Herpes zoster (shingles) and chickenpox: causes and treatments

Mike Bohl, MD, MPH, ALM - Contributor Avatar

Written by Jefferson Chen, MD 

Mike Bohl, MD, MPH, ALM - Contributor Avatar

Written by Jefferson Chen, MD 

last updated: Oct 16, 2019

5 min read

One virus, two diseases. For all of you Stephen King fans, the varicella-zoster virus (VZV) is like the Pennywise the Clown of viral infections. It gives you plenty of grief when you’re a child, and it pops back up again, late in adulthood—and when you least expect it—to give you horrible pain once again. Read on and we’ll give you all the information you’ll need to keep you and your loved ones safe from chickenpox and shingles, both consequences of varicella-zoster virus infections.

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The varicella-zoster virus is a common infectious agent in the United States. It’s the cause of chickenpox (also known as varicella), the childhood rash, and herpes zoster (shingles), which occurs when VZV is reactivated later on in life. Rates of chickenpox have dropped since the introduction of the VZV vaccine in 1995, but the rates of shingles have largely remained the same (Tanuseputro, 2011). About 1.2 million people in the United States are affected by shingles every year (Yawn, 2007). The Centers for Disease Control and Prevention (CDC) believes that 1 in 3 Americans will experience shingles in their lifetimes (CDC-b, 2019).

VZV is part of the herpesvirus family, along with the viruses that cause genital herpes, oral herpes (cold sores), mononucleosis (“mono”), and others. Like the virus that causes genital herpes, VZV is great at dodging your immune system and hiding out in your nerves. Learn more about herpesviruses here.

How is varicella-zoster virus transmitted?

The varicella-zoster virus is well known to healthcare providers as being highly contagious, meaning that it spreads from one person to another very easily. You might know this very well if you attended a ‘chickenpox party’ as a kid. (For the record, we think that chickenpox parties are a bad idea and risk numerous complications including brain damage and pneumonia (CDC-b, 2019). VZV is spread person to person through infected airborne droplets or direct contact. It typically first infects cells involved in your immune system, which then spread the virus throughout your body. From there, it attacks your skin cells and creates the rash and fluid-filled blisters that we commonly see with chickenpox. From 2 days before symptoms appear until the blisters crust over and scab, you can transmit the disease to someone else. Before scabs are formed, people with chickenpox or shingles should avoid contact with other people. This might mean staying home from work or school. As the symptoms start to fade, VZV then travels back up your nerve endings and hides out in a bundle of nerve cells called the dorsal root ganglia, biding its time until your immunity drops, when it can wreak havoc once again.

What is chickenpox?

Chickenpox is the infectious disease that occurs during the acute, invasive phase of the VZV infection you typically get as a child. In most children, chickenpox is usually not severe. The first symptoms typically include a fever, feeling ill, sore throat, upset stomach, or loss of appetite. After a day or so, the rash will appear. For those of you that haven’t seen chickenpox before, it looks like clusters of small, itchy, and red blisters that form on the face, chest, back, arms, and legs. New blisters will appear for a few days. In around six days, the blisters will form scabs, which will fall off after a week or two. In unvaccinated adults, chickenpox can be more severe. Adults with chickenpox have a higher risk of serious complications including pneumonia and encephalitis (brain inflammation).

Vaccinations against VZV, also known as the chickenpox vaccine, can be highly effective in preventing the infection. The vaccine is typically given in two doses, the first at 12-18 months and the second at 4-6 years old (CDC-a, 2018). Across multiple studies, the first dose of the vaccine is 80% effective at preventing chickenpox and almost eliminates the chance to get severe symptoms (Marin,2016). The second dose of the vaccine results is 92% effective in preventing chickenpox.

