BackgroundMore than 90% of gastric cancer cases are caused by Helicobacter pylori infections. To prevent gastric cancer, an H pylori test‐and‐treat strategy targeting young people has been implemented in various places in Japan. In this study, we evaluated the effectiveness of an H pylori test‐and‐treat strategy for second‐year junior high school students in Takatsuki City.Materials and MethodsIn 2014‐2017, a urine‐based H pylori test was used for initial screening. The final infection status was determined by a 13C‐urea breath test (13C‐UBT). Successful H pylori eradication was confirmed by 13C‐UBT 3 months after treatment. First‐line eradication therapy was changed from 10 mg of rabeprazole, 750 mg of amoxicillin, and 200 mg of clarithromycin twice daily for 7 days in 2014 to 20 mg of vonoprazan, 750 mg of amoxicillin, and 200 mg of clarithromycin twice daily for 7 days in 2015‐2017. Second‐line eradication therapy included 10 mg of rabeprazole, 750 mg of amoxicillin, and 250 mg of metronidazole twice daily for 7 days.ResultsIn total, 8067 of 13 055 students participated this project and 206 students were diagnosed with H pylori infection. The success rate of first‐line therapy was 45.9% in 2014 and 83.8% after the revised first‐line therapy was administered. The final eradication rate was 98.5%. There were no severe side effects.ConclusionOur results support the use of the H pylori test‐and‐treat strategy for junior high school students as a safe approach for the prevention of gastric cancer. H pylori eradication therapy with vonoprazan could be a standard therapy in children.