To improve malaria surveillance and achieve elimination, the Zambian National Malaria Elimination Program implemented a reactive test-and-treat program in Southern Province in 2013 in which individuals with rapid diagnostic test (RDT)–confirmed malaria are followed-up at their home within 1 week of diagnosis. Individuals present at the index case household and those residing within 140 m of the index case are tested with an RDT and treated with artemether–lumefantrine if positive. This study evaluated the efficiency of this reactive test-and-treat strategy by characterizing infected individuals missed by the RDT and the current screening radius. The radius was expanded to 250 m, and a quantitative polymerase chain reaction (qPCR) test was performed on dried blood spot specimens. From January 2015 through March 2016, 145 index cases were identified at health centers and health posts. A total of 3,333 individuals residing in 525 households were screened. Excluding index cases, the parasite prevalence was 1.1% by RDT (33 positives of 3,016 participants) and 2.4% by qPCR (73 positives of 3,016 participants). Of the qPCR-positive cases, 62% of 73 individuals tested negative by RDT. Approximately half of the infected individuals resided within the index case household (58% of RDT-positive individuals and 48% of qPCR-positive individuals). The low sensitivity of the RDT and the high proportion of secondary cases within the index case household decreased the efficiency of this reactive test-and-treat strategy. Reactive focal drug administration in index case households would be a more efficient approach to treating infected individuals associated with a symptomatic case.
Bibliographical noteFunding Information:
Financial support: This work was supported by the Johns Hopkins Malaria Research Institute, the Bloomberg Philanthropies, and the Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases as part of the International Centers of Excellence for Malaria Research (U19AI089680).
We thank the members of the community for their volunteer participation in the surveys and the Macha Research Trust field team for conducting the surveys, without whom this research would not have been possible. This work was supported by the Johns Hopkins Malaria Research Institute, the Bloomberg Philanthropies, and the Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases as part of the International Centers of Excellence for Malaria Research (U19AI089680).
Copyright © 2018 by The American Society of Tropical Medicine and Hygiene.