Seroprevalence survey on measles, mumps, rubella and varicella antibodies in healthcare workers in Japan: sex, age, occupational-related differences and vaccine efficacy

Abstract

SUMMARYA seroprevalence survey on measles, mumps, rubella and varicella was conducted on healthcare workers (HCWs) at Shimane University Hospital, Japan utilizing an enzyme immunoassay. Of 1811 HCWs tested, 91·8% were seropositive to measles, 92·1% to mumps, 89·5% to rubella and 96·3% to varicella. Sex-related differences in seroprevalence were found in rubella (males vs. females: 84·7 vs. 92·2%, P < 0·001). Moreover, males aged 30–39 years were most susceptible to rubella (22·4%), which may be attributed to the design of childhood immunization programmes in Japan. Individuals aged ⩽29 years were more susceptible to measles (14·3%) and mumps (10·9%), compared to other age groups. There were no significant sex- and age-related differences in varicella seroprevalence. The physician occupational group was more susceptible to rubella, but no significant occupational-related difference was observed in the other diseases. Susceptible subjects, with negative or equivocal serological results were given a vaccine which induced seroconversion in most vaccinees. Seroconversion occurred more frequently in the equivocal group than in the negative group. These findings provide a new insight for the seroprevalence survey of vaccine-preventable diseases in Japanese HCWs with special reference to vaccine efficacy.