Lead Investigators of the Malaria Reservoir Study (MRS) disseminated results of the study showing how the reservoir of malaria infection responded to the sequential implementation of National Malaria Elimination Programme (NMEP) interventions in the Bongo District of the Upper East Region of northern Ghana.
The MRS which was initiated in June 2012 at the Bongo District through is a collaborative research project involving renowned researchers, Dr. Abraham Oduro and Dr. Patrick Ansah from the Navrongo Health Research Centre (NHRC) Ghana, Professor Kwadwo Koram from the Noguchi Memorial Institute for Medical Research, Professor Karen Day from the University of Melbourne, Australia, and Professor Mercedes Pascual the University of Chicago University of New York, USA.
The MRS is funded by the Fogarty International Center and the National Institute of Allergy and Infectious Diseases at the National Institutes of Health through the joint NIH-NSF-NIFA Ecology and Evolution of Infectious Diseases program.
The MRS is among the few studies in sub-Saharan Africa that have specifically examined how the asymptomatic Plasmodium falciparum reservoir termed as the “reservoir of infection” in the general population, across all age groups, responds to the phased implementation of major malaria control interventions.
On the 10th and 15th of May 2024, Professor Karen Day, Dr. Patrick Ansah, Dr. Kathryn Tiedje, Dr. Victor Asoala and Mr. Oscar Bangre disseminated findings on behalf of the MRS team to key stakeholders at the Upper East Regional Health Directorate and the Bongo District Health Directorate, respectively. The participants at both the Regional and the Bongo District Health Directorate forums included heads of the District Health Management Teams (DHMT), Sub-district heads, representatives from the district assemblies, departments, and agencies as well as community and opinion leaders, traditional leaders, queen-mothers, and assembly men and women.
In their statements, both Dr. Samuel Boakye-Boateng the Regional Director of Health Services and Ms. Estella Abazesi the District Director of Health Services for Bongo expressed their appreciation for the efforts of the MRS research team in monitoring the impacts of NMEP interventions on malaria prevalence and transmission in Bongo District over the last decade. They also stated that the indigenes have reported a remarkable reduction in malaria cases at Health Centers as a result of the introduction of these various NMEP interventions. Both Dr. Boakye-Boateng and Ms. Abazesi urged the researchers to continue to conduct policy-informing research which will facilitate further interventions to eliminate malaria in Bongo and the Upper East Region.
In addition to these presentations with local stakeholders, meetings were also undertaken with Mr. Samuel Asiedu Agyei, Executive Director of the AngloGold Ashanti Malaria Control Programme (AGAMal), on the 14th of May 2024 and Dr. Nana Yaw Peprah, Deputy Program Manager of the NMEP, and the NMEP team in Accra on the 20th of May 2024.
These disseminations lead by Professor Day, focused on the key findings from this decade long study that has explored through cross-sectional surveys of 2,000 participants per survey, the impact of key interventions on the P. falciparum reservoir of infection in the district from 2012 to 2023.
During the engagements Professor Day and Dr. Ansah, provided critical insights on malaria transmission, interventions, and control strategies aimed at addressing the ongoing challenge of malaria in the Bongo District. The Investigators also acknowledged the importance of the continued support from the Bongo District community, the local health authorities, AGAMal, and the NMEP, calling for continued collaboration to advance towards malaria elimination in the district, region, and country.
Professor Karen P. Day
Summary of the Research Findings from the MRS
During the presentations, it was revealed that the sequential malaria control interventions that have been rolled out in the Bongo District have led to shifts in the local malaria transmission patterns. The main interventions that have been deployed across the Bongo District include the distribution of Long-Lasting Insecticidal Nets (LLINs), Indoor Residual Spraying (IRS), and Seasonal Malaria Chemoprevention (SMC).
Delving into each intervention, the Investigators showed that reported LLIN usage (distributed in 2012, 2016, and 2021) remained high 85% in each survey between 2012 and 2022. The LLINs have been and remain an essential component of NMEP’s control strategy aimed at reducing malaria transmission by disrupting new infections.
The IRS, which involved the spraying of homes with non-pyrethroid insecticides to reduce mosquito populations, was another crucial intervention. This intervention was implemented across the Bongo District from 2013 to early 2015 by AGAMal. The data collected revealed that following IRS, not only did transmission intensity decline by more than 90%, but that P. falciparum prevalence decreased by 40 to 50% across all ages.
However, in 2017, after IRS was discontinued, there was a rebound in the P. falciparum reservoir that was observed in all ages, except for children under 5 years age who were receiving SMC. This MRS also provided evidence that the SMC intervention, which specifically targets children between 3-59 months (less than 5 years), has been successful in keeping malaria prevalence lower among this target age group. Importantly this rebound in prevalence in the Bongo District following the discontinuation of IRS is a major concern and showed that the significant gains made towards eliminating malaria were quickly reversed once IRS was stopped.
To investigate the impact of these NMEP interventions in the Bongo District, the MRS used an integrated approach, combining entomological, parasitological, and molecular surveillance methods to monitor the P. falciparum reservoir. The MRS also highlighted the urgent need to integrate malaria control interventions to prevent rebounds in the reservoir of infection, while also emphasizing the importance of interventions that target both the mosquito vector and the human host.
Although the combination of LLINs, IRS, and SMC has proven to be highly effective in the Bongo District, the discontinuation of any of these NMEP interventions risks undoing years of progress. For malaria elimination to be a reality for Ghana, a sustained approach must be taken. This policy shaping research continues to position Bongo District as a key player in Ghana’s broader research efforts to eliminate malaria and could serve as a framework for other high-transmission areas in sub-Saharan Africa.
For additional information on the publications from the MRS please see: https://linktr.ee/MRS_BongoGhana