Reflections on Participation in a Trial on Hydroxychloroquine as Prevention for COVID-19 among Health Workers in Niger.

In 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a rapidly emerging virus causing the coronavirus disease 2019 (COVID-19) pandemic, had no known effective prophylaxis and no widely available proven effective antiviral treatment. Hydroxychloroquine/Chloroquine was identified as an early potential therapeutic candidate drawing on evidence from reports of both in vitro and in vivo testing. A multicountry placebo-controlled randomized trial was set to evaluate the use of hydroxychloroquine/chloroquine to prevent infection in healthcare workers and staff working in a health facility involved in COVID-19 management. One of the sites of this trial was in Niger. In Niger, of the 240 persons who were provided information about the study and with whom participation was discussed, only five participants provided their informed consent. In this article, we describe the key difficulties encountered in the conduct of this trial from the perspective of the site study team. Among the difficulties, we recognize that the epidemic context, controversy surrounding hydroxychloroquine, vaccine rollout, participants' perspectives, and trial design had a major impact on participation.

Practices and challenges related to antibiotic use in paediatric treatment in hospitals and health centres in Niger and Uganda: a mixed methods study.

BACKGROUND: Antibiotic resistance is a significant public health problem and is responsible for high mortality in children and new-borns. Strengthening the rational use of antibiotics and improving the quality and access to existing antibiotics are important factors in the fight against antibiotic resistance. This study aims to provide knowledge on the use of antibiotics in children in resource-limited countries in order to identify problems and possible avenues for improvement of antibiotics use. METHODS: We conducted a retrospective study in July 2020 and collected quantitative clinical and therapeutic data on antibiotic prescriptions between January and December 2019 in 4 hospitals or health centres in both Uganda and Niger, respectively from January to December 2019. Semi-structured interviews and focus groups were conducted among healthcare personnel and carers for children under 17 years of age, respectively. RESULTS: A total of 1,622 children in Uganda and 660 children in Niger (mean age of 3.9 years (SD 4.43)) who received at least one antibiotic were included in the study. In hospital settings, 98.4 to 100% of children prescribed at least one antibiotic received at least one injectable antibiotic. Most hospitalized children received more than one antibiotic in both Uganda (52.1%) and Niger (71.1%). According to the WHO-AWaRe index, the proportion of prescriptions of antibiotics belonging to the Watch category was 21.8% (432/1982) in Uganda and 32.0% (371/1158) in Niger. No antibiotics from the Reserve category were prescribed. Health care provider's prescribing practices are rarely guided by microbiological analyses. Prescribers are faced with numerous constraints, such as lack of standard national guidelines, unavailability of essential antibiotics at the level of hospital pharmacies, the limited financial means of the families, and pressure to prescribe antibiotics from caregivers as well as from drug company representatives. The quality of some antibiotics provided by the National Medical Stores to the public and private hospitals has been questioned by some health professionals. Self-medication is a widespread practice for the antibiotic treatment of children for economic and access reasons. CONCLUSION: The study findings indicate that an intersection of policy, institutional norms and practices including individual caregiver or health provider factors, influence antibiotic prescription, administration and dispensing practices.

Faecal carriage of extended-spectrum ß-lactamase-producing Escherichia coli in a remote region of Niger.

OBJECTIVE: Whole genome sequencing (WGS) of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-E. coli) in developing countries is lacking. Here we describe the population structure and molecular characteristics of ESBL-E. coli faecal isolates in rural Southern Niger. METHODS: Stools of 383 healthy participants were collected among which 92.4% were ESBL-Enterobacterales carriers. A subset of 90 ESBL-E. coli containing stools (109 ESBL-E. coli isolates) were further analysed by WGS, using short- and long-reads. RESULTS: Most isolates belonged to the commensalism-adapted phylogroup A (83.5%), with high clonal diversity. The blaCTX-M-15 gene was the major ESBL determinant (98.1%), chromosome-integrated in approximately 50% of cases, in multiple integration sites. When plasmid-borne, blaCTX-M-15 was found in IncF (57.4%) and IncY plasmids (26.2%). Closely related plasmids were found in different genetic backgrounds. Genomic environment analysis of blaCTX-M-15 in closely related strains argued for mobilisation between plasmids or from plasmid to chromosome. CONCLUSIONS: Massive prevalence of community faecal carriage of CTX-M-15-producing E. coli was observed in a rural region of Niger due to the spread of highly diverse A phylogroup commensalism-adapted clones, with frequent chromosomal integration of blaCTX-M-15. Plasmid spread was also observed. These data suggest a risk of sustainable implementation of ESBL in community faecal carriage.

