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bioRxiv · 10.1101/141135

Age-specific prevalence of anti-Pgp3 antibodies and severe conjunctival scarring in the Solomon Islands

Butcher, R.·Sokana, O.·Jack, K.·Martin, D.·Burton, M. J.·Solomon, A.·Mabey, D.·Roberts, C. h.
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Abstract

BackgroundTrachomatous trichiasis (TT) and ocular Chlamydia trachomatis (Ct) infection in the Solomon Islands are scarce, whereas trachomatous inflammation-follicular (TF) is prevalent.\n\nMethodsWe enrolled 1511 people aged [&ge;]1 year from randomly selected households in 13 villages in which >10% of the population had TF prior to a single round of azithromycin MDA undertaken six months previously. Blood was collected from people of all ages to be screened for anti-Pgp3 antibodies. Photographs were collected from people of all ages for analysis of scarring severity.\n\nResultsConjunctival scars were visible in 13.1% of photographs. Mild (p<0.0001) but not severe (p=0.149) scars increased in prevalence with age. Anti-Pgp3 antibody seroprevalence was 18% in 1-9 year olds, increased sharply around the age of sexual debut, and reached 69% in those over 25 years. Anti-Pgp3 seropositivity did not increase significantly between the ages of 1-9 years, and was not associated with scarring in children (p=0.472) or TF in children (p=0.581).\n\nConclusionsSigns of trachoma are common in the Solomon Islands but occur frequently in individuals who have no serological evidence of prior ocular infection with Ct. WHO recommendations for directing MDA provision based on signs alone may not be suitable in this context.

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Butcher, R., Sokana, O., Jack, K., Martin, D., Burton, M. J., Solomon, A., Mabey, D., Roberts, C. h.. 2017-05-30. Age-specific prevalence of anti-Pgp3 antibodies and severe conjunctival scarring in the Solomon Islands. https://doi.org/10.1101/141135

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