How is the smallpox vaccine administered?

The smallpox vaccine is administered using a bifurcated needle. This method is specifically designed for this type of vaccine, distinguishing it from typical injections. The bifurcated needle has a forked end that allows for the vaccine to be introduced into the skin effectively. When the needle is dipped into the vaccine, it is then pricked into the skin's surface multiple times, which is essential for the vaccine's effectiveness in triggering an immune response against the smallpox virus.

This method helps to ensure that a sufficient amount of the vaccine is delivered to the body without the need for deeper injection techniques, such as intramuscular or subcutaneous injections. The unique delivery method of the bifurcated needle is integral to the smallpox vaccine's historical success in eradicating the disease.