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Background: Malaria in early pregnancy occurs at a time when the placenta is developing, with possible consequences for placental function and fetal growth. We assessed the association between first trimester malaria and fetal growth documented through repeated ultrasound scans., Methods: The RECIPAL preconceptional cohort included 411 Beninese pregnant women followed from 7 weeks' gestation (wg) until delivery. Among them, 218 had 4 scans for fetal monitoring at 16, 22, 28, and 34 wg. Multivariate seemingly unrelated regression models were used to assess association of microscopic malaria in the first trimester (<15 wg) with abdominal circumference, head circumference, biparietal diameter, and femur length throughout pregnancy., Results: Of 39% (86/218) of women with at least 1 microscopic malarial infection during pregnancy, 52.3% (45/86) were infected in the first trimester. Most women (88.5%) were multiparous. There was no association between adjusted z-scores for fetal growth parameters and first trimester malaria. Parity, newborn sex, socioeconomic level, and maternal body mass index significantly influenced fetal growth., Conclusions: In a context where malaria infections in pregnancy are well detected and treated, their adverse effect on fetal growth may be limited. Our results argue in favor of preventing and treating infections as early as the first trimester., (© The Author(s) 2022. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Harmful maternal and neonatal health outcomes result from malaria in pregnancy, the prevention of which primarily relies on intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP). The World Health Organization recommends IPTp-SP in sub-Saharan Africa, but implementation is highly heterogeneous and often suboptimal in terms of the number of doses and their timing. In this study, we assessed the impact of this heterogeneity on malaria in pregnancy, mainly with respect to submicroscopic Plasmodium falciparum infections., Methods: We used data from 273 Beninese women followed throughout pregnancy. Screening for P. falciparum infections, using both microscopy-based and polymerase chain reaction (PCR)-based methods, was performed monthly, and information on IPTp-SP doses was collected. Gestational age was estimated by repeated ultrasound scans. Using a negative binomial model, we investigated the effect of IPTp-SP doses and timing after 17 weeks of gestation on the number of P. falciparum infections, focusing on submicroscopic infections detectable only by PCR., Results: At least 2 IPTp-SP doses were taken by 77.3% of the women. The median gestational age at the first IPTp-SP dose was 22 weeks. A late first IPTp-SP dose (>21.2 weeks) was marginally associated with an increased number of P. falciparum infections (adjusted incidence rate ratio [aIRR] = 1.3; P = .098). The number of IPTp-SP doses was not associated with the number of submicroscopic infections (aIRR = 1.2, P = .543)., Conclusions: A late first IPTp-SP dose failed to provide optimal protection against P. falciparum, especially submicroscopic infections. This highlights the need for a new antimalarial drug for IPTp that could be taken early in pregnancy., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: Malaria infections in the first trimester of pregnancy are frequent and deleterious for both mother and child health. To investigate if these early infections are newly acquired or already present in the host, we assessed whether parasites detected before pregnancy and those detected in early pregnancy are the same infection., Methods: We used data from the preconceptional "RECIPAL" study (Benin, 2014-2017). Sixty-three pregnant women of 411 included who had a malaria infection detected by quantitative polymerase chain reaction both before pregnancy and at the first antenatal care (ANC) visit were selected for this study. Two highly polymorphic markers, msp-2 and glurp, and a fragment-analysis method were used to enumerate the Plasmodium falciparum genotypes and to quantify their proportions within isolates. An infection was considered as persistent when identical msp-2 and glurp genotypes were found in the corresponding prepregnancy and early-pregnancy samples., Results: The median time between the 2 malaria screenings was 3 months. The median gestational age at the first ANC visit was 6.4 weeks. Most infections before pregnancy were submicroscopic infections. Based on both msp-2 and glurp genotyping, the infection was similar before and in early pregnancy in 46% (29/63) of cases., Conclusions: Almost half of P. falciparum infections detected in the first trimester originate before pregnancy. Protecting young women from malaria infection before pregnancy might reduce the prevalence of malaria in early pregnancy and its related poor maternal and birth outcomes., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: In the context of global malaria elimination efforts, special attention is being paid to submicroscopic Plasmodium falciparum infections. In pregnant, sub-Saharan African women, such infections are more prevalent than microscopic infections, and are thought to have adverse effects on both mothers' and newborns' health. However, no study has studied the dynamics and determinants of these infections throughout pregnancy. Retard de Croissance Intra-uterin et Paludisme (RECIPAL), a preconception cohort study carried out in Benin between 2014 and 2017, represented a unique opportunity to assess this issue., Methods: We used