Co-Detection of ADV, Influenza B, and HPIV: Independent Risk Factors for SMPP with Changes in NPIs.

Background: This study investigated the epidemiology of Mycoplasma pneumoniae (MP) in children with acute respiratory tract infections (ARTIs) and explored the risk factors for severe mycoplasma pneumoniae pneumonia (SMPP) in children. Methods: A retrospective analysis was conducted on 36,380 children with acute respiratory infections who underwent multiplex real-time polymerase chain reaction (RT-PCR) assays for nine respiratory pathogens from September 2021 to November 2024. Results: A total of 36,380 children with ARTIs were enrolled in this study. The co-detection rate of MP with other pathogens was significantly higher in the post-NPIs period than in the NPIs period (36.5% vs. 25.7%, p < 0.01). Multivariate regression identified the detection of influenza A virus (InfA), InfB, human parainfluenza virus (HPIV), human bocaparvovirus (HBoV), human rhinovirus (HRV), adenovirus (ADV), human respiratory syncytial virus (HRSV), and human metapneumovirus (HMPV) as protective factors against MP epidemics (p < 0.01); meanwhile, older age, the cancellation of NPIs, and summer-autumn seasons were found to be risk factors. After adjusting for sex, age, period, season, and pathogens, InfB (OR: 3.009, 95%CI: 1.041-8.697, p = 0.042), HPIV (OR: 2.226, 95%CI: 1.170-4.235, p = 0.015), and ADV (OR: 2.035, 95%CI: 1.105-3.750, p = 0.023) were identified as independent risk factors for SMPP. Conclusions: These findings highlight post-NPI shifts in MP epidemiology and identify ADV, InfB, and HPIV as early warning markers for SMPP.