Background - Smallpox Disease

Smallpox was a serious infectious disease caused by a virus known as the variola virus. The name "smallpox" comes from the Latin word for "spotted", which refers to the raised bumps that appear on the face and body of an infected person. The symptoms of smallpox begin with high fever, chills, head and body aches, and sometimes vomiting. A rash then emerges on the tongue and mouth and spreads to the skin, forming on the arms and legs and then to the hands and feet. The rash progresses to raised bumps and pus-filled blisters that crust, scab, and fall off after about three weeks, leaving a pitted scar.

Smallpox is ordinarily transmitted through direct and fairly prolonged face-to-face contact between people. The virus is spread through particles that are released from coughing or sneezing after a person has developed scabs in their mouth and throat. Smallpox case scabs remain contagious/infectious until the scabs fall off, so skin-to-skin contact and contact with clothing, bedding and other personal items that may harbor skin/scabs can transmit the infection.

The following references aid in recognizing disease characteristics and hazards associated with smallpox.

• Smallpox. Centers for Disease Control and Prevention (CDC). Contains extensive smallpox information, including fact sheets; overviews; FAQs; diagnosis and evaluation; infection control, laboratory testing; surveillance and investigation; selected publications; and education and training materials.
• Public Health Image Library (PHIL). Centers for Disease Control and Prevention (CDC). Offers several images related to smallpox that include descriptions.
• Smallpox. World Health Organization (WHO) Health Topics. Provides information on smallpox, including a fact sheet, disease outbreak information, publications, and related links.