RESUMO
Yersinia enterocolitica biotype 4, serotype 0:3 is by far the most common human pathogenic Yersinia enterocolitica subtype in Scandinavia. It is extraordinarily immunologically specific, and an elevated antibody titre greater than or equal 80-160 is known to indicate acute infection. This titre was measured in five population surveys conducted in 1967-78, including 3278 examined adult men and women. The prevalence of titre elevation greater than or equal to was 1.0% in 1967. In 1978 it was significantly higher, 7.7%, and also the individual course of the titre in a ten-year longitudinal survey showed a significant increase in this prevalence, indicating an increasing incidence of infection. Significant sex and age differences were seen, women and younger subjects being more frequently affected than men and older subjects. The prevalence of elevated titre showed a seasonal variation with a maximum in the spring and autumn.
