What Are the Stages of Mono? How Long Do They Last?

The acute stage can last two to six weeks, but recovery can take months

There are three stages of mono (mononucleosis):

  • Prodrome stage, when symptoms start
  • Acute stage, when you feel the worst
  • Convalescent stage, when you begin to recover

These begin after a period of incubation, in which mono is in your system, but there are no obvious signs of it yet.

Some people may have symptoms for only two to six weeks. Others may have lingering effects—especially fatigue—until the virus that causes the illness becomes inactive, which can take months.

This article walks you through the stages of mono so you can get a better sense of what to expect and how to get over mono faster. It also looks at possible complications and ways to prevent getting mono and passing the virus to others.

Stages of Mononucleosis - Illustration by Danie Drankwalter

Verywell / Danie Drankwalter

Mono Incubation Period

The Epstein-Barr virus (EBV) is the most common cause of mono. It can take around four to six weeks for symptoms of mononucleosis to appear after you have been infected.

The period of time between exposure and the start of symptoms is called the incubation period.

Though may feel OK during this time, it's still possible for you to pass the virus on to others.

Mono Stage 1: Prodrome

The first stage of mono is called the prodrome stage. It ususally lasts three to five days.

Mono symptoms start to appear during this phase. These can include:

  • Fatigue or low energy
  • Feeling "off" or uncomfortable
  • Not feeling hungry
  • Sore throat

You can also have mono without symptoms. In particular, kids under the age of 10 may have very mild symptoms or none at all.

Mono Stage 2: Acute Phase

The second phase of mono is called the acute stage. During this time, a person's symptoms may start to get worse. Acute symptoms are often referred to as "classic" symptoms.

By and large, the acute symptoms of mono last for two to six weeks but may persist longer in some people.

Not everyone will experience every symptom of mono. Keep in mind that mono symptoms can also show up at different times over the course of the infection.

Mono Stage 3: Convalescent Phase

The last phase of mono is the convalescent stage. This is when you recover from the infection, which can take anywhere from three to six months.

By this stage, most mono symptoms have gotten better. However, some people still feel weak and tired.

If you have an inflamed or enlarged spleen during the convalescent stage, you will need to avoid any physical activity that could lead to spleen rupture.

How Long Is Mono Contagious?

Even after symptoms have cleared, the virus can be passed in saliva for up to 18 months.

Mono Treatment

There's no cure or specific treatment for mono. It can take a long time to get over the infection, and there's not much you can do to make the process go faster.

Supporting your body as it heals and fights off the virus is the best approach.

You can do this by:

  • Resting and getting plenty of fluids
  • Using over-the-counter (OTC) or prescription medications for pain and fever (Ask your provider before you use acetaminophen, as this medication can increase the risk of liver damage.)
  • Taking medications for inflammation, if needed

Providers may prescribe a corticosteroid if you have a severe case of mono.

Do I Need to Isolate If I Have Mono?

Mono can be passed to others, but you don't necessarily need to isolate when you are infected—if you follow certain precautions.

The mono virus is mostly spread through your spit (saliva). Mono can also spread if you cough or sneeze close to somebody.

When you are around others:

  • Avoid sharing eating and drinking utensils.
  • Refrain from kissing.
  • Do not share personal items, like lip balms.
  • Cover your coughs and sneezes using the inside of your elbow.
  • Wash your hands frequently.

Complications of Mono

People with severe mono can experience liver and spleen damage. There are also some other potentially serious complications of mono, such as:

The effects of these complications may persist even after you've recovered from mono itself.

Studies have shown that the Epstein-Barr virus might be linked to certain types of cancer, including Burkitt’s lymphoma and Hodgkin lymphoma.

Mono has also been associated with an increased risk of developing autoimmune diseases like multiple sclerosis.

Rarely, people with mono can develop a chronic active Epstein-Barr virus (CAEBV) infection. This can occur in people with a first-time infection or in people who have already recovered from the illness if the virus reactivates within the body.


Mono is a contagious illness that is usually caused by the Epstein-Barr virus. Mono has three stages: prodrome (when symptoms start), acute stage (when symptoms worsen), and convalescent (recovery).

Mono has a long incubation period, so it can be difficult to pinpoint when the illness actually started. On average, the prodrome phase lasts three to five days, the acute phase can last up to six weeks, and the final recovery stage can go on for up to six months.

Frequently Asked Questions

  • Does mono ever go away completely?

    Once you get mono, the virus will always stay in your body. However, it will not always be active. That means you won't always be sick and you won't always be able to spread the virus to other people.

  • What causes mono?

    Mono is most often caused by the Epstein-Barr virus, but about 10% of cases are due to other viruses. While having the virus that causes mono is very common, only a small number of people actually get mono.

10 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. Becker JA, Smith JA. Return to play after infectious mononucleosis. Sports Health. 2014;6(3):232-238. doi:10.1177/1941738114521984

  2. Stock I. Infectious mononucleosis--a “childhood disease” of great medical concern. Med Monatsschr Pharm. 2013;36(10):364-368.

  3. Saljoughian M. Diagnosing and treating mononucleosis. US Pharm. 2017;42(5):HS-7-HS-10.

  4. Balfour HH, Dunmire SK, Hogquist KA. Infectious mononucleosisClin Trans Immunol. 2015;4(2):e33. doi:10.1038/cti.2015.1

  5. Johns Hopkins Medicine. Infectious mononucleosis.

  6. Zhang L, Zhou P, Meng Z, et al. Infectious mononucleosis and hepatic function. Exp Ther Med. 2018;15(3):2901-2909. doi:10.3892/etm.2018.5736

  7. Herold J, Grimaldo F. Epstein-Barr virus-induced jaundice. Clin Pract Cases Emerg Med. 2020;4(1):69-71. doi:10.5811/cpcem.2019.10.45049

  8. Kimura H, Cohen JI. Chronic active Epstein-Barr virus disease. Front Immunol. 2017;8:1867. doi:10.3389/fimmu.2017.01867

  9. Nemours. How long Is mono contagious?.

  10. Dunmire SK, Hogquist KA, Balfour HH. Infectious MononucleosisCurr Top Microbiol Immunol. 2015;390(Pt 1):211-240. doi:10.1007/978-3-319-22822-8_9

By Angelica Bottaro
Angelica Bottaro is a professional freelance writer with over 5 years of experience. She has been educated in both psychology and journalism, and her dual education has given her the research and writing skills needed to deliver sound and engaging content in the health space.