Patients can check whether they are infected with Helicobacter pylori by observing their own symptoms or going to the hospital for serologic examination and breath test. H. pylori is a kind of bacteria parasitized in the human stomach, and its infection is closely related to the occurrence of chronic gastritis, gastric ulcer, gastric cancer and other diseases. Patients may experience symptoms such as acidic belching, nausea and vomiting, abdominal pain and bloating, and bad breath after infection. If patients experience the above symptoms, H. pylori infection may be considered. However, most patients may not have obvious symptoms after H. pylori infection. To check whether a patient is infected with H. pylori, it is best to go to the hospital for serologic examination, breath test, rapid urease and other tests to confirm the diagnosis. H. pylori can produce a large amount of urease, which breaks down urea to produce carbon dioxide, and can therefore be examined by a carbon 13 or carbon 14 breath test. The patient is asked to swallow a capsule containing carbon 13 or carbon 14 labeled urea, and after a period of time, the breath exhaled by the patient is examined for the presence of radioactive markers to determine whether or not there is an infection. It is recommended that the patient undergoes the appropriate tests under the guidance of a medical professional before determining whether he/she is infected with H. pylori. Patients with a positive H. pylori test are advised to seek prompt medical attention and actively receive treatment to avoid delaying their condition.