Is smallpox contagious?

Under normal circumstances, smallpox is highly contagious. However, the disease has now been eradicated worldwide, with the virus preserved only in laboratories; thus, there is no need to worry about infection in daily life. The detailed analysis is as follows:

Prior to its eradication, smallpox was a highly virulent infectious disease primarily transmitted via respiratory droplets. Infection could also occur through direct contact with skin lesions of infected individuals or their contaminated clothing and belongings. The general population was universally susceptible. After infection, symptoms developed rapidly, initially presenting as high fever and headache, followed by macular rashes on the skin that progressed into papules, then evolving into vesicles and pustules, which could be fatal in severe cases.

The eradication of smallpox was achieved through widespread vaccination. The development of the cowpox vaccine provided effective immunity, and through global immunization programs and control measures, the disease has been completely eliminated worldwide. Since then, except for virus samples preserved in specialized laboratories, the smallpox virus no longer exists in nature.

Although smallpox has disappeared, it remains important to understand its historical prevention and control. In daily life, we should recognize the critical role of vaccination in preventing infectious diseases, cultivate good hygiene habits—such as frequent handwashing and avoiding contact with unknown sources of infection—and protect our health through scientific preventive practices, while passing on the successful experience of disease control.