[Seroprevalence of viral markers of hepatitis B among health professionals. Multicenter study in Mexico].

To determine the prevalence of serological markers for hepatitis B infection among health care workers (HCW) in Mexico we surveyed 1072 volunteers from 26 hospitals in 12 states, from which only 1017 fulfilled the inclusion criteria: 82 patients (8.1%) were excluded because of lipemic and/or hemolyzed serum, leaving 935 persons in the study. The study population consisted of physicians, nurses, laboratory chemists, health laboratory technicians and odontologists. All of them had been working in their respective fields and in contact with biological materials for at least 12 months. None of them had been vaccinated for hepatitis B. We determined the presence of HBsAg and anti-HBs by the ELISA method. The participants' mean age was 31.4 years (range: 18-72) and their mean working time was 7.8 years. 615 were female and 320 male. The HBsAg was positive in 11 (1.2%) and the anti-HBs in 91 cases (9.7%). These results suggest that HCW in Mexico have a greater relative risk of becoming infected with the HB virus than the general population. Relative risks were particularly higher for the health laboratory technicians and the physicians. These results confirm that biohazard measures must be reinforced and that the application of HB virus vaccine could be recommended for health care workers.