Shingles comes from the chickenpox virus already in your body
You cannot catch shingles from someone else. Instead, shingles develops when the varicella-zoster virus — the same virus that causes chickenpox — wakes up inside nerve tissue where it has been dormant for years or decades. If you had chickenpox as a child, the virus never fully left your body. It stayed inactive in nerve cells near your spinal cord. Later in life, that virus can reactivate and cause shingles, a painful rash that typically appears on one side of your body.
The reason the virus reactivates is not fully understood, but doctors know that a weakened immune system makes reactivation much more likely. Your immune system normally keeps the virus in check. When your immune defenses drop — whether from age, stress, illness, or certain medications — the virus can break free and travel along a nerve to your skin.
Key Takeaways
- Shingles only develops in people who have had chickenpox; you cannot catch shingles from another person.
- The varicella-zoster virus remains dormant in your nerve tissue after chickenpox and can reactivate decades later.
- Your risk of shingles increases significantly after age 50, when immune function naturally declines.
- A weakened immune system from illness, stress, injury, or certain medications can trigger the virus to reactivate.
- The shingles vaccine substantially reduces your risk of developing the condition and the severity of pain if you do develop it.
Why the virus reactivates: immune system weakness
Your immune system acts as a guard keeping the dormant chickenpox virus contained. When that guard weakens, the virus seizes the opportunity to multiply and spread. Several common situations can lower your immune defenses enough to allow reactivation.
Age is the single strongest risk factor. After age 50, your immune system naturally becomes less effective at controlling infections. This is why shingles is far more common in older adults. A person in their 60s is roughly three times more likely to develop shingles than someone in their 40s.
Serious illness can also trigger shingles. If you have HIV, cancer, or another condition that damages immune cells, your risk rises sharply. Even temporary immune suppression from a severe infection, major surgery, or significant physical trauma can be enough to reactivate the virus. Certain medications — particularly those used to prevent organ rejection after transplant or to treat autoimmune diseases — directly suppress immune function and increase shingles risk.
Emotional and physical stress can weaken immune response over time. Chronic stress, sleep deprivation, or a period of intense emotional strain may contribute to reactivation, though the connection is less direct than with illness or age.
Who is most likely to develop shingles
Your age and health history determine much of your shingles risk. People over 50 account for the majority of shingles cases. Within that group, risk continues to climb with each decade of life.
Certain medical conditions put you at higher risk regardless of age. If you have HIV, cancer, or an autoimmune disease like rheumatoid arthritis or lupus, your chances of developing shingles are substantially elevated. People taking immunosuppressive medications — whether for transplant rejection prevention, cancer treatment, or autoimmune disease management — face increased risk.
A history of severe chickenpox infection may also increase shingles risk later, though most people who had chickenpox will never develop shingles. Conversely, people who received the chickenpox vaccine as children have a lower risk of shingles than those who had the natural infection, because the vaccine virus is weaker and less likely to reactivate.
The path from dormant virus to active shingles
Once the varicella-zoster virus reactivates in a nerve cell, it begins to multiply. The virus then travels along the nerve fiber toward the skin, a process that can take several days. This is why shingles typically appears in a band or stripe pattern — it follows the path of a single nerve.
As the virus reaches the skin, it infects skin cells and causes inflammation. This is when you develop the characteristic rash: fluid-filled blisters that appear in a line or cluster on one side of your body. The rash is usually preceded by pain, tingling, or burning in the same area, sometimes days before any visible signs appear.
The virus does not spread through your bloodstream to other parts of your body the way chickenpox does. Instead, it stays localized to the area supplied by the infected nerve. This is why shingles rash does not cover your whole body — it affects only the skin region connected to the reactivated nerve.
Can you catch shingles from someone with the condition
You cannot catch shingles itself from another person. However, someone with active shingles can transmit the varicella-zoster virus to people who have never had chickenpox and are not vaccinated. Those people will develop chickenpox, not shingles.
The virus spreads through respiratory droplets or direct contact with the shingles rash. If you have shingles, you are contagious until all the blisters have crusted over, which typically takes one to two weeks. People at highest risk from exposure are infants too young for the chickenpox vaccine, pregnant women who have never had chickenpox, and people with severely weakened immune systems.
If you have shingles, cover the rash with clothing or bandages and avoid contact with people in these high-risk groups until the blisters crust over. This prevents transmission of chickenpox to vulnerable individuals.
How the shingles vaccine reduces your risk
Two vaccines can prevent shingles or reduce its severity: Zostavax (a live vaccine) and Shingrix (a recombinant vaccine). Shingrix is now the preferred option because it is more effective and safe for a wider range of people, including those with weakened immune systems.
Shingrix is given as two doses, two to six months apart. It reduces the risk of developing shingles by roughly 90 percent in people over 50. Even if vaccinated people do develop shingles, the illness is typically much milder, with less severe pain and faster healing.
The vaccine works by training your immune system to recognize and control the dormant virus more effectively. It does not eliminate the virus from your body — nothing can do that — but it strengthens your immune response so the virus is less likely to reactivate. The protection remains strong for at least seven years after vaccination, and likely much longer.
Frequently Asked Questions
Can you get shingles more than once?
Yes, though it is uncommon. Most people who develop shingles once have strong enough immune recovery that reactivation does not happen again. However, people with severely weakened immune systems or those over 80 can develop shingles a second or even third time. Each episode follows the same pattern: reactivation in a nerve, followed by a localized rash.
Does stress alone cause shingles?
Stress alone is unlikely to cause shingles in a healthy person with a strong immune system. However, chronic stress combined with age or another factor that weakens immunity may contribute to reactivation. Stress is one piece of a larger picture that includes your age, overall health, and immune function.
If I never had chickenpox, can I get shingles?
No. Shingles only develops in people who have had chickenpox or received the chickenpox vaccine, because the virus must already be present in your nerve tissue. If you have never had chickenpox and were not vaccinated, you cannot develop shingles — though you could develop chickenpox if exposed to someone with active chickenpox or shingles.
Does the chickenpox vaccine prevent shingles later?
The chickenpox vaccine reduces shingles risk compared to people who had natural chickenpox infection, but it does not eliminate the risk entirely. People vaccinated as children still have some chance of developing shingles later in life. This is why the shingles vaccine (Shingrix) is recommended separately for adults over 50, regardless of chickenpox vaccination history.
What should I do if I think I have shingles?
Contact your doctor as soon as possible. Antiviral medications work best when started within three days of the rash appearing, so early diagnosis matters. Your doctor can confirm shingles and discuss treatment options to reduce pain and speed healing. Do not wait to see if it goes away on its own.