Background: Streptococcal infection has been linked with the development of obsessive-compulsive disorder (OCD) and other mental disorders, a concept termed pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS). Most studies of this association have been small with conflicting results. The aim of this study was to investigate this association, at an ecological level, in Colombia. Methods & Materials: A population-based ecological study was conducted using data from the nationwide Colombian health information system RIPS (Health Services Provision Individual Record), from 1-January-2009 to 31-December-2016, assessing incidence rates of upper respiratory tract infections (URTI)(B95.0-J01.9-J02.0-J02.9-J03.0) and OCD (F42.9) and bipolar affective disorder (BAD)(F31.9). We used reference populations to calculate incidence rates(cases/100,000pop.). Nonlinear regression models were run between URTIs (independent variables) and OCD/BAD (dependent variables)(p < 0.05), using licensed StataIC14®. Results: A total of 74,019 BAD and 7,093 OCD cases were considered. We analyzed data of 69,090 URTI cases. BAD rates varied from 0.0-480.2 cases/100,000pop, OCD 0.0-33.46, URTI: 0.0-3679 acute sinusitis, 7.15-8438.77 acute pharyngitis and 0.0-5436.06 streptococcal amygdalitis. Variation in OCD and BAD incidence showed a significant association in all models (r2 > 0.32;p < 0.001), higher between acute pharyngitis(J02.9) and OCD (r2 = 0.7920), followed by acute pharyngitis(J02.9) and BAD (r2 = 0.7352), acute sinusitis(J01.9) and OCD (r2 = 0.7082), acute sinusitis(J01.9) and BAD (r2 = 0.6771), streptococcal pharyngitis(J02.0) and OCD (r2 = 0.4258), streptococcal amygdalitis(J03.0) and OCD (r2 = 0.4051), streptococcal pharyngitis(J02.0) and BAD (r2 = 0.3800), streptococcal amygdalitis(J03.0) and BAD (r2 = 0.3624), Streptococcus group A infection(B95.0) and BAD (r2 = 0.3469) and Streptococcus group A infection(B95.0) and OCD (r2 = 0.3261), among others. Conclusion: This large-data study investigating key aspects of the PANDAS hypothesis found, as has been also recently raised from a large Danish study (JAMA 2017), that individuals with a streptococcal throat, but also other URT infections are associated with different mental disorders. They find it with OCD, which we also did, and we also added BAD. As suggested, this support important elements of the diagnostic concept of pediatric acute-onset neuropsychiatric syndrome.