Retrospective Study of the Clinical Epidemiological Characteristics of Pertussis in Infants Prior to Their First Vaccination in the Russian Federation

INTRODUCTION The coverage of pediatric pertussis vaccination in the Russian Federation is high, generally using a diphtheria, tetanus, and whole-cell pertussis vaccine in a 3-, 4.5-, and 6-month primary series and with a booster at 18 months of age. However, with no registered pertussis vaccines for adults, unvaccinated adolescents and adults can be a major source of infection of infants under 3 months of age. METHODS A multicenter, retrospective, clinical epidemiological analysis to characterize pertussis in infants aged up to 3 months who contracted pertussis and were hospitalized in four different cities in the Russian Federation was performed. Archived medical records and a questionnaire were used to collect the relevant epidemiological and clinical aspects for each case of pertussis over a 2-year period. RESULTS Infants in four different regions of the Russian Federation in the first 3 months of life, prior to their first pertussis vaccination, are at risk of pertussis infection. The severity is generally worse in neonates, and can lead to complications that can require intensive care. CONCLUSION Prior to vaccination, young infants in the Russian Federation remain vulnerable to severe pertussis, which may be worsened by their proximity to unvaccinated adults.