Eliminating the Reservoir of Chronic Malaria Infections in Ghana: A Research Challenge

Dr Kathryn Tiedje, a malaria epidemiologist, visits Ghana several times per year to coordinate field research activities on behalf of the Day group and their collaborators from the University of Michigan (USA), Noguchi Memorial Institute for Medical Research (Ghana) and Navrongo Health Research Centre (Ghana).

Funded by the National Institutes of Health and the Fogarty International Centre in the USA, their investigation aims to eliminate Plasmodium falciparum, a parasite that causes over half a million deaths annually, with the majority of this burden in Sub-Saharan Africa. The grant supports a multidisciplinary team including malaria geneticists, bioinformaticians, mathematical biologists, clinical/molecular epidemiologists and entomologists. They are interested in better understanding the complexities of malaria transmission in the context of the parasite’s genetic diversity in chronic carriers of infection. These chronic carriers constitute the reservoir of infection that continually fuels the spread of malaria to mosquitoes making it difficult to interrupt transmission and eliminate malaria.

The project utilises a longitudinal cohort study design to determine the impacts of seasonality and malaria control programs on P.falciparum genetic diversity. The field research is being conducted in the Upper East Region in Ghana where a population of 100,000 residents are receiving a series of malaria control interventions, including insecticide treated bednets, indoor residual spraying (IRS) and Artemisinin combination therapy.

“We have recruited a cohort of 2000 participants and have mapped where they live, determined their socio-economic status, bed net usage and health status, thanks to the Navrongo Health Research Centre who have fostered ongoing relationships with the community. This relationship is very important for the success of the project. Not only will scientific information be gained but it will help to bring resources to the community to control malaria and strengthen health systems in the region,” Dr Tiedje said.

Over the course of this five-year project, IRS will be rolled out through Global Fund support. By collecting data at seasonal time points, the research team has a unique opportunity to assess the diversity of the parasite before, during and after the IRS. By analysing the baseline data, the team found that all age groups are carrying chronic malaria infections. They are now investigating the spatial and temporal genetic structure of the malaria parasite population in these chronic carriers in response to interventions using genomics and bioinformatics. With this study design, their goal is to create a conceptual shift in malaria control practices, as current public health strategies do not take parasite diversity into consideration when they are monitored and evaluated.

“Our team’s mission is to find new solutions for this chronic illness. We need to consider traditional methods of control, but we must also try to understand the effects of interventions on the parasite in order to finally eradicate it globally,” said Dr Tiedje.

Malaria in Ghana

Infectious Diseases