Chung Hyemin, Cho Sung-Kwan, Joo Jiyeon, Kim Sun-Kyung, Kim Eun Ok, Kim Min Jae, Chong Yong Pil, Choi Sang-Ho, Lee Sang-Oh, Kim Yang Soo, Jung Jiwon, Kim Sung-Han
Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Division of Infectious Diseases, Department of Internal Medicine, Chung-Ang University Gwangmyeong Hospital, Gwangmyeong, Korea.
Infect Chemother. 2023 Sep;55(3):388-393. doi: 10.3947/ic.2023.0049. Epub 2023 Aug 4.
Sporadic measles outbreaks have continued to occur in Korea, mainly in adults in their 20s and 30s, most notably in 2014 and 2019. We here evaluated the possible causes of a low seroprevalance of measles by testing young healthcare workers (HCWs).
This study was conducted in a 2,743-bed tertiary-care hospital in Seoul between 2020 and 2021. We performed a measles antibody test (chemiluminescence immunoassay), measured the IgM/IgG index ratio, and conducted an avidity test at 1-month after Measles-Mumps-Rubella (MMR) vaccination in HCWs who had been seronegative for measles. Measles vaccination histories were obtained from the national vaccine registry.
Of the 3,173 HCWs newly employed in our hospital during the study period, 54 with a negative measles IgG at commencement were enrolled. Thirty six (67%) of these subjects were female, and the median age was 25 years (interquartile range [IQR]: 24 - 27). Fourty nine (91%) showed seroconversion at 1 month after the first vaccination. Of these individuals, 38 received both measles IgM and IgG test, and all had an IgM/IgG index <1. Of the 49 seroconverters, all HCWs showed a high avidity index. According to the national immunization registry, 45 (83%) received at least 2 doses of an MMR vaccination.
Secondary vaccine failure may underlie vaccine failure in young Korean adults. HCWs born after 1985 with a negative measles antibody may need only a single dose booster vaccination rather than a 2-dose vaccination regimen.
韩国仍不时出现散发性麻疹疫情，主要发生在二三十岁的成年人中，最显著的是在2014年和2019年。我们通过检测年轻医护人员来评估麻疹血清阳性率低的可能原因。
本研究于2020年至2021年在首尔一家拥有2743张床位的三级医院进行。我们对麻疹血清学阴性的医护人员进行了麻疹抗体检测（化学发光免疫分析），测量了IgM/IgG指数比，并在接种麻疹-腮腺炎-风疹（MMR）疫苗1个月后进行了亲和力检测。麻疹疫苗接种史来自国家疫苗登记处。
在研究期间新入职我院的3173名医护人员中，54名入职时麻疹IgG阴性的人员被纳入研究。其中36名（67%）为女性，中位年龄为25岁（四分位间距[IQR]：24 - 27）。49名（91%）在首次接种疫苗1个月后出现血清转化。在这些个体中，38名接受了麻疹IgM和IgG检测，所有人员的IgM/IgG指数均<1。在49名血清转化者中，所有医护人员的亲和力指数均较高。根据国家免疫登记处的数据，45名（83%）至少接种了2剂MMR疫苗。
继发性疫苗失败可能是韩国年轻成年人疫苗接种失败的原因。1985年后出生且麻疹抗体阴性的医护人员可能只需接种一剂加强疫苗，而非两剂接种方案。
