Epstein-Barr virus (EBV) infection is a viral infectious disease of humans that occurs in subclinical or clinical forms with local or multiple organ lesions. The virus replicates in upper (...)
Epstein-Barr virus (EBV) infection is a viral infectious disease of humans that occurs in subclinical or clinical forms with local or multiple organ lesions. The virus replicates in upper respiratory tract, epithelium of digestive tract and associated lymphoid tissue. EBV induces the appearance of a population of reactive T-cells and polyclonal activation of B-cells and their differentiation into plasma cells that produce low-affinity antibodies to the virus. EBV is the etiological agent of diseases such as infectious mononucleosis, Burkitt’s lymphoma and nasopharyngeal carcinoma.
Epstein-Barr virus is a widespread virus. The most people are infected in childhood, and in the age of three years 30-80% of people are carriers of EBV. In developed countries, 85% of the adult population are seropositive for EBV.
PCR and serological methods of research are used for laboratory diagnosis of EBV infection. The latter include tests for detection of heterophile antibodies and identification of specific antibodies by enzyme-linked immunosorbent assay (ELISA). The latter method makes possible not only to establish the fact of infection with EBV but also to determine the stage of disease.
The optimal combination of serological tests for diagnosis of EBV infection includes detection of IgG and IgM antibodies to viral capsid antigen (anti-VCA-IgG, anti-VCA-IgM) and nuclear antigen (anti-EBNA-IgG). Anti-VCA-IgM antibodies appear during early infection and disappear within 4-12 weeks. Anti-VCA IgG appear later, initially increase to a high level in the early stages of the disease and then gradually decrease remaining detectable throughout the life. If antibodies to viral capsid antigen are not detected a person is susceptible to EBV infection.
Antibodies to early antigen (anti-EA-IgG) are detectable only during acute infection and disappear in the vast majority of patients after 3-6 months. However, in 20-30% of healthy people anti-EA IgG antibodies are detected lifelong, making this diagnostic marker less informative.
Anti-EBNA-IgG is produced 1-6 months after the infection and remaining in the majority infected people throughout the life. Simultaneous detection of specific IgG to EBNA and VCA is an indicator of past-infection.