1 - Hospital Dona Estefânica, Departamento de Pediatria, Unidade de Infeciologia, ULSS José
2 - Laboratório Nacional de Referência a Infeções Respiratórias a Agentes Bacterianos, Departamento de Doenças Infeciosas, Instituto Nacional de Saúde Dr. Ricardo Jorge, Lisbon, Portugal
3 - Instituto de Microbiologia, Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
4 - Hospital Pediátrico, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
- Publication Euro Surveill. 2023;28(36):pii=2300427. https://doi.org/10.2807/1560-7917.ES.2023.28.36.2300427 (open access)
- Oral presentation, ESPID 2023;
Background: Multiple countries have recently issued alerts regarding an ongoing rise of invasive infections caused by Group A Streptococcus (iGAS). This study reports the most recent epidemiological and molecular surveillance data of pediatric iGAS in Portugal.
Materials/methods: Demographic and clinical characteristics of pediatric (<18 yrs) iGAS between Sep-2022 and May-2023 were recorded as part of an ongoing national prospective surveillance. The emm type, multilocus sequence type (ST), and number of M1UK-characteristic SNPs were obtained from whole-genome sequencing data of all available isolates (n=19).
Results: Overall, between 1 September 2022 and 31 May 2023, 89 piGAS cases were recorded (85 were confirmed and four were probable), which is 4 times higher than the average for the same period in pre-pandemic seasons (2014/15 to 2018/19, mean: 21.4 cases, range: 16–26). Between September 2022 and May 2023, the dominant diagnoses were pneumonia (25/79), mostly with empyema (20/25), and sepsis (22/79). A number of cases required admission to intensive care (27/79) and surgery (35/79) and the case fatality rate was 5.1% (4/79). Genomic sequencing (n = 55) revealed multiple genetic lineages dominated by the M1UK sublineage (26/55) and more diverse emm12 isolates (12/55).
Conclusions: Between Sep-2022 and May-2023, the paediatric iGAS cases in Portugal were significantly more numerous than in the same period of pre-pandemic years, with no increase in the CFR. This upsurge was not associated with an emerging new lineage but with multiple lineages previously circulating in Portugal, with a clear dominance of the M1UK sub-lineage and emm12.
Palavras Chave: Paediatric, Portugal, Streptococcus pyogenes