gestational age did not affect the pharmacokinetic parameters of piperaquine. After three rounds of monthly IPTp, 9.45% (95% confidence interval [CI], 1.8 to 26.5%) of pregnant women had trough piperaquine concentrations below the suggested target concentration (10.3 ng/ml). Translational simulations suggest that providing the full treatment course of DP at monthly intervals provides sufficient protection to prevent malaria infection. Monthly administration of DP has the potential to offer optimal prevention of malaria during pregnancy. (This study has been registered at ClinicalTrials.gov under identifier NCT01669941 and in the ISRCTN under number ISRCTN34010937.)

Adoption of evidence-based global policies at the national level: intermittent preventive treatment for malaria in pregnancy and first trimester treatment in Kenya, Malawi, Mali and The Gambia

In 2012, the World Health Organization (WHO) updated its policy on intermittent preventive treatment in pregnancy with sulphadoxine-pyrimethamine (IPTp-SP). A global recommendation to revise the WHO policy on the treatment of malaria in the first trimester is under review. We conducted a retrospective study of the national policy adoption process for revised IPTp-SP dosing in four sub-Saharan African countries. Alongside this retrospective study, we conducted a prospective policy adoption study of treatment of first trimester malaria with artemisinin combination therapies (ACTs). A document review informed development and interpretation of stakeholder interviews. An analytical framework was used to analyse data exploring stakeholder perceptions of the policies from 47 in-depth interviews with a purposively selected range of national level stakeholders. National policy adoption processes were categorized into four stages: (1) identify policy need; (2) review the evidence; (3) consult stakeholders and (4) endorse and draft policy. Actors at each stage were identified with the roles of evidence generation; technical advice; consultative and statutory endorsement. Adoption of the revised IPTp-SP policy was perceived to be based on strong evidence, support from WHO, consensus from stakeholders; and followed these stages. Poor tolerability of quinine was highlighted as a strong reason for a potential change in treatment policy. However, the evidence on safety of ACTs in the first trimester was considered weak. For some, trust in WHO was such that the anticipated announcement on the change in policy would allay these fears. For others, local evidence would first need to be generated to support a change in treatment policy. A national policy change from quinine to ACTs for the treatment of first trimester malaria will be less straightforward than experienced with increasing the IPTp dosing regimen despite following the same policy processes. Strong leadership will be needed for consultation and consensus building at national level.

Calcium-dependent Protein Kinases in Malaria Parasite Development and Infection

Apicomplexan parasites have challenged researchers for nearly a century. A major challenge to developing efficient treatments and vaccines is the parasite's ability to change its cellular and molecular makeup to develop intracellular and extracellular niches in its hosts. Ca²⁺ signaling is an important messenger for the egress of the malaria parasite from the infected erythrocyte, gametogenesis, ookinete motility in the mosquito, and sporozoite invasion of mammalian hepatocytes. Calcium-dependent protein kinases (CDPKs) have crucial functions in calcium signaling at various stages of the parasite's life cycle; this therefore makes them attractive drug targets against malaria. Here, we summarize the functions of the various CDPK isoforms in relation to the malaria life cycle by emphasizing the molecular mechanism of developmental progression within host tissues. We also discuss the current development of anti-malarial drugs, such as how specific bumped kinase inhibitors (BKIs) for parasite CDPKs have been shown to reduce infection in Toxoplasma gondii, Cryptosporidium parvum, and Plasmodium falciparum. Our suggested combinations of BKIs, artemisinin derivatives with peroxide bridge, and inhibitors on the Ca(2+)-ATPase PfATP6 as a potential target should be inspected further as a treatment against malaria.

Drug treatment and prevention of malaria in pregnancy: a critical review of the guidelines

Background

Malaria caused by Plasmodium falciparum in pregnancy can result in adverse maternal and fetal sequelae. This review evaluated the adherence of the national guidelines drawn from World Health Organization (WHO) regions, Africa, Eastern Mediterranean, Southeast Asia, and Western Pacific, to the WHO recommendations on drug treatment and prevention of chloroquine-resistant falciparum malaria in pregnant women.

