Pertussis Outbreak During 2023 in Gipuzkoa, North Spain
José María Marimón,
Milagrosa Montes,
Nahikari Vizuete,
Lorea Alvarez Guerrico,
Adrian Hugo Aginagalde,
Alba Mir-Cros,
Juan José González-López,
Diego Vicente
Affiliations
José María Marimón
Biogipuzkoa Health Research Institute, Infectious Diseases Area, Microbiology Department, Osakidetza Basque Health Service, Donostialdea Integrated Health Organization, Donostia University Hospital, 20014 Donostia-San Sebastian, Spain
Milagrosa Montes
Biogipuzkoa Health Research Institute, Infectious Diseases Area, Microbiology Department, Osakidetza Basque Health Service, Donostialdea Integrated Health Organization, Donostia University Hospital, 20014 Donostia-San Sebastian, Spain
Nahikari Vizuete
Sub-Directorate for Public Health and Addictions of Gipuzkoa, Ministry of Health of the Basque Government, 20013 Donostia-San Sebastian, Spain
Lorea Alvarez Guerrico
Sub-Directorate for Public Health and Addictions of Gipuzkoa, Ministry of Health of the Basque Government, 20013 Donostia-San Sebastian, Spain
Adrian Hugo Aginagalde
Sub-Directorate for Public Health and Addictions of Gipuzkoa, Ministry of Health of the Basque Government, 20013 Donostia-San Sebastian, Spain
Alba Mir-Cros
Department of Clinical Microbiology, Vall d’Hebron Hospital Universitari, Passeig Vall d’Hebron 119-129, 08035 Barcelona, Spain
Juan José González-López
Department of Clinical Microbiology, Vall d’Hebron Hospital Universitari, Passeig Vall d’Hebron 119-129, 08035 Barcelona, Spain
Diego Vicente
Biogipuzkoa Health Research Institute, Infectious Diseases Area, Microbiology Department, Osakidetza Basque Health Service, Donostialdea Integrated Health Organization, Donostia University Hospital, 20014 Donostia-San Sebastian, Spain
Background: Pertussis has re-emerged in many countries despite the wide use of vaccines for over 60 years. During 2023, we observed an increase in the incidence of pertussis in Gipuzkoa, north of Spain (with a population of 657,140 inhabitants), mainly affecting children between 11 and 15 years of age. Methods: This study included all confirmed cases diagnosed by PCR in nasopharyngeal swab samples. The genome of seven isolates collected in 2023 was sequenced. Results: Between 2018 and 2023, 884 cases of whooping cough were diagnosed. Pertussis incidence (in cases per 100,000 inhabitants) decreased from 36.7 in 2018 to no cases in 2021, increasing again to 56.8 in 2023. In 2023, the age group of 11–15 years old had the highest incidence rate of 409.3. Only 2 of the 56 children ptxA1/ptxP3/prn2/fim2-1/fim3-1 allelic combination), with all of them expressing the pertactin antigen. Conclusions: Immunity waning after the last dose of vaccination at 6 years old, together with the lack of circulation of Bordetella pertussis during the COVID-19 pandemic, were probably the main reasons for the high increase in the incidence of pertussis in Gipuzkoa in 2023.
