研究の目的 : 多変量解析とGISを用いて、乳幼児を対象とする日本の予防接種率の地域差の実態を把握し、その要因を検討する。研究の背景 : 公衆衛生上の課題である予防接種率の地域差の特定と改善を目的として、多様な地域スケールからその要因を分析する研究が行われている。しかしながら、日本における既往研究では個人を対象とした研究が多く、接種率の地域差の検討や関連要因を用いた生態学的研究もほとんど行われてこなかった。研究手法 : 日本の1737の市区町村における7種類19回の予防接種を対象として、重回帰分析と市区町村―都道府県間の階層を用いたマルチレベル分析を行った。被説明変数には推計した2013年から2018年までの予防接種率を、説明変数には9つの個人要因と4つの環境要因を用いた。これらの変数の作成には国勢調査などの政府統計を用いた。予防接種率の分布図と予測モデルの残差プロットを用いて、地理的な関連要因を探索した。結果 : 一人当たり課税所得と乳幼児健診受診率は市区町村レベルで、世帯の児童数は都道府県レベルで全般的に有意な関連を示した。その他の変数は予防接種の種類や接種時期(回数)によって関連の有無が異なった。接種率は西日本で低く、大都市圏で高い傾向がみられた。残差は内陸部と接種率の偏差が大きい地域に多く見られた。考察 : 市区町村の所得格差と都道府県の世帯あたり児童数の差が、地域の接種率の格差に関連すると示唆された。また、人口減少と高齢化が進む小規模地域には接種率に関連する固有の因子が存在する可能性がある。結論 : 接種率の向上には、その地域の社会経済的状況や人口構造、地域の文脈、予防接種の種類、それらの要因の影響するスケールを踏まえた施策が求められる。 / Objective: Examining geographical variation and the factors of infant immunization coverage in Japan. Background: Incomplete vaccination coverage is one of the largest public health threats. Many interdisciplinary studies have investigated factors that might increase immunization rates or cause Vaccine Hesitancy. However, most studies in Japan have focused on individuals and few studies have considered regional disparities of vaccination coverage. Methods: We conducted a multiple regression analysis and a multilevel analysis (municipality-prefecture hierarchy) for 19 vaccinations in 1737 municipalities in Japan, during 2013-2018. The dependent variable was the estimated vaccination rate, and nine individual factors and four environmental factors were used as explanatory variables. Data were collected from publicly available sources. We used distribution maps of vaccination rates and residuals of the predictive models to explore geographical factors. Results: In general, per capita taxable income and infant health checkup rate showed generally significant positive associations at the municipal level, and the number of children in the household negative association at the prefectural level. Other factors showed various associations depending on the type and the timing of vaccines. Vaccination rates were likely to be lower in western Japan and higher in metropolitan areas. Residuals were found mostly in inland areas and areas with large deviations in vaccination rates. Discussion: These results suggested that vaccination rates were associated with regional differences in municipal income inequality and in the number of children per household in prefectures. Smaller villages with declining and aging populations might have unique factors. Conclusions: To increase vaccination coverage among infants, it requires to consider the effect size at various spatial scales, in addition to compositional and contextual effects as the socioeconomic status, demographic structure, the local contexts, and the type of vaccination. / 京都大学 / 修士 / 修士(文学) / Kyoto University / TFtmp

The rapid development and disitribution of COVID-19 vaccines have sparked diverse public reactions globally, often reflected through social media platförms like Twitter. This study aims to analyze the sentiment andd public discourse surrounding COVID-19 vaccines on Twitter, utilizing advanced text classification techniques to navigare the vast, unstructured nature of sicial media dfata. By implementing sentiment analysis, the research categoizes tweets into positive, negative, and neutral sentiments to gauge public opinion more effectively. In-depth analysis thorugh topic modelingtecniques helped identify seven key topicvs influencing public sentiment including aspects related to efficiacy, logisticl challenges, safety concens, and personal experiences, each varying in prominence depending on the country, as well as the specific timeline of vaccine deployment. Additionally, this study explorers geographical variations in sentiment, notig significant differences in public opinion across different countries. These variations could be tied to local cultural, social, and political contexts. Reults from this study show a polarized response towards vaccination, with significant discourse clusers showing either strong supprt for or resistance against the COVID-19 vaccination efforts. This polarization is further pronounced by the logistical challenges and trust issues related to vaccine science, particularly emphasized in tweets from couintries with lower vaccine acceptance rates. This sentiment analysis on Twitter offers valuable insights into the public's perception and acceptancce of COVID-19 vaccines, providing a useful tool for policymakers and public health officials to understand and address publiv concerns effectively. By identifying and understanding the key factors influencing vaccine sentiment, tageted communication strategies can be developed to enhance publiv engagement and vaccine uptake.

Helper T cells direct the immunological response to foreign pathogens and cancer. To become activated, helper T cells must recognize unique peptides presented on major histocompatibility complex II (pMHCII) by antigen presenting cells (APCs) with their T cell receptor (TCR). While much is known about helper T cell activation signaling cascades and the subsequent roles of helper T cell subsets, the initiation of helper T cell activation by the TCR and other co-receptors is less well understood. Specifically, the affinity of the TCR for its pMHCII can change helper T cell subset fate, proliferation, and alter the risk for activation induced cell death. High affinity TCRs are attractive targets for immunotherapies, but little is known about how helper T cells respond to high affinity TCRs. Here we describe high affinity TCR activation thresholds for both full length TCRs and chimeric antigen receptor TCRs both with and without the presence of the coreceptor CD4 and propose a mechanism whereby CD4 inhibits T cell activation via Lck sequestration and a CD4-independent method. Dysregulated helper T cells play critical roles in the development and perpetuation of systemic lupus erythematosus (SLE), a systemic autoimmune disease that causes widespread inflammation and organ damage throughout the body. Chronic inflammation in SLE affects the immune response to viruses and the risk of developing cancer. However, in SLE patients, it is unclear if viruses initiate the development of cancer directly or if the effects are non-interacting and concomitant. Here we describe the interactions between SLE, viruses, and cancer risk revealing that viruses and SLE do interact to increase the both the overall cancer risk and the risk for hematological malignancies. Due to vaccine efficacy, vaccine preventable diseases (VPDs) are no longer commonly experienced or understood by the public. Vaccines are a victim of their own success and according to the World Health Organization (WHO), vaccine hesitancy (VH) is one of the top threats to global health. VH is the refusal to accept vaccinations and the reasons for VH vary across time, place, and vaccine. Refuting VH is difficult as directly confronting false assumptions can cause individuals to become more entrenched in their position resulting in confirmation bias. Adults with VH attitudes are often motivated by concerns over personal liberty, harm, independence, and body purity. Here we describe the results of a VPD interview- and education-based intervention geared towards promoting positive vaccine attitudes for young adults and demonstrate that education focused on VPDs is more effective than vaccine safety.