Streptococcus pneumoniae is the major cause of childhood
pneumonia and related deaths in India. Widespread use of
erythromycin for the treatment of
pneumonia has led to the emergence of
erythromycin resistance. Despite this increase in
erythromycin resistance, there are very little data on resistance determinants from India. Hence, we aimed to perform the molecular characterization of
erythromycin-resistant invasive pneumococcal isolates in India. In this study, 250
erythromycin-resistant invasive isolates obtained from four Indian hospitals between 2014 and 2019 were included. The isolates were reconfirmed by standard CDC protocols, followed by detection of erm(B), mef(A/E) genes, and screening for mutations in
23S rRNA,
ribosomal proteins L4 and L22. Among the 250
erythromycin-resistant isolates, 46% (n = 114) and 35% (n = 87) carried the mef(A/E) gene and erm(B) gene, respectively; both genes were present in 8% (n = 20) of the isolates and 12% (n = 29) of the studied strains did not bear any of them. The major mutations associated with
erythromycin resistance in
23S rRNA, such as A2060C, A2061G, and C2613G, were absent. The predominant serotypes were 19F, 14, 23F, 6A, 6B, 19A, and 9V. The major clonal complexes were CC320, followed by CC230 and CC63. The predominant gene was mef(A/E), and most of the serotypes were PCV13 (54%). This study contributes to the baseline understanding of the
erythromycin resistance determinants associated with the serotypes and sequence types (ST) of Indian invasive S. pneumoniae.