Herpes simplex I and II spread very easily when sores are present, but occasionally they are spread by symptom-free persons carrying the viruses. People catch herpes through intimate physical contact, including kissing and sex. Herpes I and II sores can spread between the mouth and genitals of different individuals during oral sex. Condoms and dental dams probably reduce the chances of transmission during sex. To keep herpes infections from spreading to other parts of your body, do not scratch or irritate fever blisters, and see your doctor as soon as you notice an eruption.
Many people think that herpes simplex outbreaks are related to emotional stress.
Practicing such stress-reduction techniques as meditation or yoga, or learning better coping skills, may help prevent reactivation of old herpes infections.