Skip to Content
Home > Health Information > Health Library > Herpes simplex
Herpes simplex is a virus that can cause painful blisters and sores. The virus usually affects the skin and the thin layers of tissue that moisten, lubricate, and protect certain parts of the body (mucous membranes).
The two main types of herpes simplex viruses are type 1 (HSV-1) and type 2 (HSV-2). Both types of the virus can cause sores on the lips (cold sores) and sores on the genitals (genital herpes). HSV-1 more often causes cold sores. HSV-2 more often causes genital sores. The viruses are transmitted by direct contact, such as touching a sore directly or through sexual contact.
A herpes infection may cause only a single outbreak of sores. But in many cases the person will have recurrent outbreaks. Recurring infections can be triggered by factors such as stress, fatigue, sunlight, or another infection, such as a cold or flu.
Treatment can reduce the number and severity of outbreaks but cannot cure the infection.
Herpes zoster, another form of herpes virus, causes chickenpox and shingles.
Current as of: February 26, 2020
Author: Healthwise Staff
Medical Review:Sarah Marshall MD - Family Medicine & Adam Husney MD - Family Medicine & Martin J. Gabica MD - Family Medicine & Kevin C. Kiley MD - Obstetrics and Gynecology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2020 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.
You'll find Decision Points to help you answer questions about:
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.
See important information from Billings Clinic on Non-discrimination and Interpreter Services.
Billings Clinic is proud to be an equal opportunity/affirmative action (EOE/AA) e-verify employer.