Community Ophthalmology and Preventive Care
Community ophthalmology and preventive care asks what you would do for a population rather than a patient: which diseases cause avoidable blindness, which interventions are cost-effective, and how programmes are monitored.
Core rules
- The main global causes of blindness are cataract, uncorrected refractive error, glaucoma, diabetic retinopathy, trachoma and onchocerciasis, with vitamin A deficiency in children.
- Trachoma: caused by Chlamydia trachomatis serovars A–C; the SAFE strategy - surgery for trichiasis, antibiotics (azithromycin), facial cleanliness and environmental improvement.
- Cataract is the leading cause of reversible blindness; the cataract surgical rate and cataract surgical coverage are the programme indicators, with outcome audit of postoperative acuity.
- Diabetic retinopathy screening: annual retinal photography for patients with diabetes; laser or anti-VEGF for sight-threatening disease.
- Vitamin A supplementation reduces childhood mortality and xerophthalmia; measles vaccination and promotion of breastfeeding are complementary.
- Avoidable blindness includes preventable causes (trachoma, onchocerciasis) and treatable causes (cataract, refractive error).
- Vision 2020 and the WHO global action plan provide the policy framework; integration into primary care improves coverage.
Worked example
A rural district has a trichiasis prevalence of 5% in adults over 40 and active trachoma in 20% of children. The programme should implement the full SAFE package: community-based trichiasis surgery for those with inturned lashes, mass azithromycin distribution, face-washing promotion and water and sanitation improvement. Surgery alone reduces individual suffering but does not interrupt transmission, so antibiotics and hygiene are needed in parallel. Impact is monitored by repeat prevalence surveys after three rounds.
Traps
Treating trachoma as a purely surgical problem, measuring cataract surgical volume without outcomes, and forgetting that refractive error is a major cause of avoidable visual impairment.