I have had this "virus" for a little over two years. I picked it up eating out at restaurants. A first it was my upper chest that boated up and could not sleep at nite, had to roll over from side to side constantly. Now it stays mostly in the lower bowel and am able to massively burp up the bloated air. I gave up eating out at restaurants, take many charcoal pills 4 five times per day a am slowly getting better. Also, I now have a diet of ice cream, malts, milk, potatoes and other non greasy starches. Sour cream with chips ,blintzes, puding and jello etc. When I try to eat out or have regular food it re-agrivates the condition. I think it was caused by an famous ice cream shop where they do not wash out the ice cream machines very often. No doctor was able to help me.
H. pylori is one of the most common chronic infections ever. It's said about 50% of people have it, but only some have symptoms. Search a little. Transmission is not well known. H. pylori causes upper abdominal bloating, burping...but not really diarrhea. So, you might also want to have stool test for parasites and for Clostridium difficile toxin.
What is an H. pylori infection and where does one get such a thing?
You maybe need a breath test for H. pylori infection of stomach, and stool test for parasites.