The prevalence of Mycoplasma pneumoniae and study of co-infection with COVID-19 from a laboratory perspective, before and after the relaxation of COVID-19 control measures

Describe the prevalence of Mycoplasma pneumoniae (MP) in 2023, and investigate the influence of the relaxaion of COVID-19 pandemic control measures on MP prevalence. Analyze the positivity rates of MP in three distinct testing panels, assess clinical preferences for selecting these packages. Describe the co-infection status of MP with other respiratory pathogens, along with the laboratory characteristics of MP co-infection with COVID-19. Analyse the disparities in data between co-infected patients, healthy controls, and MP-only positive patients in terms of laboratory results, and speculate on its potential clinical implications. We retrospectively collected and analyzed MP epidemiological and clinical data from 2022-2023 using three MP-related tests. The results showed that a total of 37,017 MP-related tests were conducted, with an overall positivity rate of 2.03%. Among the positive cases, 83.36% were aged 0-15 years. In 2023, there were 628 tests for MP and Chlamydia pneumoniae (CP) Nucleic Acid Test, with a positivity rate of 19.11%, surpassing the 347 cases in 2022, which had a positivity rate of 5.76%. Influenza A virus was the most commonly co-infected respiratory pathogen with MP. The laboratory results of the control, single-infection, and co-infection groups showed that in the complete blood count (CBC), COVID-19 may have altered the immune process of MP. The main reason for the abnormal biochemical results in both single and double-positive groups was insufficient nutrition, leading to reduced synthesis. The urinalysis results indicated that the double-positive group had higher renal pressure than the single-positive group. MP entered the epidemic period in July following the relaxation of COVID-19 pandemic control measures. Additionally, COVID-19 may have altered the immune process of MP, impacting certain liver, heart, and kidney functions, as indicated by the laboratory results. Therefore, this study provides significant reference data for the clinical diagnosis and treatment of MP infections and co-infections with COVID-19.