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Prevalence and Pattern of Refractive Errors Among Yanomami Indigenous People in the Brazilian Amazon: A
Maria Christina Chagas Ferreira1, Marcos Antonio Pellegrini1, Bianca Jorge Sequeira1
1Universidade Federal de Roraima, PROCISA, Boa Vista, Roraima, Brazil.
Background:
Refractive errors are the leading cause of preventable visual impairment worldwide, yet data from isolated Indigenous populations remain virtually absent from the global literature. The Yanomami, one of the largest Indigenous peoples in the Americas with recent and limited contact with non-Indigenous society, have no prior epidemiological data on refractive errors METHODS: A cross-sectional observational study was conducted in 2024 at the Yanomami Indigenous Health House, Boa Vista, Roraima, Brazil. A total of 158 self-identified Yanomami individuals aged 5 years or older were examined by an ophthalmologist. Refractive status was classified according to International Myopia Institute criteria.
Results:
Emmetropia was observed in 67.7% of participants, declining markedly with age from 100% in children aged 5 to 9 years to 38.6% in those aged 40 to 59 years. Myopia was present in 16.5%, all low myopia, absent in children under 10 years, with no high myopia identified. Astigmatism affected 24.1% and hyperopia 12.7%. Presbyopia was identified in 24.7% of participants and 52.0% of those aged 35 years or older. Overall, 25.3% presented with reduced visual acuity, of whom 67.5% improved to normal range (20/30 or better) (p < 0.001).
Conclusions:
This first characterisation of the Yanomami refractive profile reveals a distinct myopia pattern shaped by high outdoor exposure and minimal near-work demands. Yet refractive correction remains effectively inaccessible, leaving preventable visual impairment unaddressed and reflecting a profound health inequity. Corrective lens provision is a high-impact, scalable intervention for this underserved community.
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