data from 273 pregnant Beninese women who were followed-up from preconception to delivery. We studied the dynamics of and factors influencing submicroscopic (and microscopic) P. falciparum infections during the 3 trimesters of pregnancy, using an ordinal logistic mixed model., Results: The incidence rate of submicroscopic P. falciparum infections during pregnancy was 12.7 per 100 person-months (95% confidence interval [CI] 10.8-14.9), compared to 6.7 per 100 person-months (95% CI 5.5-8.1) for microscopic infections. The prevalences were highest in the first trimester for both submicroscopic and microscopic infections. After adjustment for potential confounding factors, we found that those of young age and those with a submicroscopic P. falciparum infection prior to pregnancy were at significantly higher risks of submicroscopic and microscopic infections throughout pregnancy, with a more pronounced effect in the first trimester of pregnancy., Conclusions: The first trimester of pregnancy is a particularly high-risk period for P. falciparum infection during pregnancy, especially for the youngest women. Malaria prevention tools covering the preconception period and early pregnancy are urgently needed to better protect pregnant women and their newborns., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: In sub-Saharan Africa, malaria in the first half of pregnancy is harmful for both the mother and her fetus. However, malaria in the first trimester of pregnancy, when women are usually not protected against malaria, has been little investigated. For the first time, we assessed the effects of malaria in the first trimester on maternal and birth outcomes using a preconceptional study design., Methods: From June 2014 to March 2017, 1214 women of reproductive age were recruited and followed monthly until 411 became pregnant. The pregnant women were then followed from 5-6 weeks of gestation until delivery. Path analysis was used to assess the direct effect (ie, not mediated by malaria in the second or third trimester) of malaria in the first trimester on maternal anemia and poor birth outcomes. The cumulative effect of infections during pregnancy on the same outcomes was also evaluated., Results: The prevalence of malaria infections in the first trimester was 21.8%. Malaria in the first trimester was significantly associated with maternal anemia in the third trimester (adjusted odds ratio 2.25, 95% confidence interval 1.11-4.55). While we did not find evidence of any direct effect of first trimester malaria infections on birth outcomes, their association with infections later in pregnancy tended to increase the risk of low birth weights., Conclusions: Malaria infections in the first trimester were highly prevalent and have deleterious effects on maternal anemia. They highlight the need for additional preventive measures, starting in early pregnancy or even before conception., (© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: According to the Developmental Origins of Health and Diseases paradigm, the fetal period is highly vulnerable and may have profound effects on later health. Few studies assessed the effect of small-for-gestational age (SGA), a proxy for fetal growth impairment, on risk of malaria during infancy in Africa., Methods: We used data from a cohort of 398 mother-child pairs, followed from early pregnancy to age 1 year in Benin. Malaria was actively and passively screened using thick blood smear. We assessed the effect of SGA on risk of malaria infection and clinical malaria from birth to 12 months, after stratifying on the infant's age using a logistic mixed regression model., Results: After adjustment for potential confounding factors and infant's exposure to mosquitoes, SGA was associated with a 2-times higher risk of malaria infection (adjusted odds ratio [aOR] = 2.16; 95% confidence interval [CI], 1.04-4.51; P = .039) and clinical malaria (aOR = 2.33; 95% CI, 1.09-4.98; P = .030) after age 6 months., Conclusion: Results suggest higher risk of malaria during the second semester of life in SGA infants, and argue for better follow-up of these infants after birth, as currently for preterm babies., (© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: There is a lack of data on the burden of malaria in the first trimester of pregnancy in Africa, mainly because pregnant women generally attend the maternity clinic late. Bed nets are rarely provided to women before the second trimester of pregnancy and intermittent preventive treatment with sulfadoxine-pyrimethamine is not recommended before the second trimester, leaving women insufficiently or not protected in early pregnancy., Methods: To assess the burden of first trimester malaria, 387 women were followed up monthly from preconception to delivery. They were screened for malaria monthly from early pregnancy until delivery. A logistic multilevel model was used to assess maternal factors associated with malaria during the first trimester., Results: The proportion of women with at least 1 microscopic malaria infection during the first trimester of pregnancy was 20.8%. Women infected with malaria preconception were more likely to be infected during the first trimester (adjusted odds ratio: 2.68; 95% confidence interval, 1.24-5.78). Early gestational age was also positively correlated with malaria infection., Conclusions: Using a preconceptional study design, we showed that malaria was highly prevalent in early pregnancy. This calls for the assessment of new strategies that could protect women as soon as the first trimester.

