May 2005
Volume 46, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2005
A Rapid Field–Based Assay for Ocular C Trachomatis Infection for Use in Trachoma Control Programs: Rationale and Requirements
Author Affiliations & Notes
  • A.W. Solomon
    Clinical Research Unit,
    London School of Hygiene & Tropical Medicine, London, United Kingdom
  • N.D. E. Alexander
    Infectious Disease Epidemiology Unit,
    London School of Hygiene & Tropical Medicine, London, United Kingdom
  • M.J. Burton
    Clinical Research Unit,
    London School of Hygiene & Tropical Medicine, London, United Kingdom
  • B. Munoz
    Dana Center for Preventive Ophthalmology, Johns Hopkins University, Baltimore, MD
  • R.L. Bailey
    Clinical Research Unit,
    London School of Hygiene & Tropical Medicine, London, United Kingdom
  • S.K. West
    Dana Center for Preventive Ophthalmology, Johns Hopkins University, Baltimore, MD
  • A. Foster
    Clinical Research Unit,
    London School of Hygiene & Tropical Medicine, London, United Kingdom
  • D.C. W. Mabey
    Clinical Research Unit,
    London School of Hygiene & Tropical Medicine, London, United Kingdom
  • WT/BWF Trachoma Study Group
    London School of Hygiene & Tropical Medicine, London, United Kingdom
  • Footnotes
    Commercial Relationships  A.W. Solomon, None; N.D.E. Alexander, None; M.J. Burton, None; B. Munoz, None; R.L. Bailey, None; S.K. West, None; A. Foster, None; D.C.W. Mabey, None.
  • Footnotes
    Support  Wellcome Trust/Burroughs Wellcome Fund, Edna McConnell Clark, International Trachoma Initiative, MRC
Investigative Ophthalmology & Visual Science May 2005, Vol.46, 5020. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      A.W. Solomon, N.D. E. Alexander, M.J. Burton, B. Munoz, R.L. Bailey, S.K. West, A. Foster, D.C. W. Mabey, WT/BWF Trachoma Study Group; A Rapid Field–Based Assay for Ocular C Trachomatis Infection for Use in Trachoma Control Programs: Rationale and Requirements . Invest. Ophthalmol. Vis. Sci. 2005;46(13):5020.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Abstract: : Purpose: Trachoma is caused by Chlamydia trachomatis; antibiotics are part of the control strategy. However, the relationship between infection and clinical signs is imperfect, particularly in low prevalence settings and after one or more rounds of antibiotics. Existing tests for infection are unsuitable for use by trachoma control programs. A rapid, reliable, cheap test for ocular C. trachomatis that could be used in the field to estimate community prevalence of infection would ensure that antibiotics are given to communities that need them most. Methods: From each of three datasets from trachoma–endemic communities in Tanzania and The Gambia, we repeatedly (10,000 times) simulated sampling 50 children aged 1–9. For each sample, the decision that would be made to treat or not treat the community based on the prevalence of TF in the sample was compared with the decision that would be made based on the community prevalence of ocular C. trachomatis infection, by PCR. For each child in each sample we also simulated a result for a putative C. trachomatis dipstick test, based on assumed values for its sensitivity and specificity. As for TF, we compared treatment decisions based on dipstick to those based on PCR. Results: Receiver operating characteristic plots (showing the trade–off between sensitivity and specificity of the method at decision–to–treat–the–community level) demonstrate that a dipstick test that was 97.5% specific and only 80% sensitive (at individual level) would be an advance over using TF. Conclusions: These performance characteristics are achievable with currently available technology. The dipstick could be used by the same or lower cadre of staff as those who currently undertake surveys of TF prevalence, and would not be subject to the same degree of observer bias. Further research to develop dipsticks for use by trachoma control programs is warranted.

Keywords: trachoma • detection • clinical (human) or epidemiologic studies: systems/equipment/techniques 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×