Is h pylori deadly?

Yes. Helicobacter pylori does not kill directly, but it is culprit for a large percentage of stomach cancers and other tumors. The ulcers that it causes still kill the unwary as well. Best to have the nasty little creatures eradicated as required -- which thankfully we can now do!
H pylori. Definitely not. It's a bacteria recognized in the late 1980s that is associated with peptic ulcer disease. What's interesting is that many people may have it and yet have no ulcer disease. So, it's only worth looking for if you are suspecting an ulcer.

Related Questions

Is h. Pylori deadly or just causes ulcers? Can someone get fever, chills, aches, like the flu, from an h. Pylori infection?

Ulcers and cancer. H pylori causes ulcers, however, long standing infections are linked to stomach cancer. People usually do not get flu like symptoms from h pylori.