Nakayama Tetsuo, Onoda Kazumasa
Laboratory of Viral Infection I, Kitasato Institutes for Life Sciences, Kitasato University, Shirokane 5-9-1, Minato-ku, Tokyo 108-8641, Japan.
Vaccine. 2007 Jan 5;25(3):570-6. doi: 10.1016/j.vaccine.2006.05.130. Epub 2006 Aug 4.
General physicians, pediatricians and parents realize that serious adverse events occur with an extremely rare incidence, but have no information on the incidences of vaccine-associated adverse events. A proper understanding of vaccine adverse events would be helpful in promoting an immunization strategy. Causal association can rarely be determined in adverse events through laboratory examinations. We examined the cases reported in the post-marketing surveillance of the Kitasato Institute, categorizing them into two groups: allergic reactions and severe systemic illnesses. Anaphylactic patients with gelatin allergy after immunization with live measles, rubella and mumps monovalent vaccines have been reported since 1993, but the number of reported cases with anaphylaxis dramatically decreased after 1999 when gelatin was removed from all brands of DPT. The incidence of anaphylactic reaction was estimated to be 0.63 per million for Japanese encephalitis virus (JEV) vaccine, 0.95 for DPT and 0.68 for Influenza vaccine, but the causative component has not yet been specified. Among 67.2 million immunization practices, 6 cases with encephalitis or encephalopathy, 7 with acute disseminated encephalomyelitis (ADEM), 10 with Guillain-Barré syndrome and 12 with idiopathic thrombocytopenic purpura (ITP) were reported. The wild-type measles virus genome was detected in a patient with encephalitis and in two of four bone marrow aspirates obtained from ITP after measles vaccination. Enterovirus infection was identified in two patients after mumps vaccination (one each with encephalitis and ADEM), one patient with encephalitis after immunization with JEV vaccine, and one with aseptic meningitis after immunization with influenza vaccine. The total estimated incidence of serious neurological illness after vaccination was 0.1-0.2 per million immunization practices. We found that enterovirus or wild-type measles virus infection was coincidentally associated with vaccination in several cases suspected of being vaccine adverse events.
普通内科医生、儿科医生和家长都意识到严重不良事件的发生率极低，但他们并不了解疫苗相关不良事件的发生率。正确认识疫苗不良事件将有助于推动免疫策略。通过实验室检查很少能确定不良事件中的因果关系。我们研究了北里研究所上市后监测中报告的病例，将其分为两组：过敏反应和严重全身性疾病。自1993年以来，已有接种麻疹、风疹和腮腺炎单价活疫苗后发生明胶过敏的过敏反应患者报告，但1999年所有品牌的白百破疫苗都不再使用明胶后，报告的过敏反应病例数量大幅下降。据估计，日本脑炎病毒（JEV）疫苗的过敏反应发生率为每百万剂0.63例，白百破疫苗为0.95例，流感疫苗为0.68例，但致病成分尚未明确。在6720万次免疫接种中，报告了6例脑炎或脑病、7例急性播散性脑脊髓炎（ADEM）、10例吉兰-巴雷综合征和12例特发性血小板减少性紫癜（ITP）。在1例脑炎患者以及4例麻疹疫苗接种后ITP患者的骨髓抽吸物中的2例中检测到野生型麻疹病毒基因组。在2例腮腺炎疫苗接种后的患者中发现肠道病毒感染（1例脑炎，1例ADEM），1例JEV疫苗接种后脑炎患者，1例流感疫苗接种后无菌性脑膜炎患者。接种疫苗后严重神经系统疾病的总估计发生率为每百万次免疫接种0.1 - 0.2例。我们发现，在几例疑似疫苗不良事件的病例中，肠道病毒或野生型麻疹病毒感染与疫苗接种同时发生。
