Journal Article SURVEY FOR SERO-IMMUNITY TO POLIOMYELITIS IN PERU AND COLOMBIA: WITH COMMENTS ON THE CHANGING PATTERN OF OCCURRENCE OF POLIOMYELITIS IN TROPICAL AREAS Get access HENRY M. GELFAND, M.D., M.P.H., HENRY M. GELFAND, M.D., M.P.H. Division of Epidemiology, Department of Tropical Medicine and Public Health, Medical School, Tulane University of LouisianaNew Orleans, La., U.S.A. Search for other works by this author on: Oxford Academic PubMed Google Scholar JOHN P. FOX, M.D., Ph.D., M.P.H., JOHN P. FOX, M.D., Ph.D., M.P.H. Division of Epidemiology, Department of Tropical Medicine and Public Health, Medical School, Tulane University of LouisianaNew Orleans, La., U.S.A. Search for other works by this author on: Oxford Academic PubMed Google Scholar JUAN ANTONIO MONTOYA, O., M.D. JUAN ANTONIO MONTOYA, O., M.D. Departamento de Medkina Preventiva y Salud Publica, Facultad de Medicina, Universidad del ValleCali, Colombia Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Tropical Pediatrics, Volume 3, Issue 2, September 1957, Pages 51–61, https://doi.org/10.1093/oxfordjournals.tropej.a057457 Published: 01 September 1957