Serotype and drug resistance of 192 isolates of Streptococcus pneumoniae, a study in Zhongjiang County People's Hospital, Sichuan

  Objective  To analyze the serotype distribution and drug resistance of Streptococcus pneumoniae isolated from hospitalized patients in all age groups in Zhongjiang, Sichuan province.

  Methods  From November 2018 to June 2019, we collected 192 isolates of S. pneumoniae for serotypes identification using Quellung reaction. Antibiotic resistance was tested using E-test or disc diffusion method.

  Results  A total of 26 serotypes of S. pneumoniae were identified in 192 isolates. The most common serotype was 19A (41, 21.35%), followed by 19F (37, 19.27%), 6B (17, 8.85%), 23F (15, 7.81%), 16F (12, 6.25%) and 15A (11, 5.73%). The coverage of PCV13 was 67.19% and the coverage of PPV23 was 68.20%. With the increase of age, the proportion of PCV13 type decreased significantly from 78.05% in age group <2 years to 44.00% in age group ≥60 years, the difference was significant. The intermediate rate and resistance rate of the isolates to oral penicillin were 56.20% and 39.60%, respectively. The resistance rate to erythromycin was high (92.43%). The PCV13 isolates were more resistant to penicillin than the non-PCV13 isolates.

  Conclusion  The coverage rateof PCV13 in Streptococcus pneumoniae clinical isolates from Zhongjiang County, Sichuan Province is low and decreases with the increase of host age. Adults, especially the elderly, may be non-PCV13 repository.