Reduced seroprevalence of hepatitis A virus among Japanese healthcare workers as a risk factor for occupational infection

Background: With the improvement in sanitation and hygiene, the incidence of hepatitis A virus (HAV) infection has declined, and its seroprevalence among Japanese people has been reduced. Universal HAV vaccination is yet to be implemented in Japan, and the healthcare workers (HCWs) are at higher risks of acquiring this infection. We herein report the seroepidemiology of HAV infection among HCWs at Osaka University Hospital. Methods: Between September and October 2017, we collected serum samples submitted to our laboratory for HCWs health examination and tested for the anti-HAV antibody. Results: Overall HAV seropositivity rate was 5.1% (22/436 samples). The seroprevalence was higher among those in the twenties (6.0%) and thirties (8.0%), compared to older age groups. Conclusions: In this age of internationalization, the decreasing immunity for HAV places HCWs at risk of developing the disease. As a preventive measure against occupational infection, HAV vaccination may be needed for Japanese HCWs.