Comparison of real-time PCR and microscopy for malaria parasite detection in Malawian pregnant women

Abstract Background New diagnostic tools for malaria are required owing to the changing epidemiology of malaria, particularly among pregnant women in sub-Saharan Africa. Real-time PCR assays targeting Plasmodium falciparum lactate dehydrogenase (pfldh) gene may facilitate the identification of a high proportion of pregnant women with a P. falciparum parasitaemia below the threshold of microscopy. These molecular methods will enable further studies on the effects of these submicroscopic infections on maternal health and birth outcomes. Methods The pfldh real-time PCR assay and conventional microscopy were compared for the detection of P. falciparum from dried blood spots and blood smears collected from the peripheral blood of 475 Malawian women at delivery. A cycle threshold (Ct) of the real-time PCR was determined optimizing the sensitivity and specificity of the pfldh PCR assay compared to microscopy. A real-time PCR species-specific assay was applied to identify the contribution to malaria infections of three Plasmodium species (P. falciparum P. ovale and P. malariae) in 44 discordant smear and pfldh PCR assay results. Results Of the 475 women, P. falciparum was detected in 11 (2.3%) by microscopy and in 51 (10.7%) by real-time PCR; compared to microscopy, the sensitivity of real-time PCR was 90.9% and the specificity 91.2%. If a Ct value of 38 was used as a cut-off, specificity improved to 94.6% with no change in sensitivity. The real-time PCR species-specific assay detected P. falciparum alone in all but four samples: two samples were mixed infections with P. falciparum and P. malariae, one was a pure P. malariae infection and one was a pfldh PCR assay-positive/species-specific assay-negative sample. Of three P. malariae infections detected by microscopy, only one was confirmed by the species-specific assay. Conclusions Although microscopy remains the most appropriate method for clinical malaria diagnosis in field settings, molecular diagnostics such as real-time PCR offer a more reliable means to detect malaria parasites, particularly at low levels. Determination of the possible contribution of these submicroscopic infections to poor birth outcomes and maternal health is critical. For future studies to investigate these effects, this pfldh real-time PCR assay offers a reliable detection method

Antibody to P. falciparum in Pregnancy Varies with Intermittent Preventive Treatment Regime and Bed Net Use

Antibodies towards placental-binding P. falciparum are thought to protect against pregnancy malaria; however, environmental factors may affect antibody development.Using plasma from pregnant Malawian women, we measured IgG against placental-binding P. falciparum parasites by flow cytometry, and related results to intermittent preventive treatment (IPTp) regime, and bed net use. Bed net use was associated with decreased antibody levels at mid-pregnancy but not at 1 month post partum (1 mpp). At 1 mpp a more intensive IPTp regime was associated with decreased antibody levels in primigravidae, but not multigravidae.Results suggest bed nets and IPTp regime influence acquisition of pregnancy-specific P. falciparum immunity

Risk factors for impaired maternal bonding when infants are 3 months old: a longitudinal population based study from Japan

BackgroundImpaired maternal bonding has been associated with antenatal and postnatal factors, especially postpartum depression. Only a few population-based, longitudinal studies have examined the association between maternal depression and bonding in outside western countries. In addition, little is known about the association between psychosocial factors during pregnancy and impaired maternal bonding. The aim of this study was to investigate risk factors associated with impaired maternal bonding 3 months after delivery using Japanese population-based, longitudinal study from pregnancy period to 3 months after delivery.MethodsThis study was performed at the public health care center in Hekinan city, Aichi prefecture, Japan. Mothers who participated the infant's health check-up 3 months after delivery from July 2013 to Jun 2015 completed the Postpartum Bonding Questionnaire (PBQ) and the Edinburgh Postnatal Depression Scale (EPDS) 1 month after delivery. Information was also provided from home visit at 1 month after delivery, birth registration form, and pregnancy notification form. The study included 1060 mothers with a mean age of 29.90years, who had given birth at a mean of 38.95weeks.ResultsBivariate and multivariate logistic regression analyses were conducted to identify the association between antenatal and postnatal factors and impaired maternal bonding. The main findings were that maternal negative feelings about pregnancy (OR=2.16, 95% CI=1.02-4.56) and postpartum depression at 1 month after delivery (OR=7.85, 95% CI=3.44-17.90) were associated with higher levels of impaired maternal bonding 1 months after delivery. Mothers who had delivered their first child had increased odds of a moderate level of impaired maternal bonding 3 months after delivery (OR=1.85, 95% CI=1.22-2.81).ConclusionsThe findings emphasize the importance of identifying mothers with depression and those with maternal negative feelings towards pregnancy to assess possible impaired maternal bonding

Increased prevalence of dhfr and dhps mutants at delivery in Malawian pregnant women receiving intermittent preventive treatment for malaria

In the context of an Intermittent preventive treatment (IPTp) trial for pregnant women in Malawi, P. falci-parum samples from 85 women at enrollment and 35 women at delivery were genotyped for mutations associated with sulfadoxine-pyrimethamine resistance. The prevalence of the highly resistant haplotype with mutations at codons 51 and 108 of dihydrofolate reductase (dhfr) and codons 437 and 540 of dihydropteroate synthase (dhps) increased from 81% at enrollment to 100% at delivery (p=0.01). Pregnant women who were smear-positive at enrollment were more likely to have P. falciparum parasitemia at delivery. These results lend support to concerns that IPTp use may lead to increased drug resistance in pregnant women during pregnancy and emphasize the importance of screening pregnant women for malaria parasites in areas with prevalent SP resistance even when they are already on IPTp

