Chickenpox and smallpox are not the same virus. Although smallpox and chickenpox are both highly contagious viral skin diseases, the diseases themselves are different because of the different viruses that infect them. Smallpox is a more serious infectious disease induced by smallpox virus infection, which has now been completely eradicated because of the widespread use of vaccines in China. After vaccination, the human body will obtain permanent immunity, and the chance of contracting smallpox is almost zero. Chickenpox, on the other hand, is an acute contagious skin disease, caused by varicella~herpes zoster virus infection, which usually causes the patient to develop fever, rash and other symptoms. Moreover, the duration of chickenpox is usually about 1~2 weeks, and even after vaccination, there is no life-long lasting immunity. To summarize, chickenpox and smallpox are not the same virus and are completely different. If a patient suffers from one of the above diseases, it is important to follow medical advice under the supervision of a doctor.