Infection Characteristics and Transmission Patterns of Helicobacter pylori in Families of Early Gastric Cancer Patients

Background : The prevention and control strategies for Helicobacter pylori (H. pylori) are gradually shifting from individual-based care to family-based management approaches. However, the infection status, risk factors, and transmission dynamics of H. pylori within families of early gastric cancer (EGC) patients remain to be elucidated. Methods : This family-based study was conducted at Nanjing Drum Tower Hospital from June to December 2024, targeting cohabiting fam1ily members of EGC patients. Inclusion criteria required family members to have lived together for at least 10 months per year, with a minimum of two members and no upper limit on household size. An infected household was defined as having at least one member testing positive for H. pylori. The study investigated household H. pylori infection status, associated risk factors, and transmission patterns. Results : Among the 125 enrolled households, 21 (16.8%) consisted of 2 members, 57 (45.6%) of 3 members, 36 (28.8%) of 4 members, 5 (4.0%) of 5 members, 5 (4.0%) of 6 members, and 1 (0.8%) of 7 members. Of these households, 4 households (3.2%) showed no infections, 84 households (67.2%) had partial infections, and 37 households (29.6%) had full-family infections. Among the households, 79 (55.8%) included one couple, 34 (27.2%) included two couples, and 2 (1.6%) included three couples, while 10 households (8.0%) included only a husband or wife. In 153 couples, 67 couples (43.8%) had both partners infected, 22 couples (14.4%) had neither partner infected, and in the remaining couples, only one partner was infected. At the household level, higher annual household income was associated with a lower risk of infection (OR = 0.26, 95% CI: 0.08–0.80, p = 0.019). At the individual level, older age, occupations such as farming or freelancing, exposure to infected household members, and a history of gastrointestinal discomfort were significant risk factors for infection (p < 0.05). At the spousal level, infection rates increased with the duration of cohabitation (p < 0.05). Conclusion : The infection rate in families of EGC patients was higher than in the general population, and EGC patients are likely the primary source of transmission within these households. Monitoring and eradicating Helicobacter pylori infection in family members of patients with early gastric cancer is very important for preventing and controlling the occurrence of gastric cancer.