One could easily say that shingles—the painful, blistering reemergence of the virus that gave you chicken pox when you were a kid—is itself a very stressful situation. And, to make matters trickier, it’s possible that some particularly anxiety-producing experience preceded the outbreak, triggering the rash in the first place. What have researchers learned about the stress-shingles connection, and what do physicians who treat it have to say on the subject? Relax as much as you can—and read on.
Does Stress Literally Cause Shingles?
The quick but incomplete answer is “no.” Shingles (officially termed herpes zoster, or HZ) is caused by a virus—the varicella zoster virus (VZV)—that, before a vaccine became widely available in 1995, caused chicken pox mainly in children up to 12 years of age. At the conclusion of the disease phase of chicken pox, VZV retreats to the central nervous system (CNS), and like a hibernating bear in a cave, goes dormant. The problem is that decades later, the virus can wake up and reemerge along nerve pathways, erupting in painful, itchy blisters and, for some, complications including herpes zoster opthalmicus (which affects the eye and can create blindness) and postherpetic neuralgia (PHN), which is potentially debilitating pain along the same pathways that can last for months, and sometimes years, after the rash retreats. About 1 million Americans develop shingles every year, according to the Centers for Disease Control (CDC), or 1 in 3 adults over 50, when risk begins to climb dramatically.
The reason the virus becomes empowered to charge back with such a vengeance later in life has to do with a decline in the body’s immune response to bacteria, viruses, and fungi that naturally lowers with age. This weakened defense is where experts see a potential relationship between the body’s response to stress—of all kinds, physical and emotional—and how our inner chemistry can affect the immune function from keeping VZV at bay.
Stress, Cortisol, and Your Immune System
“How stress can impact an immune system is complex,” says Marla Shapiro, C.M., M.D., a professor in family and community medicine at the University of Toronto. “The science tells us that stress impacts our hormones, which in turn have an impact on our ability to mount defense responses. With stress our physiologic guard is down, so to speak,” she says.
The hormone at work here, Dr. Shapiro points out, is cortisol. A surge in cortisol in response to stress—the ancient adaptation often referred to as the “fight-or-flight mechanism”—actually boosts immunity by reducing inflammation if the stimulus is brief—akin to a saber tooth tiger, say, attacking a prehistoric cave dweller. But life isn’t prehistoric anymore, and modern stressors can be unrelenting, such as job loss or toxic workplaces, relationship reversals like divorce, health crises, the death of a loved one, poverty, discrimination, and even unprecedented shocks like a global pandemic.
What this means is our cortisol levels surge far more often, and they stay higher for longer. And that’s where our body’s immunity powers get tripped up. Sustained higher levels of cortisol end up increasing inflammation over time, as well as suppressing lymphocytes, those white blood cells that fight off infections. The lower your lymphocyte levels, the more at risk you are for viruses, including the common cold, cold sores, and a nasty virus hibernating in your central nervous system—VZV.
“VZV sleeps in the dorsal root ganglion for years and years and years,” says Jenny Murase, M.D., an assistant clinical professor of dermatology at the University of California, San Francisco, and director of Medical Dermatology Consultative Services for the Palo Alto Foundation Medical Group. (By the way, the dorsal root ganglion is collection of sensory neurons near the spine that bring information from the extremeties to the spinal cord.) “So, when your immunity goes down, you have less of an ability to fight to keep that virus at bay, and it sneaks out onto a nerve and causes it to get inflamed. Then it gets to your skin and causes shingles.”
Joshua Zeichner, M.D., director of cosmetic and clinical research in dermatology at Mount Sinai Hospital in New York City, agrees. “We know that the body's stress response can impair our immunity,” he says. “The flight-or-fight response is characterized by a surge in cortisol, a hormone that prepares us for that stress, but unfortunately has other negative impacts on our health. And that surge in cortisol and impaired immunity may predispose you to a shingles outbreak.”
“I think the stress of life right now is playing a role,” says Heather D. Rogers, M.D., a faculty member at the University of Washington department of dermatology in Seattle, as well as the founder of Modern Dermatology and Doctor Rogers RESTORE. Since the COVID-19 pandemic reached crisis proportions in the spring, Dr. Rogers says she’s seeing patients present with shingles who don’t fall into predictable risk populations. “I had not seen shingles in my patients under the age of 40 in years,” she says. “Since March, I have had three patients in that age group.”
What Does the Latest Research Show?
