 [ Symptoms ] could i have genital herpes and not know it [ Disease ] unless no one has ever kissed you and unless you have never had sex it is possible that you have picked up a herpes virus oral herpes usually caused by the herpes simplex virus type 1 hsv 1 shows up as cold sores or fever blisters on the mouth even a casual peck on the lips from someone with a cold sore can give you the virus that is why it is so common as many as 50 to 80 of adults in the u s have oral herpes genital herpes most often caused by the second type of herpes virus hsv 2 is less common but plenty of people still have it roughly one in five u s adults has genital herpes but up to 90 of those who have it do not know they are infected you could be one of them