Mycoplasma pneumoniae incidence, phenotype, and severity in children and adolescents in Denmark before, during, and after the COVID-19 pandemic: a nationwide multicentre population-based cohort study

• Published in: The Lancet regional health. Europe 2024-12, Vol.47, p.101103, Article 101103
• Main Authors: Dungu, Kia H.S., Holm, Mette, Hartling, Ulla, Jensen, Lise H., Nielsen, Allan Bybeck, Schmidt, Lisbeth S., Toustrup, Lise B., Hansen, Lotte H., Dahl, Kathrin W., Matthesen, Kirstine T., Nordholm, Anne C., Uldum, Søren, Emborg, Hanne-Dorthe, Rytter, Maren J.H., Nygaard, Ulrikka
• Format: Article
• Language: English
• Subjects: Corticosteroids; COVID-19; MIRM; Mycoplasma; Mycoplasma induced rash and mucositis; Mycoplasma pneumoniae; Mycositis; Reactive infectious mucocutaneous eruptions; Resurgence; RIME
• ISSN: 2666-7762; 2666-7762
• DOI: 10.1016/j.lanepe.2024.101103

Mycoplasma pneumoniae infections resurged globally in 2023–2024 after a three-year decline during the COVID-19 pandemic. We explored the incidence and severity of M pneumoniae infections in children and adolescents before, during, and after the pandemic. This nationwide, population-based cohort study included all Danish children and adolescents aged 0–17 years with a positive M pneumoniae PCR test from May 1, 2016, to April 30, 2024. We obtained clinical details for patients hospitalised for 24 h or more. Risk ratios for infections, hospitalisations, and disease manifestations in 2023–2024 versus pre-COVID-19 seasons were calculated using Fisher’s exact and Pearson’s χ2 tests. A season was defined from May 1 to April 30. Among the Danish population of 1,152,000 children and adolescents, 14,241 with a positive PCR test for M pneumoniae were included. In 2023–2024, children and adolescents with a positive PCR rose 2.9-fold (95% CI 2.8–3.1; p