Current epidemiological characteristics of pertussis in the Russian Federation

Abstract

Introduction. Despite the fact that since 2012 the necessary level of vaccination coverage (>95%) has been achieved and maintained in the Russian Federation, there has been a steady increase in the incidence of pertussis over the past five years. Meanwhile, one third of pediatric patients with pertussis infection had received a complete course of the pertissis vaccine. Pertussis incidence rates are high in all groups of pediatric population, which is a serious healthcare problem. Materials and methods. The factors analyzed in the study included changes in the incidence rates of pertussis over time (over years and within a year) in different age groups, history of immunization in patients with pertussis infection and laboratory test methods used to make this diagnosis. A correlation analysis of the relationship between the timeliness of vaccination coverage and the incidence of pertussis was carried out by calculating the Pearson’s correlation coefficient. The significance of differences in the incidence rates was determined by estimating the confidence intervals and calculating the t-test. Results . In the Russian Federation and the city of Moscow, the highest incidence rates are observed in infants, and are still high in children 1 to 6 years of age that are subject to vaccination. 30–40% of all reported cases of whooping cough are observed in children from 7 to 14 years of age. In this group, every second child has a history of immunization, while in adolescents 15–17 years of age the proportion of immunized patients with pertussis infection is over 60%. This suggests a reduction in the specific immune response over time and the need for introduction of booster immunization with pertussis vaccine into the National Immunization Calendar of the Russian Federation in order to improve the immunization effectiveness. Conclusions. The study allowed to make a conclusionthat high incidence rates in preschool children and increased incidence rates in school children, adolescents and adults are related to short-time duration of immune response after immunization or pertussis infection. In order to reduce the incidence of pertussis, it is necessary to keep the vaccination coverage at the level of not less than 95%, to carry out regular re-vaccinations in children aged 6–7 years, adolescents aged 14 years as well as to use decennial booster doses in adults.