Screen and Treat Strategies for Malaria Elimination: A Review of Evidence
Passive case detection is the foundation of malaria surveillance and the primary mechanism for case identification in malaria control and elimination programs. However, passive case detection requires that patients seek care and rates of treatment-seeking behavior for fever in endemic countries are highly variable, often dependent on accessibility to health services. As transmission declines, a larger proportion of malaria infections are minimally symptomatic or asymptomatic, and most of these cases will not come to the attention of health facilities.
A variety of screen and treat (SAT) methods may be deployed by malaria programs to supplement routine case management through passive case detection. Proactive case detection (PACD) can be applied at mass or focal scale, typically in geographic areas or among demographic groups at high risk of malaria. Reactive case detection (RACD) is conducted in a targeted, reactive fashion at focal scale after identification of an individual case, usually detected passively.
SAT approaches allow programs to gather detailed epidemiological data on local malaria transmission and intervention coverage, essential for guiding the selection and targeting of additional interventions. Yet, SAT’s role in transmission reduction is unclear. In 2015, WHO’s Malaria Policy Advisory Committee recommended against the use of mass or focal SAT using standard diagnostic tests (microscopy and rapid diagnostic tests [RDT]) to reduce transmission. However, the 2017 WHO Malaria Elimination Framework details the roles and usefulness of PACD and RACD as surveillance tools, noting that both are important components of an elimination strategy.
In light of the uncertainty around the use of SAT for malaria elimination and growing evidence available in the literature, we conducted a systematic review to assess the utility and effectiveness of SAT for transmission reduction and surveillance. Our review included peer-reviewed literature as well as grey literature and unpublished experiences and perspectives from national malaria programs. The complete findings of the review are presented herein a detailed report, and we will publish a narrower quantitative analysis later in 2020.