Contributions to Research
The primary focus of my research is on the discovery and translation of interventions to enhance maternal and child health and development. Over the past 25 years my group has led the design and implementation of more than 30 randomized controlled trials of maternal/neonatal and child/adolescent health, and infectious diseases, with emphasis on nutritional factors. We also undertake observational studies to understand the broader epidemiology of global health challenges, with a focus on developing countries in Africa and Asia. In the past 15 years, we have expanded our work to study the scale up and translation of various interventions that we and others have shown to be efficacious, and we pursue this in partnerships that integrate multiple public health disciplines. Our findings are disseminated through more than 450 papers to date that I have authored or co-authored.
Maternal and Child/Adolescent Health
About five million children under age five die each year and close to 200 million children have not reached their optimal development. Malnutrition is the underlying contributing factor in close to a half of all child deaths, and similarly it is a significant contributor to poor child and adolescent development. We examine the inter-relationships of prenatal nutrition, adverse pregnancy outcomes, maternal and child/adolescent health, and long term disability and economic productivity.
Two key findings of our recent work include: (a) In a recently completed randomized placebo-controlled trial, we have examined concerns about the safety of daily prenatal iron supplements in malaria-endemic regions, and have shown that iron provided to iron-replete pregnant women resulted in significant reductions in the risks of anemia and iron deficiency, and had no effect on the risk of placental malaria when adequate malaria prevention measures are in place. In a systematic review of 92 studies, we have documented the large benefits of prenatal iron supplements on maternal and birth outcomes across geographic settings, and provide strong rationale for programs to scale up the integration of this intervention into routine antenatal care. (b) In placebo controlled trials we have shown that multiple micronutrient supplements compared with standard of care prenatal iron and folate supplements resulted in significant reductions in intrauterine growth retardation and perinatal mortality. In a systematic review of the literature and meta-analysis including our own trials, we make the case that standard prenatal supplements in developing countries should include multiple micronutrients in light of greater efficacy, and comparable cost and feasibility relative to iron and folate only supplements.
Our group has completed several clinical trials (and others are ongoing) to determine the efficacy of various other interventions provided to pregnant women and/or children. We analyze data and utilize a large repository of specimens from these studies to examine the contributions of dietary intake assessed using repeated 24 hour recalls and food frequency questionnaires, exclusive breastfeeding and complementary infant feeding, and biomarkers of nutritional status and immunologic and inflammatory states, on maternal and child health and disease. We are expanding our work to address the rising tide of non-communicable diseases, with emphasis on women and children, and are also examining the state of adolescent health and consequences of maternal and child health risk factors and interventions on child/adolescent development, schooling, and long term economic and health outcomes.
Infections remain major causes of morbidity and mortality, and contribute to a vicious cycle that increases the risk of malnutrition and weakens the immune system, leading to higher risk and severity of new infections. We conduct randomized trials to determine the safety and efficacy of nutritional (and other) interventions to interrupt this cycle. In a large randomized trial among HIV-infected adults, we reported that a daily multivitamin supplement provided to individuals who were in early stages of HIV disease significantly improved immune status, reduced rates of wasting and anemia, slowed clinical disease progression, and improved survival. Our studies, with others, contributed to the evidence promoting the provision of nutritional supplements as adjunct preventive therapy to prolong the time needed before antiretroviral therapy is warranted.
We completed several clinical trials (and others are ongoing) to examine the efficacy of interventions provided to patients with active TB and other infectious diseases. We examine the role of micronutrient status, other aspects of nutritional status (using anthropometry, dietary intake), and antiretroviral drugs on the rate of HIV disease progression among adults and children, and the risk of mother-to-child transmission of HIV-1.
Our team is leading efforts with partners in several African countries and India to advance knowledge on the direct and indirect impacts of COVID-19 and the relationships of infection to nutrition and maternal and child health.
Starting in 2004, we have worked with our partners in Tanzania to introduce on a large scale interventions for care and treatment for HIV/AIDS in the Dar es Salaam region (~ 150,000 patients) with support from the President’s Emergency Plan for AIDS Relief (PEPFAR Track 1 grantees). In addition to major efforts to introduce antiretroviral therapy, training of all cadres of health workers, strengthening supply chain of drugs and diagnostics, and enhancing capacity for quality care and laboratory monitoring, our efforts included establishing a robust evaluation agenda that we used to develop lessons learnt that we disseminated through our publications. We culminated this PEPFAR effort by the establishment of an independent Tanzanian non-governmental organization, Management and Development for Health (MDH) to whom we transitioned program activities, and with whom we continue to collaborate on academic pursuits.
In partnership with colleagues across Harvard and other institutions, we convened a multi-year program around agriculture, nutrition and health. The program addresses and documents the existing gaps between agricultural development and its unfulfilled health and nutritional benefits; advances the research agenda for scaling up proven agricultural and nutritional interventions for optimal health; and provides the opportunity for experts in multi-disciplinary fields to interact in an effort to establish a common language to better understand the full pathway of change from agricultural and nutritional processes to improvements in health at the population level.
We are pursuing further efforts to address the problems of chronic hunger, hidden hunger, and maternal and neonatal mortality by providing interventions that are simple, affordable, and effective and applying delivery mechanisms that strengthen health systems and bridge the gaps between health facilities and the community. Our efforts are being extended to include partnership with institutions in Ethiopia applying our model of convening, building local capacity, scaling up and transforming, and stepping back to a supportive technical role.
Contributions to Education
Fostering sustainable research capacity has been a long-term goal of my group. I teach nutrition and global health courses for both graduate students at the Harvard Chan School and undergraduate students at Harvard College. To advance this area, I have led the work with colleagues across departments at the Harvard Chan School to establish the Nutrition and Global Health Concentration.
We have established strong links with partners in multiple African sites. To enable greater synergy, I have led the development of the Africa Research Implementation Science and Education (ARISE) Network to enable South-South and South-North partnership. We are also developing stronger connections with universities in other regions where our faculty are active in the areas of nutrition and global health, to start with partners in Brazil, Bangladesh, China and India. Our research collaborations over the past 25 years in Tanzania have led us to establish the Africa Academy for Public Health (AAPH) as a Harvard affiliate in 2009, an independent organization registered in Tanzania with the mission to improve heath in the Africa region through collaborative research, education, and knowledge translation. AAPH facilitates cutting-edge doctoral and post-doctoral level training of public health leaders in multidisciplinary fields.
MBBS, 1986, Faculty of Medicine, University of Khartoum
MPH (Public Health), 1989, Harvard School of Public Health
MS (Maternal and Child Health), 1991, Harvard School of Public Health
DrPH (Epidemiology and Nutrition), 1992, Harvard School of Public Health