Epstein–Barr Virus

Epstein–Barr Virus

Why in News? 

Recently, scientists have made progress toward developing an Epstein–Barr virus (EBV) vaccine by identifying key viral glycoproteins that trigger strong immune responses.

What is Epstein–Barr Virus (EBV)?

• About: Epstein–Barr Virus (EBV) is a highly contagious double-stranded DNA virus belonging to the Herpesviridae family (Human Herpesvirus-4). 

• • Transmission: EBV spreads mainly through saliva, which is why it is often called the “kissing disease”. It can also be transmitted via sharing utensils, blood transfusion, and organ transplantation. 
  • Symptoms: Common symptoms include fever, sore throat, swollen lymph nodes, fatigue, headache and enlarged spleen.
    • Many children remain asymptomatic, while adolescents and adults often develop infectious mononucleosis, characterized by prolonged weakness lasting weeks.
  • Impact: It primarily infects B-lymphocytes (immune cells) and epithelial cells. After initial infection, the virus remains dormant (latent) inside the body and may reactivate under conditions such as immune suppression or stress.
    • It is associated with multiple diseases such as infectious mononucleosis, Hodgkin lymphoma, Burkitt lymphoma, nasopharyngeal carcinoma and gastric cancer.  

• Regions: EBV-related cancers show higher prevalence in regions like East Asia and Sub-Saharan Africa, reflecting environmental and genetic risk factors.

• Severity: It is estimated to contribute to nearly 1.5% of all global cancer cases annually.
  • It is one of the most common human viruses globally, infecting nearly 90–95% of the adult population worldwide during their lifetime and establishing lifelong latent infection.
  • EBV is also linked with autoimmune diseases such as multiple sclerosis (MS), increasing long-term health risks.
• Treatment: There is currently no specific antiviral cure for EBV infection. Treatment focuses on symptomatic relief through rest, hydration, pain relievers and anti-inflammatory medicines. Severe complications may require hospitalization or corticosteroid therapy.

Global Cancer Burden Attributable to Epstein–Barr Virus (EBV)

• Viral Oncoproteins and Latency: EBV drives cancer through Latent Membrane Proteins (LMP1 and LMP2). LMP1 acts as a constitutional mimic of the CD40 receptor, activating pro-survival pathways like NF-κB, while LMP2A prevents B-cell apoptosis, allowing pre-cancerous cells to survive indefinitely.
• Nasopharyngeal Carcinoma (NPC): In endemic regions, EBV is present in over 98% of NPC cases. Recent 2025 data confirms that high plasma EBV DNA levels are not only diagnostic but also predict a 4.5-fold increase in recurrence risk following radiotherapy.
• Gastric Cancer Subtype: EBV-associated gastric cancer (EBVaGC) represents nearly 9% of stomach cancers. It is characterized by extreme DNA hypermethylation and PIK3CA mutations, making these tumors particularly responsive to newer immune checkpoint inhibitors like PD-1 blockers.
• Burkitt Lymphoma Pathogenesis: In equatorial Africa, Endemic Burkitt Lymphoma is nearly 100% linked to EBV. The virus cooperates with c-MYC translocation, accelerating B-cell proliferation. Statistics show children with high viral loads are at significantly higher risk.
• Hodgkin Lymphoma Connection: EBV is found in the “Reed-Sternberg” cells of approximately 40% of Hodgkin Lymphoma cases in the West. Studies indicate that patients with EBV-positive HL often have a distinct clinical profile, frequently requiring targeted T-cell therapies.
• Multiple Sclerosis and Lymphoma Risk: Newer longitudinal studies confirm that the neuro-inflammatory damage in MS, caused by EBV, correlates with a slightly elevated risk of CNS lymphomas. The virus acts as a persistent trigger for chronic B-cell activation.
• Immune Evasion and Metastasis: EBV secretes viral microRNAs (BHRF1) that silence the host’s tumor-suppressor genes. This molecular “cloaking” allows infected cells to evade NK cells, increasing the probability of distant metastasis in epithelial malignancies.

Recent Scientific Breakthroughs in EBV Vaccine Development

• First-Ever mRNA-Based EBV Vaccines: A major breakthrough is the development of mRNA-based vaccines such as mRNA-1189, which target Epstein–Barr Virus (EBV) entry proteins. These vaccines encode viral glycoproteins essential for infection, enabling the immune system to recognize and neutralize EBV before it infects B-cells and epithelial cells.
  • In March 2024, randomized trials showed that mRNA-1189 was immunogenic and well-tolerated across all dose levels in adults aged 18–30 years, indicating early safety and the ability to generate strong neutralizing antibody responses against EBV infection.
  • Following Phase-1 success, a Phase-2 dose-finding trial for mRNA-1189 has been fully enrolled by 2025, focusing on optimizing dosage levels to prevent Infectious Mononucleosis (IM)—the most common clinical manifestation of EBV globally.
  • In November 2025, trial data confirmed that mRNA-1195 generated strong immune responses and remained safe across all dose groups, marking progress toward preventing EBV-associated autoimmune diseases like MS.
• Multi-Antigen Vaccine Strategy: Unlike earlier single-protein vaccines, modern candidates encode multiple EBV proteins like gp350, gH/gL, gp42, and gB. These are critical for viral entry pathways, thereby improving immune response diversity and potentially blocking both latent infection and viral reactivation in humans. 
  • Parallel research is exploring ferritin nanoparticle-based gp350 vaccines, which display up to 24 antigen copies, producing high levels of neutralizing antibodies in animal models and protecting against EBV-like viral challenges. 
  • Recent research published in Cell Reports Medicine shows scientists are targeting key Epstein–Barr Virus (EBV) surface glycoproteins such as gp350 and gp42 to block viral entry into human immune cells. gp350 helps EBV attach to B-cell receptors, while gp42 facilitates membrane fusion.