HSV2 is spread by sexual or skin-to-skin contact, and can be passed on during vaginal, oral or anal sex. It can occur anywhere on the genitals or surrounding areas. A person who has had cold sores on their mouth (HSV1) can cause genital infection in a partner by having oral sex. It is important to realise that HSV2 can be spread when there are no blisters present- this is called viral shedding. The more often a person has flare-ups, the more virus they tend to shed in between the flare-ups.