The effect of monthly sulfadoxine-pyrimethamine, alone or with azithromycin, on pcr-diagnosed malaria at delivery: A randomized controlled trial

10.1371/journal.pone.0041123PLoS ONE77

Contrasting levels of β‐diversity and underlying phylogenetic trends indicate different paths to chemical diversity in highland and lowland willow species

Diverse specialised metabolites contributed to the success of vascular plants in colonising most terrestrial habitats. Understanding how distinct aspects of chemical diversity arise through heterogeneous environmental pressures can help us understand the effects of abiotic and biotic stress on plant evolution and community assembly. We examined highland and lowland willow species within a phylogenetic framework to test for trends in their chemical α-diversity (richness) and β-diversity (variation among species sympatric in elevation). We show that differences in chemistry among willows growing at different elevations occur mainly through shifts in chemical β-diversity and due to convergence or divergence among species sharing their elevation level. We also detect contrasting phylogenetic trends in concentration and α-diversity of metabolites in highland and lowland willow species. The resulting elevational patterns contribute to the chemical diversity of willows and suggest that variable selective pressure across ecological gradients may, more generally, underpin complex changes in plant chemistry

Internet-assisted cognitive behavioural therapy with telephone coaching for anxious Finnish children aged 10-13 years: study protocol for a randomised controlled trial

AbstractIntroductionChildhood anxiety is common, causes significant functional impairment and may lead to psychosocial problems by adulthood. Although cognitive behavioural therapy (CBT) is effective for treating anxiety, its availability is limited by the lack of trained CBT therapists and easily accessible local services. To address the challenges in both recognition and treatment, this study combines systematic anxiety screening in the general population with a randomised controlled trial (RCT) on internet-assisted CBT (ICBT) with telephone coaching. Child, family and intervention-related factors are studied as possible predictors or moderators, together with the COVID-19 pandemic.Methods and analysisThe study is an open two-parallel group RCT, stratified by sex, that compares ICBT with telephone coaching to an education control. Children aged 10–13 are screened at yearly school healthcare check-ups using five items from the Screen for Child Anxiety Related Disorders (SCARED) Questionnaire. The families of children who screen positive for anxiety are contacted to assess the family’s eligibility for the RCT. The inclusion criteria include scoring at least 22 points in the 41-item SCARED Questionnaire. The primary outcome is the SCARED child and parent reports. The secondary outcomes include the impact of anxiety, quality of life, comorbidity, peer relationships, perceptions of school, parental well-being and service use. Additional measures include demographics and life events, anxiety disorder diagnoses, as well as therapeutic partnerships, the use of the programme and general satisfaction among the intervention group.Ethics and disseminationThe study has been approved by the research ethics board of the Hospital District of South West Finland and local authorities. Participation is voluntary and based on informed consent. The anonymity of the participants will be protected and the results will be published in a scientific journal and disseminated to healthcare professionals and the general public.Trial registration number ClinicalTrials.gov NCT03310489, pre-results, initially released on 30 September 2017.</p

Combination of probenecid-sulphadoxine-pyrimethamine for intermittent preventive treatment in pregnancy

The antifolate sulphadoxine-pyrimethamine (SP) has been used in the intermittent prevention of malaria in pregnancy (IPTp). SP is an ideal choice for IPTp, however, as resistance of Plasmodium falciparum to SP increases, data are accumulating that SP may no longer provide benefit in areas of high-level resistance. Probenecid was initially used as an adjunctive therapy to increase the blood concentration of penicillin; it has since been used to augment concentrations of other drugs, including antifolates. The addition of probenecid has been shown to increase the treatment efficacy of SP against malaria, suggesting that the combination of probenecid plus SP may prolong the useful lifespan of SP as an effective agent for IPTp. Here, the literature on the pharmacokinetics, adverse reactions, interactions and available data on the use of these drugs in pregnancy is reviewed, and the possible utility of an SP-probenecid combination is discussed. This article concludes by calling for further research into this potentially useful combination

Trials

BACKGROUND: The aim of this open-label, randomized controlled trial conducted in four African countries (Madagascar, Niger, Central African Republic, and Senegal) is to compare three strategies of renutrition for moderate acute malnutrition (MAM) in children based on modulation of the gut microbiota with enriched flours alone, enriched flours with prebiotics or enriched flours coupled with antibiotic treatment. METHODS: To be included, children aged between 6 months and 2 years are preselected based on mid-upper-arm circumference (MUAC) and are included based on a weight-for-height Z-score (WHZ) between - 3 and - 2 standard deviations (SD). As per current protocols, children receive renutrition treatment for 12 weeks and are assessed weekly to determine improvement. The primary endpoint is recovery, defined by a WHZ >/= - 1.5 SD after 12 weeks of treatment. Data collected include clinical and socioeconomic characteristics, side effects, compliance and tolerance to interventions. Metagenomic analysis of gut microbiota is conducted at inclusion, 3 months, and 6 months. The cognitive development of children is evaluated in Senegal using only the Developmental Milestones Checklist II (DMC II) questionnaire at inclusion and at 3, 6, and 9 months. The data will be correlated with renutrition efficacy and metagenomic data. DISCUSSION: This study will provide new insights for the treatment of MAM, as well as original data on the modulation of gut microbiota during the renutrition process to support (or not) the microbiota hypothesis of malnutrition. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT03474276 Last update 28 May 2018