A common virus may be one contributing cause of multiple sclerosis

Enlarged particles of the common human Epstein-Barr Virus (EBV) shown in bright green, spiky blue, orange, and pink against a dark blue background

Discovering the cause of a disease is not easy. One reason is that the vast majority of diseases do not have a single cause. Instead, most diseases occur because multiple factors combine to cause the disease.

One factor is genes. Some people are born with one or more genes that make them vulnerable to a disease. Other factors come from your environment and behavior: what you eat, the air you breathe, the amount of physical activity you engage in, and habits such as smoking. Recent research finds that certain viruses may also be important contributing factors in causing multiple sclerosis (MS).

Multiple sclerosis harms cells in the brain and spinal cord — but why?

Multiple sclerosis is a disease of the brain and spinal cord that can cause many neurological symptoms, including arm and leg weakness, loss of vision, and difficulty thinking, as well as severe fatigue. Over the past 50 years we’ve learned that MS is an autoimmune disease: in various ways, the immune system attacks the brain and/or the spinal cord, leading to the symptoms of the illness.

However, we haven’t figured out why: what causes the immune system to go on the attack? Over the years, several viruses have been proposed as causes of MS, only to have subsequent research show that they were not. That led some MS doctors and scientists to discount viruses as possible causes.

Yet growing evidence in recent years points to several viruses that may be triggers of MS. The strongest evidence is for Epstein-Barr virus (EBV). This virus infects most people in developed nations like the US in their teen or young adult years.

Once a person is infected, the virus quietly remains alive in the body for the rest of a person’s life. In most people, it causes no health problems. But, rarely, it can cause certain cancers. Now, it has been linked to multiple sclerosis.

Delving deeper into a link between Epstein-Barr virus and MS

A large, long-term study from Harvard, published in the prestigious journal Science, attracted a lot of attention. Blood samples were repeatedly collected from 10 million US military personnel over 20 years. The samples were tested for evidence of infection with EBV.

Over the 20 years, some people in the study developed MS. The researchers compared two groups: people who were not infected with EBV when they entered military service, but then became infected later on; and people who remained uninfected by the virus. Those in the first group were 32 times more likely to develop MS than those in the second group. On average, symptoms of MS began about five years after a person became infected with EBV.

What do these findings tell us? The study provides strong evidence that a new infection with EBV is one important factor — maybe even a necessary factor — in causing MS. But the story is more complicated than that. Think about this: About 95% of all humans become permanently infected with EBV by early adulthood, but fewer than 1% of people develop MS. So, just being infected with EBV doesn’t mean a person will get MS — far from it. Indeed, other factors besides EBV infection also must be involved in causing MS.

Those other factors almost certainly include being born with certain genes that make you vulnerable to getting MS. Being infected with other viruses, as well as EBV, also may be important factors.

But which viruses? In my opinion, growing evidence indicates that a “cousin” of EBV, called human herpesvirus-6A, also may be important in triggering MS. And the genes of endogenous retroviruses also may be factors.

What are endogenous retroviruses?

About 8% of the genes that we are born with come from ancient viruses called retroviruses. These viral organisms successfully inserted their genes into the genes of the animals that preceded, and led to, humans. Some of those genes can be turned on to make proteins that affect our immune systems. Finally, there is evidence that each of these viruses — EBV, human herpesvirus-6A, and endogenous retroviruses — can activate one another, and gang up to cause a disease.

Going forward: New research may offer new leads for prevention

If the Epstein-Barr virus is one important factor in causing multiple sclerosis, then it is possible that vaccines against EBV might lead to fewer cases of MS. Indeed, several scientific groups around the world are working on such vaccines.

One company that made the mRNA vaccine for COVID-19 is working on an mRNA EBV vaccine. The National Institutes of Health also is developing a vaccine. However, it is unlikely we will know if they are effective against EBV, or against the development of MS, for at least a decade. Still, the linkage with this virus may prove to be an important milestone in ultimately conquering multiple sclerosis.

