Comparison of platforms for testing antibodies to Chlamydia trachomatis antigens in the Democratic Republic of the Congo and Togo.

Gwyn, Sarah; Awoussi, Marcel S; Bakhtiari, Ana; Bronzan, Rachel N; Crowley, Kathryn; Harding-Esch, Emma M; Kassankogno, Yao; Kilangalanga, Janvier N; Makangila, Felix; Mupoyi, Sylvain; +10 more... Ngondi, Jeremiah; Ngoyi, Bonaventure; Palmer, Stephanie; Randall, Jessica M; Seim, Anders; Solomon, Anthony W; Stewart, Raymond; Togbey, Kwamy; Uvon, Pitchouna A; Martin, Diana L; (2021) Comparison of platforms for testing antibodies to Chlamydia trachomatis antigens in the Democratic Republic of the Congo and Togo. Scientific Reports, 11 (1). 7225-. DOI: https://doi.org/10.1038/s41598-021-86639-8

Abstract

Trachoma, caused by repeated ocular infection with Chlamydia trachomatis (Ct), is targeted for elimination as a public health problem. Serological testing for antibodies is promising for surveillance; determining useful thresholds will require collection of serological data from settings with different prevalence of the indicator trachomatous inflammation-follicular (TF). Dried blood spots were collected during trachoma mapping in two districts each of Togo and Democratic Republic of the Congo. Anti-Ct antibodies were detected by multiplex bead assay (MBA) and three different lateral flow assays (LFA) and seroprevalence and seroconversion rate (SCR) were determined. By most tests, the district with > 5% TF (the elimination threshold) had five-sixfold higher seroprevalence and tenfold higher SCR than districts with < 5% TF. The agreement between LFA and MBA was improved using a black latex developing reagent. These data show optimization of antibody tests against Ct to better differentiate districts above or below trachoma elimination thresholds.