Herpes on the buttocks is still genital herpes. You shed from the area of the actual lesions when you have them as well as also from the entire anogenital area. In between obvious lesions, you shed the virus periodically from the entire anogenital area and not from the area where you typically so far have had obvious lesions at. The skin on the buttocks is too thick for the virus to shed from without obvious lesions present. so what this means is there is absolutely no difference between your infection and someone who typically gets obvious lesions on their actual genitals. make sense? so if your partner doesn't have hsv2, avoid sex whenever you have symptoms, not just try to have them avoid coming in contact with the lesions on your buttocks when you have them.
grace
How were you diagnosed as having genital herpes?
Yes indeed, you can transmit it from having genital sex, even if your lesions occur on your buttocks. You also can transmit via viral shedding, where the virus is active but there are no symptoms.
Are you taking suppressive therapy? Condoms? Most importantly, has your partner been tested for herpes?