Rapid communication Open Access
Like 0


Since autumn 2022, observed numbers of paediatric invasive group A infections in Portugal (n = 89) were higher than in pre-COVID-19 seasons. 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 M1 sublineage (26/55) and more diverse 12 isolates (12/55).


Article metrics loading...

Loading full text...

Full text loading...



  1. European Centre for Disease Prevention and Control (ECDC). Increase in invasive group A streptococcal infections among children in Europe, including fatalities. Stockholm: ECDC; 2022. Available from: https://www.ecdc.europa.eu/en/news-events/increase-invasive-group-streptococcal-infections-among-children-europe-including
  2. Miller KM, Lamagni T, Cherian T, Cannon JW, Parks T, Adegbola RA, et al. Standardization of epidemiological surveillance of invasive group A streptococcal infections. Open Forum Infect Dis. 2022;9(Suppl 1):S31-40.  https://doi.org/10.1093/ofid/ofac281  PMID: 36128405 
  3. Friães A, Mamede R, Ferreira M, Melo-Cristino J, Ramirez M. Annotated whole-genome multilocus sequence typing schema for scalable high-resolution typing of Streptococcus pyogenes. J Clin Microbiol. 2022;60(6):e0031522.  https://doi.org/10.1128/jcm.00315-22  PMID: 35531659 
  4. Lynskey NN, Jauneikaite E, Li HK, Zhi X, Turner CE, Mosavie M, et al. Emergence of dominant toxigenic M1T1 Streptococcus pyogenes clone during increased scarlet fever activity in England: a population-based molecular epidemiological study. Lancet Infect Dis. 2019;19(11):1209-18.  https://doi.org/10.1016/S1473-3099(19)30446-3  PMID: 31519541 
  5. Johannesen TB, Munkstrup C, Edslev SM, Baig S, Nielsen S, Funk T, et al. Increase in invasive group A streptococcal infections and emergence of novel, rapidly expanding sub-lineage of the virulent Streptococcus pyogenes M1 clone, Denmark, 2023. Euro Surveill. 2023;28(26):2300291.  https://doi.org/10.2807/1560-7917.ES.2023.28.26.2300291  PMID: 37382884 
  6. Davies MR, Keller N, Brouwer S, Jespersen MG, Cork AJ, Hayes AJ, et al. Detection of Streptococcus pyogenes M1UK in Australia and characterization of the mutation driving enhanced expression of superantigen SpeA. Nat Commun. 2023;14(1):1051.  https://doi.org/10.1038/s41467-023-36717-4  PMID: 36828918 
  7. The European Committee on Antimicrobial Susceptibility Testing (EUCAST). Breakpoint tables for interpretation of MICs and zone diameters. Version 13.0. Växjö: EUCAST; 2023. Available from: http://www.eucast.org
  8. de Gier B, Marchal N, de Beer-Schuurman I, Te Wierik M, Hooiveld M, de Melker HE, et al. Increase in invasive group A streptococcal (Streptococcus pyogenes) infections (iGAS) in young children in the Netherlands, 2022. Euro Surveill. 2023;28(1):2200941.  https://doi.org/10.2807/1560-7917.ES.2023.28.1.2200941  PMID: 36695447 
  9. Guy R, Henderson KL, Coelho J, Hughes H, Mason EL, Gerver SM, et al. Increase in invasive group A streptococcal infection notifications, England, 2022. Euro Surveill. 2023;28(1):2200942.  https://doi.org/10.2807/1560-7917.ES.2023.28.1.2200942  PMID: 36695450 
  10. Santé publique France. Situation des infections invasives à streptocoque A en France au 26 mars 2023. [Status of invasive streptococcal A infections in France as of March 26, 2023]. Paris: Santé publique France; 2023. French. Available from: https://www.santepubliquefrance.fr/docs/situation-des-infections-invasives-a-streptocoque-a-en-france-au-26-mars-2023
  11. Health Protection Surveillance Centre (HPSC). Update on Group A Streptococcus. Dublin: HPSC. [Accessed: 29 May 2023]. Available from: https://www.hpsc.ie/news/title-22663-en.html
  12. European Centre for Disease Prevention and Control (ECDC). Communicable disease threats report, 7-13 May 2023, week 19. 2023. Stockholm: ECDC; 2023. Available from: https://www.ecdc.europa.eu/en/publications-data/communicable-disease-threats-report-7-13-may-2023-week-19
  13. Barnes M, Youngkin E, Zipprich J, Bilski K, Gregory CJ, Dominguez SR, et al. Notes from the field: increase in pediatric invasive Group A Streptococcus Infections — Colorado and Minnesota, October–December 2022. MMWR Morb Mortal Wkly Rep. 2023;72(10):265-7.  https://doi.org/10.15585/mmwr.mm7210a4  PMID: 36893049 
  14. Cobo-Vázquez E, Aguilera-Alonso D, Carrasco-Colom J, Calvo C, Saavedra-Lozano J, Calvo C, et al. Increasing incidence and severity of invasive group A streptococcal disease in Spanish children in 2019-2022. Lancet Reg Health Eur. 2023;27:100597.  https://doi.org/10.1016/j.lanepe.2023.100597  PMID: 36895202 
  15. United Kingdom Health Security Agency. Group A streptococcal infections: 14th update on seasonal activity in England. London: Gov.uk. [Accessed: 29 May 2023]. Available from: https://www.gov.uk/government/publications/group-a-streptococcal-infections-activity-during-the-2022-to-2023-season/group-a-streptococcal-infections-14th-update-on-seasonal-activity-in-england
  16. van Kempen EB, Bruijning-Verhagen PCJ, Borensztajn D, Vermont CL, Quaak MSW, Janson JA, et al. Increase in invasive group A streptococcal infections in children in the Netherlands, a survey among 7 hospitals in 2022. Pediatr Infect Dis J. 2023;42(4):e122-4.  https://doi.org/10.1097/INF.0000000000003810  PMID: 36728741 
  17. Instituto Nacional de Saúde Doutor Ricardo Jorge (INSA). Boletim de vigilância epidemiológica da gripe e outros vírus respiratórios (Semana 30 – 24 a 30 jul). [Bulletin of Influenza Epidemiological Surveillance (Week 30 – 24 to 30 Jul)]. Lisbon: INSA; 2023. Available from: https://www.insa.min-saude.pt/category/informacao-e-cultura-cientifica/publicacoes/atividade-gripal
  18. Friães A, Pinto FR, Silva-Costa C, Ramirez M, Melo-Cristino J, Portuguese Group for the Study of Streptococcal Infections. Group A streptococci clones associated with invasive infections and pharyngitis in Portugal present differences in emm types, superantigen gene content and antimicrobial resistance. BMC Microbiol. 2012;12(1):280.  https://doi.org/10.1186/1471-2180-12-280  PMID: 23181337 
  19. Friães A, Melo-Cristino J, Ramirez M, Vaz T, Gião M, Ferreira R, et al. Changes in emm types and superantigen gene content of Streptococcus pyogenes causing invasive infections in Portugal. Sci Rep. 2019;9(1):18051.  https://doi.org/10.1038/s41598-019-54409-2  PMID: 31792274 
  20. Silva-Costa C, Ramirez M, Melo-Cristino J, Portuguese Group for Study of Streptococcal Infections. Declining macrolide resistance in Streptococcus pyogenes in Portugal (2007-13) was accompanied by continuous clonal changes. J Antimicrob Chemother. 2015;70(10):2729-33.  https://doi.org/10.1093/jac/dkv182  PMID: 26142474 

Data & Media loading...

Supplementary data

Submit comment
Comment moderation successfully completed
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error