WHO Alliance for the Global Elimination of Trachoma: progress report on elimination of trachoma, 2021

Overview

This report summarizes work conducted during 2021 to apply the SAFE strategy against trachoma. It includes estimates of the global population at risk of trachoma blindness based on district-by-district data submitted to WHO by national programmes. It is inherently complex to summarize the underlying epidemiological situation in this way, because for any district up to 3 estimates of prevalence may be valid at different times within a calendar year. If reported in isolation, there is a risk that TF prevalence estimates from impact surveys done after (but in the same calendar year as) antibiotic treatment might (i) be interpreted as indicating that treatment was unjustified and (ii) result in division-by zero errors in calculations of antibiotic coverage against need. To avoid these problems, the highest TF prevalence estimate in the calendar year (regardless of the date in the year on which that estimate was valid) was used to generate a rolling peak prevalence estimate for 1 January–31 December 2021 ; these figures were the denominators for calculating intervention coverage. To also provide the most up-to-date snapshot of progress towards global elimination of trachoma as a public health problem, summaries based on district level prevalence estimates held in the GET2020 database as of 1 June 2022 are also included (Table 1). The point-prevalence snapshot for 1 June 2022 can be compared with that of 21 June 2021.