病毒是一类比细菌还小几十倍的微生物,只能在细胞和寄主机体内增殖,需要用电子显微镜才能够看到。病毒入侵机体后,先在入侵部位的易感细胞中增殖,破坏感染细胞的合成与结构功能,导致病变坏死。并向临近的细胞和淋巴细胞扩散,形成局部的感染灶,进一步经血液侵入皮肤、肝脏、肾脏和脑等组织,导致器官病 Viruses are a class of microbes that are a few dozen times smaller than bacteria and proliferate only in cells and host organisms and need to be seen with an electron microscope. After the virus invades the body, it first proliferates in susceptible cells at the invasion site, destroying the synthesis and structural functions of infected cells, resulting in necrosis of the lesion. And to the adjacent cells and lymphocyte proliferation, the formation of local infection foci, and further by the blood invades the skin, liver, kidney and brain tissue, resulting in organ disease