Mumps in Poland since 1990 to 2003; epidemiology and antibody prevalence.

The annual incidence of mumps in Poland over the period 1990-2003 was 45-570 per 100,000 population with the epidemic peak every 4-5 years. Till 2003, mumps vaccination has not been included in the part of National Immunisation Program in Poland that comprises the obligatory vaccinations. However, mumps vaccination was recommended by National Health Authority for children at the second year of life and it could be obtained privately. The proportion of vaccinated children has increased by 50% in last years. It has influenced on decreasing of number of notified mumps cases in Poland, on lengthening of inter-epidemic period as well as on drift of infections towards older groups of children. The results of serological survey carried out on 1390 serum samples have indicated, that the proportion of positive serum samples (>11 VE/ml) was only 24.1% for children aged 1-4 years, 45.4% for children aged 5-9 years, 72.5% for age group 10-14 years, and over 85% for persons aged 15-30 years. Epidemiological data and the high proportion of individuals with negative titres of specific mumps IgG antibodies justify the need of introduction of obligatory mass immunisation against mumps in Poland.