H.pylori infection. This is a serology test, which is cheap and convenient to perform. These are antibodies response to H.pylori bacteria, which varies from person to person. It does not means that you have active H,pylori infection. If it is positive it has to be confirmed by endoscopic biopsy or urea breath test (UBT) before starting the treatment.
Not necessarily. It means that you were at one time infected with H pylori. Being infected with H pylori does not mean that you have any disease due to it. Most people who have the infection, have silent H pylori infection See this site for more info. http://www.mayoclinic.org/diseases-conditions/h-pylori/basics/definition/CON-20030903.