The smallpox vaccine was used until the early 1970s to wipe out smallpox worldwide. Much like other vaccines, the smallpox vaccine protects against infection by helping your body develop immunity to the smallpox virus. The smallpox vaccine is made from a live virus that’s very similar to the smallpox virus. The vaccine doesn’t cause smallpox, but it can cause life-threatening problems in some people (especially in people who have a weakened immune system).
For most people, whether they are vaccinated against smallpox depends on whether there has been an outbreak of the disease. In most cases, the vaccine causes mild side effects, such as soreness around the vaccination site, fever, and body aches. A very small percentage of people will suffer serious side effects and may even die. Thus the vaccine is only necessary when there has been an outbreak of smallpox, or for a group of people who have been exposed to the virus. The following groups of people are more likely to have severe reactions and should only be vaccinated if actually exposed to smallpox:
Probably not. Studies show that the vaccine is most effective for 3 to 5 years after vaccination.
Written by familydoctor.org editorial staff