11.   Injuries caused by vaccines are extremely rare, and controversial.

12.   In the suit, Bonsignore lays out the circumstantial case that has led some parents and doctors to believe that the vaccines can cause autism.

13.   Medical experts say the new vaccine causes fewer immediate side effects such as redness and swelling.

14.   Rosenstein of the CDC says the question parents most often ask her is whether the vaccine can cause meningococcal infections.

15.   The American vaccine can cause redness and itching at the site of the injection and sometimes flulike illnesses.

16.   The CDC says vaccines cause so few ill effects that the risks cannot be reliably measured.

17.   The class-action suits also ask that the manufacturer be directed to set up a fund to determine whether the vaccine is causing serious illnesses.

18.   The study, financed by the Centers for Disease Control, found that the vaccines could cause fevers, and seizures in rare cases.

19.   The TB vaccine causes the immune system to produce antibodies and other proteins that combat TB.

20.   The standard smallpox vaccine can cause a variety of severe, even fatal, reactions.