Malaria is a major health challenge in sub-Saharan Africa, where it kills hundreds of thousands of people every year. The western Kenya highlands, a region that was historically free of malaria, has seen a significant increase in transmission in recent years, partly due to climate variability caused by events such as El Niño.
Surveillance and monitoring are essential for early detection and management of malaria transmission surges. However, traditional surveillance tools may become insensitive when transmission rates are below a certain threshold.
A new study published in the Malaria Journal tested a rapid diagnostic kit comprising Plasmodium falciparum circumsporozoite surface protein and merozoite surface protein antibodies in humans for early detection of transmission surges in the western Kenya highlands during an El Niño event (October 2009-February 2010).
The study found that the antibody-based assay had much earlier transmission detection ability than the sporozoite-based assay. An upsurge in antibody levels was first observed in October 2009, and Plasmodium falciparum sporozoites were detected in December 2009 at Iguhu village and February 2010 at Emutete. No sporozoites were detected in Marani and Fort Ternan throughout the eight-month study period.
The changing malaria transmission rates in the western Kenya highlands will lead to more unstable transmission, decreased immunity, and a high vulnerability to epidemics unless surveillance tools are improved and effective vector control is sustained. The new rapid diagnostic kit can help improve surveillance and control of malaria in the region.
The study also found a rearrangement of the sibling species of the Anopheles gambiae s.l complex, possibly as an adaptation to insecticide interventions and climate change.
In conclusion, the study highlights the importance of surveillance and monitoring in the fight against malaria and the potential of new tools such as the rapid diagnostic kit for early detection of transmission surges. The findings can inform the development of effective strategies for malaria control and prevention in the western Kenya highlands.
Read the full paper here: