The habit of family meals makes the infection rate of Helicobacter pylori high in China, which is also the main cause of reinfection of Helicobacter pylori. Eating together can easily cause family members to be infected with Helicobacter pylori. We used a real-world study to understand the risk factors, epidemiological characteristics, and safety and effectiveness of eradication therapy for helicobacter pylori infection in family-based screening and treatment.

Helicobacter pylori infection is a worldwide problem, which is the main cause of gastric cancer. The habit of sharing meals in the family is one of the factors contributing to the high infection rate of HP in China, as well as the main cause of reinfection of HP. Sharing meals can easily cause family members to be infected with HP.Family members live together, eat together, share tableware and other behaviors through the "mouth to mouth" transmission of Helicobacter pylori may be infected with each other, is also one of the reasons for the eradication of many patients after re-infection.At the same time, repeated infection and treatment of Helicobacter pylori will increase the difficulty of Helicobacter pylori reeradication.As a family unit, to study the status of our country family helicobacter pylori infection, epidemiological characteristics, infection risk factor, the different schemes, such as the safety and efficacy of treatment to take measures to reduce the infection rate is of great significance to prevention and treatment of gastric cancer.

Inclusion Criteria:

• Community population over 3 years old who signed the informed consent.
• at least 2 people in the family.
• living together for at least 10 months each year in the past 5 years except child aged below 5.

Exclusion Criteria:

• PPI drugs such as esomeprazole、pantoprazole、 rabeprazole,、lansoprazole、famotidine and H2 receptor antagonists were taken within two weeks.
• antibiotics、bismuth agents or traditional Chinese medicine with antibacterial effect were taken within four weeks
• There are other factors that researchers think are not suitable for participation

Community population aged above 3 years in family unit,The family unit is determined by actual living together rather than household registration relationship, with at least 2 people in the family and living together for at least 10 months each year in the past 5 years.