COVID-19 Pandemic Alters Mycoplasma Pneumoniae Infections in Tianjin, China's Pediatric Population

Researchers from Tianjin University conducted a study to investigate the epidemiological characteristics and temporal-spatial distribution of Mycoplasma pneumoniae (MP) infections among pediatric inpatients with respiratory tract infections in Tianjin, China, across three distinct phases: pre-pandemic (2017-2019), pandemic (2020-2022), and post-pandemic (2023-2024). The primary hypothesis was that the COVID-19 pandemic altered the epidemiology of MP infections in children. The study analyzed data from 60,213 pediatric patients hospitalized with respiratory infections between January 2017 and December 2024, with a male-to-female ratio of 1.22:1.00.

Key Takeaways:

  • The overall positive detection rate of MP-RNA among children hospitalized for respiratory infections during the study period was 36.58% (22,023/60,213).
  • The annual MP-RNA-positive detection rates from 2017 to 2024 were 50.74% (411/810) in 2017, 36.28% (1,150/3,170) in 2018, 27.41% (1,459/5,323) in 2019, 10.18% (222/2,181) in 2020, 11.42% (928/8,129) in 2021, 13.27% (579/4,364) in 2022, 28.97% (3,064/10,575) in 2023, and 55.38% (14,210/25,661) in 2024.
  • The highest annual positivity rate was observed in 2024 (55.38%, 14,210/25,661), while the lowest rate occurred in 2020 (10.18%, 222/2,181).
  • Statistical analysis revealed significant differences in MP-RNA detection rates across different years (χ²=8331.511, p < 0.001).
  • The COVID-19 pandemic substantially altered MP epidemiology in Tianjin's pediatric population, with infection rates demonstrating a U-shaped trajectory across pandemic phases.
  • School-aged children and females exhibited heightened susceptibility to MP infections.
  • Epidemiological surveillance should be incorporated into diagnostic algorithms for childhood respiratory infections, particularly in post-pandemic settings.

Statistics:

  • 60,213 pediatric patients hospitalized with respiratory infections between January 2017 and December 2024.
  • Male-to-female ratio of 1.22:1.00.
  • Overall positive detection rate of MP-RNA: 36.58% (22,023/60,213).
  • Annual MP-RNA-positive detection rates:

+ 2017: 50.74% (411/810)

+ 2018: 36.28% (1,150/3,170)

+ 2019: 27.41% (1,459/5,323)

+ 2020: 10.18% (222/2,181)

+ 2021: 11.42% (928/8,129)

+ 2022: 13.27% (579/4,364)

+ 2023: 28.97% (3,064/10,575)

+ 2024: 55.38% (14,210/25,661)

  • χ² test: 8331.511, p < 0.001.

Sources:

  • Epidemiological association of the COVID-19 pandemic on Mycoplasma pneumoniae infections in children in Tianjin, China: a single-centre retrospective study (2017-2024). BMJ Open, 2025, 15(6).
  • Tianjin University. Academy of Medical Engineering & Translational Medicine. Tianjin, People's Republic of China.
  • BMJ Publishing Group. Publisher of BMJ Open.
  • NewsRx LLC. Medical Letter on the CDC & FDA. July 6, 2025; p 144.