Research
Anopheles stephensi is an invasive malaria vector with unique ecological and biological traits that enable it to thrive in urban environments where native African vectors are limited. Its ability to develop in artificial water containers, tolerate high temperatures and dry conditions, persist year-round, and resist multiple classes of insecticides poses major challenges for malaria surveillance and control in rapidly urbanizing settings. These characteristics undermine traditional, climate-driven control strategies and demand new approaches tailored to urban transmission. Addressing this threat requires strengthened capacity in vector ecology, insecticide resistance, urban surveillance, and the development of innovative, locally adapted control tools. As a result, our training program has four areas of emphasis we will prioritize in our trainee's research programs that span vector ecology and control, malaria epidemiology, molecular genetics, and quantitative tools to support urban surveillance and control efforts.
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Scientific Themes and Mentors
The Urban Ecology and Behavior of Anopheles stephensi
This theme focuses on conducting mechanistic studies to understand how seasonality and urbanization shape the ecology and behavior of this invasive mosquito vector in Ethiopia. Trainees will examine how seasonal patterns, land cover, and land use influence mosquito presence and abundance, and how socio-economic factors and water storage practices affect human exposure. Research in this theme will emphasize developing rapid, data-driven methods to predict larval habitats and improve targeting of surveillance and control, alongside identifying efficient strategies for sampling adult mosquitoes in complex urban environments.
Possible Faculty Mentors: Dr. Solomon Yared (Jigjiga University, Africa), Dr. Gonzalo Vazquez-Prokopec (Emory University), Dr. Courtney Murdock and Laura Harrington (Cornell University), Dr. Michael Wimberly (University of Oklahoma), Dr. Yaw Afrane (University of Ghana), and Dr. Ajeet Mohanty (National Institute of Malaria Research - Indian Council of Medical Research)
Areas of Emphasis: Vector Ecology and Control, Modeling to Support Surveillance and Control
Research Highlight:
High-resolution satellite images can be used to locate construction pits that collect water and become breeding sites for mosquitoes. A. Examples of construction pits in Jigjiga, Ethiopia, where Anopheles stephensi mosquito larvae were found in March 2023 (shown by arrows) by mentors in our network. B. Google Earth Pro was used to mark all visible construction pits in the area (three pits are shown here with pins). C. A map showing the locations of 101 construction pits identified in November 2022—four months before field sampling—across a 4.3 km² rural-to-urban area centered on the main highway connecting Jigjiga to Somaliland, one of the region’s busiest routes. D. A map showing where construction pits are most concentrated. Warmer colors indicate higher numbers of pits per hectare, while dots show the exact pit locations.
Stars in panels C and D mark Jigjiga’s downtown area. Images in panels A-C were obtained from ESRI World Imagery, MAXAR, and the GIS User Community (Yared et al. 2023 Lancet Planetary Health).
Urban Malaria Transmission Dynamics and the Role of Anopheles stephensi
This theme focuses on understanding the relative contribution of Anopheles stephensi to malaria transmission in Africa and urban Ethiopia and identifying the environmental drivers of interannual variation in urban malaria risk. Trainees will develop forecasting models to predict transmission hotspots and ecological suitability across malaria-endemic cities, quantify seasonal and spatial patterns of parasite infection in An. stephensi, and evaluate whether relationships between key environmental factors and vectorial capacity differ across African populations and in comparison to the species’ native range in South Asia. This research equips trainees with integrative skills in epidemiology, ecology, and predictive modeling to address emerging urban malaria threats.
Possible Faculty Mentors: Dr. Solomon Yared (Jigjiga University, Africa); Drs. Courtney Murdock and Nicolas Buchon (Cornell University); Dr. Michael Wimberly (University of Oklahoma); Dr. Gonzalo Vazquez-Prokopec (Emory University); Drs. Ajeet Mohanty, Rajendra Baharia, and Praveen Bharti (National Institute of Malaria Research - Indian Council of Medical Research)
Areas of Emphasis: Malaria Epidemiology, Modeling to Support Surveillance and Control
Research Highlight:
These maps produced by mentors in our network and collaborators show the effects of temperature on the environmental suitability for malaria transmission by Anopheles stephensi in Africa relative to a common native Anopheles malaria vector. Models that use data specific to Anopheles stephensi (A) predict that many more areas will have more months of suitable temperatures for malaria transmission—shown in warmer colors—than models based on a native African mosquito species (B). This means the invasive mosquito can transmit malaria under a wider range of temperatures than previously expected, increasing the number of places potentially at risk (Villena et al. 2022 Ecology).
