There's the poo test and a breath test.. beyond that I'm unsure. The breath test seems less available, maybe. Consider the following before alarming yourself though. H pylori, if asymptomatic, may be at a level of what some in the medical field deem best left alone. The goal in some treatments seems to beat it down rather than eradicate it. Rationale seems to weigh cost\benefit of slaughtering all the good stuff to get the bad when the bad might not do much beneath a threshold. I'm no authority. The subject, I do think is worth reading about and it doesn't appear there's a clearly advised plan for the infected asymptomatic majority.