Longitudinal Malaria Surveillance in Kenya

A longitudinal cohort of households across three villages (Kinesamo, Maruti, and Sitabicha) in Bungoma county, Kenya was established in June 2017 and followed until July 2018. The three villages were selected based on their high malaria prevalence in a previous cross-sectional study^{61 (link)}. All household members in participating households over the age of 1 year were offered enrollment. Sample collection details have been reported⁶² . For each participant, demographic and behavioral questionnaires were administered and dried blood spot (DBS) samples were collected every month. The DBS were tested for P. falciparum parasites using real-time PCR post hoc (see below), and therefore parasites detected in asymptomatic people were not treated. Participants contacted the study team at any time when experiencing symptoms consistent with malaria, at which time they were tested for malaria using a rapid diagnostic test (RDT) (Carestart © Malaria HRP2 Pf from Accessbio)⁶³ and, if positive, treated with Artemether-Lumefantrine. DBS were also collected at the time of RDT testing. One morning each week, indoor resting mosquitoes were collected from participant households using vacuum aspiration with Prokopacks⁶⁴ . From these collections, female Anopheles mosquitoes were identified morphologically and transected to separate the abdomen from the head and thorax.