Serotypes and genotypes of Streptococcus pneumoniae isolates from Trinidad and Tobago

Abstract

SUMMARYObjectivesThere are currently 94 known pneumococcal capsular polysaccharide serotypes and their prevalence differs by geographic region and the period studied. Streptococcus pneumoniae infections have been diagnosed clinically in Trinidad and Tobago and other Caribbean countries, however data on the serotype and sequence type distributions in this country are limited. The objective of this study was to determine serotypes and multilocus sequence types (MLSTs) of invasive and non-invasive pneumococcal isolates from Trinidad and Tobago.MethodsNinety-eight pneumococcal isolates from several regional hospitals in the country were analyzed using both standard microbiological methods and molecular analysis. These isolates included invasive (n = 83) and selected non-invasive (n = 15) strains recovered before (n = 25) and after (n = 73) the introduction of the pneumococcal conjugate vaccine.ResultsMore than half of the isolates (54.1%) were recovered from children under 15 years of age, with the largest proportion being from children under 2 years of age (24.5%). The most prevalent serotypes were 19F (18.4%), 6B (15.3%), 23F (14.3%), 3 (11.2%), 19A (6.1%), 6A (5.1%), 14 (5.1%), and 9V (4.1%). The most common serotype/MLST combinations were 6B/ST138 (n = 10, 10.2%), 3/ST180 (n = 5, 5.1%), 23F/ST629 (n = 5, 5.1%), 19F/ST8398 (n = 4, 4.1%), and three each of 6B/ST145, 14/9V/ST156, 9V/ST162, 19A/320, and 3/ST10440.ConclusionsThis report provides the first glimpse of the prevailing pneumococcal sequence types in the country. Most of the isolates represented serotypes in the 10-valent (61.2% of isolates) and 13-valent (83.7%) pneumococcal conjugate vaccines. A detailed population study is warranted to fully determine the circulating pneumococcal sequence types. Furthermore, the implementation of an effective and continuous surveillance system in Trinidad and Tobago is paramount to monitor vaccine impact.

Characterization of Pneumococcal Colonization Dynamics and Antimicrobial Resistance Using Shotgun Metagenomic Sequencing in Intensively Sampled South African Infants

“…Serotypes 15B/15C and 16F were the predominant serotypes detected in our cohort, and highly prevalent serotypes tend to be more diverse (47). No other ST was associated with more than one serotype, in line with previous observations (48).…”

Characterization of Blood-isolated, Penicillin-Nonsusceptible Streptococcus pneumoniae From Children Between 2014 and 2018 in Bojnurd, Iran

“…It should be noted that regardless of antimicrobial resistance, the most prevalent serotypes among our isolates were 19A, 6A/B, 1, 23F, 19F, 14, 15B/C, and 15A, respectively. In a similar study in Trinidad and Tobago, the most prevalent serotypes among invasive isolates were 19F, 6B, 23F, 3, 19A, 6A, 14, and 9V, respectively (33). In another study in China, the most common serotypes were 19F, 19A, 15, 6B, 6A, and 17 (34).…”

Association Between Pneumococcal Surface Protein A Family and Genetic/Antimicrobial Resistance Traits of Non-Invasive Pneumococcal Isolates from Adults in Northern Japan

“…[38][39][40] This serotype was mainly isolated from IPD adult patients from pre-PCV to post-PCV period. 41 In Greece, serotype 3 accounted for 33% in isolates obtained from PCV13vaccinated children, 42 while in Portugal its prevalence in children did not show a significant change. 43 A study conducted in Japan indicated a significantly lower antibody response to serotype 3 in the PCV13-than in PPSV23-vaccinated group.…”