Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru; Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima, Peru; Grupo Peruano de Investigación en Neumococo (GPIN), Lima, Peru.
Servicio de Pediatría de Especialidades Clínicas, Hospital Nacional Edgardo Rebagliati Martins, Lima, Peru; Grupo Peruano de Investigación en Neumococo (GPIN), Lima, Peru.
J Infect Public Health. 2024 Jan;17(1):44-50. doi: 10.1016/j.jiph.2023.10.047. Epub 2023 Nov 2.
The Pneumococcal conjugate vaccine (PCV) has decreased cases of invasive pneumococcal disease (IPD) worldwide. However, the impact of PCVs introduction may be affected by the serotype distribution in a specific context.
Cross-sectional multicenter passive surveillance study of IPD cases in pediatric patients hospitalized in Lima, Peru between 2016 and 2019 (after PCV13 introduction) to determine the serotype distribution and antimicrobial resistance of Streptococcus pneumoniae. Serotyping was performed by a sequential multiplex PCR and confirmed by whole genome sequencing.
Eighty-five S. pneumoniae isolates were recovered (4.07/100,000 among children <60 months of age). Serotype 19A was the most common (49.4%). Children infected with serotype 19A in comparison with children infected with other serotypes were younger, had a lower rate of meningitis and higher rates of pneumonia, complicated pneumonia and antimicrobial resistance; 28.6% of patients with serotype 19A have received at least one dose of PCV13 vs. 62.8% of patients with other serotypes. Using MIC-breakpoints, 81.2% (56/69) of non-meningitis strains and 31.2% (5/16) of meningitis strains were susceptible to penicillin; 18.8% (3/16) of meningitis strains had intermediate resistance to ceftriaxone. Resistance to azithromycin was 78.8% (67/85). Serotype 19A frequency increased over time in the same study population, from 4.2% (4/96) in 2006-2008, to 8.6% (5/58) in 2009-2011, to 49.4% (42/85) in the current study (2016-2019) (p < 0.001).
After PCV13 introduction in Peru, serotype 19A remains the most prevalent; however, the vaccination coverage is still not optimal. Therefore, additonal surveillance studies are needed to determine the remaining IPD burden.
肺炎球菌结合疫苗（PCV）已在全球范围内降低了侵袭性肺炎球菌病（IPD）的病例。然而，PCV 的引入效果可能会受到特定环境中血清型分布的影响。
2016 年至 2019 年期间，在秘鲁利马住院的儿科患者中进行了 IPD 病例的横断面多中心被动监测研究，以确定肺炎链球菌的血清型分布和抗生素耐药性。血清型通过顺序多重 PCR 进行检测，并通过全基因组测序进行确认。
共分离出 85 株肺炎链球菌（60 个月以下儿童中每 100,000 人 4.07 例）。血清型 19A 最为常见（49.4%）。与感染其他血清型的儿童相比，感染血清型 19A 的儿童年龄更小，脑膜炎发生率更低，肺炎、合并肺炎和抗生素耐药率更高；血清型 19A 患者中有 28.6%接受过至少一剂 PCV13，而感染其他血清型的患者中有 62.8%。使用 MIC 折点，81.2%（56/69）的非脑膜炎株和 31.2%（5/16）的脑膜炎株对青霉素敏感；16 株脑膜炎株中有 31.2%（5/16）对头孢曲松中介耐药。对阿奇霉素的耐药率为 78.8%（67/85）。在同一研究人群中，血清型 19A 的频率随时间推移而增加，从 2006-2008 年的 4.2%（4/96）增加到 2009-2011 年的 8.6%（5/58），再增加到 2016-2019 年的当前研究中的 49.4%（42/85）（p<0.001）。
在秘鲁引入 PCV13 后，血清型 19A 仍然最为普遍；然而，疫苗接种覆盖率仍然不理想。因此，需要进行额外的监测研究以确定剩余的 IPD 负担。
