The most important steps to stop a smallpox epidemic are isolation of smallpox cases, tracing of the contacts of these cases, and vaccination.
Patients showing signs of smallpox infection are capable of spreading the virus. Patients should be placed in medical isolation, so that they will not continue to spread the virus. In addition, people who have come into close contact with smallpox patients should be vaccinated immediately and closely watched for symptoms of smallpox. Vaccination and isolation are the key strategies for stopping a smallpox outbreak from spreading.