Abstract

In the 90-ies there has been observed an increased pertussis incidence rate, despite the high percentage of vaccination among the children’s population, between 86% and 99%, depending on the region. Up till now pertussis had been diagnosed mainly in infants and children aged between 2 and 5 but during the last decade the disease was diagnosed mainly in children above 5 years of age who underwent a full cycle of pertussis vaccination. In searching for the reasons of that epidemiologic situation there have been suggested changes in bacteria antigenicity, the phenomenon of the postvaccine immunity decrease, unjustified vaccination exemptions and a possibility of immunological system disorders. The study assesses selected parameters of cellular and humoral response together with the levels of postvaccine antibodies resulting after immunization with specific vaccines in children with past pertussis.