Trachoma is the world's leading cause of preventable blindness. In 1997 the World Health Organization launched an initiative on trachoma control based on the 'SAFE' strategy (surgery, antibiotics, facial cleanliness and environmental improvement).
The aim of this review is to assess the evidence supporting the antibiotic arm of the SAFE strategy by assessing the effects of antibiotics on both active trachoma (primary objective) and on Chlamydia trachomatis infection of the conjunctiva (secondary objective).
We searched the Cochrane Central Register of Controlled Register - CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library Issue 4, 2004), MEDLINE (1966 to April 2004), and EMBASE (1980 to May 2004). We used the Science Citation Index to look for articles that cited the included studies. We searched the reference lists of identified articles and we contacted authors and experts for details of further relevant studies.
We included only randomised trials that satisfied either of two criteria: (a) trials in which topical or oral administration of an antibiotic was compared to placebo or no treatment in people with trachoma, (b) trials in which a topical antibiotic was compared with an oral antibiotic in people with trachoma. A subdivision of particular interest was of trials in which topical tetracycline/chlortetracycline was compared with oral azithromycin, as these are the two World Health Organization recommended treatments.
Data collection and analysis
Two reviewers independently assessed trial quality and extracted data. We contacted investigators for missing data.
We found 15 studies that randomised a total of 8678 participants. For both outcomes (active trachoma and laboratory evidence of infection) the results of the chi squared tests suggested that there was significant statistical heterogeneity among the trials. There was also marked clinical heterogeneity. No summary statistics were calculated and we therefore present a narrative summary of the results. For the comparisons of oral or topical antibiotic against placebo/no treatment, the data are consistent with there being no effect of antibiotics but are suggestive of a lowering of the point prevalence of relative risk of both active disease and laboratory evidence of infection at three and 12 months after treatment. For the comparison of oral against topical antibiotics the results suggest that oral treatment is neither more nor less effective than topical treatment.
There is some evidence that antibiotics reduce active trachoma but results are not consistent and cannot be pooled.