Pertussis in Poland in 2022

IntroductionThe epidemiological situation of pertussis in Poland in 2022 was influenced by the cancellation of the COVID-19 epidemic and the introduction of an epidemic threat. Decisions related to the gradual easing of restrictions on social contacts and the abolition of the obligation to wear masks caused the number of pertussis cases to slowly start to increase. The most effective strategy for preventing pertussis remains the immunization of children in accordance with the National Immunization Program, and in the case of adults, vaccination repeated systematically every 10 years and immunization of pregnant women in the second/third trimester of each pregnancy. Pertussis remains a public health problem because the immunity obtained through vaccination does not last a lifetime.ObjectivesThe aim of the study was to assess the epidemiological situation of pertussis in Poland in 2022 compared to the situation in previous years, with particular emphasis on assessing the impact of the COVID-19 pandemic and assessing the vaccination status of children against pertussis.Material and MethodsThe assessment of the epidemiological situation of pertussis in Poland was made based on the results of the analysis of individual reports on pertussis cases registered at the NIPH NIH – NRI in the Epibaza system and data from the annual bulletins "Infectious diseases and poisonings in Poland" and the bulletin "Vaccinations in Poland in 2022".ResultsIn 2022, 371 cases of pertussis were recorded. The incidence was 0.98/100 000 and was 104% higher than in 2021. The highest incidence of pertussis occurred in children aged 0-4 years (6.7/100 000), and high in children aged 5-9 years (2.0/100 000). Over 51% of cases concerned people over 15 years of age. A higher incidence was observed in women in general compared to men, and a higher incidence in cities than in rural areas. In 2022, among people with pertussis, 151 (41%) required hospitalization. In 2022, the vaccination rate of children aged 2 years with 4 doses of the pertussis vaccine was 94.3% in total. In 2022, one case of disease resulting in death due to pertussis was reported to the epidemiological surveillance system.ConclusionsIn Poland, in 2022, there was an increase in the number of pertussis cases compared to the previous year, which was undoubtedly influenced by the gradual lifting of restrictions on social contacts and the obligation to wear masks. The increase in the number of people susceptible to pertussis may lead to the occurrence of compensatory epidemics in the future, therefore a high level of vaccination of the population (above 95%) should be maintained to prevent new cases.