Table 1

Simplified trachoma grading proposed by the WHO.28 The signs were grouped according to whether they were acute or chronic

AbbreviationDenominationClinical findings
Acute trachomaTFTrachomatous inflammation—follicularPresence of five or more follicles at least 0.5 mm in diameter, in the upper tarsal conjunctiva
TITrachomatous inflammation—intenseThe tarsal conjunctiva appears red, rough and thickened. There are usually numerous follicles which may be partially or totally covered by the thickened conjunctiva
Cicatricial trachomaTSTrachomatous scarringThe presence of scarring in the tarsal conjunctiva. Scars are easily visible as white lines, bands, or sheets in the tarsal conjunctiva
TTTrachomatous trichiasisAt least one eyelash rubs on the eyeball. Evidence of recent removal of inturned eyelashes should also be graded as trichiasis
COCorneal opacityThe pupil margin is blurred viewed through the opacity. Such corneal opacities cause significant visual impairment (less than 6/18 or 0.3 vision), and therefore visual acuity should be measured if possible.