Here's the truth about 8 common myths about genital and oral herpes, which can help you determine if you've been infected with either herpes simplex 1 or herpes simplex 2.

Nearly two-thirds of the global population is infected with herpes simplex virus type 1 (HSV-1), according to a recent report released by the World Health Organization. Researchers affilated with the organization estimated that 3.7 billion people under the age of 50 are infected with HSV-1, the type of herpes most people associate with cold sores on the mouth.

Another 417 million people worldwide aged 15-49 have HSV-2, the type most often thought of as a sexually transmitted infection (STI), causing sores to appear on the genitals. But here's the truth: 140  million adults have genital infections caused by HSV-1, meaning half a billion people could sexually transmit either virus.

While this news may be shocking, don’t panic. Herpes has been seriously stigmatized for years, but it's also incredibly common, as these statistics show. The fact is, if you don't have one type of herpes already, you're very likely to be exposed to it eventually. Below, we take apart eight big myths about this common infection, so you can get a better sense of whether any sore or lesion you've noticed on either your mouth or genitals might actually be caused by herpes.

Myth: Cold sores and genital sores are way different

Many people wrongfully believe that cold sores don't count as “real” herpes, Raquel Dardik, MD, clinical associate professor at NYU Langone’s Joan H. Tisch Center for Women’s Health, explains to Health. This misconception stems from the general patterns of the two types.

For most people, HSV-1 tends to affect their mouth, while HSV-2 usually manifests on the genitals. But either virus can affect either body region; all it takes to spread is skin-to-skin-contact.

Let's say you touch an infected person's genitals with your mouth while they're shedding the virus, but there's no genital-to-genital touching. You can then be infected with either HSV-1 or HSV-2 (whichever your partner has) and go on to develop lesions at the site of the infection (in this case, your mouth).

Myth: I’ve never had an outbreak, so I definitely don’t have herpes

Unfortunately, the lack of a visible outbreak doesn’t mean you’re herpes-free. Many people infected with the virus never experience an outbreak, Mary Rosser, MD, PhD, director of obstetrics and gynecology at Montefiore Medical Center in New York City, tells Health. And when they do, it frequently isn’t recognized. This explains why, according to the US Centers for Disease Control and Prevention (CDC), 87.4% of infected individuals have no clue.

“Outbreaks can be very mild and even confused with things like heat rash, jock itch, yeast infections, [and] allergic reactions,” Fred Wyand, director of communications for the American Sexual Health Association (ASHA), tells Health. “So while some cases do involve pronounced symptoms, most never do.”

Myth: I got tested for STDs recently, so I know I'm in the clear

Even if you’ve been hyper-responsible about getting tested, that's irrelevant when it comes to herpes. The CDC doesn't recommend testing for the virus, so a herpes test is typically not included in the routine STI panel. This is because a blood test for herpes only tells you whether you’ve been exposed to the virus, explains Dr. Dardik. "And a positive result only "raises a whole host of concerns of 'when?' and 'how?' and 'where?,' which are not answerable by that test. It's not going to change your management and provide more answers, which is why it’s not routinely offered," she adds.

Complicating things further is that the herpes virus which infects the mouth and genitals is very similar to the herpes virus that causes shingles and chicken pox. If you've had either of those illnesses, your results may be skewed, says Dr. Rosser.

So how do you know if you have herpes? The best way to tell is to wait until you have a lesion or outbreak of lesions. Then your doctor can run tests on the lesions to determine whether they are in fact herpes, and what type you're dealing with.

Myth: Without a visible outbreak, herpes isn't contagious

Since outbreaks aren’t always obvious, it’s not always clear when you’re contagious. “There are a few days a year when herpes is active and possibly transmitted without any symptoms present,” explains Wyand. This is known as viral shedding. “This doesn't happen on most days, but it's tricky, because there's no real way to know.”

All this sounds really scary, but what it boils down to is the importance of practicing safe sex. While the risk of transmission will never be zero, there are some steps you and your partner can take to significantly reduce the risk of transmission: avoiding sex during an outbreak, using condoms. The partner with herpes can also go on suppressive therapy (antiviral medications like valacyclovir, brand name Valtrex).

Dr. Rosser agrees that condoms are your best friends for any kind of sex. "People still look at me like I have two heads when I suggest condoms for oral sex," she says. "But if there's any question, then use them."

Communication is not only essential when it comes to having great sex, adds Dr. Rosser, but also when preventing the spread of herpes. If you're infected, be honest and considerate—let your partner know.

Myth: People with herpes must be promiscuous

The reality of any STI is you don’t need to sleep around to get infected. This is especially true for herpes, considering there’s such a large population of "asymptomatic carriers," says Dr. Dardik. “While having more partners obviously increases your risk of any kind of any kind of sexually transmitted infection, the reverse doesn’t always hold,” she points out. In other words, all it takes is one partner.

Myth: I can’t have kids if I have herpes

"When my patients find out they have herpes, they often ask me, 'Oh my god, can I still have children?'" shares Dr. Rosser. The answer? Absolutely. Herpes doesn’t affect your fertility in any way and there are plenty of safe delivery options to ensure the virus isn’t transferred to your baby, she says. Still, genital herpes can increase the risk of miscarriage, preterm birth, or in rare cases, a potentially dangerous infection in newborns if the mother is experiencing symptoms at the time of birth.

Myth: If my partner suddenly shows signs of herpes, they must have cheated 

If you’ve been monogamous with your partner for 5, 10, even 20 years, then out of the blue they have a visible herpes outbreak, the only logical explanation is cheating, right? Not necessarily. Similar to HIV or chicken pox, herpes has viral latency, or the ability to lie dormant in your body for years without showing any signs.

“You could have been infected in your 20s, and the virus might show up again when you're 40,” says Dr. Dardik. “The virus stays in your system even if it isn’t active.” In some cases, people won't have any kind of outbreak unless it's triggered by a significantly stressful life event, like another illness.

Myth: We're all doomed to get herpes

Herpes may be super common, but that doesn't mean you'll definitely get it. Sure it's unsettling that so much of the population has the virus, but just because someone has the disease doesn’t mean they’re going to transmit it, says Dr. Dardik. In fact, most outbreaks usually occur in the first or second year following infection, and after that, your body tends to suppresses the virus for the most part.

Having herpes or dating someone with the virus doesn't mean your sex life is doomed, either. Smart safe sex practices can cut the risk of spreading or catching the virus to nearly zero.

And finally, if you do have herpes, there are effective treatments for helping with outbreaks, so you shouldn't feel hopeless. "Many people have this idea that people with herpes are dirty and taboo, but they're not," says Dr. Rosser. "It’s very common. Anyone can get herpes."

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