Herpes simplex viruses -- more commonly known as herpes -- are categorized into two types: herpes type 1 (HSV-1, or oral herpes) and herpes type 2 (HSV-2, or genital herpes). Most commonly, herpes type 1 causes sores around the mouth and lips (sometimes called fever blisters or cold sores). HSV-1 can cause genital herpes, but most cases of genital herpes are caused by herpes type 2. In HSV-2, the infected person may have sores around the genitals or rectum. Although HSV-2 sores may occur in other locations, these sores usually are found below the waist.
It should not be confused with conditions caused by other viruses in the herpesviridae family such as herpes zoster, which is caused by varicella zoster virus. The differential diagnosis includes hand, foot and mouth disease due to similar lesions on the skin. Lymphangioma circumscriptum and dermatitis herpetiformis may also have a similar appearance.
Oral herpes is also known commonly as cold sores and fever blisters but is different entity from oral canker sores although canker sores may sometimes be associated with HSV infection. Canker sores occur solely inside the mouth. Oral herpes occurs inside and around the mouth. Most of the time HSV-1 causes mouth symptoms and in a minority of cases it may also be responsible for genital symptoms. The opposite is true for HSV-2 – it causes genital symptoms in the majority of cases while only a few cases of HSV-2 infection will result in mouth symptoms. HSV-1 infection may be seen in all ages, including children, but when genital herpes is seen in children, sexual abuse needs to be a consideration.
'Using condoms or dams can help to protect against STIs, but herpes can also be passed on by skin-to-skin contact with the affected area, so it’s strongly recommended that you don’t have sex during this time,' she adds. 'This includes direct genital contact or skin-to-skin contact with the affected area, and doesn’t have to be penetrative sex,' says O’Sullivan.