Macrolide-resistant infection in children observed during a period of high incidence in Henan, China.

Objective: (Mp) is one of the major pathogens that causes respiratory tract infections, and macrolide resistance has increased rapidly in recent years due to the inappropriate use of macrolides in northeastern Asia. In the present study, we aimed to investigate Mp infection and macrolide resistance during a period of high incidence of Mp infection in Henan, China.

Methods: A total of 29473 suspected children with Mp infection were enrolled in the study from July to December 2023. Throat swab specimens were collected from all the study subjects, and real-time PCR was performed to detect the Mp-DNA and macrolide resistance-associated A2063G or A2064G mutations.

Results: The overall percentage of Mp-DNA-positive patients was 51.1 %, and the percentage of macrolide-resistant strains was 91 %. The rate of macrolide resistance remained stable from July to December. The Mp-DNA positivity rates among the different age groups from low to high were 0-1, 1-3, 3-6, 10-18 and 6-10 years. The macrolide resistance rate was the lowest in the 0-1 age group and highest in the 6-10 age group. No difference in the rate of macrolide resistance was observed between male and female children.

Conclusions: The macrolide resistance rate of Mp did not change during the investigated period of high incidence of infection, and no sex difference existed. The macrolide resistance rate of Mp was the lowest in children under 1 year old.