The Relation Between Toxoplasmosis and Focal Exudative Retinochoroiditis* *From the Division of Allergy and Infectious Disease, Department of Medicine, and the Department of Ophthalmology, The Johns Hopkins Hospital and Medical School. This study was supported in part by the National Institute of Allergy and Infectious Diseases, U. S. Public Health Service (training grant 2-E-9), the Upjohn Company, and the Merck, Sharp, and Dohme fellowship grants in allergy, the Consolidated Gift Fund for Pediatric Allergy Research of The John Hopkins Hospital, and U. S. Public Health Service (grant NB-00043, etiology and treatment of uveitis).