Epstein-Barr Virus (EBV) is a common human herpesvirus found globally. Over 90% of people will experience an EBV infection at some point in their lives. Once infected, the virus establishes a permanent presence within the body.
Acute Primary Infection
In young children, primary EBV infection is often asymptomatic or presents with mild, cold-like symptoms, making it hard to distinguish from other childhood illnesses. In adolescents and adults, the infection can manifest as infectious mononucleosis, commonly known as “mono” or “glandular fever.”
This condition typically involves profound fatigue, fever, a sore throat, and swollen lymph nodes. Other symptoms can include body aches, skin rashes, or an enlarged spleen or liver. The incubation period for symptomatic primary EBV infection averages four to six weeks.
Symptoms of mononucleosis usually resolve within two to four weeks, though fatigue may linger for several weeks or months. During this acute phase, the virus actively replicates and is highly contagious, primarily spreading through saliva.
Latent Infection
Following acute primary infection, EBV transitions into a latent state within the body. The virus remains present, primarily residing in B-lymphocytes, a type of white blood cell. Latency signifies the virus is largely inactive, not actively replicating or causing noticeable symptoms.
The virus persists in this dormant form for the remainder of an individual’s life. While generally not contagious during latency, the virus can occasionally be shed in oropharyngeal secretions, even without symptoms. This intermittent shedding means infected individuals can still transmit the virus, though typically at lower levels than during acute infection.
Reactivation
Despite remaining dormant, latent EBV can periodically reactivate. Reactivations are frequently asymptomatic, or may cause only mild, non-specific symptoms.
Common triggers for viral reactivation include periods of stress, other illnesses, or a weakened immune system. During these periods, the virus can be shed in saliva, making the individual contagious once more. This shedding can occur intermittently for weeks to months after initial infection, even after symptoms have resolved, allowing for continued transmission.
Chronic Active Epstein-Barr Virus Infection
Chronic Active Epstein-Barr Virus (CAEBV) infection is a rare and severe manifestation distinct from typical viral reactivation. Unlike most EBV infections, CAEBV involves persistent and debilitating symptoms lasting over six months. This condition is characterized by uncontrolled proliferation of EBV-infected T or NK cells.
Symptoms of CAEBV can include persistent high fever, severe chronic fatigue, enlarged lymph nodes, and liver dysfunction. Other severe complications may involve an enlarged spleen, anemia, and neurological issues. CAEBV requires specialized medical attention due to its severity and potential for life-threatening complications, such as organ failure or lymphoma.
Diagnosis and Management of EBV
Diagnosis of EBV infection typically involves blood tests that detect specific antibodies produced by the immune system in response to the virus. These antibody tests, such as Viral Capsid Antigen (VCA) IgM and IgG, and EBV Nuclear Antigen (EBNA) IgG, can indicate whether an infection is recent, past, or if the individual is susceptible. For instance, VCA IgM often suggests a recent or acute infection, while VCA IgG and EBNA IgG indicate a past infection.
For most EBV infections, including infectious mononucleosis, there is no specific antiviral treatment. Management primarily focuses on supportive care to alleviate symptoms. This includes plenty of rest, hydration, and over-the-counter medications like acetaminophen or ibuprofen for fever and pain relief. In severe or chronic cases, such as CAEBV, more specific medical interventions, including hematopoietic stem cell transplantation, might be considered, though these are rare and complex.