Methods

Thirty-five updated national guidelines and the President’s Malaria Initiative (PMI), available in English language, were reviewed. The primary outcome measures were the first-line anti-malarial treatment protocols adopted by national guidelines for uncomplicated and complicated falciparum malaria infections in early (first) and late (second and third) trimesters of pregnancy. The strategy of intermittent preventive treatment of malaria in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) was also addressed.

Results

This review evaluated the treatment and prevention of falciparum malaria in pregnancy in 35 national guidelines/PMI-Malaria Operational Plans (MOP) reports out of 95 malaria-endemic countries. Of the 35 national guidelines, 10 (28.6%) recommend oral quinine plus clindamycin as first-line treatment for uncomplicated malaria in the first trimester. As the first-line option, artemether–lumefantrine, an artemisinin-based combination therapy, is adopted by 26 (74.3%) of the guidelines for treating uncomplicated or complicated malaria in the second and third trimesters. Intravenous artesunate is approved by 18 (51.4%) and 31 (88.6%) guidelines for treating complicated malaria during early and late pregnancy, respectively. Of the 23 national guidelines that recommend IPTp-SP strategy, 8 (34.8%) are not explicit about directly observed therapy requirements, and three-quarters, 17 (73.9%), do not specify contra-indication of SP in human immunodeficiency virus (HIV)-infected pregnant women receiving cotrimoxazole prophylaxis. Most of the guidelines (18/23; 78.3%) state the recommended folic acid dose.

Conclusion

Several national guidelines and PMI reports require update revisions to harmonize with international guidelines and emergent trends in managing falciparum malaria in pregnancy. National guidelines and those of donor agencies should comply with those of WHO guideline recommendations although local conditions and delayed guideline updates may call for deviations from WHO evidence-based guidelines.

Evaluation of a single screen and treat strategy to detect asymptomatic malaria among pregnant women from selected health facilities in Lindi region, Tanzania

Background

In areas of high transmission, malaria in pregnancy (MiP) primarily causes asymptomatic infections; these infections nonetheless increase the risk of adverse maternal and fetal outcomes. In 2014, Tanzania initiated a single screening and treatment (SST) strategy for all pregnant women at their first antenatal care (ANC) visit using malaria rapid diagnostic tests (RDT) for surveillance purposes. However, there is paucity of data on the effectiveness of SST in the prevention of MiP. The objective of this study was to estimate the number of asymptomatic infections among pregnant women detected by SST, which would have been missed in the absence of the policy.

Methods

Data from pregnant women attending their first ANC visits between October 2017 and June 2018, including gestational age, history of fever, and RDT results, were abstracted from ANC registers in eight health centres in two randomly selected districts, Kilwa and Lindi, in Lindi Region. The proportion of symptomatic (with history of fever in the past 48 h) and asymptomatic pregnant women with positive RDTs were calculated and stratified by trimester (first, second and third). The study areas were categorized as low transmission with prevalence < 10% or moderate/high with ≥ 10%.

Results

Over the study period, 1,845 women attended their first ANC visits; 22.1% were in the first trimester (< 12 weeks gestation age). Overall 15.0% of the women had positive RDTs, and there was a trend towards higher malaria prevalence in the first (15.9%) and second (15.2%) trimesters, compared to the third (7.1%), although the differences were not statistically significant (p = 0.07). In total, 6.9% of women reported fever within the past 48 h and, of these, 96.1% were RDT positive. For every 100 pregnant women in the moderate/high and low transmission areas, SST identified 60 and 26 pregnant women, respectively, with asymptomatic infections that would have otherwise been missed. Among the 15.9% of women detected in the first trimester, 50.7% were asymptomatic.

Conclusion

In areas of moderate/high transmission, many infected women were asymptomatic, and would have been missed in the absence of SST. The benefits on maternal and fetal birth outcomes of identifying these infections depend heavily on the protection afforded by treatment, which is likely to be greatest for women presenting in the first trimester when intermittent preventive treatment (IPTp) with sulfadoxine-pyrimethamine (SP) is contraindicated, and in areas with high SP resistance, such as most parts of Tanzania. An evaluation of the impact and cost-effectiveness of SST across different transmission strata is warranted.

