1. Pan American Health Organization, Washington, DC 20037, USA
2. Division of Ophthalmology, Ribeirão Preto Medical School, University of São Paulo, Ribeirao Preto 14015-010, Brazil
3. Department of Ophthalmology and Visual Sciences, Federal University of São Paulo, Sao Paulo 04023-062, Brazil
4. Department of Anthropology and Archaeology, University of Calgary, Calgary, AB T2N 4N1, Canada
5. Independent Researcher, Bogota 110111, Colombia