Impact and cost-effectiveness of rotavirus vaccination in Niger: a modelling study evaluating alternative rotavirus vaccines.

OBJECTIVES: To evaluate the cost-effectiveness of alternative rotavirus vaccines in Niger, using UNIVAC, a proportionate outcomes model. SETTING: The study leverages global, regional and local data to inform cost-effectiveness modelling. Local data were collected as part of a clinical trial taking place in the Madarounfa district, Maradi region, Niger. PARTICIPANTS: The study models impact of infants vaccination on rotavirus gastroenteritis in children under 5 years of age. INTERVENTIONS: We compared the use of ROTARIX (GlaxoSmithKline, Belgium), ROTAVAC (Bharat Biotech, India) and ROTASIIL (Serum Institute, India) to no vaccination and to each other over a 10-year period starting in 2021. RESULTS: We estimated that ROTARIX, ROTAVAC and ROTASIIL would each prevent 13 million cases and 20 000 deaths of children under 5 years over a 10-year period in Niger. Compared with no vaccination, the cost to avert a disability-adjusted life-year was US$146 with ROTARIX, US$107 with ROTASIIL and US$76 with ROTAVAC from the government perspective. ROTAVAC dominated ROTARIX and ROTASIIL (eg, provided similar or higher benefits at a lower cost) and had 90% chance to be cost-effective at a US$100 willingness-to-pay threshold. CONCLUSIONS: This study can inform decision-making around rotavirus vaccination policy in Niger, demonstrating that ROTAVAC is likely the most cost-effective option. Alternative products (ROTASIIL and ROTARIX) may also be considered by decision-makers if they are priced more competitively, or if their cold chain requirements could bring additional economic benefits.

Evaluation of multiple micronutrient supplementation and medium-quantity lipid-based nutrient supplementation in pregnancy on child development in rural Niger: A secondary analysis of a cluster randomized controlled trial.

BACKGROUND: It is estimated that over 250 million children under 5 years of age in low- and middle-income countries (LMICs) do not reach their full developmental potential. Poor maternal diet, anemia, and micronutrient deficiencies during pregnancy are associated with suboptimal neurodevelopmental outcomes in children. However, the effect of prenatal macronutrient and micronutrient supplementation on child development in LMIC settings remains unclear due to limited evidence from randomized trials. METHODS AND FINDINGS: We conducted a 3-arm cluster-randomized trial (n = 53 clusters) that evaluated the efficacy of (1) prenatal multiple micronutrient supplementation (MMS; n = 18 clusters) and (2) lipid-based nutrient supplementation (LNS; n = 18 clusters) as compared to (3) routine iron-folic acid (IFA) supplementation (n = 17 clusters) among pregnant women in the rural district of Madarounfa, Niger, from March 2015 to August 2019 (ClinicalTrials.gov identifier NCT02145000). Children were followed until 2 years of age, and the Bayley Scales of Infant and Toddler Development III (BSID-III) were administered to children every 3 months from 6 to 24 months of age. Maternal report of WHO gross motor milestone achievement was assessed monthly from 3 to 24 months of age. An intention-to-treat analysis was followed. Child BSID-III data were available for 559, 492, and 581 singleton children in the MMS, LNS, and IFA groups, respectively. Child WHO motor milestone data were available for 691, 781, and 753 singleton children in the MMS, LNS, and IFA groups, respectively. Prenatal MMS had no effect on child BSID-III cognitive (standardized mean difference [SMD]: 0.21; 95% CI: -0.20, 0.62; p = 0.32), language (SMD: 0.16; 95% CI: -0.30, 0.61; p = 0.50) or motor scores (SMD: 0.18; 95% CI: -0.39, 0.74; p = 0.54) or on time to achievement of the WHO gross motor milestones as compared to IFA. Prenatal LNS had no effect on child BSID-III cognitive (SMD: 0.17; 95% CI: -0.15, 0.49; p = 0.29), language (SMD: 0.11; 95% CI: -0.22, 0.44; p = 0.53) or motor scores (SMD: -0.04; 95% CI: -0.46, 0.37; p = 0.85) at the 24-month endline visit as compared to IFA. However, the trajectory of BSID-III cognitive scores during the first 2 years of life differed between the groups with children in the LNS group having higher cognitive scores at 18 and 21 months (approximately 0.35 SD) as compared to the IFA group (p-value for difference in trajectory <0.001). Children whose mothers received LNS also had earlier achievement of sitting alone (hazard ratio [HR]: 1.57; 95% CI: 1.10 to 2.24; p = 0.01) and walking alone (1.52; 95% CI: 1.14 to 2.03; p = 0.004) as compared to IFA, but there was no effect on time to achievement of other motor milestones. A limitation of our study is that we assessed child development up to 2 years of age, and, therefore, we may have not captured effects that are easier to detect or emerge at older ages. CONCLUSIONS: There was no benefit of prenatal MMS on child development outcomes up to 2 years of age as compared to IFA. There was evidence of an apparent positive effect of prenatal LNS on cognitive development trajectory and time to achievement of selected gross motor milestones. TRIAL REGISTRATION: ClinicalTrials.gov NCT02145000.

