Affiliation:
1. Department of Microbiology, College of Medicine, Kuwait University, P.O. Box 24923, Safat 13110, Kuwait
Abstract
Background: Multilocus sequence typing (MLST) is used to gain insight into the population genetics of bacteria in the form of sequence type (ST). MLST has been used to study the evolution and spread of virulent clones of Streptococcus pneumoniae in many parts of the world. Such data for S. pneumoniae are lacking for the countries of the Arabian Peninsula, including Kuwait. Methods: We determined the STs of all 31 strains of S. pneumoniae from invasive diseases received at a reference laboratory from various health centers in Kuwait during 2018 by MLST. The relationship among the isolates was determined by phylogenetic analysis. We also determined the serotypes by Quellung reaction, and antimicrobial susceptibility by Etest, against 15 antibiotics belonging to 10 classes. Results: There were 28 STs among the 31 isolates, of which 14 were new STs (45.2%) and 5 were rare STs (16.1%). Phylogenetic analysis revealed that 26 isolates (83.9%) were unrelated singletons, and the Kuwaiti isolates were related to those from neighboring countries whose information was gleaned from unpublished data available at the PubMLST website. Many of our isolates were resistant to penicillin, erythromycin, and azithromycin, and some were multidrug-resistant. Virulent serotype 8-ST53, and serotype 19A with new STs, were detected. Conclusions: Our study detected an unusually large number of novel STs, which may indicate that Kuwait provides a milieu for the evolution of novel STs. Novel STs may arise due to recombination and can result in capsular switching. This can impact the effect of vaccination programs on the burden of invasive pneumococcal disease. This first report from the Arabian Peninsula justifies the continuous monitoring of S. pneumoniae STs for the possible evolution of new virulent clones and capsular switching.
Subject
Virology,Microbiology (medical),Microbiology
Reference43 articles.
1. Current trends in Streptococcus pneumoniae infections and their treatment;Shetty;Curr. Pediatr. Rep.,2013
2. World Health Organization (2018). Surveillance Vaccine Preventable. Pneumococcus, World Health Organization.
3. Increasing prevalence of antimicrobial resistance in Streptococcus pneumoniae in Kuwait: Implications for therapy;Mokaddas;Microb. Drug Resist.,2007
4. Serotype distribution and penicillin non-susceptibility of Streptococcus pneumoniae causing invasive diseases in Kuwait: A 10-year study of impact of pneumococcal conjugate vaccines;Mokaddas;Expert Rev. Vaccines,2016
5. Ganaie, F., Saad, J.S., McGee, L., van Tonder, A.J., Bentley, S.D., Lo, S.W., Gladstone, R.A., Turner, P., Keenan, J.D., and Breiman, R.F. (2020). A new pneumococcal capsule type, 10D, is the 100th serotype and has a large cps fragment from an oral streptococcus. mBio, 11.