Antibodies are the body's
natural defense against foreign materials. After a month or two, if you've been infected
HIV, antibodies appear in your blood. The gap between infection and the development of antibodies is called the window period. During this time antibody tests give false negatives.
There are two methods of antibody tests: ELISA or the enzyme immunoassay, and the Western blot test. The ELISA method is commonly the first screening. After the
ELISA test produces a positive result, the the Western blot test is performed. Antibody tests are inexpensive and has a 99% accuracy rate.
