Table 1

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

	Abbreviation	Denomination	Clinical findings
Acute trachoma	TF	Trachomatous inflammation—follicular	Presence of five or more follicles at least 0.5 mm in diameter, in the upper tarsal conjunctiva
	TI	Trachomatous inflammation—intense	The tarsal conjunctiva appears red, rough and thickened. There are usually numerous follicles which may be partially or totally covered by the thickened conjunctiva
Cicatricial trachoma	TS	Trachomatous scarring	The presence of scarring in the tarsal conjunctiva. Scars are easily visible as white lines, bands, or sheets in the tarsal conjunctiva
	TT	Trachomatous trichiasis	At least one eyelash rubs on the eyeball. Evidence of recent removal of inturned eyelashes should also be graded as trichiasis
	CO	Corneal opacity	The 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.