Longitudinal change in the serology of antibodies to Chlamydia trachomatis pgp3 in children residing in a trachoma area

Abstract

A serologic test for antibodies to chlamydial antigen pgp3 may be a useful tool for trachoma surveillance. However, little is known about the stability of antibody status over time, or factors associated with seroreversion/conversion. A cohort of 2,111 children ages 1–9 years in Tanzania were followed for one year in the absence of mass azithromycin. At baseline and follow-up, they were evaluated for trachoma, chlamydial infection, and antibodies to chlamydial antigen pgp3. At baseline, 31% of children were seropositive for pgp3 antibodies and 6.4% seroreverted to negative over one year. Of those seronegative, 9.8% seroconverted over the year. The seroreverters had lower baseline mean fluorescence intensity (MFI-BG) values compared to the seropositives who remained positive (Odds Ratio = 0.04 for every unit increase in log10MFI-BG, 95% CI = 0.02–0.09), and were more likely to live in communities with trachoma <5% (p < 0.008). While seroconversion was expected, seroreversion was unexpected. The low seroprevalence rate reported from low endemic areas may be due to seroreversion as well as lack of exposure.

Comprehensive Molecular Serology of HumanChlamydia trachomatisInfections by Peptide Enzyme-Linked Immunosorbent Assays

“…Seroepidemiology based on highly specific and sensitive assays can determine past exposure and measure the cumulative risk of C. trachomatis infection over time ( 4 – 7 ) and thus can help to minimize and control the burden of C. trachomatis infections in populations ( 71 ). The high performance of multipeptide ELISAs provides a powerful argument for their use in trachoma control ( 24 , 26 , 27 ) and in screening for sexually transmitted infections ( 21 , 25 , 28 ). Such multipeptide ELISAs will increase the effectiveness of trachoma surveillance programs, and they will enable earlier identification and treatment of young women with chlamydial infection in sexually transmitted disease (STD) screening, reducing a woman’s likelihood of experiencing highly consequential reproductive health complications.…”

Mixed Chlamydia trachomatis Peptide Antigens Provide a Specific and Sensitive Single-Well Colorimetric Enzyme-Linked Immunosorbent Assay for Detection of Human Anti-C. trachomatis Antibodies

“…Since these peptide antigens can be used for thousands of microtiter plates, the costs per assay would depend on the number of microtiter plates produced, the consumables per plate, and labor. Thus, we anticipate that such mixed peptide ELISAs will be highly labor-saving, economical, highly specific with adequate sensitivity, and suitable when small-volume samples are available such as sera eluted from dried blood spots ( 22 , 23 ).…”

“…Such tools can expedite ongoing efforts to minimize and control the burden of C. trachomatis infections in populations ( 46 ). The high performance of this multipeptide ELISA and the convenience of this method provide a strong argument for their use in trachoma control ( 22 , 23 , 47 – 49 ) and in screening for sexually transmitted infections ( 10 , 50 , 51 ). In conclusion, this highly specific and sensitive peptide ELISA will provide simple and yet improved C. trachomatis serology for epidemiological studies and will enhance accurate diagnosis of C. trachomatis infections, thereby mitigating sequelae from C. trachomatis infections ( 52 – 59 ).…”

Clinical signs of trachoma are prevalent among Solomon Islanders who have no persistent markers of prior infection with Chlamydia trachomatis

“…Although I agree with the overall conclusion that seroreversion cannot account for the differences in the data that were observed, the authors may want to consider looking at/adding the following reference which does support the presence of seroreversion: West et al (2018) 1 . …”