Health risk calls for rapid vaccine development
Anew school term is well underway. Thousands of eager students are crammed in classrooms and lecture theatres in the yearly ritual of absorbing knowledge and exchanging ideas. And viruses.
Sneezes, chewed-on pencil ends, handshakes, hand-clapping games, sticker exchanges are all childhood rites of passage, shrewdly exploited by microorganisms in a yearly mass-deployment ritual. By now you might be thinking that we’re talking about the flu. But our miscreant is much more insidious — the EpsteinBarr virus.
Remember that childhood ear infection that was never fully explained, or that case of infectious mononucleosis that lasted for weeks? Turns out that may not be the last trouble EBV causes you. Once you contract this virus, like all members of the herpes virus family, you are infected for life. And almost everyone contracts the EBV before the age of 40. Most people get the virus in their childhood but don’t realize it because the infection is often asymptomatic.
Why does this matter? For roughly one in 20 people, that initial infection will lead to autoimmunity or cancer later in life. Abundant scientific evidence points to EBV as a cause of lupus, rheumatoid arthritis and multiple sclerosis. Hodgkin’s lymphoma, some gastric cancers and nasopharyngeal cancer are associated with EBV, as are a number of other autoimmune diseases and cancers.
A few months ago, a study in the journal Nature Genetics showed a categoric relationship between proteins produced by EBV and genes associated with autoimmunity.
Given the high cumulative societal cost of these diseases, the case for rapid vaccine development against EBV seems obvious. But that isn’t the case.
The good news is that vaccine development for EBV is in its advanced stages. It was shown in a Phase 2 human trial reported in 2004 that vaccination safely prevented infectious mononucleosis. Those vaccinated could still contract the virus, but no one got sick. The vaccine is analogous to shingles vaccines in this regard; those vaccines do not get rid of your chickenpox infection, they keep you from getting shingles.
Is the tested EBV vaccine good enough to prevent all autoimmunity and the EBV-related cancers? Because these diseases tend not to emerge for decades after EBV infection, that is not known with certainty. But we know that mono, rather than asymptomatic EBV infection, is a risk factor for developing Hodgkin’s lymphoma and MS. So, even if the vaccine does not prevent all autoimmunity and EBV-related cancers, a prevention for MS and EBV-related Hodgkin’s lymphoma would be monumental. After all, Canada has the highest rate of MS in the world and, like Hodgkin’s lymphoma, it often strikes during the prime of life.
What is needed is the completion of appropriate Phase 3 trials to ensure the vaccine is as safe and effective as it appears. These would cost tens of millions of dollars and regulatory approval would be required.
However, the issue is that the rate of progress is inconsistent with the public health emergency that EBV poses.
When Ebola received international attention, a vaccine was taken from animal studies to human Phase 3 trials and use in an emergency in about a year. Developments for some other viruses such as influenza and Zika face delays related to fundamental gaps in scientific understanding. Such gaps take painfully long to fill, but there appear to be no quick fixes available. For EBV, the fundamental gaps have already been filled since 2004.
The commitment of the global community is needed to provide the resources necessary to develop a safe and effective EBV vaccine licensed for use.
If a virus that kills or significantly disables nearly five per cent of the people on the planet isn’t an emergency, we are not sure what is. Immediate action on Phase 3 should be taken, perhaps organized by the World Health Organization, as was done with Ebola.