The seroprevalence trend of Helicobacter pylori infection in Gombe, Nigeria: a 5-year retrospective study by Ibrahim, Yakubu, Famoriyo, Lateef, Muhammad Sani, Fatima, Basri, Nurul Iftida, Jamil Mohd, Amilia Afzan, Abdurrahman, Muhammad Shuaibu, Abdullahi, Idris