BACKGROUND: Ocular inflammation causes significant visual morbidity in the United States, yet little is known about the epidemiology of infectious uveitis and scleritis. This study aims to evaluate the epidemiology of infectious uveitis/scleritis employing a large national medical claims database. METHODS: This was a retrospective, case-control study, employing Optum's de-identified Clinformatics® Data Mart Database, containing data from 21.5 million privately insured individuals with enrollment for at least 15 months within 2007-2015. Inclusion in the uveitis/scleritis sample required an index uveitis/scleritis diagnosis based on International Classification of Diseases, Ninth Revision (ICD-9) codes. Exclusion criteria included index date within 3 months after intraocular surgery. Rates for uveitis/scleritis were determined by anatomic site. Multivariable logistic regression analyses were performed to determine odds ratios for the incidence and prevalence of uveitis/scleritis by anatomic category. FINDINGS: Infectious etiologies accounted for less than 20% of uveitis/scleritis, with mean rates of 18.9 (incidence) and 60.6 (prevalence) per 100,000 persons. The mean prevalences of infectious anterior, intermediate, posterior, panuveitis, and scleritis were 27.7, 0.17, 23.4, 4.4, and 4.6, per 100,000, respectively. Overall risk of prevalent infectious uveitis/scleritis increased with age (OR>3.3 for each decade over age 18, p<0.01), female sex (OR = 1.2, p<0.01), non-Hispanic white race (OR<1 for all other races, p<0.01), as well as the East South Central census division (OR = 1.2, p<0.01), comprising Alabama, Kentucky, Missouri, and Tennessee. Medical comorbidities, including HIV infection (OR = 6.4, p<0.01) and rheumatologic disease (OR = 1.9, p<0.01), were common in the infectious uveitis/scleritis cohort. CONCLUSIONS: The incidence and prevalence of infectious uveitis/scleritis in the United States were higher than previously reported estimates but remained lower than in developing countries. Rates varied by age, sex, race, and medical comorbidities, and may reflect differential susceptibility to various infectious agents with disparate geographic distributions within the United States.