Volume 82, Issue 3
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



It is unclear how the prevalence of clinically active trachoma correlates with the prevalence of ocular chlamydial infection at the community level. In 24 villages from a cluster-randomized clinical trial of mass azithromycin distributions in Ethiopia, the correlation between the prevalence of clinical activity (on examination) and chlamydial infection (by polymerase chain reaction) was moderately strong before mass antibiotic treatments (Pearson's correlation coefficient = 0.75, 95% confidence interval [CI] = 0.52–0.87), but decreased at each time point during four biannual treatments (at 24 months, = 0.15, 95% CI = −0.14–0.41). One year after the final treatment, the correlation coefficient had increased, but not to the pre-treatment level ( = 0.55, 95% CI = 0.30–0.73). In a region with hyperendemic trachoma, conjunctival examination was a useful indicator of the prevalence of chlamydial infection before treatments, less useful during mass treatments, but regained utility by one year after treatments had stopped.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...



  1. Resnikoff S, Pascolini D, Etya'ale D, Kocur I, Pararajasegaram R, Pokharel GP, Mariotti SP, , 2004. Global data on visual impairment in the year 2002. Bull World Health Organ 82: 844851. [Google Scholar]
  2. Sanford-Smith J, , 1997. Eye Diseases in Hot Climates. Oxford: Butterworth Heinemann, 105120. [Google Scholar]
  3. Miyashita N, Matsumoto A, Niki Y, Matsushima T, , 1996. Evaluation of the sensitivity and specificity of a ligase chain reaction test kit for the detection of Chlamydia trachomatis . J Clin Pathol 49: 515517.[Crossref] [Google Scholar]
  4. Bailey RL, Hampton TJ, Hayes LJ, Ward ME, Whittle HC, Mabey DC, , 1994. Polymerase chain reaction for the detection of ocular chlamydial infection in trachoma-endemic communities. J Infect Dis 170: 709712.[Crossref] [Google Scholar]
  5. Thylefors B, Dawson CR, Jones BR, West SK, Taylor HR, , 1987. A simple system for the assessment of trachoma and its complications. Bull World Health Organ 65: 477483. [Google Scholar]
  6. Miller K, Schmidt G, Melese M, Alemayehu W, Yi E, Cevallos V, Donnellan C, Olinger L, Fantaye D, Gaynor B, Whitcher JP, Lietman T, , 2004. How reliable is the clinical exam in detecting ocular chlamydial infection? Ophthalmic Epidemiol 11: 255262.[Crossref] [Google Scholar]
  7. Bobo LD, Novak N, Munoz B, Hsieh YH, Quinn TC, West S, , 1997. Severe disease in children with trachoma is associated with persistent Chlamydia trachomatis infection. J Infect Dis 176: 15241530.[Crossref] [Google Scholar]
  8. Bailey RL, Hayes L, Pickett M, Whittle HC, Ward ME, Mabey DC, , 1994. Molecular epidemiology of trachoma in a Gambian village. Br J Ophthalmol 78: 813817.[Crossref] [Google Scholar]
  9. Burton MJ, Holland MJ, Faal N, Aryee EA, Alexander ND, Bah M, Faal H, West SK, Foster A, Johnson GJ, Mabey DC, Bailey RL, , 2003. Which members of a community need antibiotics to control trachoma? Conjunctival Chlamydia trachomatis infection load in Gambian villages. Invest Ophthalmol Vis Sci 44: 42154222.[Crossref] [Google Scholar]
  10. Hayes LJ, Bailey RL, Mabey DC, Clarke IN, Pickett MA, Watt PJ, Ward ME, , 1992. Genotyping of Chlamydia trachomatis from a trachoma-endemic village in the Gambia by a nested polymerase chain reaction: identification of strain variants. J Infect Dis 166: 11731177.[Crossref] [Google Scholar]
  11. Grassly NC, Ward ME, Ferris S, Mabey DC, Bailey RL, , 2008. The natural history of trachoma infection and disease in a Gambian cohort with frequent follow-up. PLoS Negl Trop Dis 2: e341.[Crossref] [Google Scholar]
  12. Taylor HR, Siler JA, Mkocha HA, Munoz B, West S, , 1992. The natural history of endemic trachoma: a longitudinal study. Am J Trop Med Hyg 46: 552559. [Google Scholar]
  13. Holm SO, Jha HC, Bhatta RC, Chaudhary JS, Thapa BB, Davis D, Pokhrel RP, Yinghui M, Zegans M, Schachter J, Frick KD, Tapert L, Lietman TM, , 2001. Comparison of two azithromycin distribution strategies for controlling trachoma in Nepal. Bull World Health Organ 79: 194200. [Google Scholar]