Prenatal supplementation with multiple micronutrient supplements or medium-quantity lipid-based nutrient supplements has limited effects on child growth up to 24 months in rural Niger: a secondary analysis of a cluster randomized trial.

BACKGROUND: Prenatal multiple micronutrient supplementation (MMS) and lipid-based nutrient supplementation (LNS) can improve birth outcomes relative to iron-folic acid supplementation (IFA); however, effects on child postnatal growth remain unclear. OBJECTIVES: The aim was to compare the effect of prenatal MMS, medium-quantity LNS (MQ-LNS), and IFA on child growth up to 2 y of age. METHODS: We conducted a cluster randomized controlled trial of prenatal nutritional supplementation in Madarounfa, Niger. Villages were randomly assigned for pregnant women to receive IFA (17 villages, 1105 women), MMS (18 villages, 1083 women) or MQ-LNS (18 villages, 1144 women). Pregnant women received nutritional supplements weekly until delivery, and children were followed up monthly from 6-8 wk to 24 mo of age. We assessed the effect of prenatal MMS and MQ-LNS compared with IFA and the effect of prenatal MMS compared with MQ-LNS on child length-for-age z scores (LAZ), weight-for-age z scores (WAZ), and weight-for-length z scores (WLZ) at 24 mo of age using generalized linear models. In secondary analyses, we used mixed-effects models to assess the trajectories of anthropometric z scores longitudinally from 6-8 wk to 24 mo. RESULTS: Compared with IFA, MMS and MQ-LNS had no effect on child LAZ, WAZ, or WLZ at 24 mo of age (P > 0.05). Children in the MQ-LNS arm had significantly higher mid-upper arm circumference at 24 mo than children in the MMS arm: mean difference 0.50 cm (95% CI 0.10, 0.91 cm). WAZ and WLZ trajectories were more negative in the MQ-LNS arm compared with IFA and MMS, with lower z scores from 14 to 20 mo of age. However, WAZ and WLZ trajectories converged after 20 mo of age, and there were no differences by 24 mo of age. CONCLUSIONS: Prenatal MMS and MQ-LNS had limited effect on anthropometric measures of child growth up to 24 mo of age as compared with IFA in rural Niger.

Correction: Immunogenicity of an oral rotavirus vaccine administered with prenatal nutritional support in Niger: A cluster randomized clinical trial.

[This corrects the article DOI: 10.1371/journal.pmed.1003720.].

Prevalence of malaria in an area receiving seasonal malaria chemoprevention in Niger.

BACKGROUND: Malaria transmission is highly seasonal in Niger. Despite the introduction of seasonal malaria chemoprevention (SMC) in the Magaria District, malaria incidence remains high, and the epidemiology of malaria in the community is not well-understood. METHODS: Four cross-sectional, household-based malaria prevalence surveys were performed in the Magaria District of Niger between October 2016 and February 2018. Two occurred during the peak malaria season and two during the low malaria season. Individuals in each of three age strata (3-59 months, 5-9 years, and 10 years and above) were sampled in randomly-selected households. Capillary blood was collected by fingerprick, thick and thin blood films were examined. Microscopy was performed at Epicentre, Maradi, Niger, with external quality control. The target sample size was 396 households during the high-season surveys and 266 households during the low-season surveys. RESULTS: Prevalence of parasitaemia was highest in children aged 5-9 years during all four surveys, ranging between 53.6% (95%CI 48.8-63.6) in February 2018 and 73.2% (66.2-79.2) in September 2017. Prevalence of parasitaemia among children aged 3-59 months ranged between 39.6% (33.2-46.4) in February 2018 and 51.9% (45.1-58.6) in October 2016. Parasite density was highest in children aged 3-59 months during all four surveys, and was higher in high season surveys than in low season surveys among all participants. The prevalence of gametocytaemia in children aged 3-59 months ranged between 9.9% (6.5-14.8) in February 2018 and 19.3% (14.6-25.2) in October 2016. The prevalence of gametocytaemia in children aged 5-9 years ranged between 6.3% (3.5-11.1) in February 2018 and 18.5% (12.7-26.1) in October 2016. CONCLUSIONS: Asymptomatic malaria infection is highly prevalent in this area, even during the season with low incidence of clinical malaria. The high prevalence of parasitaemia in children aged 5-9 years warrants considering their inclusion in SMC programmes in this context.

