Publications

Vaccine effectiveness (VE) studies conducted between June 2021 and August 2023 in Egypt, Pakistan, Iran, and Jordan assessed the real-world performance of COVID-19 vaccines across different clinical outcomes. The studies found that for health workers, an additional mRNA vaccine dose showed substantial protection against symptomatic infection, while results for other vaccines and outcomes were inconclusive. Among severe acute respiratory infection (SARI) patients, VE of a complete primary series against hospitalization was modest, highlighting the need for future VE studies to overcome late-pandemic design challenges and leverage improved country capacities. Download paper here

Guinea’s national malaria program employed a subnational tailoring (SNT) approach to optimize its 2024-2026 operational plan by using local data to prioritize malaria interventions by district. The SNT team stratified malaria risk and determinants, assessed intervention targeting criteria, and used modeling to predict the impact of various strategies, enabling the selection of the most appropriate interventions like indoor residual spray, dual-action nets, and malaria vaccines. This data-driven approach successfully mobilized resources and allowed Guinea to adapt its malaria strategy at the district level for the first time. Download preprint here

An agent-based model of Plasmodium falciparum transmission was used to simulate malaria morbidity and mortality in Nigeria’s 774 LGAs under four possible intervention strategies from 2020 to 2030. The scenarios represented the previously implemented plan (business-as-usual), the NMSP at an 80% or higher coverage level and two prioritized plans according to the resources available to Nigeria. Download paper here

Using an individual-based mathematical model, allowed to address uncertainties about scheduling PMC alone or in combination with malaria vaccines like RTS,S to provide additional evidence and improved understanding required to accelerate policy adoption of PMC in countries with high malaria burden in children. Simulated PMC with up to seven doses during the first eighteen months of age showed an added benefit in impact against clinical and severe malaria. Across all the PMC schedules tested, there was a complementary effect between PMC and RTS,S, providing a continuum of protection in children under the age of two years. Download publication here

We used a stochastic, compartmental transmission model to evaluate the performance of various surveillance indicators at reliably triggering an alarm in response to, but not before, a step increase in transmission of SARS-CoV-2. Download preprint here

Systematic methods for identifying relatively under-tested geographic regions and demographic groups may enable policymakers to regularly monitor and evaluate the shifting landscape of diagnostic testing. Download paper here

This publication presents and discusses how modeling was applied to simulate intervention per malaria risk strata in Mainland Tanzania. It complements several other publications that describe the advancements in malaria control planning processes in Tanzania Download paper here

A malaria transmission model, OpenMalaria, was used to simulate varying larviciding strategies and their impact on host-seeking mosquito densities, entomological inoculation rate (EIR) and malaria prevalence. Variations in coverage, duration, frequency, and timing of larviciding were simulated for three transmission intensities and four transmission seasonality profiles. Overall, larviciding would be more effective in settings with low and seasonal transmission, and at the beginning and during the peak densities of the target species populations. More operational data and improved calibration would enable models to become a practical tool to support malaria control programmes in developing larviciding strategies that account for the diversity of contexts. Download paper here

Systematic methods for identifying relatively under-tested geographic regions and demographic groups may enable policymakers to regularly monitor and evaluate the shifting landscape of diagnostic testing Download paper here

The Demographic and Health Surveys (DHS) Program is a critical data source for understanding subnational malaria prevalence and intervention coverage, which are used for parameterizing country-specific models of malaria transmission. However, data to estimate indicators at finer resolutions are limited, and surveys questions have a narrow scope. Examples from the Nigeria DHS are used to highlight gaps in the current survey design. Proposals are then made for additional questions and expansions to the DHS and Malaria Indicator Survey sampling strategy that would advance the data analyses and modelled estimates that inform national policy recommendationsDownload paper here

Pregnant women attending antenatal care (ANC) have been proposed as a pragmatic sentinel population for malaria surveillance. However, the representativeness of routine ANC malaria test-positivity and its relationship with prevalence in other population subgroups are yet to be investigated. Download paper here

This preprint demonstrates the ability of statistical data assimilation to identify the measurements required for accurate state and parameter estimation in an epidemiological model for the novel coronavirus disease COVID-19. Download paper here

This case study article describes available routine data and survey data at the district level in Tanzania and its use for sub-national stratification. Download paper here

This case study article describes the long-term use of modelling in close collaboration with the National Malaria Control Programme (NMCP) in Tanzania, the challenges encountered and lessons learned. Download paper here

The OpenMalaria model of malaria dynamics was calibrated for all 184 councils in mainland Tanzania using data from malaria indicator surveys, school parasitaemia surveys, entomological surveillance, and vector control deployment data. The methodology reported in this work is based on intensive interactions with the NMCP and provides a helpful tool for assessing the feasibility of country specific targets and for determining which intervention stratifications at sub-national level will have most impact. This country-led application could support strategic planning of malaria control in many other malaria endemic countries.

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A nationwide, school, malaria survey was implemented to assess the risk factors of malaria prevalence and bed net use among primary school children in mainland Tanzania. This allowed the mapping of malaria prevalence at council level and assessment of malaria risk factors among school children.

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