How Your Immune System Influences Shingles Risk

What Causes Shingles?

Shingles is caused by the varicella-zoster virus. This is the same virus that causes chickenpox.

After a person recovers from chickenpox, the virus does not completely leave the body. Instead, it remains dormant within the nervous system.

For many people, the virus remains inactive for the rest of their lives. However, if the virus becomes active again, it can travel along the nerves and cause shingles.

This is why only people who have previously had chickenpox can develop shingles.

How Does the Virus Stay in the Body?

Following chickenpox infection, the varicella-zoster virus remains hidden within nerve cells.

The immune system continuously helps keep the virus under control. Most of the time, people are completely unaware that the virus is still present.

However, changes in immune function can sometimes allow the virus to reactivate. When this happens, shingles develops.

The Role of the Immune System

The immune system is responsible for protecting the body against infections and helping control viruses that remain dormant after previous illnesses.

In healthy individuals, the immune system generally prevents the varicella-zoster virus from becoming active again. When immune defences weaken, the virus may have an opportunity to reactivate.

The stronger the immune response, the more likely the virus remains dormant.

Why Does Shingles Become More Common With Age?

Age is one of the strongest risk factors for shingles.

As we get older, the immune system naturally becomes less effective at controlling dormant infections. This process is a normal part of ageing.

Because of these changes, shingles becomes increasingly common in older adults. Older individuals may also be more likely to experience complications, including long-lasting nerve pain after the rash has healed.

This is one reason why shingles awareness and prompt treatment become increasingly important with age.

Medical Conditions That Can Increase Risk

Certain health conditions can affect the immune system and increase the likelihood of shingles.

Having one of these conditions does not mean you will definitely develop shingles. However, the risk may be higher because the body’s ability to control dormant viruses can be affected.

Medications That Affect the Immune System

Some medicines work by deliberately reducing immune system activity. These treatments can be important for managing a variety of medical conditions but may increase susceptibility to infections.

If you take medications that affect the immune system, you may be more vulnerable to shingles.

If you are unsure whether your medication affects your risk, our pharmacy team can provide advice.

Can Stress Trigger Shingles?

Many people report developing shingles during periods of significant stress.

While stress does not directly cause shingles, prolonged physical or emotional stress may affect the body’s ability to function at its best.

Although stress is unlikely to be the sole cause, it may contribute to conditions that allow the virus to reactivate.

Can You Prevent Shingles?

It is not always possible to prevent shingles completely. However, several measures may help reduce risk.

Why Early Treatment Matters

Even when shingles cannot be prevented, prompt treatment can make an important difference.

Antiviral medicines are most effective when started early after symptoms appear.

Under the NHS Pharmacy First service, eligible adults with suspected shingles may be assessed and supplied treatment where appropriate without needing a GP appointment.

What to Do Next

If you have developed a painful rash or are concerned about your risk of shingles, our pharmacy team is here to help.

We can assess symptoms, provide advice on treatment options, and determine whether Pharmacy First shingles treatment may be suitable for you.

Understanding how the immune system influences shingles risk can help you recognise symptoms early and seek treatment when it matters most.

If you would like advice about shingles or possible treatment options, contact our pharmacy team and we will be happy to help.