An exploratory qualitative study of caregivers' knowledge, perceptions and practices related to hospital hygiene in rural Niger.

BACKGROUND: The risk of healthcare-associated infections is exacerbated by poor hygiene practices in health care facilities and can contribute to increased patient morbidity and mortality. In low-income settings, caregivers play a key role in maintaining proper hygiene during inpatient stays. We aimed to explore caregivers' knowledge, perceptions and practices related to hospital hygiene in a rural, sub-Saharan African setting. METHODS: We conducted an exploratory qualitative study among caregivers of children admitted to an inpatient therapeutic feeding center in Madarounfa, Niger. Individual interviews with 28 caregivers of hospitalized children were conducted to explore their knowledge, perceptions and practices of hygiene in the health facility. FINDINGS: Caregivers described a broad understanding of hygiene and reported knowledge of its importance in the hospital, particularly to prevent disease transmission and protect child health. Hygiene was perceived as a collective rather than individual responsibility. Caregivers reported on the poor hygiene practice of others and cited a lack of space and hygiene materials as barriers to correct hygiene practice. Caregivers described educational sessions and informal sharing with other caregivers as tools to gain knowledge and improve practice. CONCLUSION: This exploratory study is unique in describing the perspective of caregivers in a low-resource hospital setting, a group often underrepresented when designing health interventions to improve hospital hygiene. Our findings suggest a strong knowledge of hospital hygiene among caregivers in this setting, with positive perception of its importance in health promotion. Poor individual practice was reported but may be improved through additional education and provision of hygiene materials.

Etiology and Incidence of Moderate-to-Severe Diarrhea in Young Children in Niger.

BACKGROUND: High-resolution data on the etiology of childhood diarrhea in countries with the highest burden and mortality remain sparse and are needed to inform burden estimates and prioritize interventions. METHODS: We tested stool specimens collected between October 2014 and December 2017 from children under 2 years of age from the per-protocol population of a placebo-controlled clinical trial of a bovine rotavirus pentavalent vaccine (Rotasiil) in Niger. We tested 1729 episodes of moderate-to-severe diarrhea (Vesikari score ≥ 7) using quantitative PCR and estimated pathogen-specific burdens by age, season, severity, and trial intervention arm. RESULTS: The 4 pathogens with the highest attributable incidence of diarrhea were Shigella (7.2 attributable episodes per 100 child-years; 95% confidence interval: 5.2, 9.7), Cryptosporidium (6.5; 5.8, 7.2), rotavirus (6.4; 5.9, 6.7), and heat-stabile toxin-producing enterotoxigenic Escherichia coli (ST-ETEC) (6.2; 3.1, 7.7). Cryptosporidium was the leading etiology of severe diarrhea (Vesikari score ≥ 11) and diarrhea requiring hospitalization. Shigella was the leading etiology of diarrhea in children 12-23 months of age but also had a substantial burden in the first year of life, with 60.5% of episodes of severe shigellosis occurring in infants. Shigella, Cryptosporidium, and ST-ETEC incidence peaked during the warmer and wetter period and coincided with peak all-cause diarrhea incidence. CONCLUSIONS: In this high-burden setting, the leading diarrheal pathogens were Shigella, Cryptosporidium, rotavirus, and ST-ETEC, and each was disproportionately seen in infants. Vaccine development should target these pathogens, and the impact of vaccine schedule on diarrhea burden in the youngest children will need to be considered.

Exploring the relationships between wasting and stunting among a cohort of children under two years of age in Niger.

