Stéphane Verguet

Background: Active case finding (ACF) for tuberculosis (TB) can reduce transmission, yet efficient targeting requires high-quality surveillance data. We investigated the potential costs and impact of targeted ACF, guided by local estimates of the annual risk of TB infection (ARTI) derived from Mycobacterium tuberculosis ( Mtb ) immunoreactivity survey data in children aged Mtb immunoreactivity survey data could substantially improve health impact and cost-effectiveness compared to untargeted approaches. However, low-cost approaches for collecting these data are needed for wider adoption.

Background: Maternal immunization (MI) can prevent major infectious diseases in mothers and children by boosting the immunity of pregnant women. Antenatal care (ANC) delivery platforms could be leveraged to effectively provide MI. Adding MIs into ANC could potentially enhance ANC services, positively influencing both maternal and infant health outcomes and yielding broader benefits. We model these potential ANC-mediated health benefits in five low- and middle-income countries: Ethiopia, Ghana, Kenya, Pakistan, and South Africa. Methods: We first developed a conceptual framework delineating pathways through which MI-ANC could enhance ANC utilization and quality, leading to improved care-seeking for facility delivery, postnatal care, and major childhood vaccinations (e.g., measles, diphtheria-pertussis-tetanus [DPT] third dose), as well as decreased infant mortality. Using a decision-analytic model informed by Demographic and Health Survey data, we simulated the potential benefits of MI-ANC delivery across socioeconomic groups at varying hypothetical MI coverage levels. Results: MI-ANC integration would be associated with improvements in maternal and child health outcomes across all countries studied, mediated through enhanced engagement with ANC services. Under a scenario of full MI-ANC coverage, for example, infant mortality in Ethiopia’s poorest quintile was projected to decline from approximately 60 to 50 deaths per 1,000 live births. In-facility delivery rates were estimated to increase from 11% to 35%, postnatal care utilization from 4% to 11%, measles-containing vaccine coverage from 43% to 71%, and DPT3 immunization from 36% to 63%. These improvements would vary substantially by country and socioeconomic group, with the largest gains observed in populations with lower baseline ANC utilization. Conclusions: Integrating MIs into ANC services has the potential to yield ANC-mediated health benefits, particularly in settings with low baseline ANC utilization. These findings can help inform priority-setting, support the design of targeted pilot programs, and guide future empirical implementation research on the possible broader impacts of MI-ANC delivery.

Background: Poverty alleviation is a major global development goal. Vaccines have the potential to provide financial risk protection (FRP) by preventing illnesses and associated healthcare costs. We estimate the lifetime FRP benefits generated by major vaccines among individuals vaccinated between 2000 and 2030 in low- and middle-income countries (LMICs). Methods and findings: We developed a microsimulation model to quantify the number of cases of catastrophic health expenditure (CHE) averted by a range of vaccines in 52 Gavi-eligible countries, stratified by wealth quintile. Vaccines protecting against five pathogens were considered, i.e., hepatitis B (routine and birth dose vaccine), Haemophilus influenzae type B, rotavirus, measles (routine and supplementary campaign vaccine), and Streptococcus pneumoniae . Model inputs were obtained from secondary data sources, including infection reduction rates under various immunization coverage scenarios, out-of-pocket health expenditures, transportation costs, wage losses, and healthcare utilization associated with disease treatment and consumption expenditures. CHE cases were defined as exceeding 10% of annual consumption, with sensitivity analyses conducted using thresholds of 25% and 40%, as well as impoverishing health expenditures were estimated. All vaccines, singly and collectively, showed a large impact on FRP and could avert ~200 million CHE cases across 52 Gavi-eligible countries from 2000 to 2030. Importantly, about half of all CHE cases were prevented among the poorest quintiles. When evaluated at a 10% threshold for CHE, the first dose of measles vaccine stood out in averting around 1,400 CHE cases per 10,000 vaccinated individuals in the poorest quintile, that is a total of 44 million CHE cases averted. A key limitation is the assumption of uniform disease risks in the absence of vaccination across quintiles, which may underestimate benefits for poorer groups. Conclusions: Vaccines can provide substantial FRP benefits, particularly among the most disadvantaged populations. Sustained investments to ensure vulnerable populations receive vaccinations in LMICs can therefore not only improve health outcomes but also contribute to poverty reduction.

To develop new methods to analyse the distributions of diarrhoea, pneumonia and measles deaths in children younger than 5 years across wealth quintiles. We used Demographic and Health Surveys conducted since 2013 from 21 sub-Saharan African countries. We implemented multidimensional optimization techniques to estimate the joint impact of risk factors (that is, stunting, wasting, underweight, vitamin A deficiency and unsafe sanitation), immunization coverage and treatment utilization, on the distribution of deaths from diarrhoea, pneumonia and measles across wealth quintiles in each country. For each country, we created wealth-related gradients to show the risk of dying from either diarrhoea, pneumonia or measles. Across all countries and diseases, the risks of dying from diarrhoea, pneumonia and measles decrease with increasing household wealth: children in the wealthiest quintile are at the lowest risk (set to 1), except in a few rare instances. Yet, the magnitudes of these estimated risk gradients varied considerably across diseases and countries, from under 2 to above 10. Wealth-related risks of dying seemed to be unrelated to the countries' levels of under-5 mortality. We estimate that inequalities in deaths from diarrhoea, pneumonia and measles are large in many countries of sub-Saharan Africa, with more deaths occurring among children in the poorest wealth quintiles compared with the richest. Our new and generalizable methods can help research on health disparities to explore new directions.