Siegrist C-A
Centre for Vaccinology and Neonatal Immunology, University of Geneva, CMU, 1 Michel Servet, 1211 Geneva 4, Switzerland.
J Comp Pathol. 2007 Jul;137 Suppl 1:S46-50. doi: 10.1016/j.jcpa.2007.04.012. Epub 2007 Jun 7.
A broad spectrum of adverse events is reported following human vaccination but such reactions are considered to be relatively rare. A variety of mechanisms has been proposed to account for such adverse events. These most commonly relate to the actual process of vaccination and range from the vagal reaction associated with anxiety about needle injection, to use of an inappropriate site of administration, or infection of the healthcare worker by accidental injection during needle-capping. Other adverse events directly associated with the vaccine include reversion to virulence of attenuated vaccine strains of organisms, or contamination of the vaccine product. Adverse events may involve immune-mediated phenomena triggered by exposure to the microbial or other components of vaccines. These include: classical IgE-mediated type I hypersensitivity reactions, and immune-complex type III hypersensitivity (Arthus) reactions. Such reactions may be localized or systemic in nature. A variety of autoimmune reactions has been suggested to be triggered by vaccination, but in general the evidence for such associations remains largely anecdotal. Finally, many reported adverse events are simply chance instances of infection or disease onset around the time of vaccination and are not causally associated with administration of vaccine.
接种疫苗后会出现各种各样的不良事件，但这类反应被认为相对罕见。人们提出了多种机制来解释此类不良事件。这些机制最常与实际接种过程有关，范围从与对注射针的焦虑相关的迷走神经反应，到使用不当的接种部位，或在针帽盖上时医护人员因意外注射而感染。与疫苗直接相关的其他不良事件包括减毒活疫苗菌株恢复毒力，或疫苗产品受到污染。不良事件可能涉及因接触疫苗的微生物或其他成分而引发的免疫介导现象。这些包括：经典的IgE介导的I型超敏反应和免疫复合物III型超敏（阿瑟斯）反应。此类反应在性质上可能是局部的或全身性的。有人提出接种疫苗会引发多种自身免疫反应，但总体而言，此类关联的证据在很大程度上仍只是传闻。最后，许多报告的不良事件仅仅是在接种疫苗前后碰巧发生感染或发病的情况，与疫苗接种并无因果关系。
