Is Herpes Always Contagious? An Expert's Perspective

Both HSV-1 and HSV-2 are more contagious when there are sores present, but they can also be transmitted even when there are no symptoms or visible signs. To prevent the spread of herpes, the consistent and correct use of condoms is the best way to protect against genital herpes and other sexually transmitted infections (STIs). Studies have shown that asymptomatic transmission occurs between 1% and 3% of the time in patients with genital HSV II infections. Cold sores are usually caused by HSV I.People who have HSV I are likely to be infected with HSV II, the most common cause of genital herpes.

A large study showed that if one partner has herpes and the other is not infected, treating the infected partner with suppressive therapy can prevent the transmission of symptomatic herpes in more than 90% of cases. This is an option for couples who are interested in unprotected sex or who are planning to become pregnant. Infections are transmitted by contact with HSV in herpes lesions, mucosal surfaces, genital secretions, or oral secretions. However, receiving oral sex from someone with an oral HSV-1 infection can cause a genital HSV-1 infection. Herpes is most contagious when the sores are open and moist, because fluid from herpes blisters easily spreads the virus.

But herpes can also “break off” and spread to others when there are no sores and the skin looks completely normal. Taking a small dose of anti-herpetic medicines every day can reduce the number of outbreaks by more than 90%. When HIV damages a person's immune system, they are more likely to transmit the herpes simplex virus asymptomatically. A person with herpes who is transmitting the virus can be contagious even if they have no lesions or symptoms, which is why the population of patients with genital herpes caused by HSV I is believed to be increasing. Sometimes, herpes can be transmitted in a non-sexual way, such as if a parent with cold sores kisses you on the lips. Although women with genital herpes may be offered antiviral medications late in pregnancy and until delivery to reduce the risk of a recurrent herpes outbreak, third-trimester antiviral prophylaxis has not been shown to decrease the risk of transmission of herpes to the newborn.

Herpes medications may not work as well in patients who are very immunosuppressed and who have been treated with these medications for a long time. Many people with herpes don't notice the sores or mistake them for something else, so they may not know they're infected. HSV-1 usually causes oral herpes and HSV-2 usually causes genital herpes. Each strain prefers to live in its favorite area. The correct and consistent use of latex condoms can reduce, but not eliminate, the risk of transmitting or acquiring genital herpes, since the spread of the virus can occur in areas that are not covered by a condom.

If you are starting a new relationship and you know that you have a herpes simplex infection, you should let your partner know before having sex. When you get HSV-1 or HSV-2 on or around your lips, mouth, and throat, it's called oral herpes. The Centers for Disease Control and Prevention (CDC) estimated that there were 572,000 new genital herpes infections in the United States in a single year. Genital ulcer disease caused by herpes facilitates the transmission and acquisition of HIV infection through sexual intercourse. The risk of contracting HIV is estimated to increase 2 to 4 times if people with a genital herpes infection are exposed to HIV through the genital tract.