Shingles: The Uninvited Guest at the MS Party
As an elder millennial, I grew up in the heyday of “chickenpox parties”. Children were sent to play with friends, cousins, and neighbours when they had the telltale rash in the hopes of ensuring that they caught the common childhood illness at an early age. This “catch it early” approach made sense because a vaccine didn’t yet exist and it was known that the virus tended to hit harder when caught later in life. I had chickenpox as a toddler, picked up from my babysitter's child. These days, chickenpox is nearly unheard of because the varicella vaccine has been added to the roster of routine childhood immunizations. However, with the recent rise in anti-vaccine sentiment, we may see a rise in chickenpox infections.
Chickenpox parties were captured for posterity on The Simpsons.
This article is about shingles, so why are we talking about chickenpox? Well, let’s start with an understanding of what shingles is and where it comes from.
Shingles is an infection caused by the varicella-zoster virus (VZV). VZV causes chickenpox as a primary infection. After a person has had chickenpox, VZV remains dormant in the dorsal root ganglia. Shingles occurs when there is a reactivation of VZV. Shingles typically causes a painful rash that appears as a stripe of fluid-filled blisters. It commonly appears wrapped around one side of the torso, but it can also appear on the face, neck, and other body parts. A sharp, burning, or stabbing pain commonly accompanies the rash and may precede the appearance of the rash. Shingles also commonly presents with flu-like symptoms, such as fever, headache, fatigue, and body aches.
Postherpetic neuralgia is the most common complication of shingles. The likelihood of developing postherpetic neuralgia varies depending on factors including age, overall health status, and the severity of the shingles outbreak. As many as 30% of people who have had shingles develop postherpetic neuralgia. It causes persistent pain in the area where the shingles rash occurred. Postherpetic neuralgia occurs when VZV damages nerve fibres during the acute phase of shingles. After the rash has healed, the damaged nerves continue to send pain signals to the brain. This results in chronic pain which can last for months or years. The pain caused by postherpetic neuralgia can be constant or intermittent, and it is typically described as burning, stabbing, or shooting. Sometimes other altered sensations present, such as tingling, itching, or numbness. The pain caused by postherpetic neuralgia can be debilitating.
When shingles rash appears on a patient’s head it must be closely monitored due to the risk of the infection spreading to the patient’s eyes. When shingles infects the eyes, it is important to see an ophthalmologist immediately, because it can cause permanent vision loss.
Early treatment can help to reduce the severity and duration of symptoms, and can reduce the likelihood of complications like postherpetic neuralgia. Several antiviral medications are available to treat shingles, most commonly acyclovir, famciclovir, and valacyclovir.
Since MS causes damage to the central nervous system, people with MS who get shingles are more likely to have more severe shingles symptoms and complications like postherpetic neuralgia.
About 1 in 3 people will develop shingles in their lifetime. People living with MS are significantly more likely to develop shingles compared with the rest of the population. Most studies indicate that those living with MS live with roughly double the risk of developing shingles in their lifetime as compared with the general population. Of particular note is that shingles, while generally common in older adults, is far more prevalent in younger adults living with MS. Younger adults (18-49 years of age) living with MS are over three times more likely to develop shingles than immunocompetent adults in this age range.
A component of this increased risk of developing shingles in those living with MS is that many use immunosuppressive and immunomodulating agents to treat their MS. The newer and higher efficacy Disease Modifying Therapies (DMTs) for MS have more profound immunosuppressive and immunomodulating effects than the older DMTs, known as the “ABC drugs” – Avonex, Betaseron, and Copaxone. Higher levels of immunosuppression are known to correlate with higher incidence rates of shingles. This is not the only factor that causes those living with MS to be at an increased risk of developing shingles, as even those living with untreated MS are at a significantly heightened risk of developing shingles as compared with the general population. High-dose steroids, often used during relapses, may also increase the risk of a shingles outbreak. Many living with MS who take these higher efficacy DMTs implement strategies to reduce their risk of developing infections. There’s a reason that you’ll often see those of us living with MS still wearing masks and sanitizing our hands and acting like you are a plague rat if you sneeze around us even in post-pandemic times. Those immunosuppressive and immunomodulating agents that do such a great job of keeping MS relapses at bay come at a cost to our immune systems, leaving us more vulnerable to viruses, bacteria, and fungi. Additionally, developing an infection, whether a cold, flu, urinary tract infection, shingles, or any number of other common infections, puts those of us living with MS (whether taking a DMT or not) at risk for pseudo-relapses (the temporary exacerbation of MS symptoms) or relapses (new MS lesions in our brain or spinal cord, and all the lovely symptoms that go along with new lesions). Shingles poses a unique challenge, because it lurks in our own bodies waiting to reactivate. As a result, most of our risk mitigation strategies, like mask-wearing, hand-washing, and avoidance of sick people don’t work here. The only risk mitigation strategies available for shingles are stress reduction (wish me luck with that one as a lawyer and mother to a 4-year-old boy, ha!) and vaccination.
