Nomura Shuhei, Eguchi Akifumi, Yoneoka Daisuke, Murakami Michio, Ghaznavi Cyrus, Gilmour Stuart, Kaneko Satoshi, Kawashima Takayuki, Kunishima Hiroyuki, Naito Wataru, Sakamoto Haruka, Maruyama-Sakurai Keiko, Takahashi Arata, Takayama Yoshihiro, Tanoue Yuta, Yamamoto Yoshiko, Yasutaka Tetsuo, Miyata Hiroaki
Department of Health Policy and Management, School of Medicine, Keio University, Tokyo, Japan.
Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Lancet Reg Health West Pac. 2022 Oct;27:100541. doi: 10.1016/j.lanwpc.2022.100541. Epub 2022 Jul 21.
Vaccine hesitancy is a global public health threat. We present unique data that characterises those who experienced reversals of COVID-19 vaccination hesitancy in Japan.
We administered a questionnaire on vaccination intention among 30053 Japanese adults aged 20 years or older before the COVID-19 vaccination was available to the general population (first survey) and conducted a follow-up survey on vaccination status one year later in February 2022 (second survey). Those who responded in the first survey that they did not intend to be vaccinated or were unsure and then responded in the second survey that they were vaccinated or intend to be vaccinated were asked about the reasons for their change of heart. Based on previous literature and expert opinion, 31 reasons for changing vaccination intention were compiled and respondents were asked to choose which among them applied to themselves, with multiple responses possible. Based on the results of those responses, each individual was then clustered using the Uniform Manifold Approximation and Projection (UMAP) dimensionality reduction technique and Ordering Points To Identify the Clustering Structure (OPTICS) algorithm. We then identified unique characteristics among each of the sub-populations (clusters).
In the second survey we received 19195 responses (response rate 63.9%), of which 8077 responded 'no' or 'not sure' in the first survey regarding their intention to be vaccinated. Of these, 5861 responded having received or intending to receive the vaccine (72.6%). We detected six and five sub-populations (clusters) among the 'no' group and 'not sure' group, respectively. The clusters were characterized by perceived benefits of vaccination, including the COVID-19 vaccine, awareness of the COVID-19 vaccination status of those close to them, recognition of the social significance of COVID-19 vaccination for the spread of infection, and dispelled concerns about short-term adverse reactions and the safety of the COVID-19 vaccine. Work and personal relationship reasons were also found to be a unique overarching reason for vaccination changes of heart only among those who did not intend to vaccinate.
Those who changed their intention to accept COVID-19 vaccination as well as their unique characteristics as detailed in this study will be important entry points when discussing how to promote vaccination to those who are hesitant to vaccinate in the future.
The present work was supported in part by a grant from the Kanagawa Prefectural Government of Japan and by AIST government subsidies.
疫苗犹豫是一种全球公共卫生威胁。我们提供了独特的数据，以描述在日本经历新冠疫苗接种犹豫态度转变的人群特征。
在新冠疫苗面向普通人群可用之前（首次调查），我们对30053名20岁及以上的日本成年人进行了关于接种意愿的问卷调查，并于一年后的2022年2月进行了关于接种状态的后续调查（第二次调查）。那些在首次调查中表示不打算接种或不确定，而在第二次调查中表示已接种或打算接种的人被问及改变主意的原因。根据以往文献和专家意见，整理出31个改变接种意愿的原因，并要求受访者选择适用于自己的原因，可进行多项选择。根据这些回答的结果，然后使用均匀流形逼近与投影（UMAP）降维技术和排序点识别聚类结构（OPTICS）算法对每个人进行聚类。然后我们确定了每个亚人群（聚类）的独特特征。
在第二次调查中，我们收到了19195份回复（回复率63.9%），其中8077人在首次调查中对其接种意愿回答“否”或“不确定”。其中，5861人回复已接种或打算接种疫苗（72.6%）。我们在“否”组和“不确定”组中分别检测到6个和5个亚人群（聚类）。这些聚类的特征包括对接种疫苗（包括新冠疫苗）的感知益处、对身边人新冠疫苗接种状况的了解、认识到新冠疫苗接种对感染传播的社会意义，以及消除对短期不良反应和新冠疫苗安全性的担忧。工作和个人关系原因也被发现是仅在那些不打算接种疫苗的人群中改变接种意愿的一个独特的总体原因。
那些改变了接受新冠疫苗接种意愿的人以及本研究中详细描述的他们的独特特征，将是未来讨论如何向犹豫接种疫苗的人推广疫苗接种时的重要切入点。
本研究部分得到了日本神奈川县政府的资助以及日本产业技术综合研究所的政府补贴。
