My Partner's Cold Sores Gave Me Genital Herpes

Many people are not aware that "cold sores" or "fever blisters" are the symptoms of oral herpes. Nor do they realize that the virus that causes these sores is extremely closely related to the virus that causes genital herpes. That's why people with oral herpes often unknowingly transmit their cold sores to their partner's genitals during oral sex. Ironically, the person with cold sores may even unfairly blame their partner for getting infected. They may not realize they are the source of their partner's infection. 

Oral herpes and genital herpes are misleading names. It used to be said that HSV-1 usually causes oral herpes and HSV-2 usually causes genital herpes. However, the truth is that either virus can infect either location. In fact, a growing percentage of genital herpes infections are caused by HSV-1. Some scientists estimate that more than half of new genital herpes infections are caused by HSV-1 rather than HSV-2. This may be because there is some evidence that HSV-1 — usually associated with oral herpes — may actually be more infectious than HSV-2. That means that people with cold sores may be at higher risk of transmitting herpes to their partners than people with genital infections, although they probably neither realize it nor worry about it.

Another reason that genital HSV-1 is becoming more common is that cold sores are actually on the decline. There is some evidence that individuals with a childhood history of recurrent cold sores are less likely to be infected with genital herpes caused by the "cold sore virus." They can still be infected, but their childhood infection seems to provide some protection.

Common wisdom and some "experts" often say you can't be infected with herpes twice. However, research has shown that concurrent herpes infections are possible. Multiple studies have demonstrated that people can have oral herpes and genital herpes infections caused by the same type of herpes virus at the same time.

In other words, cold sores aren't protection against a genital herpes infection. That's true whether both infections are caused by HSV-1, both infections are caused by HSV-2, or one infection is caused by each. These are all possibilities that can occur. 

What does this mean, from a practical perspective?

If you or your partner are infected with herpes or think you might be, it's important to use barrier methods during sex. That's something that's as true for oral sex as it is for intercourse. If a person has cold sores on their lips, they can transmit them to their partner's mouth during kissing. They can also transmit them to their partner's genitals during oral sex. Similarly, a genital HSV-1 infection can be transmitted to a partner's genitals or their mouth. (HSV-2 oral infections are possible. However, it is somewhat less likely that a genital HSV-2 infection would be transmitted to the mouth. HSV-2 appears to prefer the genitals as a site of infection. HSV-1 is a far more equal opportunity virus.)

Herpes infections are spread from skin-to-skin. That means that barriers aren't 100% protective. However, condoms and other barriers can reduce the risk of transmitting herpes to a partner. In addition, if a person knows they are infected, there are other options to reduce risk. Suppressive therapy doesn't just reduce the frequency of outbreaks. It also reduces the likelihood of transmission during sex. Regular use of valacyclovir and other herpes anti-viral medications has been shown to reduce viral shedding and the risk of herpes being passed to a partner.​

Herpes testing isn't a standard part of sexual health care. The stigma associated with herpes infection is severe enough that many doctors are reluctant to test people who do not have symptoms. They may also be concerned about false positive or false negative testing. 

However, if you are at risk for herpes infection and want to know your current status, you can always ask for a test. Type-specific herpes blood tests can be performed at most major medical laboratories. They're not 100 percent accurate, but they can still provide useful information in certain situations. 

If you have recently developed genital herpes, and are dealing with a partner who is upset because they think you have cheated on them when you haven't, you should talk. It may be a good idea to ask whether they have ever had a cold sore. If so, they could be the source of your genital herpes infection. Even if they have never had a cold sore, if they are asymptomatically infected with oral herpes they may have put you at risk. Herpes and other STDs can be transmitted even by someone who has never had symptoms. That is why conversations about blame are pointless unless both of you were tested before starting your relationship — and even then it can be counterproductive.

There is an unfortunate stigma about genital herpes infection that is not usually present for cold sores, even though the infections are extremely similar. In part, this is because many people get cold sores starting in their early childhood. The virus is often transmitted by casual affection from a parent or relative. However, when the same infection becomes associated with sex, people suddenly want to judge it more harshly. It doesn't matter how illogical that may be.

Ignorance of the similarities between the two primary herpes viruses is a big problem. It means that even those people who have cold sores often stigmatize people with genital herpes and freak out over a partner's genital herpes infection when they have no concerns about their own oral infection. I have gotten several e-mails from people with a history of cold sores who, when they found out that their partner had been recently diagnosed with genital herpes, insisted that their partner must have been cheating on them and became furious or terrified that they might have been exposed to the virus. None of those people realized that their cold sores could have caused their partner's genital herpes. They were all shocked to learn that cold sores can lead to genital herpes infections when the virus is passed on during unprotected oral sex.

The stigma associated with infection can make it extremely stressful to be diagnosed with genital herpes — or to be dating someone who is diagnosed with genital herpes. However, it isn't helpful to panic or to judge. Instead, both of you should focus on learning everything you can about the herpes viruses and doing your best to keep from transmitting them to anyone else. Try to think of the infection as a mild chronic illness. After all, for most people, that's exactly what it is. If you can hold on to that, instead of the stigma, herpes can become much easier to live with.

If you do have either cold sores or genital herpes, remember that the risk of transmission to a partner can be reduced by using suppressive therapy and practicing safe sex. Also keep in mind that, although the risk of infection is greatest during or immediately prior to an outbreak, you can still transmit the herpes virus even when no sores are present.