水痘是由水痘-带状疱疹病毒(varicella-zoster virus,VZV)引起的发热出疹性疾病,儿童常见,以发热伴周身性红色斑疹、丘疹、疱疹为主要临床特征~([1])。水痘一般预后较好,但重症水痘或并发重型脑炎、肺炎者可致死亡。水痘传染性很强,易感儿童接触后80%~90%发病,学校、幼儿园等儿童聚集单位易发生暴发,严重影响了儿童的身心健康和学习生活,并造成经济负担~([2])。为了解天津市水痘暴发疫情的流行 Chickenpox is a febrile and rash disease caused by varicella-zoster virus (VZV). Children are common, with fever and peripheral erythema, papules and herpes as the main clinical features ~ ([1]) . The general prognosis of chickenpox is good, but severe chickenpox or complicated with severe encephalitis, pneumonia can cause death. Chickenpox is very contagious and affects 80% -90% of the children exposed to the disease. It is easy for an outbreak of children’s aggregation in schools, kindergartens and other places, seriously affecting the children’s physical and psychological health and learning and living, and causing financial burdens ([2]) . To understand the outbreak of varicella in Tianjin epidemic