Varicella-Zoster Virus: Overlap Between Chickenpox and Shingles
Learn how to reduce transmission
Medically reviewed by Jonathan B. Jassey, DO
Varicella-zoster virus is an infection that causes multiple illnesses. It first causes chickenpox (also called varicella), an itchy rash. Then, it goes dormant in the nerves. If the immune system is weakened, it can come out again as shingles (herpes zoster), a painful rash along a nerve.
Varicella-zoster virus is a member of the herpesviridae family of viruses, making it a herpesvirus. It can infect children or adults. It is very contagious and can be dangerous in people with weakened immune systems.
This article will explain how varicella-zoster virus is linked to herpes, shingles, and chickenpox, how to treat it, and how to prevent it. It also will explain how the varicella-zoster virus vaccine works.
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How Is Varicella Zoster Similar and Different From the Illnesses It Causes
Varicella zoster is a virus in the herpesvirus family associated with illnesses such as chickenpox, shingles, and herpes. It can manifest in different ways and is related to other viruses.
Chickenpox
Chickenpox is a disease that arises when you’re first infected with the varicella-zoster virus. Many people will be infected with the varicella-zoster virus as children and have a case of chickenpox. Others will receive the varicella vaccine and avoid infection with the varicella-zoster virus altogether.
Chickenpox causes an itchy, blister-like rash on the chest, back, and face. It can then spread to the entire body. The varicella-zoster virus infection that causes chickenpox can cause serious, life-threatening complications. It’s more dangerous to babies, pregnant people, and people with weakened immune systems.
Shingles
Shingles is a disease caused by the reactivation of the varicella-zoster virus. The virus stays dormant in the nerves until your immune system weakens. It then spreads to the skin around the nerves. You can have shingles if you’ve had varicella (chickenpox). About one-third of people will get shingles at some time.
Shingles can appear at any age but becomes more common later in life. It causes a painful and often itchy, blistery rash. The rash typically shows up on just one side of the face or body. The blisters scab over in about seven to 10 days. They’ll usually disappear within two to four weeks.
Herpes
Herpes is an infection with the herpes simplex virus. Depending on what type of herpes virus it is and the part of the body with the infection, it can cause oral or genital sores. Complications can arise in newborn babies and people with weakened immune systems.
Varicella zoster virus is a different type of herpesvirus. The herpes family contains more than 100 known viruses. Eight of these viruses are known to cause diseases in humans. These include:
Varicella-zoster virus
Human herpesvirus 6 (variants A and B)
Human herpesvirus 7
Kaposi's sarcoma (human herpesvirus 8)
Related: Is Chickenpox Herpes?
Is Varicella Zoster Contagious?
Varicella-zoster virus spreads from person to person through close contact. It is very contagious, especially when it presents as chickenpox. When one person has chickenpox, up to 90% of the people they come into contact with who do not have immunity against the virus will get chickenpox.
People can develop immunity to chickenpox by being previously exposed and getting chickenpox or by having the chickenpox or shingles vaccine.
If you have chickenpox, you’re contagious for up to two days before you get the rash. You can transmit the virus to others until all your spots have crusted or scabbed over.
If you’ve been vaccinated and get a breakthrough case of chickenpox, you may have spots that don’t scab. In this case, you’re contagious until no new lesions have appeared for 24 hours.
People with chickenpox are more likely to transmit the varicella-zoster virus than people with shingles. But someone with shingles is still contagious and can transmit the virus to others. In this case, the virus spreads through the fluid from the shingles blisters or by breathing in the virus from the blisters.
If someone without immunity to chickenpox acquires varicella-zoster virus from someone with shingles, they will get chickenpox, not shingles. Then, they’ll be at risk of developing shingles later in life.
To reduce the risk of transmitting chickenpox when you have the infection, avoid people who haven’t gotten the chickenpox vaccine or previously had chickenpox.
To avoid transmission to people at higher risk for complications from varicella zoster, you’ll want to avoid people until your rash scabs over, especially:
Pregnant people who are not immune to varicella zoster through having chickenpox or the chickenpox vaccine
Premature or low birth weight infants
People with weakened immune systems, including those on immunosuppressive drugs, in cancer treatment, with organ transplants, and with human immunodeficiency virus (HIV) infection.
