In the 1980s, a subset of children were noted to have an abrupt onset of obsessive-compulsive disorder, along with neuropsychiatric symptoms triggered by an infection of some kind. This lead to the development of diagnoses of PANS (Pediatric acute-onset neuropsychiatric syndrome) and PANDAS (Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections). For decades, understanding how [...]