The reaction to the vaccine lasts a lifetime. Some are mild, many are not. I don't take anything for malaria either, but I have a better chance of getting it than contracting small pox. The SF troops that came back to Ft Bragg and killed their wives were all give a "safe" vaccine. The Pentagon will deny that it had anything to do with the killings just like they claim there's no "Gulf War Syndrome" that they can find. Only Gulf War vets who were in the Middle East, and now their families, have it, but it doesn't exist. You try it, I'll wait.