BACKGROUND: Wasting and stunting, physical growth manifestations of child undernutrition, have historically been considered separately with distinct interventions at the program, policy, and financing levels despite similar risk factors, overlapping burdens and multiplicative risk of death when the conditions are concurrent. The aim of this study was to elucidate shared risk factors and the temporal relationship between wasting and stunting among children under 2 years of age in rural Niger. METHODS: From August 2014 to December 2019, anthropometric data were collected every 4 weeks from 6 to 8 weeks to 24 months of age for 6567 children comprising 139,529 visits in Madarounfa, Niger. Children were defined as wasted if they had a weight-for-length Z-score < - 2 and stunted if they had a length-for-age Z-score < - 2 using the 2006 World Health Organization child growth standards. Parental, child, and socioeconomic risk factors for wasting and stunting at 6 and 24 months of age and the relationship between episodes of wasting, stunting and concurrent wasting-stunting were assessed using general estimating equations. RESULTS: Half of children (50%) were female, and 8.3% were born low birthweight (< 2500 g). Overall, at 24 months of age, 14% of children were wasted, 80% were stunted and 12% were concurrently wasted-stunted. We found that maternal short stature, male sex, and low birthweight were risk factors for wasting and stunting at 6 and 24 months, whereas higher maternal body mass index and household wealth were protective factors. Wasting at 6 and 24 months was predicted by a prior episodes of wasting, stunting, and concurrent wasting-stunting. Stunting at 6 and 24 months was similarly predicted by prior episodes of stunting and concurrent wasting-stunting at any prior age but only by prior episodes of wasting after 6 months of age. CONCLUSIONS: These data support a complex and dynamic bi-directional relationship between wasting and stunting in young children in rural Niger and an important burden of concurrent wasting-stunting in this setting. Further research to better understand the inter-relationships and mechanisms between these two conditions is needed in order to develop and target interventions to promote child growth. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02145000 .

A feasibility study using mid-upper arm circumference as the sole anthropometric criterion for admission and discharge in the outpatient treatment for severe acute malnutrition.

BACKGROUND: The World Health Organization recommends the use of a weight-for-height Z-score (WHZ) and/or mid-upper arm circumference (MUAC) as anthropometric criteria for the admission and discharge of young children for the community-based management of severe acute malnutrition. However, using MUAC as a single anthropometric criterion for admission and discharge in therapeutic nutritional programs may offer operational advantages to simplify admission processes at therapeutic nutritional centers and improve program coverage. METHODS: This pragmatic, non-randomized, intervention study compared a standard outpatient nutritional program (n = 824) for the treatment of uncomplicated severe acute malnutrition using WHZ < - 3 and/or MUAC< 115 mm and/or bipedal edema for admission and discharge to a program (n = 1019) using MUAC as the sole anthropometric criterion for admission (MUAC< 120 mm) and discharge (MUAC ≥125 mm at two consecutive visits) in the Tahoua Region of Niger. RESULTS: Compared to the standard program, the MUAC-only program discharged more children as recovered (70.1% vs. 51.6%; aOR 2.31, 95%CI 1.79-2.98) and fewer children as non-respondent or defaulters, based on respective program definitions. The risk of non-response was high in both programs. Three months post-discharge, children who were discharged after recovery in the MUAC-only program had lower WHZ and MUAC measures. Sixty-three children ineligible for the MUAC-only program but eligible for a standard program (MUAC ≥120 mm and WHZ < -3) were followed for twelve weeks and the anthropometric status of 69.8% of these children did not deteriorate (i.e. MUAC ≥120 mm) despite not immediately receiving treatment in the MUAC-only program. CONCLUSIONS: The results from this study share the first operational experience of using MUAC as sole anthropometric criterion for admission and discharge in Niger and overall support the consideration for MUAC-only programming: the MUAC-only model of care was associated with a higher recovery and a lower defaulter rate than the standard program with very few children found to be excluded from treatment with an admission criterion of MUAC < 120 mm. Further consideration of the appropriate MUAC-based discharge criterion as it relates to an increased risk of non-response and adverse post-discharge outcomes would be prudent.

Immunogenicity of an oral rotavirus vaccine administered with prenatal nutritional support in Niger: A cluster randomized clinical trial.

