Caierão Juliana, Hawkins Paulina, Sant'anna Fernando Hayashi, da Cunha Gabriela Rosa, d'Azevedo Pedro Alves, McGee Lesley, Dias Cícero
Federal University of Health Science of Porto Alegre, Rio Grande do Sul, Brazil.
Emory University, Atlanta, Georgia, United States of America.
PLoS One. 2014 Oct 30;9(10):e111129. doi: 10.1371/journal.pone.0111129. eCollection 2014.
To reduce the burden of pneumococcal diseases, different formulations of pneumococcal conjugate vaccines (PCV) have been introduced in many countries. In Brazil, PCV10 has been available since 2010. We aimed to analyze the serotype and genetic composition of invasive pneumococci from Brazil in pre- and post-vaccination periods (2007-2012). Antibiotic susceptibility was determined and genotypes of macrolide and fluoroquinolone resistance were characterized. The genotypes of isolates of the most frequent serotypes were determined by multilocus sequence typing. The study included 325 isolates, which were primarily recovered from blood. The most common serotypes recovered were 14, 3, 4, 23F, 7F, 9V, 12F, 20, 19F, 8, 19A, and 5. Thirty-eight pneumococci (11.7%) were from children ≤5 years old. Considering the overall population, PCV10 and PCV13 serotype coverage was 50.1% and 64.9%, respectively. During the pre-vaccine period, isolates with serotypes belonging to the PVC10 represented 51.5% (100/194), whereas in the post vaccine they represented 48.0% (63/131). PCV13 serotypes represented 67.5% (131/194) and 59.2% (77/131) of total for pre- and post-vaccination periods, respectively. Seventy different sequence types [STs] were found, accounting for 9 clonal complexes [CCs] and 45 singletons. Eight STs (156, 180, 218, 8889, 53, 191, 770, and 4967) represented the majority (51.5%) of isolates. Fifty STs were associated with the pre-vaccination period (27 exclusive) and 43 (20 exclusive) with the post-vaccination period; 23 STs were identified in both periods. Some serotypes were particularly clonal (7F, 8, 12F, 20). Non-susceptibility to penicillin was associated with serotype 19A, CC320. Erythromycin resistance was heterogeneous when considering serotype and ST. A single serotype 23F (ST4967) isolate was resistant to levofloxacin. Continued surveillance is required to determine vaccine impact and to monitor changes in pneumococcal population biology post-PCV10 introduction in Brazil.
为减轻肺炎球菌疾病负担，许多国家已引入不同配方的肺炎球菌结合疫苗（PCV）。在巴西，自2010年起可获得PCV10。我们旨在分析巴西接种疫苗前后时期（2007 - 2012年）侵袭性肺炎球菌的血清型和基因组成。测定了抗生素敏感性，并对大环内酯类和氟喹诺酮类耐药的基因型进行了特征分析。通过多位点序列分型确定最常见血清型分离株的基因型。该研究包括325株分离株，主要从血液中分离得到。分离出的最常见血清型为14、3、4、23F、7F、9V、12F、20、19F、8、19A和5。38株肺炎球菌（11.7%）来自5岁及以下儿童。考虑总体人群，PCV10和PCV13血清型覆盖率分别为50.1%和64.9%。在疫苗接种前时期，属于PCV10的血清型分离株占51.5%（100/194），而在疫苗接种后占48.0%（63/131）。PCV13血清型在疫苗接种前和后时期分别占总数的67.5%（131/194）和59.2%（77/131）。发现了70种不同的序列类型[STs]，占9个克隆复合体[CCs]和45个单倍型。8种STs（156、180、218、8889、53、191、770和4967）占分离株的大多数（51.5%）。50种STs与疫苗接种前时期相关（27种为独有），43种（20种为独有）与疫苗接种后时期相关；两个时期共鉴定出23种STs。一些血清型具有特别的克隆性（7F、8、12F、20）。对青霉素不敏感与19A血清型、CC320相关。考虑血清型和ST时，红霉素耐药性存在异质性。单个23F血清型（ST4,967）分离株对左氧氟沙星耐药。需要持续监测以确定疫苗影响，并监测巴西引入PCV10后肺炎球菌群体生物学的变化。
