EBNA-1 (Epstein-Barr nuclear antigen 1)

What is EBV?

Epstein-Barr virus (EBV) is generally responsible for causing mild to moderate illness. Blood tests for EBV identify antibodies to the virus within the bloodstream, aiding in the diagnosis of an EBV infection. The virus is very contagious and easily passed from person to person. It is present in the saliva of infected individuals and can be spread through close contact such as kissing and through sharing utensils or cups.

What are the symptoms of EBV infection?

EBV infection typically occurs during childhood and often presents with minimal or no symptoms. Nonetheless, when the initial infection takes place during adolescence, it can lead to infectious mononucleosis, commonly referred to as mono. Mono is characterized by symptoms like fatigue, fever, sore throat, swollen lymph nodes, an enlarged spleen, and occasionally an enlarged liver. These symptoms manifest in approximately 25% of infected teenagers and young adults and typically subside within a month or two.

What is the purpose of this test?

EBV antibody tests are used to ascertain whether the symptoms being experienced by individuals are a result of a current EBV virus infection or not. Testing serves the purpose of distinguishing a primary EBV infection, which has not been demonstrated to impact a developing fetus, from infections such as CMV, herpes simplex virus, or toxoplasmosis. These particular illnesses can potentially lead to pregnancy complications and pose risks to the unborn baby.

Throughout a primary EBV infection, the levels of these EBV antibodies undergo fluctuations at different stages of the infection. Analyzing these antibodies in the blood can assist in diagnosis and generally offers the healthcare provider insights into the infection's stage, indicating whether it is a current, recent, or past infection.

What are the recommended tests for a susceptible person to EBV?

The Centers for Disease Control and Prevention (CDC) recommend ordering several tests to help determine whether a person is susceptible to EBV or to detect a recent infection or a prior infection, or a reactivated EBV infection. These tests include:

• Viral capsid antigen (VCA)-IgM
• VCA-IgG
• D early antigen (EA-D)
• Epstein Barr nuclear antigen (EBNA)

When is Epstein-Barr Nuclear Antigen (EBNA) antibody typically detected in the blood?

EBNA typically doesn't appear until the acute infection has cleared, usually emerging approximately 2 to 4 months after the initial infection and persisting for a person's lifetime.

Is there any concern about reactivation of the virus?

Reactivation of the virus is generally not a health concern unless the individual experiences substantial and persistent immunocompromise, which can occur in individuals with conditions like HIV/AIDS or in organ transplant recipients. In such cases, primary infections can be more severe, and some individuals may encounter chronic EBV-related symptoms.