Background: Few studies have evaluated the effect of malaria on intrauterine growth restriction on the basis of the fetal growth rate, rather than just the small-for-gestational age z score. Here, we assessed the impact of malaria on IUGR, using data from a longitudinal, ultrasonography-based follow-up study of Beninese women., Methods: A total of 1016 women were followed up from gestational week 17 to delivery. Malaria was detected every month. Women underwent ultrasonography 4 times for gestational age determination and fetal biometry. We assessed the effect of malaria on birth weight-for-gestational age z score (n = 735 women) and fetal growth velocity (n = 664), defined as a change in fetal weight z score over time., Results: Malaria was detected in 43% of women. Fetal growth velocity was negative overall, decreasing further at the end of the third trimester. Women with ≥2 malarial parasite infections tended to have lower z scores than uninfected women. Malaria both in early and late pregnancy was associated with a reduction in fetal growth velocity, which occurred either immediately or with a delay after infection., Discussions: We confirmed the deleterious effect of malaria during both early and late pregnancy on fetal growth. This stresses the importance of starting preventive measures against malaria as early as possible during pregnancy., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

According to the current World Health Organization guidelines, the drug prevention of malaria during pregnancy does not adequately cover the first trimester of gestation in high-transmission areas. Although the pathophysiological mechanisms of early infections are not completely understood yet, a review of the most recent studies on the topic suggests that their consequences are serious in terms of maternal anemia and low birth weight. Consequently, there is a need to focus on the awareness of women in a period hard to access, to develop safe drugs to be used in the first trimester, and to consider preconceptional interventions in teenage girls, such as a new malaria vaccine to be used in pregnancy., (© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: In the context of the increasing resistance to sulfadoxine-pyrimethamine (SP), we evaluated the efficacy of mefloquine (MQ) for intermittent preventive treatment during pregnancy (IPTp)., Methods: A multicenter, open-label equivalence trial was conducted in Benin from July 2005 through April 2008. Women of all gravidities were randomized to receive SP (1500 mg of sulfadoxine and 75 mg of pyrimethamine) or 15 mg/kg MQ in a single intake twice during pregnancy. The primary end point was the proportion of low-birth-weight (LBW) infants (body weight, <2500 g; equivalence margin, 5%)., Results: A total of 1601 women were randomized to receive MQ (n=802)or SP (n=799).In the modified intention-to-treat analysis, which assessed only live singleton births, 59 (8%) of 735 women who were given MQ and 72 (9.8%) of 730 women who were given SP gave birth to LBW infants (difference between low birth weights in treatment groups, -1.8%; 95% confidence interval [CI], -4.8% to 1.1%]), establishing equivalence between the drugs. The per-protocol analysis showed consistent results. MQ was more efficacious than SP in preventing placental malaria (prevalence, 1.7% vs 4.4% of women; P = .005),clinical malaria (incidence rate, 26 cases/10,000 person-months vs. 68 cases/10,000 person-months; P = .007) and maternal anemia at delivery (as defined by a hemoglobin level <10 g/dL) (prevalence, 16% vs 20%; marginally significant at P = .09). Adverse events (mainly vomiting, dizziness, tiredness, and nausea) were more commonly associated with the use of MQ (prevalence, 78% vs 32%; P < 10(-3)) One woman in the MQ group had severe neuropsychiatric symptoms., Conclusions: MQ proved to be highly efficacious--both clinically and parasitologically--for use as IPTp. However, its low tolerability might impair its effectiveness and requires further investigations.

