Pneumococci remain the main cause of complicated pediatric pneumonia in the post-pandemic era despite extensive pneumococcal vaccine use
Authors: Gomes-Silva Joana , Pinho Marcos D. , Friães Ana , Ramirez Mário , Melo-Cristino José , Silva-Costa Catarina ,   the Portuguese Group for the Study of Streptococcal Infections, Pinto Margarida , Seruca Miguel , Marques João , Peres Isabel , Pina Teresa , Lourenço Isabel , Marcelo Cristina , Daniel Isabel , Chantre Odete , Mendes Vasco , Gião Marília , Ferreira Rui , Ribeiro Rui Tomé , Pontes Celeste , Boaventura Luísa , Reis Teresa , Oliveira Henrique , Chaves Catarina , Silva Mariana , Aguiar Ana , Loureiro Hugo , Pedrosa Adriana , Costa Hermínia , Silva Maria Fátima , Afonso Maria Amélia , Fardilha Mariana , Novais Natália , Brito Isabel , Lito Luís Marques , Fonseca Ana Bruschy , Pessanha Maria Ana , Gonçalves Elsa , Morais Teresa , Toscano Cristina , Cristovam Elisabete , Lopes Paulo , Lameirão Angelina , Abreu Gabriela , Selaru Aurélia , Mota Vieira Ana Paula , Tomaz Margarida , Ferreira Cláudia , Nicolau Marta , Castro Ana Paula , Lopes Virgínia , Cruz Hugo , Fonseca Fernando , Martins Nádia , Leite Carla , Castro Ana Paula , Vicente Filipa , Pereira Margarida , Fontes Ilse , Falcão Maria Paula , Semedo Rui , Marrão Gina , Silva Filipa , Ribeiro Manuela , Gonçalves Helena , Faustino Alberta , Iglesias Maria Cármen , Coutinho Adriana , Correia Ana Bela , Gonçalves Luísa , Aliyeva Elzara , Schäfer Sandra , Portugal Clara , Monge Isabel , Diogo José , Fortunato Filipa , Carneiro Leonardo , Marta José , Kruptsala Nadiya , Fidalgo Cláudia , Diaz Raquel , Ferreira Sónia , Cravo Roxo Inês , Vale Isabel , Tomás Maria João , Read Maria Antónia , Alves Valquíria , Monteiro Margarida , Faria João , Mota Freitas José , Vieira Sandra , Calado Elsa , Miguel Bruno , Nogueira Martins L , Menezes Maria Favila , Rego de Sousa Maria José , Calle Maria , Bettencourt Viana Mariana , Oliveira Marvin , Macedo Hugo , Rodrigues Vitória , Marques Sofia , Selada Joana , Pereira Patrícia , Azevedo Manuela , Duarte Jesuína , Bernardo Joana , Tapadinhas Inês , Resende Ana Filipa , Bernardo Andreia , Oliveira Luísa , Banza Susana , Moreira Ezequiel , Ferreira Carla , Vicente Adília , Bragança Cristina , Lucas Maria , Gouveia Pestana Paula , Amantegui Patrícia , Mota Preto Cristina , Sampaio Sara F. , Jesus Ana , Lourinha Marisol ,   the Portuguese Study Group of Invasive Pneumococcal Disease of the Pediatric Infectious Disease Society, Gouveia Catarina , Tomé Teresa , Rebelo Mónica , Teixeira Ana , Virtuoso Maria João , Guerreiro Nancy , Rodrigues Fernanda , Resende Cristina , Aires Sónia , Fenandes Agostinho , Prata Filipa , Vieira Marisa , Morais Rita , Moreira Diana , Carvalho Isabel , Costa Alexandra , Teixeira Ana , Ferreira Cristina , Seves Graça , Marques Laura , Braga Ana , Guedes Margarida , Dinis Maria José , Gaspar Eurico , Camacho Bernardo , Novais Céu , Zarcos Maria Manuel , Tavares Margarida , Costa Alves Manuela , Lima Sofia , Cruz Carla , Brandão Manuela , Correia Paula , Fraga Sofia , Franco João , Almeida Sílvia , Faria Cristina , Arosa Sofia , Cunha Florbela , Rodrigues Hugo , Cunha Joaquim , Monteiro Cláudia , Veiga Estela , Pereira Fernanda , Ferreira Manuela , Sousa Álvaro , Lopes Francisca , Santos Sara , Teixeira Ana Luísa , Marcelo Fernanda , Carvalho Pedro , Pereira Filomena , Rodrigues Gustavo , Cabral Marta , Nunes Maria Ana S. , Flores Pedro , Cunha Manuel , Gomes Dora , Calado Nunes João , Massa Rosário , Nunes Fátima , Monteiro Isabel , Didelet Cristina , Salgado António , Gonçalves Luís 
Published: November 2024

Nucleic acid amplification tests (NAATs) greatly enhance the capacity to identify the etiology of pediatric complicated pneumonia. However, the use of pneumococcal conjugate vaccines could reduce the importance of Streptococcus pneumoniae in pediatric complicated pneumonia with the potential emergence of other bacterial agents. Using an expanded NAAT in culture negative pleural fluid or empyema samples collected in 2010–2024 (n = 554) in Portugal, we show that S. pneumoniae remains the most frequent agent despite decades of pneumococcal conjugate vaccine use and the COVID-19 pandemic. A rebound in pediatric complicated pneumonia occurred post-pandemic, including a rise in cases by Streptococcus pyogenes and Haemophilus influenzae. Empiric therapy of pediatric complicated pneumonia should still consider S. pneumoniae as the most likely cause, even in countries where the pneumococcal conjugate vaccine is in the national immunization program with a high uptake.