Aim: How does your body become immune (resistant) to disease?

Bioterrorism Today there is mounting concern about the threat of a bioterrorist attack using smallpox -- so much concern that in October 2001 the American government decided to order enough vaccines to protect every U.S. citizen. Smallpox has a fearsome reputation, having killed more people in history than any other infectious disease. Fatal hemorrhagic smallpox in a twelve-year-old girl, 1970s, Bangladesh. A genetically - engineered strain of smallpox might produce unusual symptoms such as these. Here, the eyes are filled with blood, and blood blisters form in the mouth and inside the body. How can we protect ourselves? Show 12 monkeys

What is a vaccine? Antigen Weakened Pathogen Antibody A vaccine is a weaken or dead form of a pathogen,but it still has the antigens present.

Why is it important that the antigens are still present? If the antigens are present, it will cause the body to trigger an immune response! The body will make specific antibodies and WBC to fight off the antigen. Some of these WBC will remain in the body for future attacks!

Will a vaccine cause someone to get sick? Someone may experience mild symptoms but they will not get a full blown case of the disease!

How was the first Vaccine developed? English physician Edward Jenner developed an inoculation against smallpox in 1796. Armed with the knowledge that milkmaids who had been exposed to cowpox, a relatively mild affliction, didn't come down with smallpox, Jenner intentionally infected an eight-year-old boy with cowpox. Two months later he infected the boy again, this time with smallpox. As Jenner expected, the child didn't come down with the disease -- he was immune.

How do scientists make vaccines? http://www.pbs.org/wgbh/nova/bioterror/vaccines.html Obtain pathogen Treat pathogen to kill or weaken it. Inject altered pathogen (vaccine) into organism. Body responds to antigens by making antibodies & having WBCs attack invader. 5) Some WBCs specific for this pathogen remain in the body to protect the organism from future attacks.

What happens when you get invaded by the real pathogen? Memory Cells Some white blood cells specific for this pathogen (called Memory Cells) are already present and will multiply quickly and destroy the invader before it has the chance to cause the disease.

What is immunity? The ability of a person who once had a disease to be protected from getting the same disease again.

Vaccines

Types of Immunity: Active vs. Passive Passive Immunity You get antibodies from a different organism, you don’t make your own antibodies Short lasting Ex. Antibiotics and breast milk Active Immunity You make your own antibodies to fight the pathogen Long lasting Ex. Vaccines and getting the disease