RISK-FACTORS FOR ACUTE HEPATITIS-B - A CASE-CONTROL STUDY

Over the period 1989-1991 a case-control study was carried out in the area of Naples comparing 162 subjects with acute hepatitis B and 788 h ospitalized control subjects, The results of multivariate analysis sho wed that surgical intervention (odds ratio 3.8; 95% CI 1.2-11.7), hous ehold contact with an hepatitis B surface antigen (HBsAg) positive car rier (odds ratio 2.7; 95% CI 1.1-6.7) and intravenous drug use (odds r atio 13.0; 35% CI 3.2-52.7) were risk factors independently associated with hepatitis B, No association was found with the other risk. facto rs considered, such as blood transfusion, hospitalization, other percu taneous exposures, dental therapy, contact with an icteric case, barbe r shop shaving and two or more sexual partners. As a significant propo rtion of the general population undergoes surgical intervention, effic ient procedures for sterilization of instruments should be implemented , together with the use of disposable materials, to control the spread of HBV infection in surgical settings.