Smallpox

Smallpox is a serious, contagious, and sometimes fatal infectious disease. There is no specific treatment for smallpox disease, and the only prevention is vaccination. The name smallpox is derived from the Latin word for "spotted" and refers to the raised bumps that appear on the face and body of an infected person.

There are two clinical forms of smallpox. Variola major is the severe and most common form of smallpox, with a more extensive rash and higher fever. There are four types of variola major smallpox: ordinary (the most frequent type, accounting for 90% or more of cases); modified (mild and occurring in previously vaccinated persons); flat; and hemorrhagic (both rare and very severe). Historically, variola major has an overall fatality rate of about 30%; however, flat and hemorrhagic smallpox usually are fatal. Variola minor is a less common presentation of smallpox, and a much less severe disease, with death rates historically of 1% or less.

Smallpox outbreaks have occurred from time to time for thousands of years, but the disease is now eradicated after a successful worldwide vaccination program. The last case of smallpox in the United States was in 1949. The last naturally occurring case in the world was in Somalia in 1977. After the disease was eliminated from the world, routine vaccination against smallpox among the general public was stopped because it was no longer necessary for prevention.

Smallpox has an incubation time of 7 to 16 days following exposure. Smallpox begins with something that's a lot like chicken pox with small blisters forming on the skin, especially on the face, chest and hands. But then as days go by, the blisters grow larger and a high fever develops that comes and goes. Victims eventually go into shock and may also suffer from secondary infections in blisters. The disease is highly contagious and most Americans, even those once vaccinated for it, would probably contract it as resistance from vaccines lasts for only a decade or so.

Transmission can be through direct contact, aerosol, ingestion, or parenteral administration. Because person-to-person transmission will be highly likely following an attack involving Smallpox, great care must be devoted to proper sanitation and particularly to isolation of those who have not contracted it from those who are ill.