Smallpox is a contagious viral infection which is caused by the variola virus. The virus presents as a severe illness with an abnormally high fever and body rash. The symptoms appears within approximately 12 days after exposure. The last reported case of smallpox was in 1977 and in 1980 the World Health Organization declared the virus to be wiped out. Because some people experienced adverse reactions and a few deaths occured from the smallpox vaccine, routine smallpox immunization ended in the United States in 1972.
Symptoms of smallpox includes a high fever, severe fatigue, a headache and backache. These symptoms take approximately 12 days to show and following 24-36 hours of the illness, a body rash appears. The rash appears on extremities and works inward until it spreads over the whole body. The red bumps from the rash then firm and fill with pus. After they scab over, and the scab sloughs off, a scar will remain.
Smallpox is not only spread through the respiratory system (sneezing, coughing or breathing) but is also passed through contact with the scabs or fluid leaking from the blisters. It is so contagious that the viral infection can be passed through the infected's clothing, bedding or other personal items. Smallpox is most contagious in the first week of the rash and becomes less contagious as scabs form over the rash.
The Center for Disease Control (CDC) still houses the smallpox virus. It is also known to be located at the Institute of Virus Preparations in Siberia, Russia. It is feared that terrorists could acquire the virus and spread smallpox through the air as the smallpox virus would survive and successfully infect people for 6 to 24 hours depending on the weather conditions.