Some simple treatments can help someone with chickenpox. First, the symptoms of chickenpox should be treated. This can include acetaminophen (brand name Tylenol) for fever and antihistamine medications like loratadine (brand name Claritin) for itchiness. Skin treatments like lotions may work, though this has not been scientifically proven. Note that you should not give aspirin to children because it puts them at risk for Reye syndrome, which can be extremely dangerous. Antiviral medications may be appropriate to treat chickenpox, especially in adults, people with a weak immune system, and children that haven’t been vaccinated. If your healthcare provider finds it necessary, antiviral medications like acyclovir and valacyclovir can reduce the severity and duration of symptoms.

What is shingles?

Shingles (herpes zoster) is the disease that occurs when VZV reactivates from your nerve cells. Reactivation typically happens in older adults or during periods of low immunity. The symptoms of shingles usually start with itching, burning, or tingling on a patch of skin on one side of the body. Within one or two days, a rash will break out in a band on one side of the body. Your healthcare provider may call this band a ‘dermatome.’ The rash is typically painful, itchy, and tingly and will have small fluid-filled blisters just like chickenpox. New blisters will keep popping up over the next three to five days. They’ll then crust over and heal over two to four weeks.

Anyone that’s had chickenpox or had the varicella vaccination in the past can get shingles, though children that get the varicella vaccine are at a lower risk. A person’s risk of getting shingles increases after age 50. People whose immune systems are compromised, including people with HIV, people on chemotherapy, or transplant recipients, are at especially high risk. Most people only get shingles once in their lifetime.

Unfortunately, shingles can come with a nasty complication called post-herpetic neuralgia (PHN). This complication is marked by burning, acute pain that can range from mild to excruciating and last for weeks to years after it begins. The risk of PHN after shingles increases with age. The CDC estimates that 10–13% of shingles cases result in PHN (CDC-c, 2019). Healthcare providers will typically try gabapentin (brand name Neurontin), pregabalin (brand name Lyrica), and tricyclic antidepressants to treat PHN. Because the symptoms of PHN may be chronic, you may need to be on these medications long-term (Johnson, 2014).

So how can we prevent this from happening? A herpes zoster vaccine called Shingrix was released in 2017 and is now recommended by the CDC for the prevention of shingles in people 50 years and older (CDC-b, 2018). It consists of two doses, given two to six months apart. You’re well protected after you get vaccinated: in one trial, completing two doses of the Shingrix vaccine decreased the risk of developing shingles over a period of three years by 97% (Lal, 2015). If Shingrix isn’t available or if you’re allergic to it, you might be able to get Zostavax. Zostavax is another shingles vaccine and is approved in people 60 and older.

If you do get shingles, speak to your healthcare provider. Prompt treatment with antiviral medications can lessen pain, encourage healing, and decrease your risk of post-herpetic neuralgia. Valacyclovir (brand name Valtrex; see Important Safety Information), famciclovir, and acyclovir, typically given over a week, are frequently used to treat shingles.

What are the risk factors for acquiring the varicella-zoster virus?

People without immunity to VZV are at the highest risk of getting the infection. These are people that never had chickenpox and were never immunized against VZV. The best way to decrease your risk of getting VZV is to get vaccinated. This is especially important for children, healthcare workers, and people that work in schools or daycare facilities. If you’re not sure if you’ve gotten chickenpox or had the vaccine in the past, your healthcare provider can send a simple blood test to evaluate your immunity.

You might also be wondering, can you get chickenpox twice? The answer is yes, but it is rare, especially in people with normal immune systems (Dyer, 2016).

Does varicella-zoster virus ever go away?

No, unfortunately, VZV is a lifelong infection. Once you get it, there is no way to get rid of it. However, vaccinations against chickenpox and shingles can prevent or lessen the symptoms if you get infected. Additionally, antiviral medications, such as acyclovir, famciclovir, or valacyclovir, are effective at treating VZV when you experience symptoms. Speak with your healthcare provider if you are worried about chickenpox or shingles in you or a loved one.

DISCLAIMER

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.


How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

October 16, 2019

Written by

Jefferson Chen, MD

Fact checked by

Mike Bohl, MD, MPH, ALM


About the medical reviewer

Dr. Mike is a licensed physician and a former Director, Medical Content & Education at Ro.