Mycoplasma pneumoniae Infections Among Children and Adolescents in Korea, 2014-2024.

BACKGROUND

Mycoplasma pneumoniae (MP) is the most common cause of community-acquired bacterial pneumonia in children. Macrolides are used as the first-line treatment for MP infection, but resistance has increased significantly over the past few decades, making treatment difficult. This study examines the prevalence of M. pneumoniae infections and macrolide-resistant M. pneumoniae (MRMP) rates in Korean children across three recent epidemics in Korea between 2014 and 2024.

METHODS

Data from Green Cross Laboratories on M. pneumoniae polymerase chain reaction (PCR) and macrolide-resistance tests were analyzed from January 2014 to March 2024, including 425,079 MP PCR tests and 11,206 resistance tests (macrolide-resistance testing began in 2019). We examined M. pneumoniae-positive rates by age and compared age composition to the epidemic and non-epidemic periods using Cochran-Armitage trend tests and also examined differences in MRMP positive rates by year, epidemic status, sex, age group, and region using the χ² test.

RESULTS

Three epidemics of M. pneumoniae infection were identified in 2015/16, 2019/20, and 2023/24, with seasonal peaks between the third and fourth quarter of each starting epidemic year and the highest M. pneumoniae-positive rates in children aged 7 to 9 years. There were significant differences in the proportion of children aged 12 years or younger between epidemic and non-epidemic periods (P < 0.001 for two epidemics and 0.027 for one). MRMP PCR positive rates for A2063G and A2064G mutations were 76.6% and 0.7%, respectively, with a notable increase in A2063G rates from 2019/20 to 2023/24, along with a significant decrease as age increased.

CONCLUSION

The findings indicate a significant rise in M. pneumoniae infections among Korean children, especially those aged 12 years or younger, suggesting a nationwide epidemic. The increase in A2063G mutation rates underscores the need for monitoring antibiotic resistance and further research into resistance factors for future epidemic responses.