Herpes 1 is a reference to herpes simplex virus 1, one of two variations of the herpes simplex virus. Herpes simplex 1 is an extremely common virus, possibly only second in commonality to the virus that causes a "cold". It's estimated that ninety percent of adults are infected with herpes simplex 1. When a herpes simplex 1 infection causes symptoms, the symptoms typically are an outbreak of blisters about the mouth that are often referred to as cold sores. Herpes simplex 1 can also affect the genital region, though this is not common. A herpes 1 infection is not a threat to overall health.