Cunha, IAntunes, H2013-09-132013-09-132001Acta Med Port. 2001;14(5-6):479-82.http://hdl.handle.net/10400.23/498AIM: To find the prevalence of antibody to hepatitis A virus in the population of the North of Portugal. MATERIAL AND METHODS: Ten General Practitioners were asked to provide blood samples from patients who would need blood tests for any reason other than acute hepatitis, during January and February 1996. In this way, 381 samples were obtained for assessment of anti hepatitis A virus antibodies using a commercial radioimmunassay ELISA. All subjects gave their informed consent and answered to a protocol regarding age, sex, geographic area, number of people per household and sewage systems. The statistics were performed using SPSS. RESULTS: The 381 subjects were distributed into eight age groups: I (1-4 years)--57; II (5-9 years)--57; III (10-14 years)--26; IV (15-19 years)--41; V (20-29 years)--55; VI (30-39 years)--51; VII (40-49 years)--41; VIII--(equal or more than 50 years)--53. The prevalence of anti HAV antibodies per group-percentage (number), (confidence intervals), were: I--7.0% (4) (3-17%); II--15.8% (9), (9-27%); III--26.9% (7) (14-46%); IV--51.2% (21) (37-66%); V--85.5% (47) (74-92%); VI--72.5% (37) (59-83%); VII--87.8% (36) (75-95%); VIII--88.7% (47) (80-93%). CONCLUSION: The comparison with previous data (Lecour et al.) shows improvement in sanitary conditions of population, with associated lower prevalence of anti hepatitis A virus antibody.porHepatite APrevalênciaPortugalAnticorpo da Hepatite Ajournal article