﻿ Cold Sores (Nongenital Herpes Simplex Infections) Symptoms, Causes, Treatment - What are the risk factors for herpes simplex infections? - MedicineNet

Herpes Simplex Infections (Non-Genital) (cont.)

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What are the risk factors for herpes simplex infections?

Exposure to someone with cold sores increases the risk of getting oral herpes. HSV is most contagious when the person has mouth sores or blisters on the lips. The virus can also shed from saliva when there are no visible lesions. Therefore, a person can be contagious without having an outbreak. Direct contact with the virus, from kissing or sharing personal items, will increase the chance of getting infected with HSV.


Medical conditions or treatments that weaken a person's immune system can increase the risk of severe complications from the virus. These include HIV, cancer, chemotherapy, and steroids.

What are the possible complications of oral herpes (cold sores)?

Herpes can be spread from one area to another on the same person, which is called "autoinoculation." For example, touching a cold sore on the lip can cause herpes of the finger (herpetic whitlow). Autoinoculation occurs most commonly at the time of primary infection, when viral shedding is high and the immune system is still gearing up to contain it. The antibodies that are made after primary infection are usually -- but not always -- successful in preventing autoinoculation during recurrent attacks.

A more serious complication is ocular herpes (involvement of the eye), which is characterized by lesions and severe pain around the eye. Ocular herpes is also caused by autoinoculation. If not treated, ocular herpes can lead to serious damage or even blindness.


In immunocompromised people, such as those receiving chemotherapy, severe outbreaks of herpes may occur. Colds sores may spread to large parts of the lower face or invade organs. Antiviral therapy is used to prevent or lessen such attacks.

In a few people, outbreaks of herpes will be associated with erythema nodosum. Erythema nodosum is a nonspecific skin reaction characterized by red and painful skin lumps that usually appear on the front side of the legs. This condition can be caused by many inflammatory and infectious diseases, including herpes virus infections. Erythema nodosum can be self-limited and resolve on its own in three to six weeks. Treatment of the herpes episode usually hastens the resolution of erythema nodosum.

Medically Reviewed by a Doctor on 2/18/2015

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