Intermittent screening and treatment with dihydroartemisinin-piperaquine for the prevention of malaria in pregnancy: implementation feasibility in a routine healthcare system setting in western Kenya

Background

Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended for preventing malaria in pregnancy in areas of moderate-to-high transmission in sub-Saharan Africa. However, due to increasing parasite resistance to SP, research on alternative strategies is a priority. The study assessed the implementation feasibility of intermittent screening and treatment (ISTp) in the second and third trimester at antenatal care (ANC) with malaria rapid diagnostic tests (RDTs) and treatment of positive cases with dihydroartemisinin-piperaquine (DP) compared to IPTp-SP in western Kenya.

Methods

A 10-month implementation study was conducted in 12 government health facilities in four sub-counties. Six health facilities were assigned to either ISTp-DP or IPTp-SP. Evaluation comprised of facility audits, ANC observations, and exit interviews. Intermediate and cumulative effectiveness analyses were performed on all processes involved in delivery of ISTp-DP including RDT proficiency and IPTp-SP ± directly observed therapy (DOT, standard of care). Logistic regression was used to identify predictors of receiving each intervention.

Results

A total of 388 and 389 women were recruited in the ISTp-DP and IPTp-SP arms, respectively. For ISTp-DP, 90% (289/320) of eligible women received an RDT. Of 11% (32/289) who tested positive, 71% received the correct dose of DP and 31% the first dose by DOT, and only 6% were counselled on subsequent doses. Women making a sick visit and being tested in a facility with a resident microscopist were more likely to receive ISTp-DP (AOR 1.78, 95% CI 1.31, 2.41; and AOR 3.75, 95% CI 1.31, 2.40, respectively). For IPTp-SP, only 57% received a dose of SP by DOT. Payment for a laboratory test was independently associated with receipt of SP by DOT (AOR 6.43, 95% CI 2.07, 19.98).

Conclusions

The findings indicate that the systems effectiveness of ANC clinics to deliver ISTp-DP under routine conditions was poor in comparison to IPTp-SP. Several challenges to integration of ISTp with ANC were identified that may need to be considered by countries that have introduced screening at first ANC visit and, potentially, for future adoption of ISTp with more sensitive RDTs. Understanding the effectiveness of ISTp-DP will require additional research on pregnant women’s adherence to ACT.

Associations between Malaria-Preventive Regimens and Plasmodium falciparum Drug Resistance-Mediating Polymorphisms in Ugandan Pregnant Women

Intermittent preventive treatment in pregnancy (IPTp) with monthly sulfadoxine-pyrimethamine (SP) is recommended for malaria-endemic parts of Africa, but efficacy is compromised by resistance, and, in recent trials, dihydroartemisinin-piperaquine (DP) has shown better antimalarial protective efficacy. We utilized blood samples from a recent trial to evaluate selection by IPTp with DP or SP of Plasmodium falciparum genetic polymorphisms that alter susceptibility to these drugs. The prevalence of known genetic polymorphisms associated with altered drug susceptibility was determined in parasitemic samples, including 375 collected before IPTp drugs were administered, 125 randomly selected from those receiving SP, and 80 from those receiving DP. For women receiving DP, the prevalence of mixed/mutant sequences was greater in samples collected during IPTp than that in samples collected prior to the intervention for PfMDR1 N86Y (20.3% versus 3.9%; P < 0.001), PfMDR1 Y184F (73.0% versus 53.0%; P < 0.001), and PfCRT K76T (46.4% versus 24.0%; P < 0.001). Considering SP, prior to IPTp, the prevalence of all 5 common antifolate mutations was over 92%, and this prevalence increased following exposure to SP, although none of these changes were statistically significant. For two additional mutations associated with high-level SP resistance, the prevalence of PfDHFR 164L (13.7% versus 4.0%; P = 0.004), but not PfDHPS 581G (1.9% versus 3.0%; P = 0.74), was greater in samples collected during IPTp compared to those collected before the intervention. Use of IPTp in Uganda selected for parasites with mutations associated with decreased susceptibility to IPTp regimens. Thus, a potential drawback of IPTp is selection of parasites with decreased drug susceptibility.