Juscamayta-López Eduardo, Vega-Abad Betsabé, Valdivia Faviola, Soto María Pía, Horna Helen, García-de-la-Guarda Ruth
Centro Nacional de Salud Pública, Instituto Nacional de Salud, Lima, Peru.
Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Lima, Peru.
Microbiol Spectr. 2025 Jun 3;13(6):e0200424. doi: 10.1128/spectrum.02004-24. Epub 2025 May 14.
Despite widespread vaccination, pertussis (caused by ) persists in many countries, frequently causing outbreaks and severe cases in infants. The resurgence of pertussis may be due to genetic changes in the vaccine antigens of circulating strains. However, current typing methods, which depend on bacterial cultures, hinder our understanding of genotypes, especially in developing countries. This study aimed to analyze vaccine antigen-based genotypic variants (, , , and ) of in Peru from 2018 to 2019 via direct Sanger sequencing of nasopharyngeal swabs ( = 96). PCR-based sequencing was successful for the genes in 86% (83/96), in 100% (96/96), in 75% (72/96), and in 68% (65/96) of the samples. The variant was found in 100% (83/83), in 100% (96/96), in 97.3% (70/72), in 2.7% (2/72), and in 100% (65/65) of the samples. Sixty-three samples yielded a complete allelic profile, with genotype VI () predominating nationwide (96.8%), mainly in Lima (29.5%), Amazonas (13.1%), Callao (11.5%), and La Libertad (11.5%). Genotype VII () was less common (3.2%), found in Lima (50%) and Callao (50%). The predominance and expansion of genotype VI suggested the presence of biological traits linked to infection, possibly due to the allele, such as high respiratory colonization or increased pertussis toxin production, which could potentially increase disease transmission and severity. These findings will facilitate Peru's ability to monitor and control , improving public health responses and reducing the outbreak incidence and severity.
Despite widespread vaccination, pertussis (caused by ) still causes severe outbreaks in infants worldwide. Genetic changes in the vaccine antigens of strains may drive this resurgence. Current culture-based typing methods limit our understanding of these genotypes, particularly in developing countries. This study provides valuable insights into the genotypic variability of in Peru from 2018 to 2019, employing an isolation-free genotyping method allowing the direct Sanger sequencing of vaccine antigen genes from clinical samples. These findings can enhance public health decision-making by improving our understanding of the genetic changes that drive severe pertussis outbreaks, particularly in developing countries that use whole-cell vaccines. This knowledge enables rapid outbreak responses, improved vaccine strategies, and strengthened surveillance, prevention, and control measures.
尽管进行了广泛的疫苗接种，但百日咳（由 引起）在许多国家仍然存在，经常在婴儿中引发疫情和严重病例。百日咳的卷土重来可能是由于流行菌株疫苗抗原的基因变化。然而，目前依赖细菌培养的分型方法阻碍了我们对 基因型的了解，尤其是在发展中国家。本研究旨在通过对鼻咽拭子（ = 96）进行直接桑格测序，分析2018年至2019年秘鲁 基于疫苗抗原的基因变体（ 、 、 、和 ）。基于PCR的测序在86%（83/96）的样本中成功检测到 基因，在100%（96/96）的样本中成功检测到 基因，在75%（72/96）的样本中成功检测到 基因，在68%（65/96）的样本中成功检测到 基因。在100%（83/83）的样本中发现了 变体，在100%（96/96）的样本中发现了 变体，在97.3%（70/72）的样本中发现了 变体，在2.7%（2/72）的样本中发现了 变体，在100%（65/65）的样本中发现了 变体。63个样本产生了完整的等位基因图谱，基因型VI（ ）在全国占主导地位（96.8%），主要分布在利马（29.5%）、亚马逊（13.1%）、卡亚俄（11.5%）和自由省（11.5%）。基因型VII（ ）不太常见（3.2%），在利马（50%）和卡亚俄（50%）被发现。基因型VI的优势和扩展表明存在与感染相关的生物学特性，可能是由于 等位基因，如高呼吸道定植或百日咳毒素产量增加，这可能会增加疾病传播和严重程度。这些发现将有助于秘鲁监测和控制 ，改善公共卫生应对措施，降低疫情发生率和严重程度。
尽管进行了广泛的疫苗接种，但百日咳（由 引起）仍在全球范围内导致婴儿严重疫情。 菌株疫苗抗原的基因变化可能推动了这种卷土重来。目前基于培养的分型方法限制了我们对这些基因型的了解，特别是在发展中国家。本研究采用一种无需分离的基因分型方法，允许直接对临床样本中的疫苗抗原基因进行桑格测序，为2018年至2019年秘鲁 的基因变异性提供了有价值的见解。这些发现可以通过增进我们对导致严重百日咳疫情的基因变化的理解来加强公共卫生决策，特别是在使用全细胞疫苗的发展中国家。这些知识有助于快速应对疫情、改进疫苗策略以及加强监测、预防和控制措施。
