Disinfectants such as bleach can be used for cleaning contaminated surfaces. If used in biowarfare, smallpox virus could be dispersed in the air and potential victims in the area of the release would breathe in the virus, or infected persons could be sent into a crowded area to attempt to spread the disease to others.

Viewpoint: No. The American Revolution was a conservative movement intended to preserve the existing social, political, and economic order. As divided as historians are over the causes of the American Revolution (1775-1783), they are in even greater disagreement over its consequences.

Edward Jenner, the English physician who first developed the smallpox vaccine in 1796, believed that vaccination caused a fundamental change in personal constitution and would lead to lifelong immunity to smallpox. Unfortunately, this proved to be incorrect. It is now clear that immunity wanes over time.

Cowpox, also called vaccinia, mildly eruptive disease of cows that when transmitted to otherwise healthy humans produces immunity to smallpox. The cowpox virus is closely related to variola, the causative virus of smallpox.

The rash looks like red bumps that gradually fill with a milky fluid. The fluid-filled bumps are all in the same stage at the same time, compared to chickenpox, where the skin blisters are in different stages of appearance with a mix of blisters, bumps, and crusted lesions at a given time.

The highest smallpox infection rates were in persons 0–19 years of age, but the highest death rates were in those >45 years of age. Because of the low level of residual vaccine immunity, immunosuppression was more influential than vaccination on death and infection rates in our model.

The smallpox vaccine was given by a special technique that caused a blister which formed a scab and when the scab fell off, it left a scar (usually in the deltoid area of the upper arm). Bacille Calmette-Guérin (BCG) Vaccine: The BCG vaccine is not currently recommended for routine use in any Canadian population.