The most common reason that people develop cold sores on their mouths is due to becoming infected with HSV-1. (4) HSV-1 usually causes cold sore breakouts around the lips or mouth, or what some people describe as “fever blisters.” Someone can become infected with HSV-1 starting as a child, and then the virus can lay dormant in the body until the immune system is weakened, at which point symptoms can surface.
^ Xu, Fujie; Fujie Xu; Maya R. Sternberg; Benny J. Kottiri; Geraldine M. McQuillan; Francis K. Lee; Andre J. Nahmias; Stuart M. Berman; Lauri E. Markowitz (2006-10-23). "Trends in Herpes Simplex Virus Type 1 and Type 2 Seroprevalence in the United States". JAMA. 296 (8): 964–73. doi:10.1001/jama.296.8.964. PMID 16926356. Archived from the original on 2010-04-24.
The most effective method of avoiding genital infections is by avoiding vaginal, oral, and anal sex. Condom use decreases the risk. Daily antiviral medication taken by someone who has the infection can also reduce spread. There is no available vaccine and once infected, there is no cure. Paracetamol (acetaminophen) and topical lidocaine may be used to help with the symptoms. Treatments with antiviral medication such as aciclovir or valaciclovir can lessen the severity of symptomatic episodes.
'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.