This study presents the results of a hospital survey on Lyme disease in children living in upper Normandy, a region that is quite densely wooded (with 18% forest areas and woods). The aim of this survey was to assess the prevalence of this disease in children from the Seine-Maritime and L'Eure, hospitalized in pediatric wards in the Seine-Maritime department, which includes Rouen, Dieppe, Fécamp, Elbeuf, and Le Havre. Fifteen cases of Lyme disease were diagnosed between September 1988 and June 1997. The children (6 girls and 9 boys) were aged between 5 and 14 years old. Only 7 subjects showed primary symptoms, while secondary symptoms were observed in 12 children. In the study population, a high prevalence (11 out of the 15 children) of neurological disorders was found. The following secondary symptoms were noted: 5 cases of erythema migrans, 2 cases of non-malignant cutaneous lymphocytoma, and 4 cases which in fact had previously displayed primary clinical signs (3 subjects with erythema migrans and 1 subject with non-malignant cutaneous lymphocytoma); 7 cases of uni- or bilateral facial paralysis, the most frequent neurological manifestation with or without lymphocytic meningitis; 1 case of central vestibular syndrome with a hyperalgesic meningoradicular reaction in the vicinity of the tick bite; 1 case of peripheral radicular involvement and intense pain in the left lower limb; 4 cases of ocular disorders (3 diplopias, 1 bilateral conjunctivitis complicated by kerato-uveitis, 1 bilateral complete cecitis). Only 10 child had rheumatological symptoms, i.e., Lyme arthritis of the right knee. Treatment consisted of amoxicillin (10 children) administered at a dosage of 50 to 100 mg/kg/d over a period ranging from 10 days to 1 month, or ceftriaxone (7 children) at a dosage of 50 to 100 mg/kg/d administered intravenously over a period ranging from 8 days to 3 weeks. Two of the children received combined antibiotic therapy, and 5 subjects had adjunct corticotherapy.