Indirect effect of 7-valent and 13-valent pneumococcal conjugated vaccines on pneumococcal pneumonia hospitalizations in elderly

• Autor(a) principal: Kislaya, Irina
• Data de Publicação: 2019
• Outros Autores: Rodrigues, Ana Paula, Sousa-Uva, Mafalda, Gómez, Verónica, Gonçalves, Paulo, Froes, Filipe, Nunes, Baltazar
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.18/5703
• topic: Pneumococcal Conjugate Vaccine; Pneumococcal Pneumonia; Hospitalization; Vacina Pneumocócica Conjugada; Pneumonia Pneumocócica; Estados de Saúde e de Doença; Determinantes da Saúde e da Doença; Saúde Pública; Portugal

Background: Pneumonia is one of the leading causes of mortality and has a high burden in morbidity. In Portugal, 7-valent pneumococcal conjugated vaccine (PCV) was used since 2001 and PCV10/13 since 2009, being the last introduced into the National Immunization Program in 2015. Methods: We conducted an ecological study to evaluate the impact of PCV7 and PCV13 on pneumococcal pneumonia (PP) hospitalizations in adults aged 65 years or more in Portugal. National hospital discharge registry data from 1998/99 to 2015/16 were used, and PP hospitalization was defined as any hospitalization coded in primary diagnosis as 481 (ICD-9-CM) or J18 (ICD-10-CM). Poisson regression models adjusted for seasonality, influenza-like illness and allowing for overdispersion was used to estimate annual average change of PP hospitalization rate. To assess PP hospitalization trends before and after PCV7 and PCV13 introduction interrupted time series analysis was performed. Results: In 1998/99 PP hospitalization rate was 7.0 per 10,000 inhabitants, varying between 3.2 (females, 65-74 years) to 20.7 (males, +85 years), and annually increasing by 16% during the pre-PCV7 period. Statistically significant reduction of 14% per year in PP hospitalization rate was observed after PCV7 introduction. Between 2004/05 and 2009/10 PP hospitalization rate decreased annually by 4% and after PCV13 introduction by 11% per year. In 2015/16 we found an overall reduction of 2.9 (CI 95%: 2.7; 3.1) PP hospitalizations per 10,000 inhabitants (598 hospitalizations) attributable to PCV13, varying from 2.2 (CI 95%: 1.3; 3.1) (female, 65-74 years) to 5.6 (CI 95%: 3.8; 7.5) (female, +85 years). Conclusions: Our results suggest that introduction of both PCV7 and PCV13 vaccines resulted in the reduction of PP hospitalizations rates among older adults.