What Causes Shingles to Activate?

Shingles, also known as herpes zoster, is a viral infection caused by the varicella-zoster virus (VZV), the same virus responsible for chickenpox. After a person recovers from chickenpox, the virus can remain dormant in nerve cells near the spinal cord and brain for many years. Shingles occurs when the virus reactivates and travels along the nerves to the skin, causing a painful rash. The exact triggers for shingles reactivation are not fully understood, but several factors can increase the risk of activation:

  • Age: Shingles is more common in older adults, and the risk increases significantly after the age of 50. The reason for this age-related increase in risk is not entirely clear, but it is thought to be related to age-related changes in the immune system.
  • Weakened Immune System: A weakened immune system due to illness, stress, or medications can increase the risk of shingles. Conditions such as HIV/AIDS, cancer, organ transplantation, or long-term use of corticosteroid medications can suppress the immune response, making it easier for the virus to reactivate.
  • Stress: High levels of physical or emotional stress can weaken the immune system and trigger shingles in some individuals. Stress can affect the body’s ability to keep the virus in check.
  • Other Illnesses: Certain illnesses that cause fever or widespread inflammation can potentially trigger shingles reactivation. These include the flu, pneumonia, and other infections.
  • Injury or Trauma: Physical injury or trauma to a specific area of the body may irritate the nerves and potentially trigger shingles in that region. However, this is relatively uncommon.
  • Medications: Some medications, such as immunosuppressants or drugs used to treat autoimmune diseases, can increase the risk of shingles by suppressing the immune system.
  • VZV Exposure: Exposure to someone with chickenpox or shingles can sometimes lead to shingles reactivation, especially in individuals with weakened immune systems.
  • Gender: Women and men have similar overall risks of developing shingles, but some studies suggest that women may be more susceptible to shingles during and after pregnancy.

It’s important to note that not everyone who has had chickenpox will develop shingles, and the factors leading to reactivation can vary from person to person. Additionally, shingles can be contagious to individuals who have not had chickenpox or who have not been vaccinated against VZV, so it’s essential to take precautions to prevent the spread of the virus, especially during the active phase of shingles.

Vaccination with the shingles vaccine (Shingrix) is recommended for individuals aged 50 and older to reduce the risk of shingles and its complications. If you believe you may be at risk or have questions about shingles prevention or treatment, consult a healthcare provider for personalized advice and recommendations.