There is a vaccine that helps to prevent the development of shingles. Shingrix is fully covered by OHIP (that’s Ontario’s public health care plan for readers outside of Ontario) for seniors between the ages of 65 and 70 who have not previously received a shingles vaccine. It is also available for private purchase and some private health insurance plans cover the cost of this vaccine. The National Advisory Committee on Immunication recommends Shingrix for anyone age 50 and older who is not allergic to any ingredients of the vaccine. Health Canada has also recently approved Shingrix for adults aged 18 years and older who are or who will be at increased risk of shingles due to immunodeficiency or immunosuppression. Shingrix is given as a series of two doses, delivered 2 to 6 months apart. Shingrix can reduce a person’s chance of getting shingles by over 90 percent. Shingrix is considered safe for use in people living with MS.
The varicella vaccine may serve as a two-for-one vaccination. It significantly reduces the likelihood of chickenpox in children, and in doing so it may also reduce the likelihood of developing shingles later in life. It’s still early days in evaluating the efficacy of the varicella vaccine in preventing shingles. It was first introduced in Japan and Korea in 1989, it was approved in 1995 in the United States, and in 1999 in Canada. Those first recipients of the varicella vaccine are now in their late 20s or early 30s, and not yet at the age when shingles is most common. However, early indications show that the varicella vaccine may also significantly reduce the incidence of shingles. Shingles can still present in someone who has received the varicella vaccine. The varicella vaccine is a live attenuated (weakened) virus, so it can become latent after vaccination and later reactivate, just as it would following a chickenpox infection. It is not yet clear whether those who received the varicella vaccine as a child will require a vaccine against shingles later in life.
My dad developed shingles a few years ago, and he has struggled with postherpetic neuralgia ever since. Knowing his experience with shingles and knowing that I am at a heightened risk for developing shingles both due to having MS and due to the treatment that I take for MS was enough to have me jump at the chance to get vaccinated when I became eligible. If that wasn’t enough, a member of one of my MS Facebook communities who has come to be a friend encourages us all to get the Shingrix vaccine when eligible, as she’s had shingles 26 times. That information also lit a fire under me to get vaccinated pronto. Unfortunately, it wasn’t until after I had already started taking Kesimpta that Health Canada approved use of the Shingrix vaccine for adults aged 18 years and older who are or who will be at increased risk of shingles due to immunodeficiency or immunosuppression caused by known disease or therapy. This announcement came in November 2021, just a couple of months after I had starting taking Kesimpta. Vaccines are less effective when taking an immunosuppressive agent, like Kesimpta. As a result, doctors will usually suggest ensuring all recommended vaccines are taken before starting on one of these DMTs. Nonetheless, my neurologist still endorsed my receiving the Shingrix vaccine once I was eligible. I was told to time all vaccinations smack in the middle of monthly Kesimpta doses to give the vaccine the best chance of efficacy.
I had a rather sore arm after each dose of Shingrix, and I was tired for about a day after my second dose. However, if it prevents me from developing shingles, it will have been well worth it. Other common side effects to Shingrix include redness and swelling at the injection site, headache, fever, and nausea.
Being of older age and being immunocompromised are the most common risk factors for shingles. If you are reading this and fall into either or both of these categories, I hope that this will inspire you to consider vaccination. As always, consult with your medical team to determine the appropriate course of action for your unique medical needs.
