H. pylori antibodies are a type of IgG antibody produced in the body of a person who has been infected with H. pylori, indicating that the person has been infected or is currently infected with H. pylori. Generally, when the body is infected with H. pylori, it stimulates the body’s immune system to produce antibodies, including IgM and IgG antibodies (both of which are immunoglobulins), of which the IgG antibody has been present for a longer period of time, and can be detected by blood tests. The presence of antibodies indicates that the subject has been or is currently infected with H. pylori. Further determination of ongoing infection requires a C13 and C14 breath test. After the presence of H. pylori antibodies is detected, one should seek medical attention under the guidance of a physician to avoid delays.