BACKGROUND: Nutritional status may play a role in infant immune development. To identify potential boosters of immunogenicity in low-income countries where oral vaccine efficacy is low, we tested the effect of prenatal nutritional supplementation on immune response to 3 doses of a live oral rotavirus vaccine. METHODS AND FINDINGS: We nested a cluster randomized trial within a double-blind, placebo-controlled randomized efficacy trial to assess the effect of 3 prenatal nutritional supplements (lipid-based nutrient supplement [LNS], multiple micronutrient supplement [MMS], or iron-folic acid [IFA]) on infant immune response (n = 53 villages and 1,525 infants with valid serology results: 794 in the vaccine group and 731 in the placebo group). From September 2015 to February 2017, participating women received prenatal nutrient supplement during pregnancy. Eligible infants were then randomized to receive 3 doses of an oral rotavirus vaccine or placebo at 6-8 weeks of age (mean age: 6.3 weeks, 50% female). Infant sera (pre-Dose 1 and 28 days post-Dose 3) were analyzed for anti-rotavirus immunoglobulin A (IgA) using enzyme-linked immunosorbent assay (ELISA). The primary immunogenicity end point, seroconversion defined as ≥3-fold increase in IgA, was compared in vaccinated infants among the 3 supplement groups and between vaccine/placebo groups using mixed model analysis of variance procedures. Seroconversion did not differ by supplementation group (41.1% (94/229) with LNS vs. 39.1% (102/261) with multiple micronutrients (MMN) vs. 38.8% (118/304) with IFA, p = 0.91). Overall, 39.6% (n = 314/794) of infants who received vaccine seroconverted, compared to 29.0% (n = 212/731) of infants who received placebo (relative risk [RR]: 1.36; 95% confidence interval [CI]: 1.18, 1.57, p < 0.001). This study was conducted in a high rotavirus transmission setting. Study limitations include the absence of an immune correlate of protection for rotavirus vaccines, with the implications of using serum anti-rotavirus IgA for the assessment of immunogenicity and efficacy in low-income countries unclear. CONCLUSIONS: This study showed no effect of the type of prenatal nutrient supplementation on immune response in this setting. Immune response varied depending on previous exposure to rotavirus, suggesting that alternative delivery modalities and schedules may be considered to improve vaccine performance in high transmission settings. TRIAL REGISTRATION: ClinicalTrials.gov NCT02145000.

Rotavirus vaccine efficacy up to 2 years of age and against diverse circulating rotavirus strains in Niger: Extended follow-up of a randomized controlled trial.

BACKGROUND: Rotavirus vaccination is recommended in all countries to reduce the burden of diarrhea-related morbidity and mortality in children. In resource-limited settings, rotavirus vaccination in the national immunization program has important cost implications, and evidence for protection beyond the first year of life and against the evolving variety of rotavirus strains is important. We assessed the extended and strain-specific vaccine efficacy of a heat-stable, affordable oral rotavirus vaccine (Rotasiil, Serum Institute of India, Pune, India) against severe rotavirus gastroenteritis (SRVGE) among healthy infants in Niger. METHODS AND FINDINGS: From August 2014 to November 2015, infants were randomized in a 1:1 ratio to receive 3 doses of Rotasiil or placebo at approximately 6, 10, and 14 weeks of age. Episodes of gastroenteritis were assessed through active and passive surveillance and graded using the Vesikari score. The primary endpoint was vaccine efficacy of 3 doses of vaccine versus placebo against a first episode of laboratory-confirmed SRVGE (Vesikari score ≥ 11) from 28 days after dose 3, as previously reported. At the time of the primary analysis, median age was 9.8 months. In the present paper, analyses of extended efficacy were undertaken for 3 periods (28 days after dose 3 to 1 year of age, 1 to 2 years of age, and the combined period 28 days after dose 3 to 2 years of age) and by individual rotavirus G type. Among the 3,508 infants included in the per-protocol efficacy analysis (mean age at first dose 6.5 weeks; 49% male), the vaccine provided significant protection against SRVGE through the first year of life (3.96 and 9.98 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 60.3%, 95% CI 43.6% to 72.1%) and over the entire efficacy follow-up period up to 2 years of age (2.13 and 4.69 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 54.7%, 95% CI 38.1% to 66.8%), but the difference was not statistically significant in the second year of life. Up to 2 years of age, rotavirus vaccination prevented 2.56 episodes of SRVGE per 100 child-years. Estimates of efficacy against SRVGE by individual rotavirus genotype were consistent with the overall protective efficacy. Study limitations include limited generalizability to settings with administration of oral polio virus due to low concomitant administration, limited power to assess vaccine efficacy in the second year of life owing to a low number of events among older children, potential bias due to censoring of placebo children at the time of study vaccine receipt, and suboptimal adapted severity scoring based on the Vesikari score, which was designed for use in settings with high parental literacy. CONCLUSIONS: Rotasiil provided protection against SRVGE in infants through an extended follow-up period of approximately 2 years. Protection was significant in the first year of life, when the disease burden and risk of death are highest, and against a changing pattern of rotavirus strains during the 2-year efficacy period. Rotavirus vaccines that are safe, effective, and protective against multiple strains represent the best hope for preventing the severe consequences of rotavirus infection, especially in resource-limited settings, where access to care may be limited. Studies such as this provide valuable information for the planning of national immunization programs and future vaccine development. TRIAL REGISTRATION: ClinicalTrials.gov NCT02145000.

Investigating persistent measles dynamics in Niger and associations with rainfall.

