Prevalence of Chlamydia trachomatis-Specific Antibodies before and after Mass Drug Administration for Trachoma in Community-Wide Surveys of Four Communities in Nepal

Abstract

Abstract.The target end date for the global elimination of trachoma as a public health problem is 2020. As countries begin the process for submitting their dossier for the validation of elimination of trachoma as a public health problem, strategies for post-validation surveillance must be considered. Seroprevalence of antibodies against antigens from the causative bacteria Chlamydia trachomatis (Ct) in young children has been shown to reflect trachomatous inflammation–follicular (TF) rates in both endemic and previously endemic settings. However, none of these studies has directly compared age seroprevalence in the same communities before and after mass drug administration (MDA) for trachoma. Here we report a marked shift in age seroprevalence curves in four villages in Kapilvastu District, Nepal, before and after MDA. Clinical examinations were performed and blood was taken before (N = 659) and 5 years after (N = 646) MDA. Rates of TF decreased from 17.6% in ≤ 9-year-olds before MDA (N = 52) to 0% in ≤ 9-year-olds (N = 73) after MDA. Positive antibody responses to Ct in the entire population decreased from 82.1% pre-MDA to 35.8% post-MDA, whereas those among ≤ 9-year-olds decreased from 59.6% to 4.1%. These data show that the postintervention decrease in TF was reflected in a drop in anti-Ct antibody responses, suggesting that antibody responses could be useful indicators for post-validation surveillance.

Population-Based Prevalence of Chlamydia trachomatis Infection and Antibodies in Four Districts with Varying Levels of Trachoma Endemicity in Amhara, Ethiopia

“…5,6 In particular, antibodies against the C. trachomatis antigens Pgp3 and CT694 have been shown to be present in those infected with C. trachomatis, to increase with age in trachoma-endemic populations, and to be at low prevalence in populations receiving MDA with antibiotics. 5,[7][8][9][10] However, the programmatic role of these markers in trachoma control is still being determined. More data are needed from a range of settings to better understand the epidemiology of C. trachomatis-specific serological markers.…”

Urogenital chlamydia trachomatis treatment failure with azithromycin: A meta-analysis

“…Trials comparing azithromycin with doxycycline or other medications for the treatment of Chlamydiatrachomatis in women (cervicitis, urethritis, and rectal infection) or men (urethritis and rectal infection) were assessed. The inclusion criteria were: (1) Being a randomized clinical trial or a clinical trial; (2) Comparing treatment regimens of oral azithromycin (single- or multiple-dose regimens) with oral doxycycline (twice daily 100░mg for seven days) or other regimens; (3) Being a man or woman over the age of 12; (4) Assessment of microbial or clinical recovery during a follow-up period of 1–9 wk; and (5) Reporting treatment failure during the trial.…”

“…Chlamydia Trachomatis is an intracellular gram-negative bacterium and one of the most common pathogens transmitted through the genital tract in humans and causing urogenital infection. Chlamydia is one of the most common Sexually Transmitted Diseases (STDs) in the world, which has a higher prevalence among adolescents and women (1). According to the latest World Health Organization (WHO) reports, the reported prevalence of chlamydia has steadily increased over the last two decades, and 92 million new cases of chlamydia trachomatis infection occurred in 2009, reaching 101, 131, and 153 million in 2011, 2012, and 2015, respectively (2,3).…”

Determining seropositivity—A review of approaches to define population seroprevalence when using multiplex bead assays to assess burden of tropical diseases

“…It may also be unclear whether responses observed during a chronic infection ever revert to a seronegative state [35]. Therefore, using an indeterminate range or comparing the mean MFIs in these circumstances maybe more appropriate than enforcing a strict cut-off value [59,60].…”