Background: In West Africa, treatment for the prevention of malaria during pregnancy has recently changed from chloroquine (CQ) prophylaxis to intermittent preventive treatment (IPTp). We assessed the benefits of IPTp with respect to those of CQ, using a before-after study., Methods: CQ efficacy was evaluated during a cross-sectional survey conducted in Benin between April 2004 and April 2005. IPTp efficacy was assessed using data from an ongoing clinical trial to compare sulfadoxine-pyrimethamine with mefloquine that began in the same maternity clinics during July 2005; the present analysis is limited to women who delivered between November 2005 and November 2006. Treatment assignments were not unblinded. We compared the efficacy of the 2 strategies against low birth weight and placental infection by performing multiple logistic regressions., Results: A total of 1699 women (1090 in the CQ group and 609 in the IPTp group) who delivered live singletons were analyzed. Characteristics of women in the CQ group were similar to those of women in the IPTp group. We showed that women in the IPTp group had a significantly decreased risk of delivering an infant with a low birth weight (adjusted odds ratio [aOR], 0.54; 95% confidence interval [CI], 0.38-0.78) and placental infection (aOR, 0.15; 95% CI, 0.09-0.24)., Conclusion: We clearly evidenced that IPTp is substantially more beneficial than CQ for the prevention of malaria during pregnancy.

Background: Controversy exists about the management of patients with imported Plasmodium falciparum malaria. We postulated that rapid parasite clearance supports ambulatory care, or, conversely, that factors associated with longer parasite clearance time (PCT) could be used as hospitalization criteria., Methods: Hospitalized patients with imported falciparum malaria recruited through one single travel clinic between 1993 and 2000. We used a linear regression to identify factors independently associated with PCT defined as the time in hours from antimalarial drug administration until the first negative malaria smear., Results: Among 400 patients hospitalized with falciparum malaria, mean (range) PCT was 58 (1-189) hours. In multivariate analysis, severe malaria, gastrointestinal signs, initial temperature greater than or equal to 40 degrees C, parasitemia greater than or equal to 1%, and platelet counts less than 50,000/microL were associated with longer PCT. Offering ambulatory care to patients aged 15 to 64 years with none of the factors associated with longer PCT in the study would have resulted in 147 (37%) patients receiving outpatient care., Conclusion: Factors identified in this model may help physicians determine which P falciparum malaria patients can be treated on an ambulatory basis, and contribute to revisions of national guidelines for imported malaria management.

Background: Diarrhea is the most common illness associated with international tourism. We evaluated the efficacy of a probiotic preparation of nonviable Lactobacillus acidophilus (hereafter referred to as LA) for the prevention of traveler's diarrhea., Methods: We conducted a randomized, double-blind, controlled trial. Travelers were randomized to receive either LA or placebo twice daily from 1 day before their departure to 3 days after their return. On each day of the trip and the week following the return, travelers had to record the number and consistency of stools and their adherence to the treatment. Diarrhea was defined as > or =3 unformed stools in a 24-h period., Results: From January 2001 to September 2004, a total of 174 subjects were randomized to each treatment group. Half of the travelers went to West Africa, and organized tours or backpacking were the most common modes of traveling. The incidence of diarrhea did not differ between the 2 groups; it was 61.4 cases per 100 person-months in the LA group (95% confidence interval [CI], 44.1-85.5) and 43.4 cases per 100 person-months in the placebo group (95% CI, 30.0-62.9) (P=.14). Adjustment for travel duration and other variables did not reveal any difference between the 2 groups (adjusted hazard ratios comparing the LA and placebo groups were 1.43 [95% CI, 0.87-2.36] in an intent-to-treat analysis and 1.38 [95% CI, 0.79-2.39] in an efficacy analysis)., Conclusions: There was no beneficial effect of treatment with LA for the prevention of travelers' diarrhea. More studies are required to assess the efficacy of other specific probiotics (e.g., a Lactobacillus rhamnosus GG preparation) for preventing traveler's diarrhea.