Yersinia enterocolitica infections with a wide spectrum of clinical presentations have been reported in South Africa. An additional 18 cases were encountered in the eastern Cape region during the period May 1982 - December 1984. Y. enterocolitica isolates comprised 1% of 1,634 faecal examinations performed by the Microbiology Department of the South African Institute for Medical Research in Port Elizabeth during this period, compared with isolation rates of 5.1% for shigellae, 3.7% for salmonellae and 1.3% for Campylobacter jejuni. The majority of Y. enterocolitica infections were in children who presented with diarrhoea and only 2 systemic cases were documented. Although more cases were seen in summer there was no distinct seasonal incidence and this may be attributed to the even climatic conditions prevailing in the region.