Is Mono an STD?

Infectious mononucleosis (mono) is highly contagious and is often caused by a herpes virus known as the Epstein-Barr virus (EBV). Less commonly, it can also be caused by other viruses like the cytomegalovirus (CMV). While mono can be transmitted through sexual contact, it is not strictly a sexually transmitted disease. Popularly known as the "kissing disease," mono can also be spread through saliva, sharing drinks and utensils, and other forms of close contact.

Teen at doctor's office, receiving a mono diagnosis

SDI Productions / Getty Images

What Is Mono?

Mono is a very common infectious disease. More than 90% of Americans are infected with it by age 35. It mainly affects teenagers and young adults, but children can also contract it. For most people, mono isn't very serious and will improve over time with proper treatments.

Symptoms can include:

  • Extreme fatigue
  • Body aches
  • Fever
  • Sore throat
  • Rash
  • Swollen lymph nodes in the armpits as well as the neck
  • Less commonly, swollen liver and enlarged spleen

These symptoms can disrupt your daily life, making it difficult to focus on school or work. Generally, people who contract mono recover in about two to four weeks. For some, the fatigue may last longer, up to six months after getting sick.

Is Mono Contagious?

Mono is very contagious. About 90% of mono cases are the result of EBV, which stays in its inactive form in your body even after you recover. Most likely, people will only develop mono once, but if EBV reactivates, it usually doesn't cause additional symptoms. That being said, you could potentially spread it to others, and people with compromised immune systems may develop symptoms more than once in their lifetime.

Beyond EBV, other viruses that cause mono include:

There is no vaccine for mono. Treatment revolves around doing what you can to alleviate and manage your symptoms. This means drinking lots of fluids, taking over-the-counter medications to relieve fever or pain, and getting lots of rest. You should also avoid contact sports that could potentially cause your spleen to rupture. Healthcare providers may also recommend that you avoid penicillin antibiotics, such as amoxicillin, if you have infectious mono.

To make a diagnosis, your medical provider will assess your symptoms and check for swollen lymph nodes in your neck. They can usually determine when someone has mono by symptoms alone. You may need blood tests if you don't have a typical case of mono.

How Is Mono Spread?

EBV is a kind of herpes virus. Keep in mind this is different from HSV, which causes oral and genital herpes, but both can be transmitted through sexual contact. Typically, EBV is spread through bodily fluids. This can mean genital secretions from sexual contact, blood, and saliva.

A common way of transmitting the virus is by sharing drinks or eating utensils. Condomless sex and kissing are easy ways to spread mono as well. You can also get mono through blood transfusions, organ transplants, or being in close proximity to another person who is sneezing or coughing.

How To Stop the Spread of Mono

The common recommendation to avoid or stop the spread of mono is simple. Avoid kissing, sharing drinks and utensils, and having sex without condoms with people who have mono or are showing symptoms of the illness. If you are experiencing any of the symptoms yourself, refrain from engaging in these activities until your symptoms have cleared.

Is Mono an STD?

A 2007 article in the The Journal of Infectious Diseases took a look at the history of our understanding of EBV. The authors found that it took awhile for EBV to be regarded as readily as other herpes viruses in the discussion of common sexually transmitted viruses.

"Of the 8 human herpes viruses, four can be sexually transmitted. These 4 viruses—HSV, CMV, KSHV, and EBV—present a spectrum of sexual transmissibility and pathogenic consequences and differ greatly in both respects," the paper authors write.

It's important to clarify that mono can be considered an STD, but not all cases are a result of sexual transmission. More regularly, it is transmitted through saliva. You are more likely to be at risk by sharing a glass of water or using common eating utensils with someone who has mono. If you find yourself experiencing any of the symptoms or think you may have been exposed, contact your physician or medical provider to assess your symptoms.

Beyond this, if you think you may be experiencing symptoms of mono, make sure you give your body plenty of rest and hydrate regularly.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Cleveland Clinic. Mononucleosis.

  2. Centers for Disease Control and Prevention. Epstein-Barr virus and infectious mononucleosis.

  3. Pagano JS. Is Epstein-Barr virus transmitted sexually? The Journal of Infectious Diseases. 2007;195(4):469-470. doi: 10.1086/510861

By Brian Mastroianni
Brian Mastroianni is a health and science journalist based in New York. His work has been published by The Atlantic, The Paris Review, CBS News, The TODAY Show, Barron's PENTA, Engadget and Healthline, among others.