The Walter Reed Project, Kisumu Field Station: Impact of Research on Malaria Policy, Management, and Prevention.

The Walter Reed Project is a collaboration between the Walter Reed Army Institute of Research of the United States Department of Defense and the Kenya Medical Research Institute. The Kisumu field station, comprising four campuses, has until recently been devoted primarily to research on malaria countermeasures. The Kombewa Clinical Research Center is dedicated to conducting regulated clinical trials of therapeutic and vaccine candidates in development.

Therapeutic response to artemisinin combination therapies among individuals with Plasmodium falciparum single infection vs mixed Plasmodium species infections: a retrospective posthoc analysis in Kisumu County, western Kenya.

Objectives: This study examined the treatment response of mixed vs single-species Plasmodium falciparum infections to artemisinin-based combination therapies (ACTs).

Methods: A total of 1211 blood samples collected on days 0, 7, 14, 21, 28, 35, and 42 from 173 individuals enrolled in two randomized ACT efficacy studies were tested for malaria using 18s ribosomal RNA-based real-time polymerase chain reaction. All recurrent parasitemia were characterized for Plasmodium species composition and time to reinfection during 42-day follow-up compared across ACTs.

Age-dependent antibody profiles to plasmodium antigens are differentially associated with two artemisinin combination therapy outcomes in high transmission setting.

The impact of pre-existing immunity on the efficacy of artemisinin combination therapy is largely unknown. We performed in-depth profiling of serological responses in a therapeutic efficacy study [comparing artesunate-mefloquine (ASMQ) and artemether-lumefantrine (AL)] using a proteomic microarray. Responses to over 200 antigens were significantly associated with ASMQ treatment outcome but not AL.

Malaria Transmission Dynamics in a High-Transmission Setting of Western Kenya and the Inadequate Treatment Response to Artemether-Lumefantrine in an Asymptomatic Population.

Background: Assessing the infectious reservoir is critical in malaria control and elimination strategies. We conducted a longitudinal epidemiological study in a high-malaria-burden region in Kenya to characterize transmission in an asymptomatic population.

Methods: 488 study participants encompassing all ages in 120 households within 30 clusters were followed for 1 year with monthly sampling.

Analysis of major genome loci underlying artemisinin resistance and pfmdr1 copy number in pre- and post-ACTs in western Kenya.

Genetic analysis of molecular markers is critical in tracking the emergence and/or spread of artemisinin resistant parasites. Clinical isolates collected in western Kenya pre- and post- introduction of artemisinin combination therapies (ACTs) were genotyped at SNP positions in regions of strong selection signatures on chromosome 13 and 14, as described in Southeast Asia (SEA). Twenty five SNPs were genotyped using Sequenom MassArray and pfmdr1 gene copy number by real-time PCR.