Chlamydial infection during trachoma monitoring: are the most difficult‐to‐reach children more likely to be infected?

• Published in: Tropical medicine & international health 2012-03, Vol.17 (3), p.392-396
• Main Authors: Keenan, Jeremy D., Moncada, J., Gebre, T., Ayele, B., Chen, M. C., Yu, S. N., Emerson, P. M., Stoller, N. E., McCulloch, C. E., Gaynor, B. D., Schachter, J.
• Format: Article
• Language: English
• Subjects: ARN; Azithromycin - therapeutic use; Bacterial diseases; Bacterial diseases of the eye and orbit; biais d’échantillonnage; Biological and medical sciences; Chlamydia; Chlamydia trachomatis - genetics; clamidia; Conjunctiva - microbiology; Delivery of Health Care; enfermedades olvidadas; General aspects; Health Services Accessibility; Human bacterial diseases; Humans; Infectious diseases; maladies négligées; Medical sciences; neglected diseases; Odds Ratio; Population Surveillance; Residence Characteristics; RNA; sampling bias; sesgo de muestreo; Trachoma - diagnosis; Trachoma - drug therapy; Trachoma - epidemiology; Trachoma - microbiology
• ISSN: 1360-2276; 1365-3156
• DOI: 10.1111/j.1365-3156.2011.02919.x

Objectives  During mass antibiotic distributions for trachoma, certain individuals are difficult to locate and go untreated. These untreated individuals may serve as a source of community reinfection. The importance of this difficult‐to‐locate, untreated population is unclear. We sought to determine whether individuals who are difficult to locate were more likely to be infected with ocular chlamydia than those who were easier to locate. Methods  We monitored 12 Ethiopian communities 1 year after a third annual mass azithromycin treatment for trachoma. Conjunctival swabbing for chlamydial RNA was performed in a random sample of children from each community. If insufficient numbers of children were enrolled on the first monitoring day, we returned on subsequent days. Results  Of the 12 communities, 10 required more than one monitoring day. On average, 16.1% (95% CI 7.9–30.0) of children were enrolled after the initial day. Evidence of chlamydia was found in 7.1% (95% CI 2.7–17.4) of 0‐ to 9‐year‐old children. No ocular swabs collected after the initial day were positive for chlamydial RNA. Children examined after the initial monitoring day were significantly less likely to have ocular chlamydial infection than children seen on the initial day; Mantel–Haenszel common OR = 0 (95% CI 0–0.77). Conclusions  In a setting of repeated annual mass azithromycin treatments, after approximately 80% of individuals have been located in a community, extra efforts to find absent individuals may not yield significantly more cases of ocular chlamydia. Objectifs:  Lors de la distribution en masse d’antibiotiques pour le trachome, certains individus sont difficiles à localiser et ne sont pas traités. Ces personnes non traitées peuvent servir de source de réinfection pour la communauté. L’importance de ces cas difficiles à localiser et non traités n’est pas claire. Nous avons cherchéà déterminer si les individus difficiles à localiser étaient plus susceptibles d’avoir une infection oculaire par Chlamydia par rapport à ceux qui étaient plus faciles à localiser. Méthodes:  Nous avons surveillé 12 communautés éthiopiennes 1 an après un troisième traitement de masse annuel par l’azithromycine pour le trachome. Un écouvillonnage conjonctival pour la détection de l’ARN du Chlamydia a été réalisé sur un échantillon aléatoire d’enfants dans chaque communauté. Si au cours de la journée initiale de surveillance un nombre insuffisant d’enfants étaient recrutés, le recrutement était poursui