SEROPREVALENCE OF RUBELLA AMONG WOMEN OF CHILDBEARING AGE IN SWITZERLAND

A seroepidemiological study was carried out in Switzerland to define t he population susceptible to rubella among women of childbearing age. IgG antibodies to rubella virus were determined in 9,046 women giving birth between 1 August 1990 and 30 September 1991 in 23 of 26 Swiss ca ntons. These sera represented 10-20 % of the yearly total number of bi rths in each Swiss canton. Anti-rubella IgG was measured by an automat ed enzyme-linked fluorescent assay for use with a commercial system (V idas Rub IgG, bio-Merieux, France). Before the study population was sc reened, the commercial system was compared to the traditional hemagglu tination-inhibition (HAI) test using 500 consecutive samples from part urient women. The sensitivity was 97.7 %, the specificity was 100 %, a nd agreement between the two tests was 97.8 %. The discrepancies corre sponded to very low titres of antibodies as measured by HAI. The serop revalence of rubella nationwide in women of childbearing age in Switze rland was 94.3 %. The sere prevalence was higher (96.5 %) in the 5,677 women of Swiss nationality than in the 3,090 women of a different nat ionality (90.4 %) (p < 0.001). In Swiss women the seroprevalence of ru bella did not increase significantly with age and was identical in pri miparous and in multiparous women, thus indicating that women of child bearing age are probably not sufficiently immunised.