Measles is a major cause of child mortality in sub-Saharan Africa. Current immunization strategies achieve low coverage in areas where transmission drivers differ substantially from those in high-income countries. A better understanding of measles transmission in areas with measles persistence will increase vaccination coverage and reduce ongoing transmission. We analysed weekly reported measles cases at the district level in Niger from 1995 to 2004 to identify underlying transmission mechanisms. We identified dominant periodicities and the associated spatial clustering patterns. We also investigated associations between reported measles cases and environmental drivers associated with human activities, particularly rainfall. The annual and 2-3-year periodicities dominated the reporting data spectrum. The annual periodicity was strong with contiguous spatial clustering, consistent with the latitudinal gradient of population density, and stable over time. The 2-3-year periodicities were weaker, unstable over time and had spatially fragmented clustering. The rainy season was associated with a lower risk of measles case reporting. The annual periodicity likely reflects seasonal agricultural labour migration, whereas the 2-3-year periodicity potentially results from multiple mechanisms such as reintroductions and vaccine coverage heterogeneity. Our findings suggest that improving vaccine coverage in seasonally mobile populations could reduce strong measles seasonality in Niger and across similar settings.

Adherence and Population Pharmacokinetic Properties of Amodiaquine When Used for Seasonal Malaria Chemoprevention in African Children.

Poor adherence to seasonal malaria chemoprevention (SMC) might affect the protective effectiveness of SMC. Here, we evaluated the population pharmacokinetic properties of amodiaquine and its active metabolite, desethylamodiaquine, in children receiving SMC under directly observed ideal conditions (n = 136), and the adherence of SMC at an implementation phase in children participating in a case-control study to evaluate SMC effectiveness (n = 869). Amodiaquine and desethylamodiaquine concentration-time profiles were described simultaneously by two-compartment and three-compartment disposition models, respectively. The developed methodology to evaluate adherence showed a sensitivity of 65-71% when the first dose of SMC was directly observed and 71-73% when no doses were observed in a routine programmatic setting. Adherence simulations and measured desethylamodiaquine concentrations in the case-control children showed complete adherence (all doses taken) in < 20% of children. This result suggests that more efforts are needed urgently to improve the adherence to SMC among children in this area.

Clinical diagnostic evaluation of HRP2 and pLDH-based rapid diagnostic tests for malaria in an area receiving seasonal malaria chemoprevention in Niger.

BACKGROUND: Rapid diagnostic tests (RDT) for malaria are common, but their performance varies. Tests using histidine-rich protein 2 (HRP2) antigen are most common, and many have high sensitivity. HRP2 tests can remain positive for weeks after treatment, limiting their specificity and usefulness in high-transmission settings. Tests using Plasmodium lactate dehydrogenase (pLDH) have been less widely used but have higher specificity, mostly due to a much shorter time to become negative. METHODS: A prospective, health centre-based, diagnostic evaluation of two malaria RDTs was performed in rural Niger during the high malaria transmission season (3-28 October, 2017) and during the low transmission season (28 January-31 March, 2018). All children under 5 years of age presenting with fever (axillary temperature > 37.5 °C) or history of fever in the previous 24 h were eligible. Capillary blood was collected by finger prick. The SD Bioline HRP2 (catalog: 05FK50) and the CareStart pLDH(pan) (catalog: RMNM-02571) were performed in parallel, and thick and thin smears were prepared. Microscopy was performed at Epicentre, Maradi, Niger, with external quality control. The target sample size was 279 children with microscopy-confirmed malaria during each transmission season. RESULTS: In the high season, the sensitivity of both tests was estimated at > 99%, but the specificity of both tests was lower: 58.0% (95% CI 52.1-63.8) for the pLDH test and 57.4% (95% CI 51.5-63.1) for the HRP2 test. The positive predictive value was 66.3% (95% CI 61.1-71.2) for both tests. In the low season, the sensitivity of both tests dropped: 91.0% (95% CI 85.3-95.0) for the pLDH test and 85.8% (95% CI 79.3-90.9) for the HRP2 test. The positive predictive value remained low for both tests in the low season: 60.5% (95% CI 53.9-66.8) for the pLDH test and 61.9% (55.0-68.4) for the HRP2 test. Performance was similar across different production lots, gender, age of the children, and, during the high season, time since the most recent distribution of seasonal malaria chemoprevention. CONCLUSIONS: The low specificity of the pLDH RDT in this setting was unexpected and is not easily explained. As the pLDH test continues to be introduced into new settings, the questions raised by this study will need to be addressed.

Severe Acute Malnutrition Results in Lower Lumefantrine Exposure in Children Treated With Artemether-Lumefantrine for Uncomplicated Malaria.

