Phân bố type huyết thanh, tần suất mang gen erm(B) và mef(A) ờ các chủng Streptococcus pneumoniae kháng macrolide thu thập từ trẻ dưới 5 tuổi bị viêm phổi tại Nghệ An

This study aims to determine the serotypes and frequency of carrying erm(B) and mef(A) genes in macrolide antibiotic-resistant pneumococcal strains collected from children under 5 years old with pneumonia in Nghe An. Methods: It was a descriptive cross-sectional study on 126 pneumococcal strains from November 2019 to December 2021. Results: Eight serotypes 6A/B, 9V, 11A, 14, 15A, 19F, 19A, and 23F were identified in Nghe An, of which serotype 19A accounts for a high proportion. The presence of erm(B) and mef(A) genes was determined by PCR reactions, the frequency of carrying erm(B) and mef(A) genes was 92.1% and 57.9%, respectively. The frequency of carrying at least one of these two genes is 95.3% and the frequency of carrying two genes simultaneously is 54.8%. There are 6 macrolide antibiotic-resistant strains that do not carry any of the erm(B) and mef(A) genes, accounting for 4.8%. Conclusion: Eight different serotypes of pneumococcus were identified in Nghe An. 19F, 23F and 19A are the most common. Serotype 19A with its high infection rate is a feature that needs attention. The frequency of carrying the erm(B) and mef(A) genes is 92.1 and 57.9%, respectively.