Herpes simplex I is from the herpes simplex virus family and causes sores around the mouth and lips which are sometimes called fever blisters or cold sores. This virus is likely to reoccur more often than herpes II and is transmitted through oral sex. Herpes simplex I can sometimes cause genital sores as well.

More than 90% of the population is positive for herpes I but many people don’t know they are positive, because most people with herpes do not have outbreaks. The average rate of recurrence is four to five times in the first two years after being infected.

Herpes simplex I is very contagious and is transmitted through the direct contact between the contagious area and broken skin via salvia.

If you or your partner has herpes I in the form of sores or cuts around the mouth, genitals or anus, there is an increased risk of passing it onto your partner through oral sex. This is because the herpes I virus travels in salvia and can infect your partners through breakages in your skin.

Herpes usually does not lead to complications. Although, outbreaks are common and can be painful, they are more-so in individuals with a weak immune system. It can also infect the eyes, which left untreated can lead to loss of vision. Herpes simplex I can cause a higher risk of miscarriage, as well as premature labour. It is also possible for herpes I to be passed onto a baby during delivery. Herpes simplex I in babies can be very serious.

Herpes Type I usually causes small, painful blisters on the lips, mouth, gums or skin around the mouth, commonly known as cold sores. Herpes simplex II causes painful blisters on the genitals and surrounding areas. Although both highly contagious, type I and II are different strains of the virus within the same family.