Long-lasting healthy changes: Doable and worthwhile

Graphic of the words "old habits" and "new habits" on torn blue paper

I’ve been a physician for 20 years now, and a strong proponent of lifestyle medicine for much of it. I know that it’s hard to make lasting, healthy lifestyle changes, even when people know what to do and have the means to do it. Yet many studies and my own clinical experience as a Lifestyle Medicine-certified physician have shown me a few approaches that can help make long-lasting healthy lifestyle changes happen.

What is lifestyle medicine?

In the US, lifestyle medicine is built around six pillars: eating healthy foods; exercising regularly; easing stress; getting restful sleep; quitting addictive substances like tobacco and limiting alcohol; and nurturing social connections.

How will this help you? Here’s one example. A study published this summer in the Journal Neurology followed over 70,000 health professionals for more than two decades. Those who reported eating a diet high in colorful fruits and vegetables had a significantly lower risk of subjective memory loss — which is a sign of dementia — compared with those who did not.

A multitude of studies over many years have mined health data on this same cohort. Harvard T.H. Chan School of Public Health nutrition expert Dr. Walter Willett observed that, based on these studies, four combined healthy lifestyle factors — a healthy diet, not smoking, engaging in moderate activity, and avoiding excess weight — could prevent about 70% to 80% of coronary heart disease and 90% of type 2 diabetes. The catch, he noted, is that only about 4% of people participating in these studies attained all four.

Abundant research shows healthy lifestyle factors protect us against serious, often disabling health problems: diabetes, high blood pressure, dementia, heart disease, strokes, cancer, and more. Clearly, taking steps toward a healthier lifestyle can make a big difference in our lives, but it can be hard to change our habits. Below are a few tips to help you start on that path.

Find motivation

What motivates you? Where will you find good reasons to change? Yes, studies show that being at a healthy weight and shape is associated with a longer life and lower risk of many chronic diseases. However, in my experience, only emphasizing weight or waist size isn’t helpful for long-term healthy lifestyle change. Indeed, studies have shown that focusing too much on those numbers is associated with quitting a health kick, whereas small goals related to positive actions were associated with successful long-term lifestyle change.

Examples of this include aiming for at least 21 minutes of activity per day and/or five servings of fruits and vegetables per day. (These activity and nutrition goals are actually recommendations of the American Heart Association, FYI!) If we strive to live healthy so that we can live a long, healthy life, we have a greater chance of long-term success — which typically will result in weight and waist loss.

Put healthy habits on automatic

Healthy choices can become more automatic if you remove the “choice” part. For example, take the thinking out of every eating or activity decision by planning ahead for the week to come:

  • Choose a basic menu for meals and build in convenience. Focus on simple, healthy recipes. Frozen produce is healthful, easy to keep on hand, and sometimes less expensive than fresh. Shopping the salad bar costs more, but could help on busy nights.
  • Jot down your activity schedule. Choose some physical activity most days — the more vigorous and the longer the better, but anything counts! Even as little as 10 minutes of light to moderate activity per week has been associated with a longer life span.
  • Track food and activity choices each day. Using an app or notebook for this can help you become more aware and accountable. Try noting barriers, too, and brainstorm workarounds for overly busy days and other issues that push you off track.

Understand how emotions affect you

If feeling stressed, angry, or sad is a trigger for overeating or another unhealthy activity, it’s important to recognize this. Writing down triggers over the course of a week can enhance your awareness. Building better stress management habits can help you stick to a healthy lifestyle plan. Getting sufficient restful sleep and scheduling personal time, regular activity, and possibly meditation, therapy, or even just chats with good friends are all steps in the right direction.

A healthy lifestyle is key to a long, healthy life, and is attainable. Success may require some thoughtful trial and error, but don’t give up! I have seen all kinds of patients at all ages make amazing changes, and you can, too.

Repeating the story: What to expect in the emergency department

Red and white sign outside a hospital with the word "Emergency" pointing toward the emergency department; it's nighttime and an ambulance is parked outside

Hospitals across the country are still scrambling to recover from the toll of an ever-shifting pandemic. What does that mean if you wind up in an emergency department (ED) due to an illness or accident? What should you know and what can you expect? As an emergency medicine doctor at a large teaching hospital, here are some key points to help you navigate a visit to the ED.

