Infectious mononucleosis, or mono, is a disease spread throughsalivaand other bodily fluids. It is therefore also known as “the kissing disease.” Mono is common in settings where individuals are in close quarters, such as college dormitories. Although less common, mono can also be spread through sexual contact, blood transfusions, and organ transplants.
There is no vaccine to protect you against mono, and people can spread it before they know they have the illness. So, the best prevention is to avoid close contact with someone who may have the disease and to not share items like water bottles, toothbrushes, and eating utensils—anything that can spread saliva—with others.
When Is Mono Contagious?
People who have been infected with mono are contagious as soon as they become infected. They can remain contagious for several months.
It’s important to note that even people without symptoms can transmit the virus. They may not know that they have mono, but they can still pass it on to someone else. Even when mono symptoms do show up, they may take a while to appear, about one to two months. This time before symptoms is referred to as theincubation period.
People also are contagious while they have symptoms, which can last from two to four weeks or even longer. Health experts aren’t sure how long people with mono remain contagious after symptoms are gone, but it seems they can still spread the infection for months afterward.
Once you get mono, the virus remains in your body for life. It can resurface occasionally, and you can infect others during these times.
Can You Get Mono Twice?
Prevention Steps
Verywell / Michela Buttignol
Good handwashing practices are also important and can reduce your risk of infection if you are exposed to the virus.Make sure to use antibacterial soap and wash your hands for at least 20 seconds. If you usehand sanitizer, choose one with at least a 60% alcohol content.
How Common Is Mono?
When to See a Doctor
Typical symptoms of mono include:
Concerning symptoms or worsening symptoms that may warrant a call to your healthcare provider include those that last for more than 10 days and the following:
This is not an exhaustive list of symptoms. It’s best to call your healthcare provider if you are unsure if a symptom is problematic. Your healthcare provider will assess your symptoms and check for an enlarged spleen or liver. They may also order blood tests to check for antibodies to EBV and a high number of white blood cells, which is a sign of infection.
A rare but serious complication of mono is aruptured spleen, which can happen if your spleen becomes swollen. A ruptured spleen requires immediate medical attention. It is wise to avoid vigorous contact sports while you are infected with mono.
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A Word From Verywell
It’s difficult to identify who has been infected with mono, especially when the affected individual doesn’t show symptoms. Therefore, it can be difficult to prevent mono because the best way to do that is to avoid close contact with someone who has it.
Still, it’s good to stay healthy and practice good hygiene, including not sharing personal items, to minimize your chances of getting infected. If you do become sick with mono, you will be able to recover with plenty of rest and fluids. If you experience any unusual symptoms, contact your healthcare provider right away and find out whether mono or something else is causing your symptoms.
4 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Ginsburg CM, Henle G, Henle W.An outbreak of infectious mononucleosis among the personnel of an outpatient clinic.Am J Epidemiol. 1976;104(5):571-575. doi:10.1093/oxfordjournals.aje.a112332Kids Health.How long is mono contagious?The Boston Public Health Commission.Mononucleosis.Cleveland Clinic.Mononucleosis.
4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Ginsburg CM, Henle G, Henle W.An outbreak of infectious mononucleosis among the personnel of an outpatient clinic.Am J Epidemiol. 1976;104(5):571-575. doi:10.1093/oxfordjournals.aje.a112332Kids Health.How long is mono contagious?The Boston Public Health Commission.Mononucleosis.Cleveland Clinic.Mononucleosis.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Ginsburg CM, Henle G, Henle W.An outbreak of infectious mononucleosis among the personnel of an outpatient clinic.Am J Epidemiol. 1976;104(5):571-575. doi:10.1093/oxfordjournals.aje.a112332Kids Health.How long is mono contagious?The Boston Public Health Commission.Mononucleosis.Cleveland Clinic.Mononucleosis.
Ginsburg CM, Henle G, Henle W.An outbreak of infectious mononucleosis among the personnel of an outpatient clinic.Am J Epidemiol. 1976;104(5):571-575. doi:10.1093/oxfordjournals.aje.a112332
Kids Health.How long is mono contagious?
The Boston Public Health Commission.Mononucleosis.
Cleveland Clinic.Mononucleosis.
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