Slow the spread of varicella zoster from a shingles outbreak by covering the rash. Unlike chickenpox, shingles is not contagious before the rash appears.
Avoid touching or scratching the rash for either infection, and regularly wash your hands for at least 20 seconds.
Effectiveness of Varicella-Zoster Vaccine
Most infections with varicella-zoster can be avoided with chickenpox and shingles vaccines. Both effectively stop the virus infection or the symptoms of its reactivation.
Two chickenpox vaccines are available. Varivax works only against chickenpox. ProQuad is a combination vaccine that prevents measles, mumps, rubella, and varicella. Kids and anyone who has not been vaccinated or had chickenpox should get two doses. Kids should get chickenpox shots between 12 and 15 months old and ages 4 and 6 years.
The chickenpox vaccine is more than 90% effective at preventing a varicella-zoster virus infection that causes chickenpox.
The shingles vaccine (Shingrix) is available for adults 50 and older. It is also given to adults with weakened immune systems. Shingrix helps prevent shingles and other complications from varicella-zoster virus.
You can get the shingles vaccine even if you've:
Had shingles
Received a Zostavax vaccine in the past (another shingles vaccine now discontinued)
Received a varicella (chickenpox) vaccine
In older adults with healthy immune systems, Shingrix is more than 90% effective at preventing shingles and a complication of varicella-zoster virus called postherpetic neuralgia.
Shingrix helps your body fight off the re-emergence of varicella zoster for at least seven years after vaccination. This vaccine is between 68% and 91% effective in preventing shingles for those with weakened immune systems.
If you don’t know and can't remember if you’ve had chickenpox or the vaccine, you can ask your healthcare provider to check for varicella-zoster IgG antibodies with an ELISA (enzyme-linked immunoassay) test. A positive antibody test for varicella zoster virus would indicate that you’re immune to varicella zoster because of a previous infection or vaccination.
What Is an Antibody?
An antibody is a complex protein made by your immune system. They are tailor-made to fight certain infections. You only produce antibodies against a virus if you’ve been exposed to it or a part of it (like one of its proteins in a vaccine).
Symptoms of Varicella-Zoster Virus
The symptoms of varicella-zoster virus vary based on whether it’s an initial infection causing chickenpox or a reemerging infection causing shingles and other complications.
Chickenpox Symptoms
When the varicella-zoster virus causes chickenpox, it typically shows up as an itchy rash of fluid-filled blisters. The rash eventually scabs over. Chickenpox usually lasts about four to seven days.
The rash often first appears on the chest, back, and face. It then spreads over the entire body. Blisters can form anywhere, including the mouth, eyelids, or genital area.
Other symptoms can show up one or two days before the rash, when you’re likely contagious as well. These include:
Fever
Tiredness
Loss of appetite
Headache
Related: What Does Chickenpox Look Like?
Shingles Symptoms
The first signs and symptoms of a shingles outbreak are pain, itching, or tingling in the area where the rash develops. These feelings may appear several days before the rash does. The rash is usually isolated to a single band of skin around the left or right side of the body or face.
Other symptoms of shingles include:
Fever
Headache
Chills
Upset stomach
Related: What Shingles Looks Like
Risks and Complications of Varicella Zoster
In vulnerable populations, varicella-zoster virus infections can cause complications.
People at Higher Risk
The risks of developing complications from varicella-zoster virus are higher in vulnerable populations, including newborns, especially those born preterm, pregnant people without immunity, older people, and people with weakened immune systems.
Complications of Chickenpox
Some people with severe complications from chickenpox can become so sick that they must be hospitalized. Chickenpox can also cause death.
Chickenpox complications include:
Bacterial infections of the skin
Pneumonia (lung infection and inflammation)
Infection or swelling of the brain
Bleeding problems
Blood infection (sepsis)
Dehydration
Complications of Shingles
The most common complication of shingles is long-lasting nerve pain that stays even after the rash heals. About 10% to 18% of people with shingles have this complication, called postherpetic neuralgia (PHN).