Genomics of Invasion and Insecticide Resistance
Research within this theme will apply whole-genome sequencing and molecular tools to understand the population structure, dispersal, and insecticide resistance of Anopheles stephensi across Africa. Trainees will investigate genetic variation at regional and local scales to disentangle the roles of human-mediated and natural dispersal in shaping gene flow and resistance mechanisms, and identify environmental and ecological factors that influence local population structure. The theme also emphasizes translating genomic discoveries into practice by developing and deploying targeted amplicon panels for insecticide resistance surveillance in support of National Malaria Control Program (NMCP) activities, building capacity at the interface of genomics and public health.
Possible Faculty Mentors: Dr. Solomon Yared (Jigjiga University, Africa); Dr. Gonzalo Vazquez-Prokopec (Emory University); Drs. Brian Lazzaro and Nicolas Buchon (Cornell University); Drs. Martin Donnelly, Eric Lucas, and Tristan Dennis (Liverpool School of Tropical Medicine); Dr. Yaw Afrane (University of Ghana); Dr. Praveen Bharti (National Institute of Malaria Research - Indian Council of Medical Research)
Areas of Emphasis: Molecular Genetics, Modeling to Support Surveillance and Control
Research Highlight:
A. Using complete DNA sequences from Anopheles stephensi mosquitoes, mentors in our network have found that populations from Saudi Arabia are genetically distinct from those in other parts of the mosquito’s native range and from Africa. Within Africa, mosquito populations also show genetic differences across broad geographic regions. B. Further analyses revealed clear genetic signatures of natural selection in genes linked to insecticide resistance, indicating that these mosquitoes are rapidly evolving ways to survive commonly used insecticides.
Evaluation and Implementation of Control Tools
Urban An. stephensi control in Africa requires interventions that are feasible to deploy at scale, effective across diverse artificial habitats, and robust to operational constraints (manpower, access, water insecurity, rapid construction, and heterogeneous risk). More importantly, control tools must account for An. stephensi’s biology and behavioral traits. While adult control tools can contribute in some settings, the dominance of artificial container habitats and construction-related water sources makes larval source management (LSM) and environmental management especially relevant. Moreover, expanding insecticide resistance threatens the long-term effectiveness of conventional approaches—so evaluation must integrate entomological impact, residual performance, resistance monitoring, and operational feasibility. This area of research will focus on the methods and approaches required to quantify the efficacy of vector control tools in laboratory, semi-field and field conditions. Research in this theme involves comparative field evaluations of larvicides across dominant urban habitat types to assess effectiveness and residual performance, and to design and implement cluster-randomized field trials to quantify intervention efficacy under An. stephensi invasion conditions. Research also evaluates environmental management strategies, including container modification and larvivorous fish, alongside novel insecticides such as residual formulations and spatial emanators, integrating biological efficacy with community acceptability. This area of research will also involve a strong social/community lens, which will mean trainees will work on surveys and other approaches of the social sciences to summarize knowledge and inform the design of novel control approaches.
Possible Faculty Mentors: Dr. Solomon Yared (Jigjiga University, Africa); Dr. Gonzalo Vazquez-Prokopec (Emory University); Drs. Martin Donnelly, Eric Lucas, and Tristan Dennis (Liverpool School of Tropical Medicine); Drs. Rajendra Baharia and Ajeet Mohanty (National Institute of Malaria Research - Indian Council of Medical Research), Dr. Yaw Afrane (University of Ghana), and Drs. Courtney Murdock and Laura Harrington (Cornell University).
Areas of Emphasis: Vector Ecology and Control, Molecular Genetics, Modeling to Support Surveillance and Control
