Dryvax - produced by scraping virus off the skin of infected calves is now replaced by a new-generation smallpox vaccine, ACAM2000. The new live, vaccinia virus smallpox vaccine was licensed for use in the United States by the Food and Drug Administration in August 2007. It is derived from plaque purification cloning from Dryvax.
Dryvax, which was created in the late 1800s by Wyeth, is considered unsafe now as it was linked to a series of heart attacks and a painful heart inflammation in some patients. The CDC issued instructions to destroy the vaccine carefully and effectively.
The United States ended the routine childhood vaccination against the disease by the early 1970s after the world health authorities declared the disease was eradicated from nature in 1980.
Smallpox is a serious, contagious, and sometimes fatal infectious disease. There is no specific treatment for smallpox disease, and the only prevention is vaccination. It killed nearly a third of the people it infected. Victims suffered from high fever and body aches, then spots and blisters that would leave survivors with pitted scars.
Unlike Dryvax, ACAM2000 is created in laboratories and not on a farm, so it gets expired after 18 months of manufacturing. There's also much less possibility of bacterial contamination in the production process.
