The World Health Organization Recommendations for Trachoma Surveillance, Experience in Nepal and Added Benefit of Testing for Antibodies to <i>Chlamydia trachomatis</i> pgp3 Protein: NESTS Study

<div><p>Background</p><p>The World Health Organization (WHO) now requires a second surveillance survey for trachoma after an impact assessment has found follicular trachoma (TF) <5% to determine if re-emergence has occurred. <i>Using</i> new WHO guidelines, we undertook surveillance surveys, and determined the prevalence of infection and antibody positivity, in two districts in Nepal.</p><p>Methods</p><p>20 clusters were randomly selected within each district, 15 were randomly selected for antibody testing. In each cluster, we randomly selected 50 children ages 1–9 years and 100 adults ≥15 years. TF and trachomatous trichiasis (TT) were evaluated. Conjunctival swabs to test for chlamydial infection using GenXpert platform were obtained, and dried blood spots were collected to test for antibodies to <i>Chlamydia Trachomatis</i> pgp3 using the Luminex platform.</p><p>Findings</p><p>3 cases of TF were found in the two districts, and one case of infection. Pgp3 antibody positivity was 2·4% (95% confidence interval: 1·4%, 3·7%), and did not increase with age (<i>P</i> = 0.24). No clustering of antibody positivity within communities was found. TT prevalence was <1/1,000 population.</p><p>Interpretation</p><p>The surveillance surveys, as proposed by WHO, showed no evidence for re-emergence of trachoma in two districts of Nepal. The low level and no significant increase by age in seroprevalence of antibodies to <i>C trachomatis</i> pgp3 antigen deserve further investigation as a marker of interruption of transmission.</p></div

LF antigenemia in pre-TAS survey based on MDA participation.

<p>LF antigenemia in pre-TAS survey based on MDA participation.</p

Trichiasis and TT in adults ≥15 years old stratified by district.

<p>Trichiasis and TT in adults ≥15 years old stratified by district.</p

Summary of results from TAS.

<p>Summary of results from TAS.</p

Number of clusters per district with zero, one, or more than one child antibody positive.

<p>Number of clusters per district with zero, one, or more than one child antibody positive.</p

Percent of antibody positivity stratified by age and district.

<p>Percent of antibody positivity stratified by age and district.</p

Log MFI–BG value for antibody to pgp3, distributed by age.

<p>The red line corresponds to the cut-off value for positivity. Of the 30 clusters studied, 17 (57%) had no antibody positivity, 8 (27%) had just one child positive, and 5 (16%) had two to three children antibody positive. No cluster had more than 3 children who were antibody positive (<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0005003#pntd.0005003.g002" target="_blank">Fig 2</a>). There was no evidence that children who were antibody positive clustered within community (ICC 95% Confidence interval: 0·05 (-0·21, 0·32), <i>P</i> = 0·68).</p

Controlling Neglected Tropical Diseases (NTDs) in Haiti: Implementation Strategies and Evidence of Their Success

<div><p>Lymphatic filariasis (LF) and soil-transmitted helminths (STH) have been targeted since 2000 in Haiti, with a strong mass drug administration (MDA) program led by the Ministry of Public Health and Population and its collaborating international partners. By 2012, Haiti’s neglected tropical disease (NTD) program had reached full national scale, and with such consistently good epidemiological coverage that it is now able to stop treatment for LF throughout almost all of the country. Essential to this success have been in the detail of how MDAs were implemented. These key programmatic elements included ensuring strong community awareness through an evidence-based, multi-channel communication and education campaign facilitated by voluntary drug distributors; strengthening community trust of the drug distributors by ensuring that respected community members were recruited and received appropriate training, supervision, identification, and motivation; enforcing a “directly observed treatment” strategy; providing easy access to treatment though numerous distribution posts and a strong drug supply chain; and ensuring quality data collection that was used to guide and inform MDA strategies. The evidence that these strategies were effective lies in both the high treatment coverage obtained– 100% geographical coverage reached in 2012, with almost all districts consistently achieving well above the epidemiological coverage targets of 65% for LF and 75% for STH—and the significant reduction in burden of infection– 45 communes having reached the target threshold for stopping treatment for LF. By taking advantage of sustained international financial and technical support, especially during the past eight years, Haiti’s very successful MDA campaign resulted in steady progress toward LF elimination and development of a strong foundation for ongoing STH control. These efforts, as described, have not only helped establish the global portfolio of “best practices” for NTD control but also are poised to help solve two of the most important future NTD challenges—how to maintain control of STH infections after the community-based LF “treatment platform” ceases and how to ensure appropriate morbidity management for patients currently suffering from lymphatic filarial disease.</p></div

Number of people treated and cumulative number of treatments given by program year.

<p>Number of people treated and cumulative number of treatments given by program year.</p

Cascade training.

<p>Cascade training.</p