Other complications of shingles include:
Shingles on the face that can cause vision loss and other eye problems
Bacterial infection of the shingles rash
Pneumonia
Hearing problems
Brain inflammation
Death
How to Treat Varicella-Zoster Virus
Once you’ve had chickenpox, the varicella-zoster virus never fully leaves your body. It hides out in the nerves. Having had a bout of chickenpox means you’ll always be at risk of developing shingles. Thankfully, most people will only have shingles once—it rarely returns.
Currently, the best option is vaccination to prevent infection and reactivation. Barring that, treatment options can help reduce the symptoms of these infections.
Chickenpox Treatment
Most people only need to care for their chickenpox with at-home treatments. These treatments aim to relieve chickenpox symptoms and prevent skin infections.
Home treatments for chickenpox include:
Apply calamine lotion.
Take a cool baking soda, uncooked oatmeal, or colloidal oatmeal bath.
Keep fingernails trimmed short to minimize scratching.
Minimize scratching to prevent spread and skin infections.
If you scratch a blister, wash your hands with soap and water for at least 20 seconds.
Take Tylenol (acetaminophen) to relieve fever. Avoid Advil and Motrin (ibuprofen)—it may increase the risk of a life-threatening bacterial skin infection. Do not give aspirin to children or teenagers.
Let a healthcare provider know if you’ve been exposed to chickenpox or shingles if you or your child:
Has never had chickenpox and is not vaccinated
Is pregnant
Has a weakened immune system
Is younger than 1 year old
Is older than age 12
Your healthcare provider may put you on the antiviral medicine Zovirax (acyclovir).
If none of these apply, you’d only need to contact a healthcare provider if you or your develops the following symptoms:
Fever for more than four days
Fever above 102 degrees F
Skin that is red, warm, tender, or leaking pus
Difficulty waking up or confused behavior
Difficulty walking
Stiff neck
Frequent vomiting
Difficulty breathing
Severe cough
Severe abdominal pain
Rash with bleeding or bruising (hemorrhagic rash)
Shingles Treatment
A healthcare provider will treat shingles with antiviral medicines to shorten the length and severity of the illness. These should be started as soon as possible after the rash appears:
Zovirax (Acyclovir)
Valtrex (Valacyclovir)
Famvir (Famciclovir)
Wet compresses, calamine lotion, and warm oatmeal baths can help relieve the symptoms of shingles. You can also take either over-the-counter or a prescription pain-relief medicine. Discuss which is most appropriate with a healthcare provider.
Related: Valacyclovir vs. Acyclovir: Similarities & Differences
Summary
The varicella-zoster virus (VZV) causes multiple illnesses. Initially, it causes chickenpox (varicella) with an itchy rash. After chickenpox, the varicella-zoster virus sits dormant in the nerves. The virus can reactivate as shingles (herpes zoster). This causes a painful rash along a nerve pathway.
Varicella-zoster virus belongs to the herpesviridae family and is a herpesvirus. It can infect both children and adults. It is highly contagious. Varicella-zoster virus spreads through close contact. It can spread before the chickenpox rash appears. You're contagious until all spots have crusted.
Shingles is less contagious than chickenpox. But it can still spread, mainly through the fluid from shingles blisters.
Complications of chickenpox pose risks to those with weaker immune systems. This includes very young children, older adults, and pregnant people. Complications can be severe in these populations. Chickenpox complications include skin infections, pneumonia, and brain inflammation.
The most common shingles complication is postherpetic neuralgia, a long-lasting nerve pain. Other potential risks of shingles include vision loss and bacterial infections.
The chickenpox and shingles vaccines both build immunity to varicella-zoster virus. If you have varicella-zoster virus antibodies, you've had chickenpox or the vaccine.
There is no cure for varicella-zoster virus, but vaccination can prevent it. Home remedies can help manage chickenpox symptoms and prevent skin infections. Sometimes, a healthcare provider will prescribe an antiviral medication for chickenpox. This is also a common shingles treatment to reduce symptoms, speed healing, and reduce complications.
Read the original article on Verywell Health.
