Individuals With Schizophrenia Exhibit 'Unusual Response' to Epstein-Barr Virus

The link between infectious disease agents and psychiatric disorders has long been debated, and now new research out of Johns Hopkins Medicine and Sheppard Pratt Health System has identified a connection between schizophrenia and Epstein-Barr virus.

Investigators employed solid phase immunoassay techniques to measure immunoglobulin G class antibodies to Epstein-Barr virus virions and focused in on the proteins in 423 individuals with schizophrenia and 311 without a psychiatric disorder.

The results of their investigation, published recently in Schizophrenia Bulletin, indicate that individuals with schizophrenia had an abnormal immune response to the herpesvirus that causes mononucleosis, specifically a “marked elevation” in the level of Epstein-Barr virus antibodies compared with the control group, which did not have a history of a psychiatric disorder.

Interestingly, people with schizophrenia did not exhibit the heightened immune response to all of the Epstein-Barr virus proteins.

“[The investigators] measured the antibodies to other related viruses such as varicella/chicken pox or herpes simplex type 1/cold sore virus, and didn’t find an increase of antibodies against these viruses in people with schizophrenia,” a Johns Hopkins statement reported. “These findings suggest that only Epstein-Barr virus was associated with increased risk of schizophrenia.”

The team of investigators, led by Robert Yolken, MD, the Theodore and Vada Stanley Distinguished Professor of Neurovirology in pediatrics at Johns Hopkins Children’s Center, also sequenced portions of the study participants’ DNA to determine the genetic predisposition to developing schizophrenia.

Those who possessed genetic markers of schizophrenia in addition to the increased immune response to the Epstein-Barr virus proteins were 8 times more likely to be in the schizophrenic study group, investigators found.

While this particular study doesn’t necessarily answer the “chicken or the egg” question of causation, Dr. Yolken said the research is beneficial to physicians and clinicians.

“In terms of health care providers, we should do what we can to prevent exposure to Epstein-Barr virus in younger children, which can be as simple as hand-washing,” Dr. Yolken told Contagion^® in an interview. “In the long run, we should do more to prevent Epstein-Barr virus and work toward a vaccine in the future.”

There’s also a big takeaway here for psychiatrists in the treatment of patients with psychiatric disorders, Dr. Yolken said.

“In patients with schizophrenia, they should avoid doing things that suppress their immune system, which can in turn trigger the Epstein-Barr virus,” he told Contagion^®, adding that eating a balanced diet and getting a seasonal flu shot are musts. “For psychiatrists focused on schizophrenia, it’s a good idea for them to focus on physical health [of the patient] as well and trying to minimize exposure to things that will suppress the immune system and allow viruses to reactivate, such as smoking [for example].”