课件：流行性感冒禽流感课件.ppt

禽流感---人类感染 是否存在人 → 人传播： NO，但已发现其变异很快 是否有H5N1预防的疫苗： NO 为什么WHO建议疫区人员接种流感疫苗：防止病毒基因整合 药物对预防和治疗是否有效：YES，可选择离子通道M2阻滞剂和神经氨酸酶抑制剂。 为什么高致病性禽流感突然在东南亚爆发：不清楚，可能与候鸟迁徙和边境生鸡市场有关。 特别强调 （一）一般情况下，禽流感病毒感染人类的几率极小。 （二）目前尚无人与人之间传播的确切证据。 （三）国内尚无人禽流感病例。 （四）食用烹熟的家禽肉、蛋等不会感染禽流感。 （五）穿羽绒服、盖鸭绒被以及接触相关制品，不会传染禽流感。因为羽绒制品通常经过消毒、高温等多个物理、化学环节处理，病毒存活的可能性微乎其微。 THANK YOU SUCCESS * * 可编辑 * The influenza virus is transmitted through airborne exposure to virus expelled into the air by coughing, sneezing, or talking. Therefore, transmission of influenza is especially heavy in indoor gathering places such as schools or nursing homes. From 20% to 50% of a community population may be affected by any given outbreak, which usually peaks at about 3 weeks and recedes within another month.10 School-age children are a key source of dissemination for community epidemics and the major point of entry for the virus into the household.6 The first half of an epidemic is characterized by illness among school-age children, who present for medical treatment and who become absent from school. In the second part of the epidemic, infection spreads to preschoolers and adults, causing employee absenteeism and hospitalization of the elderly. Slide 7 Lecture Notes * Influenza is caused by viruses belonging to the Orthomyxoviridae family. The viruses are further classified according to the differing composition of their nuclear proteins into three types: type A, type B, and type C. Each type is associated with a different clinical and epidemiological profile. Influenza type A viruses cause potentially severe illness. Because they can change rapidly, type A viruses are responsible not only for epidemic but also pandemic infections that have swept the globe throughout this past century. This type of virus infects both humans and animals. Influenza type B viruses are more uniform than type A viruses. They infect only humans and usually produce less severe clinical illness than that associated with type A infections. However, ty