ObjectivesTo investigate the prevalence of mycoplasma pneumonia (MP) in the pediatric outpatient department of Shanghai Pudong New District Zhoupu Hospital and its relationship with the concentration of fine particulate matter (PM 2.5) in the air.MethodsPatients with respiratory tract infection, from one month to 15 years old, diagnosed in the pediatric department of Shanghai Pudong New District Zhoupu Hospital from May 2016 to April 2017 were enrolled. Mycoplasma pneumonia antibody was detected by colloidal gold assay, and mycoplasma antibody was detected after 1 week of negative test. PM 2.5 index of the same period was also collected. SAS 9.1.3 software was used for statistical analysis.ResultsA total of 3 862 children were enrolled, of which 947 were positive for MP, with a positive rate of 24.52%. The positive rates of each age group were 10.02% for the one month to one year old group, 23.51% for the 1 to 4 years old group, 31.70% for the 4 to 7 years old group, and 22.81% for the 7 to 15 years old group. The positive rate of each age group had statistically significant difference (χ2=86.120 0, P<0.000 1). The positive rates of spring, summer, autumn, and winter were 25.06%, 20.43%, 19.52 and 33.61%, respectively. The difference was statistically significant (χ2=67.1446, P<0.000 1). Combining the PM 2.5 index in Shanghai Pudong area from May 2016 to April 2017, the positive correlation between PM 2.5 and positive rate of MP was found (r=0.9007, P<0.001).ConclusionsThe positive rate of MP in Shanghai Pudong area is 24.52%, and reach its highest level in the preschool children and in winter. It is positively correlated with the PM 2.5 index as well.