In some cases, COVID-19 infection can affect the immune system, causing a reactivation of the herpes zoster virus if a person has already had chickenpox. This can cause shingles symptoms.

Neither the COVID-19 virus nor the COVID-19 vaccines can cause a shingles outbreak since shingles is caused by a different virus entirely. But that does not mean there is no link between the two.

To better understand the relationship between the two, let’s look at some details about the herpes zoster virus and SARS-CoV-2, responsible for shingles and COVID-19, respectively, and what the research currently suggests about the link between the two conditions.

Shingles results from a reactivation of the herpes zoster virus (HSV), which first takes the form of chickenpox. If you have chickenpox, you can develop shingles if the HSV virus reactivates.

HSV can reactivate and cause shingles if your immune function declines, including due to aging or a health condition.

If you have COVID-19, the immune system may be compromised or distracted, leading to an increased risk of HSV reactivation. A 2022 study found that people with COVID-19 had a 15% higher risk of shingles.

What is shingles reactivation, and why does it occur?

Many people born in or before 1980 in the U.S. had a chickenpox infection or have had exposure to HSV. Others may have received a chickenpox vaccination.

Whether you have acquired varicella or been vaccinated against it, the virus lies dormant in certain nerve cells after exposure. Years after your first encounter with chickenpox, the virus can be reactivated in the form of shingles, though this is less likely if your exposure was a vaccination.

While most people only get shingles once in their lifetime, the virus can be reactivated multiple times.

Factors that may increase your risk for shingles reactivation can include:

  • older age, which naturally causes a decline in your immune system’s response
  • immune-suppressing medications, such as chemotherapy, corticosteroids, and anti-inflammatory medications
  • health conditions that target your immune system, like Crohn’s disease, HIV, lupus, and rheumatoid arthritis
  • other infections that temporarily weaken your immune system, including COVID-19
  • procedures, such as organ transplants, that require the use of immunosuppressant medication
  • stress

People who are at a higher risk for shingles are also at a higher risk for severe symptoms of COVID-19.

Can COVID-19 vaccination reactivate shingles?

While rare, there are reports of people developing shingles after a COVID-19 vaccination. In these cases, the vaccination does not cause shingles but may affect the immune system and increase the risk of shingles reactivating.

When your immune system is compromised or distracted fighting off another virus, it tends to give the shingles virus a chance to reactivate.

A small 2021 study involving 491 vaccinated people in Israel showed that six participants experienced shingles for the first time after getting their first dose of the COVID-19 vaccine. All six individuals had pre-existing conditions that lowered their natural immune response, and all six fully recovered after developing shingles.

Getting the shingles vaccine can help prevent the reactivation of HSV. It can also reduce the risk of severe symptoms and complications if you do experience HSV reactivation.

Clinical trials

Researchers are currently working toward getting a better understanding of the relationship between COVID-19 and the herpes zoster virus that causes shingles.

One clinical trial involving residents of a nursing home has been investigating how the shingles vaccine (Shingrix) can improve the body’s immune response to the seasonal flu and COVID-19.

COVID-19 does not cause shingles — neither do any of the currently available vaccines designed to protect you against COVID-19.

We know this because shingles is caused by a different virus entirely. We do not yet know whether getting a COVID-19 vaccine or contracting SARS-CoV-2 might increase the risk of reactivating the virus that causes shingles.

Speak with a doctor if you have any concerns about getting vaccinated.