Emergence of serotype 19AStreptococcus pneumoniaeafter PCV10 associated with a ST320 in adult population, in Porto Alegre, Brazil

Abstract

Use of pneumococcal conjugate vaccines has caused emergence of non-vaccine serotypes. No Brazilian data specifically about serotype 19A are available. We aimed to evaluate the frequency of occurrence, susceptibility profile and molecular epidemiology of serotype 19A before and after vaccine introduction in Brazil. Pneumococcal identification was performed by the conventional method. Strain serotype was determined by multiplex polymerase chain reaction (PCR) and/or Quellung reaction. Resistance was determined by Etest® and PCR was performed to determine the presence of macrolide resistance genes, ermB and/or mefA. Pneumococci were typed by Multilocus Sequence Typing. Thirty-eight serotype 19A Streptococcus pneumoniae were recovered, mostly from invasive diseases. Prevalence of serotype 19A increased following vaccination (from 3.5% before vaccination to 8.1% after, p = 0.04196). Non-susceptibility increased to most antimicrobials after vaccine introduction and was associated with clonal complex (CC)320. MLST showed nine different STs, which were grouped in one main CC: CC320 (63.9%). During the post-vaccination era, the frequency of this serotype increased significantly from 1.2% in 2011 to 18.5% in 2014 (p = 0.00001), with a concomitant decrease in the genetic variability: ST320 consistently predominated after vaccine-introduction (61.1%). Overall, our results showed a post-PCV10 increase in the frequency of serotype 19A. This was accompanied by a selection of CC320 and antimicrobial resistance.

Pneumococcal Diseases Caused by Serotype Replacement in Colombia: A Cost-Effectiveness Analysis of Pneumococcal Conjugate Vaccines in Infants and Its Herd Protection in Older Adults

“…(19) Other Latin-American countries have observed similar phenomenon, which non-vaccinal serotypes grow in isolated of IPD. A study carried up in Porto Alegre (Brazil) reported changes in percentage of 19A serotype from 1.2% in 2011 to 18.5% in 2014 (56). Other study in Brazil analyzing the laboratorybased surveillance reported the changes from 3.2% in the period early-post -PCV10to 9.3% ve years after (57).…”

Circulating Clonal Complexes and Sequence Types of Streptococcus Pneumoniae Serotype 19a Worldwide: The Importance of Multidrug Resistance: A Systematic Literature Review

“…In total, 12 records were identified from the Americas: 8 from North America [22][23][24][25][26][27][28][29] and 4 from South America [30][31][32][33] (Table 1).…”

Cost-effectiveness analysis of replacing the 10-valent pneumococcal conjugate vaccine (PCV10) with the 13-valent pneumococcal conjugate vaccine (PCV13) in Brazil infants

“…The 10-valent (PCV10) was introduced universally for all children 0–2 y of age as a 3 + 1 schedule in 2010 and later changed to 2 + 1 schedule in 2016. 5 In 2019, PCV13 was approved in Brazil’s NIP exclusively for patients over 5 y of age with high-risk conditions.…”

“…2 , 6 In 2018, approximately 40% of all registered IPD cases in children under 5 y were caused by serotype 19A and 52.3% were attributed to serotype 3, 6A, and 19A combined. 5 The editorial report from the Board of Directors of the Latin American Pediatric Association (ALAPE) revealed Latin American countries incorporating PCV10 in pediatric NIPs (Brazil, Chile, Paraguay, Peru, and Colombia) have subsequently experienced increases in serotype 19A. 7 Moreover, a recent World Health Organization (WHO) position regarding PCVs in 2019 advises that the choice of the appropriate vaccine in a country should be based on, among other factors, local and regional prevalence of serotypes and antimicrobial resistance patterns.…”