The global burden of trichiasis in 2016

Area of Science:

• Ophthalmology
• Public Health
• Epidemiology

Background:

• Trichiasis is an eye condition caused by eyelashes touching the eye, potentially leading to blindness if uncorrected.
• Accurate epidemiological data on trichiasis prevalence and distribution are crucial for effective resource allocation in public health initiatives.
• Understanding the global burden of trichiasis is essential for targeted interventions and blindness prevention strategies.

Purpose of the Study:

• To obtain updated, district-level prevalence estimates for trichiasis in adults across 44 endemic and previously endemic countries.
• To provide a more accurate global burden estimate of trichiasis for the year 2016.
• To inform resource allocation and guide public health strategies for managing trichiasis.

Main Methods:

• Collected district-level trichiasis prevalence data from 44 countries, prioritizing the most recent available estimates.
• Applied age- and sex-standardized corrections to historical estimates where raw data were accessible.
• Utilized adjustment factors and expert assessments for districts lacking direct prevalence data to derive comprehensive estimates.

Main Results:

• The global burden of trichiasis in 2016 was estimated at 2.8 million cases (95% CI 1.1-5.2 million).
• Age- and sex-standardized data from 1,355 districts contributed significantly to the global total.
• Adjusted historical estimates and new expert assessments provided substantial case numbers, refining the overall burden calculation.

Conclusions:

• The 2016 trichiasis estimate is lower than previous figures, likely due to enhanced data quality and improved management services.
• Increased scale-up of trichiasis management services has contributed to the observed reduction in burden.
• Declining active trachoma prevalence is likely reducing the incidence of trichiasis, further impacting the overall numbers.