OBJECTIVETo study the epidemiological characteristics of Mycoplasma pneumoniae pneumonia (MPP) in children, and to provide a basis for diagnosis and treatment.

METHODSThe serum level of Mycoplasma pneumoniae antibody IgM (MP-IgM) was measured by enzyme-linked immunosorbent assay for 3156 hospitalized children with confirmed community acquired pneumonia from February 2011 to January 2012. The antigens of seven respiratory viruses were detected in the nasopharyngeal secretions of children with MPP.

RESULTSMP-IgM was detected in 427 of the 3156 patients, with a positive rate of 13.53%. The infection rate in female patients was significantly higher than in male patients (16.30% vs 11.70%; P<0.01). The MP-IgM detection rates were 3.6%, 12.5%, 19.2%, and 24.4% in children aged under 1 year, 1-3 years, 3-6 years and 6-14 years respectively (P<0.01), and the total MP-IgM detection rate in children aged under 3 years was significantly lower than in children over 3 years (P<0.01). The MP-IgM detection rate varied with the seasons and was significantly higher in summer and autumn than in winter and spring (19.18% vs 9.61%; P<0.01). Of the 427 MP-IgM-positive children, 60 (14.1%) were infected with respiratory viruses, and the highest proportion of which was respiratory syncytial virus.

CONCLUSIONSMPP is sporadic throughout the whole year, with a higher incidence in summer and autumn. MPP occurs mostly in preschool and school-age children, and there is mixed infection of MP and respiratory viruses.