Whats the difference between the h. Pylori breath test and the h. Pylori blood test?

Different. The breath test looks for presence of the active infection and presence of the bacteria in your stomach. It can be used to test to see if you are cured after treatment. The blood test checks for an antibody that is produced by your body after being exposed to the bacteria. It, however, will always be present and cannot be checked to see if you cured the infection.