Jerusalem syndrome

Jerusalem syndrome is a group of mental phenomena in which a visit to the city of Jerusalem triggers religiously themed ideas, delusions, or psychotic episodes in travelers of various faiths, including Jews, Christians, and Muslims. It is not listed as a distinct diagnosis in the Diagnostic and Statistical Manual of Mental Disorders or the International Classification of Diseases, but clinicians in Jerusalem have documented it since it was first clinically described in the 1930s by psychiatrist Heinz Hermann, with earlier, similar cases recorded informally since the Middle Ages under names such as the Jerusalemian fever. Researchers group cases into three types: psychosis that overlays a pre-existing mental illness, an intense but not necessarily pathological religious obsession, and acute psychosis appearing suddenly in a person with no previous psychiatric history, the last of which resolves within days or weeks of leaving the city. Hospital data from 1980 to 1993 recorded roughly 100 tourists a year experiencing severe Jerusalem-themed mental disturbance, about 40 of whom needed hospitalization, though some researchers argue this rate is not unusual compared with other major tourist cities.