We studied retrospectively the medical records of all patients (n = 150) diagnosed, by cerebrospinal fluid (CSF) analysis, with neuroborreliosis (NB) in Jönköping County, Sweden during 2000-2005. The number of NB cases increased from 5/100,000 to 10/100,000 inhabitants/year. In 17% of the patients, anti-Borrelia antibodies were found in CSF but not in serum at the time of diagnosis. Facial palsy, headache and fever were frequent manifestations in children, whereas unspecific muscle and joint pain were the most commonly reported symptoms in older patients. Post-treatment symptoms persisting for more than 6 months occurred in 13%, and the patients concerned were significantly older, had longer-lasting symptoms prior to treatment, had higher levels of Borrelia-specific IgG in CSF, and more often had radiculitis. The total cost of NB-related healthcare was estimated to be euro500,000 for the entire study group (euro3300 per patient), and the cost of social benefits was estimated to be euro134,000 (euro2000 per patient). CSF analysis is necessary for the diagnosis of NB, because some patients develop antibodies in serum later than in CSF. Early diagnosis of borreliosis would result in reduced human suffering and in economic gain.