Objective To analyze the incidence rate and spatio-temporal as well as population distribution characteristics of Mycoplasma pneumoniae (MP) infections in Jinhua City, and provide an evidence-based basis for targeted regional prevention and control of MP infections.

Methods MP infection detection data and permanent population data of Jinhua City from 2023 to 2024 were collected. Data were extracted and cleaned using SQL algorithm (duplicate records were excluded), and positive cases were identified in accordance with laboratory standards. Software including R studio and JoinPoint 5.0.2 was used to analyze the epidemiological characteristics of MP infections through chi-square test, JoinPoint regression, spatial autocorrelation analysis, and Poisson spatio-temporal scan statistic model. Relative risk (RR) and 95% confidence interval (CI) were used to evaluate the infection risk, with a significance level of α=0.05.

Results A total of 156,062 positive MP infection cases were reported in Jinhua City from 2023 to 2024, with an average annual incidence rate of 1,092.13 per 100,000 population. The incidence rate in 2024 (995.72 per 100,000 population) decreased significantly compared with that in 2023 (1,189.03 per 100,000 population) (χ²=1,235.838, P<0.001). Temporally, the epidemic peak occurred from November 2023 to January 2024. Three inflection points were identified by JoinPoint regression: the incidence rate increased rapidly from September to December 2023 (Annual Percent Change, APC=85.04%, P=0.040) and decreased significantly from January to June 2024 (APC=−30.04%, P=0.041). Spatially, Yiwu City, Dongyang City, and Yongkang City were high-incidence areas (average annual incidence rate >1,200 per 100,000 population). MP infections showed significant positive spatial correlation (Moran’I=0.138, P=0.003), with local high-high aggregation areas concentrated in 6 streets of Dongyang City and Yiwu City. Six high-risk areas were identified by spatio-temporal scan, among which the northeastern aggregation area from November 2023 to January 2024 had the highest risk (RR=4.58, Log Likelihood Ratio, LLR=24,342.12, P<0.001). In terms of population distribution, the incidence rate in females (1,158.34 per 100,000 population) was higher than that in males (1,032.86 per 100,000 population) (χ²=259.561, P<0.001). The 5−9 years old group had the highest incidence rate (7,573.02 per 100,000 population). Males aged 25-44 years had significantly lower infection risk than females (RR=0.46, P<0.001), while males aged ≥65 years had higher risk than females (RR=1.52, P<0.001).

Conclusion The MP infections in Jinhua City presents a significant seasonal fluctuations, spatial aggregation, and population heterogeneity. Children aged 5−9 years and the regions of Yiwu City, Dongyang City, and Yongkang City are the key targets for MP infection prevention and control. The research findings provide data support for formulating region-specific and population-specific targeted prevention and control strategies.