Chen Xiaoli, Zuo Weilun, Xu Qunshan, Chen Ling, Wang Ye, Liu Jumei, Fu Xiaochun, Zhu Min, Yang Xiaoqing, Ye Huiming
Department of Laboratory Medicine, Fujian Key Clinical Specialty of Laboratory Medicine, Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, Fujian Province, China.
Department Pediatrics, Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, Fujian Province, China.
Vaccine. 2025 Apr 19;53:127081. doi: 10.1016/j.vaccine.2025.127081. Epub 2025 Apr 2.
In 2024, the reported incidence of pertussis in China has increased sharply. As a vulnerable group, neonates continue to be at highest risk of severe outcomes from pertussis infection. However, there have been no serological assessment of population immunity since the 2024 pertussis outbreak in China. This study aimed to ascertain the PT-antibody status of pregnant women and their newborns during the epidemic period and offer insights to maternal immunization in China.
From April to June 2024, 227 newborn-mother pairs in Xiamen City were recruited to test serum anti-PT IgG levels by ELISA. The geometric mean, undetectable rate (< 5 IU/mL), seropositivity rate (≥ 40 IU/mL), recent infection rate (≥ 100 IU/mL), and newborn-to-maternal ratio of anti-PT IgG were calculated. Statistical analysis was made based on maternal age, gravidity, parity, delivery mode, gestational age and newborn sex.
The anti-PT IgG levels were positively correlated (R = 0.761) between pregnant women and their newborns. We found that 97.8 % of participants were seronegative, and 75.3 % of pregnant woman and 64.3 % of newborn had anti-PT IgG levels below 5 IU/mL. The seropositive prevalence of them were both only 2.2 % (95 % CI 0.9-5.1). The newborn-to-maternal ratio was stable in the range of 1.1 to 1.3 across all groups. There was no significant difference in the anti-PT IgG level of all participants across maternal and neonatal demographic characteristics. There was also no significant difference in the prevalence of seropositivity across demographic characteristics, except for delivery mode among newborns.
Almost all of the pregnant women and their newborns in this study had anti-PT IgG levels low enough to suggest susceptibility to pertussis infection, especially during an epidemic period. Infants are unprotected until the onset of primary immunization series, which would support the rationale for maternal immunization.
2024年，中国报告的百日咳发病率急剧上升。新生儿作为弱势群体，仍然是百日咳感染导致严重后果的最高风险人群。然而，自2024年中国百日咳疫情爆发以来，尚未对人群免疫力进行血清学评估。本研究旨在确定疫情期间孕妇及其新生儿的百日咳毒素（PT）抗体状态，并为中国的孕产妇免疫提供见解。
2024年4月至6月，招募了厦门市的227对新生儿-母亲对，通过酶联免疫吸附测定法（ELISA）检测血清抗PT IgG水平。计算几何平均数、不可检测率（<5 IU/mL）、血清阳性率（≥40 IU/mL）、近期感染率（≥100 IU/mL）以及新生儿与母亲抗PT IgG的比值。根据母亲年龄、妊娠次数、产次、分娩方式、孕周和新生儿性别进行统计分析。
孕妇及其新生儿的抗PT IgG水平呈正相关（R = 0.761）。我们发现97.8%的参与者血清学阴性，75.3%的孕妇和64.3%的新生儿抗PT IgG水平低于5 IU/mL。他们的血清阳性患病率均仅为2.2%（95%置信区间0.9 - 5.1）。所有组的新生儿与母亲的比值在1.1至1.3范围内稳定。所有参与者的抗PT IgG水平在母亲和新生儿人口统计学特征方面无显著差异。除新生儿的分娩方式外，血清阳性患病率在人口统计学特征方面也无显著差异。
本研究中几乎所有孕妇及其新生儿的抗PT IgG水平都低到足以表明对百日咳感染易感，尤其是在疫情期间。婴儿在初次免疫系列开始之前没有保护，这将支持孕产妇免疫的基本原理。
