No one can tell you how long you had it. Since men cannot be tested and men are usually the carriers, it is possible he always had it. Most people don't know they have the high risk strains since there are no symptoms until pre-cancerous cells are found. Most sexually active people have multiple strains. The odds are always better that a new diagnosis is from a recent encounter than from the past but there are exceptions where women get a bad pap from an encounter years/decades ago. There just isn't any way to play detective with HPV and point to a a partner or sex act as the cause. At this point, you and your husband share this virus. Most people do clear the virus (make it dormant) but some do not and no one knows why. When people clear it, they aren't infectious but not everyone remains non-infectious forever. Some become infectious years later and the medical community does not know why but some of us think it has something to do with one's immune system. Certainly, smoking cigs, drinking alcohol, stress, lack of enough sleep, living an unhealthy life, etc all contribute to a weakened immune system. Assume for now that you should get tested every year. Your husband may want to see a urologist for preventive screening but without any symptoms, he may not ever need any medical attention.