The starting line

In the chaos of an emergency department, odds are high that you will encounter a rotating crew of clinical and administrative staff. Their initial goal is to get each person registered for the visit, assess how urgently they need a clinician, and determine which treatment and diagnostic tests are needed. Usually, this is not a simple or quick process. Getting you the care you need hinges on first gathering the information you can provide, and then applying our skills and a range of tools to interpret it. Throughout this process you will be asked to repeat your story several times.

What brings you to the emergency room?

The opening question “What brings you to the emergency department?” is the portal of entry that allows emergency room clinicians to explore your ailment or concerns. The first time around, you’ll probably be eager to answer. The difficulty is the second, third, and fourth time the same question is asked. Yes, everyone is asking the same question, and you are telling the same story.

Good communication is key. We need correct, clear, and comprehensive information from you to guide your care in the emergency department. Seeking and getting accurate information reassures clinicians that informed and complete care is being delivered. Every discussion should welcome you into the conversation so that you may participate while clinicians make decisions.

Throughout your care, you should always be able to say, “Can you please explain what is happening?” or “Could you say that in a different way, because I’m not understanding you.” You can also ask “Is it possible to do this another way?” or “Can I take a break?” (In some instances, of course, that may not be possible.)

Who will you see?

Waiting in the emergency department is itself a journey, particularly at academic medical centers with deep health resources and personnel. At an academic ED like the one I work in, you might first speak with the triage nurse, who asks screening questions that will inform how quickly you need to be seen, then an assigned nurse, who might provide care for you for the entire visit, and later a resident or medical student.

The resident or student ultimately presents your case to me, an attending physician. Some EDs have physician assistants or nurse practitioners who work independently, or in collaboration with attendings. So you might see as many as five clinicians. Often when I ask people to repeat their story I hear, “I’m sorry, I’ve already told the story multiple times. Do we have to go through the process again?” I understand their preference to move the visit forward, not backward. But yes, I have them tell it again, even if it is a shorter version, hoping to glean details that help build a diagnosis.

Why will you wait?

There are many reasons for lengthy waits, which grew still longer at many EDs during the pandemic. First, uniting the team into one conversation is often difficult. Our patients arrive sporadically, procedures need to be performed, phone calls occur, family meetings arise, and so forth. Staggering the team is usually the most efficient way to function.

Teaching hospitals at academic medical centers train future doctors. By seeing you without supervision and discussing their medical decisions with experienced physicians like me, residents and students learn to form their own clinical judgment. Their independence during training helps keep our healthcare system afloat.

Equally important, spacing out interviews can help us find missed information to reach the correct diagnosis. In one case I vividly recall, a nurse initially thought a patient reporting pelvic pain had a urinary tract infection. Later, a junior resident and I asked clarifying questions, hoping to further uncover the root of her illness. We closely examined the location of pain and noticed extensive infection — a severe skin infection called necrotizing fasciitis. We immediately called the surgeons and radiology suite for an imaging scan to confirm the diagnosis and treat her as quickly as possible.

Why is teamwork so essential?

Often nurses, junior residents, or midlevel providers such as physician assistants catch details attending doctors miss during brief histories and physicals. No matter who identifies the diagnosis or orders the correct test, we work as a team. We gather information as a team and compare the data together. The benefit of repeating a history or exam is that gaps close and the best care becomes clear.

A part of the history that was previously skipped is covered. A part of the exam that wasn’t done can be performed. Perhaps you’ll remember enlightening details you had previously forgotten to tell us. Or, as time ticks by, initially mild abdominal pain that offered a hazy clue progresses during repeat exams to severe abdominal pain, and now an imaging study can help make a final diagnosis.

When you’re a patient, it’s hard to wait. It's hard to repeat your story. We know it; we’ve been patients, too. But the system, while not perfect, is built to protect you from the impact of missed information. And in some hospitals, the systems we rely on help train future clinicians — the highly skilled doctors, nurses, and specialized practitioners who will help care for you and many others throughout the years to come.