Epidemiology of rubella infections in Austria: important lessons to be learned.

In order to ascertain the epidemiology of rubella infections in Austria, a seroepidemiological study was performed. Data collected from 115 cases diagnosed at the Institute of Hygiene and Social Medicine of the University of Innsbruck during 2001 were evaluated. The results indicate this infection can no longer be categorised as a paediatric disease (mean age, 18.5 years), and several other findings were particularly striking: (i) 47% of the patients had elevated C-reactive protein levels and 50% had increased anti-streptolysin O titres; (ii) only a few patients complained of fever, while symptoms such as rash and lymphadenopathy, which are also associated with several other viral infections, including HIV, were found frequently; and (iii) the 115 rubella cases detected in the 1-year study period represented an incidence of >13 per 100,000 population. This high incidence of infection underlines the need for further improvement of diagnostic tests and more successful vaccine strategies.