Abnormal Response to Epstein-Barr Virus Found in Schizophrenia Patients

According to a new study from Johns Hopkins Medicine and Sheppard Pratt Health Systems participants with schizophrenia were found to have elevations in their level of antibodies against the Epstein-Barr Virus (EBV). EBV is a herpes virus that causes infectious mononucleosis, aka mono. It initially causes fever and swollen lymph nodes and is commonly transmitted through oral contact such as kissing, hence it’s moniker as “the kissing disease”.

Researchers found that those with Schizophrenia had increased level of reactivity to EBV-viral capsid antibody, whereas they did not have increased reactivity to EBV-nuclear antigen. Researchers concluded that due to patient’s with schizophrenia increased levels of antibodies to only some EBV proteins there is indication for an aberrant response to EBV infection. This aberrant response to EBV infection is believed to contribute to schizophrenia altering patients’ immune systems making them more susceptible to EBV overall. Another explanation for the heightened immune response is that EBV infection could potentially increase the risk of schizophrenia.

The original article was published online Nov. 20^th in .

According to the Theodore and Vada Stanley Distinguished Professor of Neurovirology in Pediatrics at John’s Hopkins Children’s Center and senior author of the study, researchers “found that individuals with schizophrenia had an unusual response to Epstein-Barr virus. This indicated that the prevention and treatment of Epstein-Barr virus might represent an approach for the prevention and treatment of serious psychiatric disorders such as schizophrenia." However, he cautioned that the study wasn’t designed to determine cause and effect.

Researchers conducted the study by measuring immunoglobulin G (IgG) class antibodies to EBV virions defining proteins in 432 individuals with schizophrenia and 311 individuals without any history of psychiatric disorder. By looking at the odds of having these antibodies in the 50^th, 75^th, and 90^th percentiles they found people with schizophrenia were 1.7 to 2.3 times more likely to have increased levels of some EBV antibodies compared with individuals without schizophrenia. Researchers also measured antibodies to other related viruses, like chicken pox and herpes simplex type 1/cold sore virus and did not find an increase of antibodies against these viruses in individuals with schizophrenia. Suggesting that only EBV was associated with increased risk of schizophrenia.

“We are interested in the role of infectious agents such as Epstein-Barr virus in schizophrenia and other serious psychiatric disorders, so we did this study to look at the associations,” said Yolken. Leading researchers to also sequence a portion of participant’s DNA to determine their genetic risk for schizophrenia. The results of the analysis showed that individuals with both evidence of increased genetic risk for schizophrenia and increased antibody levels to EBV had a higher chance, eight times higher, of being in the schizophrenia group compared to the control group.

As of now, there are no FDA approved treatments for EBV, but compounds that may prevent or treat replication of EBV are under investigation. Researchers consider the development of these compounds, and a possible treatment, to be high priority in order to help individuals with schizophrenia and other disorders associated with susceptibility of EBV. For now, researchers are recommending preventing EBV transmission through hygienic practices like hand washing and avoiding oral contact, such as kissing, with infected individuals.