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Published on: September 11, 2020
Characterization of Streptococcus pneumoniae isolates from India with special reference to their sequence types
Malini Shariff1, Jyoti Choudhary, Shazia Zahoor
1Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India . malini.shariff@gmail.com
Journal of Infection in Developing Countries
|February 19, 2013
Summary
This study identified key Streptococcus pneumoniae serotypes in India, with many not covered by current vaccines. An updated vaccine is crucial for effective disease prevention in the region.
Area of Science:
- Microbiology
- Epidemiology
- Public Health
Background:
- Streptococcus pneumoniae causes significant mortality and morbidity, particularly in vulnerable populations.
- Pneumococcal infections pose a substantial global health burden.
Purpose of the Study:
- To characterize antimicrobial susceptibilities, serotypes, and sequence types of pneumococcal isolates from New Delhi, India.
- To inform public health strategies and vaccine development for Streptococcus pneumoniae in the region.
Main Methods:
- Disk diffusion and broth microdilution assays for antimicrobial susceptibility testing.
- Serotyping and multilocus sequence typing (MLST) for isolate characterization.
Main Results:
- High resistance rates observed: 5% to penicillin, 20% to erythromycin, and 23% to ciprofloxacin.
- Predominant serotypes included 19, 1, and 6; 30% of isolates belonged to non-seven-valent vaccine serotypes (1, 3, 5, 19A, 7F).
- MLST revealed significant genetic diversity with 30 new sequence types (STs) and 11 clonal complexes among 115 Indian isolates; only 4 STs were globally prevalent.
Conclusions:
- The study highlights the circulation of non-vaccine serotypes of Streptococcus pneumoniae in India.
- An appropriate vaccine covering prevalent local serotypes is essential for effective disease control in the region.
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