Explain what an antibody is in your own words?

An antibody is when the blood from the blood is formed to neutralize the antigen (a toxin or other foreign substance in the body). Antibodies come together to fight off an antigen which the body recognizes as usual. Examples of antigens are viruses, bacteria, unfamiliar substances in the blood. The leukocyte (white blood cell) goes around the blood and body fluids and is part of the antibodies which form to fight off the pathogen; there are 2 types of white blood cells which are T and B cells, the B cells are the ones which produce the antibodies.

What is the antibody role in preventing reinfection in diseases?

The antibody has no role what so ever in controlling viral infectious diseases. However the antibody does have a major sort of role with the resolution of bacterial infectious diseases. There are some cells around the body which help with the bacterial infection like phagocoyte white is capable of absorbing the bacteria. Another cell is the macrophage which can engulfs and digest unfamiliar substances (these are a type of white blood cells).