Transmission of hepatitis C virus by health care workers in a rural area of Japan.

OBJECTIVE

The prevailing route of hepatitis C virus (HCV) transmission in Japan is unclear, so we expected that a survey of routes of HCV infection in an endemic area might clarify the mode of transmission.

METHODS

We screened 2049 inhabitants in an isolated rural village of Fukuoka, Japan using HCV markers. All serum samples were assayed for antibody to HCV (anti-HCV) (ELISA), and anti-HCV-positive samples were assayed for HCV RNA and genotype (polymerase chain reaction).

RESULTS

The prevalence of anti-HCV was 19.7% and increased with advancing age, from zero in the under 19 yr of age group to 30.7% in the 60-69 yr of age group. HCV RNA was detected in 82.9% of the anti-HCV-positive inhabitants, and 88.3% of them had genotype II. Anti-HCV was detected in 17.8% of the children of HCV-carrier mothers, similar to the rate (15.4%) for all inhabitants in the 40-49 yr of age group, the same age group for the mean age of the anti-HCV-positive children. Anti-HCV was detected in 34.8% of husbands of female HCV carriers and in 22.2% of wives of male HCV carriers, similar to the rates (36.2% in males and 26.6% in females) for all inhabitants in 60-69 yr of age group, the same age group for the mean ages of carriers' spouses. The prevalence of anti-HCV was the highest in inhabitants of one of three distinct areas of this village where patients had often been injected with insufficiently sterilized syringes and needles for treatment in the same clinic.

CONCLUSION

These observations suggest that medical intervention probably played a more important role in the spread of the HCV infection in the village studied than did familial transmission.