Severe acute malnutrition (SAM) has been reported to be associated with increased malaria morbidity in Sub-Saharan African children and may affect the pharmacology of antimalarial drugs. This population pharmacokinetic (PK)-pharmacodynamic study included 131 SAM and 266 non-SAM children administered artemether-lumefantrine twice daily for 3 days. Lumefantrine capillary plasma concentrations were adequately described by two transit-absorption compartments followed by two distribution compartments. Allometrically scaled body weight and an enzymatic maturation effect were included in the PK model. Mid-upper arm circumference was associated with decreased absorption of lumefantrine (25.4% decreased absorption per 1 cm reduction). Risk of recurrent malaria episodes (i.e., reinfection) were characterized by an interval-censored time-to-event model with a sigmoid maximum-effect model describing the effect of lumefantrine. SAM children were at risk of underexposure to lumefantrine and an increased risk of malaria reinfection compared with well-nourished children. Research on optimized regimens should be considered for malaria treatment in malnourished children.

Acceptability and utilization of a lipid-based nutrient supplement formulated for pregnant women in rural Niger: a multi-methods study.

BACKGROUND: In food insecure settings, it may be difficult for pregnant women to meet increased nutritional needs through traditional diets. A promising new strategy to fill nutrient gaps in pregnancy involves the provision of lipid-based nutrient supplements (LNS). We aimed to assess the acceptability and utilization of a 40 g LNS formulation (Epi-E) with increased micronutrient content relative to the recommended daily allowance among pregnant women in rural Niger. METHODS: We conducted a two-part, multi-methods study among pregnant women presenting to antenatal care in Madarounfa, Niger during two periods (Ramadan and non-Ramadan). Part 1 included two LNS test meals provided at the health center, and Part 2 included a 14-day home trial to simulate more realistic conditions outside of the health center. Open- and closed-ended questions were used to assess organoleptic properties of Epi-E using a 5-point hedonic scale after the test meals, as well as utilization and willingness to pay for Epi-E after the 14-day home trial. RESULTS: Participants consumed more than 90% of the test meal in both periods. Epi-E was rated highly in terms of overall liking, color, taste and smell during test meals in both periods (median 5/5 for all); only time, mode and frequency of consumption varied between Ramadan and non-Ramadan periods in observance of daily fasting during the holy month. CONCLUSION: Epi- E, a 40 g LNS formulation with increased micronutrient content, was highly acceptable among pregnant women in rural Niger, and utilization was guided by household and individual considerations that varied by time period. This formulation can be further tested as a potential strategy to improve the nutritional status of pregnant women in this context. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02145000. Registered 22 May 2014.

Safety of a heat-stable rotavirus vaccine among children in Niger: Data from a phase 3, randomized, double-blind, placebo-controlled trial.

BACKGROUND: Rotavirus remains a major cause of diarrhea among children under 5 years of age. The efficacy of RotaSIIL, a pentavalent rotavirus vaccine, was shown in an event-driven trial in Niger. We describe the two-year safety follow-up of this trial. METHODS: Follow-up of safety outcomes began upon administration of the first dose of RotaSIIL or placebo. Adverse events were followed until 28 days after the third dose, and serious adverse events were followed until 2 years of age. Suspected cases of intussusception were evaluated at first point of contact and then referred to hospital for surgical evaluation. Causes of death were obtained by chart review and verbal autopsy. Passive surveillance was carried out in health centers. Community health workers carried out active surveillance in villages. Between-group differences were evaluated using the chi-squared test and Fisher's exact test. RESULTS: A total of 4092 children were randomized, and 4086 received at least one dose of RotaSIIL or placebo, constituting the intention-to-treat population, who accrued a total of 7385 child-years of follow-up time. At two years of follow-up, 58 (2.8%) participants who received RotaSIIL and 49 (2.4%) participants who received placebo had died (p = 0.38). Most deaths were due to infectious causes common to the study area. One participant had confirmed intussusception, 542 days after receiving the third dose of RotaSIIL. A total of 395 (19.3%) participants receiving RotaSIIL and 419 (20.5%) participants receiving placebo experienced any serious adverse event (p = 0.36). Most serious adverse events were hospitalizations due to infection (malaria, lower respiratory tract infection and gastroenteritis) or marasmus. Overall, 1474 (72.1%) participants receiving RotaSIIL and 1456 (71.1%) participants receiving placebo had at least one adverse event (p = 0.49) in the follow-up period. CONCLUSIONS: At two years of follow-up, RotaSIIL was found to be safe. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02145000.