[The effect of vaccination status on the clinical form and outcome of the disease in smallpox patients (author's transl)].

During the smallpox epidemic in Yugoslavia in 1972, which involved 175 persons altogether, with 35 (=20 per cent) fatal cases, a number of very important aspects emerged, especially at Kosowo (124 cases0: smallpox vaccination gives almost complete protection for 5 years and a relative immunity for about 10 years. Vaccinations carried out on the first 2 days after contact with smallpox patients provide a convincing protection, reduce mortality and result in the appearance of a particular form of smallpox. The highest mortality (52.1 per cent) was seen in persons who had never been vaccinated, with the appearance of the "flat type" (47.8 per cent). Hemorrhagic smallpox was seen in 8 out of 9 persons who were vaccinated too late after contact and had an immunological deficiency.