Contact

  • Academic
    suhi@stanford.edu
    University - Student Department: Epidemiology and Population Health Position: Graduate

All Publications

  • Effects of household concrete floors on maternal and child health: the CRADLE trial - a randomised controlled trial protocol. BMJ open Rahman, M., Jahan, F., Hanif, S., Yeamin, A., Shoab, A. K., Andrews, J. R., Lu, Y., Billington, S., Pilotte, N., Shanta, I. S., Jubair, M., Rahman, M., Kabir, M., Haque, R., Tofail, F., Hossain, M. S., Mahmud, Z. H., Ercumen, A., Benjamin-Chung, J. 2025; 15 (3): e090703

    Abstract

    Early life soil-transmitted helminth (STH) infection and diarrhoea are associated with growth faltering, anaemia, impaired child development and mortality. Exposure to faecally contaminated soil inside the home may be a key contributor to enteric infections, and a large fraction of rural homes in low-income countries have soil floors. The objective of this study is to measure the effect of installing concrete floors in homes with soil floors on child STH infection and other maternal and child health outcomes in rural Bangladesh.The Cement-based flooRs AnD chiLd hEalth trial is an individually randomised trial in Sirajganj and Tangail districts, Bangladesh. Households with a pregnant woman, a soil floor, walls that are not made of mud and no plan to relocate for 3 years will be eligible. We will randomise 800 households to intervention or control (1:1) within geographical blocks of 10 households to account for strong geographical clustering of enteric infection. Laboratory staff and data analysts will be blinded; participants will be unblinded. We will instal concrete floors when the birth cohort is in utero and measure outcomes at child ages 3, 6, 12, 18 and 24 months. The primary outcome is prevalence of any STH infection (Ascaris lumbricoides, Necator americanus or Trichuris trichiura) detected by quantitative PCR at 6, 12, 18 or 24 months follow-up in the birth cohort. Secondary outcomes include household floor and child hand contamination with Escherichia coli, extended-spectrum beta-lactamase producing E. coli and STH DNA; child diarrhoea, growth and cognitive development; and maternal stress and depression.Study protocols have been approved by institutional review boards at Stanford University and the International Centre for Diarrheal Disease Research, Bangladesh. We will report findings on ClinicalTrials.gov, in peer-reviewed publications and in stakeholder workshops in Bangladesh.NCT05372068.

    View details for DOI 10.1136/bmjopen-2024-090703

    View details for PubMedID 40032381

  • Pathogens and Antimicrobial Resistance Genes in Household Environments: A Study of Soil Floors and Cow Dung in Rural Bangladesh. bioRxiv : the preprint server for biology Nguyen, A. T., Ratnasiri, K., Heitmann, G. B., Tazin, S., Anderson, C., Hanif, S., Yeamin, A., Shoab, A. K., Shanta, I. S., Jahan, F., Hossain, S., Mahmud, Z. H., Jubair, M., Rahman, M., Rahman, M., Ercumen, A., Benjamin-Chung, J. 2024

    Abstract

    In low- and middle-income countries, living in homes with soil floors and animal cohabitation may expose children to fecal organisms, increasing risk of enteric and antimicrobial-resistant infections. Our objective was to understand whether cow cohabitation in homes with soil floors in rural Bangladesh contributed to the presence and diversity of potential pathogens and antimicrobial resistance genes (ARGs) in the home. In 10 randomly selected households in rural Sirajganj District, we sampled floor soil and cow dung, which is commonly used as sealant in soil floors. We extracted DNA and performed shotgun metagenomic sequencing to explore potential pathogens and ARGs in each sample type. We detected 6 potential pathogens in soil only, 49 pathogens in cow dung only, and 167 pathogens in both soil and cow dung. Pathogen species with relative abundances >5% in both soil floors and cow dung from the same households included E. coli (N=8 households), Salmonella enterica (N=6), Klebsiella pneumoniae (N=2), and Pseudomonas aeruginosa (N=1). Cow dung exhibited modestly higher pathogen genus richness compared to soil floors (Wilcoxon signed-rank test p=0.002). Using Bray-Curtis dissimilarity, pathogen species community composition differed between floors and cow dung (PERMANOVA p<0.001). All soil floors and cow dung samples contained ARGs against antibiotic classes including sulfonamides, rifamycin, aminoglycosides, lincosamides, and tetracycline. Paired floor and cow dung samples shared ARGs against rifamycin. Our findings support the development of interventions to reduce soil and animal feces exposure in rural, low-income settings.

    View details for DOI 10.1101/2024.12.06.627269

    View details for PubMedID 39677809

    View details for PubMedCentralID PMC11642972

  • Flooding and elevated prenatal depression in a climate-sensitive community in rural Bangladesh: a mixed methods study. medRxiv : the preprint server for health sciences Hanif, S., Momo, J. E., Jahan, F., Goldberg, L., Herbert, N., Yeamin, A., Shoab, A. K., Akhter, R. M., Roy, S. K., Heitmann, G. B., Ercumen, A., Rahman, M., Tofail, F., Wong-Parodi, G., Benjamin-Chung, J. 2024

