Lee Ji Hyen, Cho Hye-Kyung, Kim Kyung-Hyo, Lee Hyunju, Jo Dae Sun, Kim Han Wool
Center for Vaccine Evaluation and Study, Ewha Womans University College of Medicine, Seoul, Korea.
Department of Pediatrics, Ewha Womans University Seoul Hospital, Seoul, Korea.
Infect Chemother. 2025 Jun;57(2):218-229. doi: 10.3947/ic.2024.0127. Epub 2025 Apr 17.
Group B (GBS) is a major cause of invasive bacterial diseases, including sepsis, meningitis, and pneumonia, particularly in newborns and infants. Pregnant adults, those with pre-existing conditions, and older adults are particularly susceptible. Ongoing research is focused on developing various vaccines utilizing different antigens, including capsular polysaccharides and alpha-like proteins (Alps). Epidemiological data on these antigens in GBS is essential for predicting the effectiveness of these vaccines. However, no epidemiological studies on Alps genotype have been conducted in Korea. This study aimed to fill this gap by investigating the distribution and characteristics of the genotype in domestic clinical strains.
We analyzed 386 GBS strains isolated from various clinical specimens between April 2000 and November 2018. The serotype of each strain was initially verified using a slide latex agglutination reaction, then confirmed by polymerase chain reaction to determine the presence of the genes and associated with Alps. Strains were then classified as invasive or non-invasive based on the type of clinical specimen. The distribution of serotypes and genotype was analyzed across these classifications.
We analyzed 386 bacterial strains to assess their clinical characteristics, serotypes, and genotype distributions. Of these strains, 47.1% (182 strains) were invasive primarily isolated from blood samples (43.3%, 167 strains), whereas non-invasive strains were more frequently isolated from sites such as the vagina and urethra. Serotype III was the most prevalent across both invasive and non-invasive strains, comprising 28.2% (109 strains) of all isolates. Notably, 79.5% (307 strains) of all isolates were encompassed by the hexavalent vaccine (serotype Ia, Ib, II, III, and V) formulations. Furthermore, the genotype was the most common, detected in 39.4% (152 strains) of all isolates, with a higher prevalence in non-invasive samples (44.1%, 90 strains).
Although the distribution of genotypes differed between invasive and non-invasive strains, the proportion of bca and rib was substantial. Therefore, Alp protein vaccine containing Rib and Cα antigens is expected to provide protection against prevalent GBS strains in Korea. Additional epidemiological studies on GBS vaginal colonization in pregnant women and invasive neonatal strains are needed to support early neonatal sepsis prevention in these high-risk groups.
B族链球菌（GBS）是侵袭性细菌疾病的主要病因，包括败血症、脑膜炎和肺炎，尤其是在新生儿和婴儿中。孕妇、有基础疾病者以及老年人特别易感。正在进行的研究集中在开发利用不同抗原的各种疫苗，包括荚膜多糖和α样蛋白（Alps）。GBS中这些抗原的流行病学数据对于预测这些疫苗的有效性至关重要。然而，韩国尚未开展关于Alps基因型的流行病学研究。本研究旨在通过调查国内临床菌株中该基因型的分布和特征来填补这一空白。
我们分析了2000年4月至2018年11月期间从各种临床标本中分离出的386株GBS菌株。首先使用玻片乳胶凝集反应初步验证每株菌株的血清型，然后通过聚合酶链反应确认以确定与Alps相关的基因 和 的存在。然后根据临床标本类型将菌株分为侵袭性或非侵袭性。分析了这些分类中血清型和 基因型的分布。
我们分析了386株细菌菌株，以评估它们的临床特征、血清型和 基因型分布。在这些菌株中，47.1%（182株）为侵袭性菌株，主要从血液样本中分离得到（43.3%，167株），而非侵袭性菌株更频繁地从阴道和尿道等部位分离得到。血清型III在侵袭性和非侵袭性菌株中最为普遍，占所有分离株的28.2%（109株）。值得注意的是，所有分离株的79.5%（307株）被六价疫苗（血清型Ia、Ib、II、III和V）配方所涵盖。此外， 基因型最为常见，在所有分离株的39.4%（152株）中检测到，在非侵袭性样本中的患病率更高（44.1%，90株）。
虽然侵袭性和非侵袭性菌株之间 基因型的分布有所不同，但bca和rib的比例相当大。因此，含有Rib和Cα抗原的Alp蛋白疫苗有望为韩国流行的GBS菌株提供保护。需要对孕妇GBS阴道定植和侵袭性新生儿菌株进行更多的流行病学研究，以支持对这些高危人群早期预防新生儿败血症。