In 2020, an analysis of a whopping 88 studies on the risk factors for shingles assessed them by category. While the greatest risk, the researchers concluded, was immunosuppression from HIV/AIDS and cancer therapies (followed by family history, physical trauma, and older age), psychological stress was also found to play a role.
An earlier review of 20 studies published in Innovations in Clinical Neuroscience focused solely on the stress-shingles connection. This research provides more affirmation, citing that the existing literature at the time was “fairly consistent in concluding that stress, stressful life events, and depressive symptoms may partially contribute to outbreaks of HZ (herpes zoster),” according to co-author Randy Sansone, M.D., professor emeritus of psychiatry and internal medicine at Wright State University School of Medicine in Dayton, OH, and director of Psychiatry Education at Kettering Medical Center.
But there’s more. In 2018, a team of Japanese researchers investigated the relationship between psychosocial factors, shingles, and postherpetic neuralgia. (About 10% to 18% of people who get shingles also experience PHN, according to the CDC.) The study, published in American Journal of Epidemiology, followed 12,522 men and women between the ages of 50 and 103 for three years. Participants were asked to asked to label the level of stress in their daily life as extremely high, high, medium, or low; describe their sense of purpose in life; and answer questions about negative life events within each past year, including changes in work and living environments, changes in human relations, and distress over economic issues.
The results were eye-opening. Men with high levels of mental stress were twice as likely to be at risk for shingles, and women who experienced negative life events—particularly changes in their work, living environment, and relationships—had a two to three-fold higher risk of PHN. Conversely, the risk of shingles was 60% lower among men and women who reported a high sense of purpose in life.
However, not all research delivers a stress-shingles connection. A 2015 study in Atlanta that pulled information from claims from private and Medicare data bases focused on nearly 40,000 individuals who’d experienced severe death or illness of a spouse (among other stressful life events) and found only 137 had developed shingles afterward. Based on statistical likelihood alone, the researchers concluded there was “no evidence” that psychological stress triggers shingles.
Stress and Shingles…in Space?
Perhaps most colorfully, a controlled study in the early 2000s followed eight astronauts to see if the physical stress of space flight—before, during, and after—was linked to the reemergence of shingles. The researchers found that while only one astronaut showed the presence of the VZV in their saliva (a marker for reactivation of the virus) before space flight, all eight did after returning to earth. The presence of VZV, according to NASA researcher Satish K. Mehta, Ph.D., indicates that the virus can reactivate in younger, healthy subjects if they experience certain intense physical stresses.
In 2019, Mehta studied a larger group of astronauts, this time searching for incidence of four herpes viruses—Epstein–Barr virus (EBV), varicella-zoster virus (VZV), herpes-simplex-1 (HSV-1), and cytomegalovirus (CMV)—and looking beyond just the physical rigors of space flight. Identifying space travel stressors including (but not limited to) social separation, confinement, sleep deprivation, circadian rhythm disruption, and anxiety, he noted a “rise in secretion of stress hormones like cortisol and adrenaline, which are known to suppress the immune system.” Immune cells—particularly those that normally suppress and eliminate viruses—are not only less effective during spaceflight but remain that way for up to 60 days after returning to earth, according to Mehta.
So, let’s bring it back down to Earth. While there’s no proven direct link between high physical and emotional stress and shingles, there’s plenty of documented causal connections to suspect stress may play at least some role in the virus’s reemergence. That means if you’re an astronaut or just an everyday American trying to stay sane during uniquely stressful times, it’s important to be on guard against all that stresses you out—whether that’s clearing for takeoff or just trying to work from home with your kids or grandkids remote learning in the same room.
“I tell my patients that the brain and the immune system are one organ, not two. What affects one, affects the other,” says Leonard Calabrese, D.O., head of the RJ Fasenmyer Center for Clinical Immunology at the Cleveland Clinic. “Stress in many forms, especially chronic stress such as depression, loneliness, or psychosocial dysfunction, can affect the immune system. The good news is that multiple modalities can alleviate stress and calm the inflammation it causes,” he says, including mindful practices like meditation, yoga, and tai chi. In addition to these practices, consistent (and quality) sleep, healthy diet, regular exercise, and not overdoing the booze have all been shown to help lower stress levels, so try to incorporate one or more into your daily routine.
In other words: Do your best to decompress to avoid a shingles attack. And, if you’re 50 or over, it goes without saying: Get a shingles vaccination to give your immune system the extra rocket boost it needs.