Helicobacter pylori is a bacterium that colonizes the human stomach and is the risk factor for severe gastroduodenal diseases, such as gastric cancer, gastric lymphoma, autoimmune gastritis and peptic ulcer. H. pylori activates Nod-like and Toll-like receptors, and usually promotes gastric T-helper 1/17 (Th1/Th17) immune responses. Several bacterial factors, such as CagA, VacA, HP-NAP, the lipoprotein HP1454, and HP0175 can shape Th1/Th17 response by regulating T-cell receptor signaling. However, the host immune response to the infection is ineffective, the bacterium persists, and the inflammation continues for decades. Altogether the investigations performed so far highlight the crucial roles played by both H. pylori and the immunopathological responses of the host in the pathogenesis of gastric cancer, gastric MALT lymphoma, and gastric autoimmunity. It also suggests the strong and urgent needing for an anti-H. pylori vaccine in order to prevent both the infection and the severe diseases due to H. pylori. The present article is a review of the most relevant literature on inflammation, immunity, and vaccines against H. pylori, published in the middle of the COVID-19 war between April 2020 and March 2021.