  14. Solomon AW, Holland MJ, Alexander ND, Massae PA, Aguirre A, Natividad-Sancho A, Molina S, Safari S, Shao JF, Courtright P, Peeling RW, West SK, Bailey RL, Foster A, Mabey DC, , 2004. Mass treatment with single-dose azithromycin for trachoma. N Engl J Med 351: 19621971.[Crossref] [Google Scholar]
  15. Wright HR, Taylor HR, , 2005. Clinical examination and laboratory tests for estimation of trachoma prevalence in a remote setting: what are they really telling us? Lancet Infect Dis 5: 313320.[Crossref] [Google Scholar]
  16. Baral K, Osaki S, Shreshta B, Panta CR, Boulter A, Pang F, Cevallos V, Schachter J, Lietman T, , 1999. Reliability of clinical diagnosis in identifying infectious trachoma in a low-prevalence area of Nepal. Bull World Health Organ 77: 461466. [Google Scholar]
  17. Bird M, Dawson CR, Schachter JS, Miao Y, Shama A, Osman A, Bassem A, Lietman TM, , 2003. Does the diagnosis of trachoma adequately identify ocular chlamydial infection in trachoma-endemic areas? J Infect Dis 187: 16691673.[Crossref] [Google Scholar]
  18. Thein J, Zhao P, Liu H, Xu J, Jha H, Miao Y, Pizzarello L, Tapert L, Schachter J, Mabon M, Osaki-Holm S, Lietman T, Paxton A, , 2002. Does clinical diagnosis indicate ocular chlamydial infection in areas with a low prevalence of trachoma? Ophthalmic Epidemiol 9: 263269.[Crossref] [Google Scholar]
  19. Solomon A, Zondervan M, Kuper H, Buchan JC, Mabey DC, Foster A, , 2006. Trachoma Control: A Guide for Programme Managers. Geneva: World Health Organization. [Google Scholar]
  20. Altman D, , 1991. Practical Statistics for Medical Research. London: Chapman and Hall, 403409. [Google Scholar]
  21. Morre SA, van Dijk R, Meijer CJ, van den Brule AJ, Kjaer SK, Munk C, , 2001. Pooling cervical swabs for detection of Chlamydia trachomatis by PCR: sensitivity, dilution, inhibition, and cost-saving aspects. J Clin Microbiol 39: 23752376. [Google Scholar]
  22. Diamant J, Benis R, Schachter J, Moncada J, Pang F, Jha HC, Bhatta RC, Porco T, Lietman T, , 2001. Pooling of Chlamydia laboratory tests to determine the prevalence of ocular Chlamydia trachomatis infection. Ophthalmic Epidemiol 8: 109117.[Crossref] [Google Scholar]
  23. Melese M, Alemayehu W, Lakew T, Yi E, House J, Chidambaram JD, Zhou Z, Cevallos V, Ray K, Hong KC, Porco TC, Phan I, Zaidi A, Gaynor BD, Whitcher JP, Lietman TM, , 2008. Comparison of annual and biannual mass antibiotic administration for elimination of infectious trachoma. JAMA 299: 778784.[Crossref] [Google Scholar]
  24. Lakew T, House J, Hong KC, Yi E, Alemayehu W, Melese M, Zhou Z, Ray K, Chin S, Romero E, Keenan J, Whitcher JP, Gaynor BD, Lietman TM, , 2009. Reduction and return of infectious trachoma in severely affected communities in Ethiopia. PLoS Negl Trop Dis 3: e376.[Crossref] [Google Scholar]
  25. Bailey RL, Arullendran P, Whittle HC, Mabey DC, , 1993. Randomised controlled trial of single-dose azithromycin in treatment of trachoma. Lancet 342: 453456.[Crossref] [Google Scholar]
  26. Michel CE, Solomon AW, Magbanua JP, Massae PA, Huang L, Mosha J, West SK, Nadala EC, Bailey R, Wisniewski C, Mabey DC, Lee HH, , 2006. Field evaluation of a rapid point-of-care assay for targeting antibiotic treatment for trachoma control: a comparative study. Lancet 367: 15851590.[Crossref] [Google Scholar]
  27. Peeling RW, Toye B, Jessamine P, Gemmill I, , 1998. Pooling of urine specimens for PCR testing: a cost saving strategy for Chlamydia trachomatis control programmes. Sex Transm Infect 74: 6670.[Crossref] [Google Scholar]
  28. Shipitsyna E, Shalepo K, Savicheva A, Unemo M, Domeika M, , 2007. Pooling samples: the key to sensitive, specific and cost-effective genetic diagnosis of Chlamydia trachomatis in low-resource countries. Acta Derm Venereol 87: 140143.[Crossref] [Google Scholar]
  29. Melese M, Chidambaram JD, Alemayehu W, Lee DC, Yi EH, Cevallos V, Zhou Z, Donnellan C, Saidel M, Whitcher JP, Gaynor BD, Lietman TM, , 2004. Feasibility of eliminating ocular Chlamydia trachomatis with repeat mass antibiotic treatments. JAMA 292: 721725.[Crossref] [Google Scholar]

Data & Media loading...

  • Received : 08 Jun 2009
  • Accepted : 16 Nov 2009
  • Published online : 05 Mar 2010

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error