Risk factors for hepatitis B carrier status among blood donors of the National Blood Center, Thai Red Cross Society.

A study of risk factors for hepatitis B carriers among voluntary blood donors of the National Blood Center, Thai Red Cross Society was carried out in a case-control study design during January 1989 to June 1990. Cases were 876 blood donors whose blood identified HBsAg at time of recruitment and continued positive for more than 6 months. Controls were 1,750 blood donors whose blood was free from HBsAg who came for blood donation at the same period as the cases. The ratio of cases:controls = 1:2. Self-administered questionnaires were constructed and pretested before using both cases and controls. The study revealed that the risk factors for hepatitis B among voluntary blood donors were age of less than 30 years old; low socioeconomic status (family income of less than 8,000 Baht/month); single status, especially males; male occupations of students, monks, nongovernment workers compared with government officials; female occupations of laborers, students, nongovernment workers and government officials compared with housewives. Sharing of nail clippers, used blades and tooth brushes among family members are proved to be risk factors, especially among males. In addition, sharing of used blades in barber shops proved to be a risk among males while sharing of nail clippers in beauty salons, history of ear-piercing at department stores or history of caesarean section among females could not be shown to be risk factors.(ABSTRACT TRUNCATED AT 250 WORDS)