Journal Article Correspondence Get access I. A. Llovera, I. A. Llovera Division of Epidemiology, School of Public Health, and Department of Pediatrics, College of Physicians and Surgeons, Columbia University, Columbia UniversityNew York Search for other works by this author on: Oxford Academic PubMed Google Scholar S. H. Vermund, S. H. Vermund Division of Epidemiology, School of Public Health, and Department of Pediatrics, College of Physicians and Surgeons, Columbia University, Columbia UniversityNew York Search for other works by this author on: Oxford Academic PubMed Google Scholar A. U. Pelaez, A. U. Pelaez Department of Clinical Laboratories, San Vicente de Paul University HospitalMedellin, Colombia Search for other works by this author on: Oxford Academic PubMed Google Scholar R. Manotas, R. Manotas Department of Pediatrics, Archbishop Caycedo Children's HospitalMedellin, Colombia Search for other works by this author on: Oxford Academic PubMed Google Scholar G. Gonzalez G. Gonzalez Department of Epidemiology, National School of Public Health, University of AntioquiaMedellin, Colombia Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Tropical Pediatrics, Volume 33, Issue 3, June 1987, Pages 158–159, https://doi.org/10.1093/tropej/33.3.158 Published: 01 June 1987