Infectious mononucleosis
An infection usually caused by the Epstein–Barr virus.
Infectious mononucleosis, often called mono or glandular fever, is typically caused by the Epstein–Barr virus (EBV), a member of the herpesvirus family. While EBV is responsible for about 90% of cases, a few other viruses can also trigger the illness. The virus is most commonly spread through saliva—earning mono the nickname "the kissing disease"—but it can rarely be transmitted via semen or blood. Sharing items like drinking glasses or toothbrushes, or exposure to a cough or sneeze, may also spread it. Infected individuals can pass the virus on weeks before symptoms appear.
Symptoms vary significantly by age. In children, the infection often causes few or no symptoms, or only mild flu-like signs similar to a common throat infection. For adolescents and young adults, the classic trio of symptoms emerges: fever (usually lasting about two weeks), a sore throat (severe for a few days, then resolving over a week or more), and swollen, movable glands, especially around the back of the neck. Fatigue is a major complaint, and headaches, abdominal pain, or nausea may occur. Most people recover within two to four weeks, but fatigue can linger for months—lasting over a month in roughly 28% of cases. A sore throat with pus on the tonsils is common, and about half of those affected develop small reddish-purple spots on the roof of the mouth. A rash may appear spontaneously, and nearly everyone given amoxicillin or ampicillin will develop a generalized, itchy rash (which does not indicate a future penicillin allergy). In older adults, the illness is less typical, often featuring prolonged fever, fatigue, and body aches rather than a sore throat; they are also more prone to liver enlargement and jaundice.
Complications are uncommon but include spleen enlargement (typically in the second and third weeks) and, in less than 1% of cases, splenic rupture. The liver may also enlarge, and jaundice or hepatitis occurs occasionally. In otherwise healthy people, mono generally resolves on its own. When caused by EBV, it is classified as an Epstein–Barr virus–associated lymphoproliferative disease, and in rare instances, it can persist as a chronic infection or develop into systemic EBV-positive T cell lymphoma.
The incubation period is estimated at 33 to 49 days, with symptoms in young adults appearing about four to six weeks after infection
- caused_by
- Epstein–Barr virus (EBV), human herpesvirus 4
- other_causes
- Cytomegalovirus, adenovirus, rubella, herpes simplex
- age_group_most_affected
- 15–24 years in developed world
- incubation_period
- 33–49 days (estimated); 4–6 weeks in adolescents and young adults
- recovery_time
- 2–4 weeks; fatigue may last months
- annual_US_incidence
- 45 per 100,000 people
- population_exposure_by_adulthood
- Nearly 95%
Quick Facts
- Field
- Infectious disease
- Symptoms
- Fever, sore throat, enlarged lymph nodes in the neck, fatigue
- Complications
- Swelling of the liver or spleen
- Duration
- 2–4 weeks
- Causes
- Epstein–Barr virus (EBV) usually spread via saliva
- Diagnosis
- Based on symptoms and blood tests
- Treatment
- Drinking enough fluids, getting sufficient rest, pain medications such as paracetamol (acetaminophen) and ibuprofen
- Frequency
- 45 per 100,000 per year (U.S.)
Facts from the source article.
Lore & Background
Infectious mononucleosis was first described in the 1920s. The disease is caused primarily by the Epstein–Barr virus, a member of the herpesvirus family. It is spread through saliva, and rarely through semen or blood. Objects such as drinking glasses or toothbrushes, or a cough or sneeze, can transmit the virus. Those infected can spread the disease weeks before symptoms develop. The incubation period is estimated at 33–49 days, with symptoms appearing around 4–6 weeks after infection in adolescents and young adults. Onset is often gradual, preceded by fatigue, feeling unwell, and body aches.
Reader's Guide
Infectious mononucleosis is significant as a common viral illness that primarily affects adolescents and young adults in the developed world, causing a characteristic triad of fever, sore throat, and swollen lymph nodes. In the developing world, infection typically occurs in early childhood with fewer symptoms. The disease is usually self-limiting, with most people recovering in two to four weeks, though fatigue may persist for months. Complications are rare but include splenic rupture in less than one percent of cases. Diagnosis is based on symptoms and confirmed with blood tests for specific antibodies; the monospot test is not recommended due to poor accuracy. There is no vaccine for EBV, though research is ongoing. Prevention involves avoiding shared personal items or saliva with an infected person. Treatment is supportive, including rest, fluids, and pain medications such as paracetamol and ibuprofen. The disease occurs equally at all times of the year.
Did You Know?
- Nearly 95% of people have had an EBV infection by the time they are adults.
- In less than one percent of cases, splenic rupture may occur.
- The monospot test is not recommended for general use due to poor accuracy.
- About 45 out of 100,000 people develop infectious mono each year in the United States.
Frequently Asked Questions
Who is Infectious mononucleosis?
Infectious mononucleosis, popularly nicknamed mono or glandular fever, is an acute viral illness most often triggered by the Epstein–Barr virus (human herpesvirus 4). A smaller share of cases is caused by other agents such as cytomegalovirus, adenovirus, rubella, or herpes simplex.
What are Infectious mononucleosis's powers/role?
The infection typically unleashes a combination of prolonged fatigue, sore throat, swollen lymph nodes, and fever after an incubation window of roughly four to six weeks in teenagers and young adults. In some patients, extreme tiredness can drag on for months even after the acute phase has resolved.
How does Infectious mononucleosis's story end?
Most individuals feel substantially better within two to four weeks, though residual exhaustion may linger for several additional months. The virus itself is never fully expelled; it settles into a lifelong latent state inside immune cells without usually provoking repeated symptomatic episodes.
Why is Infectious mononucleosis important?
It disproportionately strikes the 15-to-24 age bracket in developed nations and accounts for roughly 45 new cases per 100,000 people each year in the United States. Because carriers can shed the virus weeks before any symptoms appear, it remains a notable public-health concern in schools, dorms, and workplaces.
How does Infectious mononucleosis spread?
The virus travels primarily through saliva—earning the condition its famous 'kissing disease' moniker—though rarer routes include semen, blood, or shared items like drinking glasses and toothbrushes. Coughs and sneezes can also carry the pathogen, and an infected person may be contagious well before feeling unwell.
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