    Abstract

    Prenatal depression can have lasting adverse impacts on child health. Little is known about the impact of floods on prenatal depression in low- and middle-income countries.We conducted a cross-sectional survey of 881 pregnant women from September 24, 2023 to July 19, 2024 in riverine communities in rural Bangladesh. We recorded participant-reported flooding in the past 6 months, administered the Edinburgh Postnatal Depression Scale (EPDS), and obtained water level data and remote sensing data on distance to surface water. We fit generalized linear and log-linear models adjusting for month, wealth, education, age, and gestational age. We conducted 2 focus group discussions with 20 adult women.3.6% of compounds were flooded in the past 6 months. Compound flooding was associated with elevated depression (adjusted prevalence ratio (aPR) = 2.08, 95% CI 1.14, 3.51) and thoughts of self-harm (aPR=8.40, 95% CI 4.19, 16.10). Latrine flooding was associated with higher depression (aPR=3.58, 95% CI 1.49, 7.29)). Higher water levels and shorter distance to permanent surface water were significantly associated with mean EPDS scores. Focus groups revealed that domestic violence, inadequate sanitation, gendered vulnerabilities in accessing latrines, childcare difficulties, and food insecurity were key drivers of depression due to floods. Flood preparedness strategies included relocation, storing food, and home modifications.Flooding, higher water levels, and proximity to water bodies were associated with prenatal depression in a rural, low-income setting. Inadequate sanitation and hygiene infrastructure were particularly strong drivers of depression.Eunice Kennedy Shriver National Institute of Child Health and Human Development.

    View details for DOI 10.1101/2024.11.25.24317922

    View details for PubMedID 39649600

    View details for PubMedCentralID PMC11623739

  • Intermittent preventive treatment for malaria in pregnancy and infant growth: a mediation analysis of a randomised trial. EBioMedicine Tong, Y., Ratnasiri, K., Hanif, S., Nguyen, A. T., Roh, M. E., Dorsey, G., Kakuru, A., Jagannathan, P., Benjamin-Chung, J. 2024; 109: 105397

    Abstract

    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.We analysed data from 633 infants born to mothers enrolled in a randomised trial of monthly IPTp with dihydroartemisinin-piperaquine (DP) vs. sulfadoxine-pyrimethamine (SP) (NCT02793622). Weight and length were measured from 0 to 12 months of age. Using generalised 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 anaemia, maternal inflammation-related proteins, preterm birth, birth length, and birth weight. Mediation models adjusted for infant sex, gravidity, gestational age at enrolment, maternal age, maternal parasitaemia at enrolment, education, and wealth.SP increased mean LAZ by 0.18-0.28 Z from birth through age 4 months compared to DP, while DP increased mean WLZ by 0.11-0.28 Z from 2 to 8 months compared to SP among infants of multigravidae; at these ages, confidence intervals for mean differences excluded 0. We did not observe differences among primigravida. Mediators of SP included birth weight, birth length, maternal stem cell factor, and DNER. Mediators of DP included placental malaria and birth length, maternal IL-18, CDCP1, and CD6 at delivery.In high malaria transmission settings, this exploratory study suggests different IPTp regimens may influence infant growth among multigravidae, potentially through distinct pathways, in the exclusive breastfeeding period, when few other interventions are available.Stanford Center for Innovation in Global Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bill & Melinda Gates Foundation.

    View details for DOI 10.1016/j.ebiom.2024.105397

    View details for PubMedID 39418986

  • Effects of household concrete floors on maternal and child health - the CRADLE trial: a randomised controlled trial protocol. medRxiv : the preprint server for health sciences Rahman, M., Jahan, F., Hanif, S., Yeamin, A., Shoab, A. K., Andrews, J. R., Lu, Y., Billington, S., Pilotte, N., Shanta, I. S., Jubair, M., Rahman, M., Kabir, M., Haque, R., Tofail, F., Hossain, S., Mahmud, Z. H., Ercumen, A., Benjamin-Chung, J. 2024

    Abstract

    Early life soil-transmitted helminth infection and diarrhea are associated with growth faltering, anemia, impaired child development, and mortality. Exposure to fecally contaminated soil inside the home may be a key contributor to enteric infections, and a large fraction of rural homes in low-income countries have soil floors. The objective of this study is to measure the effect of installing concrete floors in homes with soil floors on child soil-transmitted helminth infection and other maternal and child health outcomes in rural Bangladesh.The Cement-based flooRs AnD chiLd hEalth (CRADLE) trial is an individually randomised trial in Sirajganj and Tangail districts, Bangladesh. Households with a pregnant woman, a soil floor, walls that are not made of mud will be eligible, and no plan to relocate for 3 years. We will randomise 800 households to intervention or control (1:1) within geographic blocks of 10 households to account for strong geographic clustering of enteric infection. Laboratory staff and data analysts will be blinded; participants will be unblinded. We will install concrete floors when the birth cohort is in utero and measure outcomes at child ages 3, 6, 12, 18, and 24 months. The primary outcome is prevalence of any soil-transmitted helminth infection (Ascaris lumbricoides, Necator americanus, or Trichuris trichiura) detected by qPCR at 6, 12, 18, or 24 months follow-up in the birth cohort. Secondary outcomes include household floor and child hand contamination with E. coli, extended-spectrum beta-lactamase producing E. coli, and soil-transmitted helminth DNA; child diarrhea, growth, and cognitive development; and maternal stress and depression.Study protocols have been approved by institutional review boards at Stanford University and the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b). We will report findings on ClinicalTrials.gov, in peer-reviewed publications, and in stakeholder workshops in Bangladesh.NCT05372068, pre-results.

    View details for DOI 10.1101/2024.07.26.24311076

    View details for PubMedID 39108529

    View details for PubMedCentralID PMC11302711

  • Pathways through which intermittent preventive treatment for malaria in pregnancy influences child growth faltering: a mediation analysis. medRxiv : the preprint server for health sciences Tong, Y., Ratnasiri, K., Hanif, S., Nguyen, A. T., Roh, M. E., Dorsey, G., Kakuru, A., Jagannathan, P., Benjamin-Chung, J. 2024

    Abstract

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

    View details for DOI 10.1101/2024.06.09.24308656

    View details for PubMedID 38947035

    View details for PubMedCentralID PMC11213035