What is shingles?

Shingles is a viral infection that causes a painful rash.^1,2 Anyone who’s ever had chickenpox can develop shingles, and it is estimated that around 1 in 2 people who have had chickenpox will develop shingles at some point in their life.³

The risk of developing shingles increases with age. This may be linked to the declining strength and efficacy of our immune systems as we age.² 

Understanding shingles

The varicella-zoster virus causes both chickenpox and shingles.² 

After you’ve recovered from chickenpox, the virus remains inactive in your body for the rest of your life. It remains in the neural ganglia - nerves in your peripheral nervous system.⁴ The majority of the time, the virus stays inactive and doesn’t result in any problems. However, in around 10-20% of cases, the virus reactivates and travels along your nerve pathways to your skin, resulting in shingles!^2,4 

The varicella-zoster virus belongs to the group of viruses called herpes viruses, which also cause cold sores and genital herpes. However, cold sores and genital herpes are caused by different viruses.² 

Symptoms of shingles 

The first symptoms of shingles are usually a tingling/painful feeling on your skin and feeling generally unwell, with symptoms such as a headache.¹ 

A rash will appear a few days later, manifesting as blotches on your skin. Typically, a shingles rash forms on your chest or tummy, but can appear anywhere on your body including your face, eyes or genitals.¹ However, the characteristic feature of a shingles rash is that it occurs only on one side of your body.¹ Therefore, it is unlikely to be shingles if you have a rash on the left and right side of your body.¹ However, it is important to remember that you can have shingles without having a rash. 

The blotches become itchy blisters that often ooze fluid, before drying out and scabbing.² The rash can take up to 4 weeks to heal, and the skin remains painful and sensitive after the rash has gone.

What are the risk factors for shingles?

• Age: shingles is more common with increasing age, and the risk of severe complications rises in elderly individuals²
• History of chickenpox: after infection, the chickenpox virus remains dormant in your body for many years and can later reactivate and cause shingles²
• Weakened immune system: allows the virus to reactivate more easily²

The role of the immune system in shingles

Weakened immune system

When your immune system is weakened, e.g. by cancer treatments (such as radiation or chemotherapy) or diseases such as HIV/AIDS, your risk of developing shingles - and of it developing into a more severe infection - increases.^2,3

This is because your immune system is responsible for preventing the reactivation of the varicella-zoster virus. A strong immune system is able to limit disease severity and to avoid reactivation, by combining mechanisms to detect and respond to the virus. These mechanisms include:⁵

• Cytotoxic T-cells: T-cells are important in fighting off the initial infection. They reduce the viral load (number of viral particles present) and recognise and eliminate viruses if they try to reactivate again later on
• Memory T-cells: memory T-cells persist in the body after the first infection and quickly respond if there are any signs of reactivation, helping to re-suppress the virus
• Interferons and cytokines: These chemicals are vital to the antiviral defence and preventing the replication of the virus
• Natural killer (NK) cells: these cells target and eliminate cells which have been invaded by the virus
• Antibodies: antibodies are produced by B-cells during the initial infection. They have important roles, both during the initial infection and in defending against any reactivations
• Immune surveillance: the immune system’s components constantly patrol the body and detect invading microorganisms, ensuring any signs of viral reactivation are recognised and addressed

Given its importance in recognising and fighting infections, if your immune system becomes weakened (even just by a cold, extreme stress, or tiredness) viruses may be able to quickly reactivate and cause problems.³

The role of stress in shingles

The definition of stress is a state of worry or mental tension caused by a difficult situation.^6,7 Stress is a natural human response, and in some situations, a little bit of stress can be beneficial. However, excessive stress can cause physical and mental health problems.⁷

There are different types of stress:⁸

• Acute stress: when you’re in a situation of sudden danger, and the stress response lasts for a short period of time, e.g. sitting an exam
• Chronic stress: long-term stress, e.g. a difficult job, or a chronic illness
• Traumatic stress: with a life-threatening event, such as a natural disaster or if you are assaulted 

Generally, short-term stress is protective and helpful, whereas long-term stress is harmful for your body and mind.⁹ 

How does stress affect your body?

Hormonal changes

In response to any of these types of stress, your body releases cortisol. Cortisol is a steroid hormone that is produced and released by your adrenal glands.⁸ Cortisol coordinates multiple different functions in your body, which together tell your body how to respond to the situation that you are in. 

The roles of cortisol include:⁸

• Regulating your body’s stress response
• Helping with metabolism (using fats, proteins, and carbohydrates)
• Suppressing inflammation 
• Regulating blood pressure 
• Regulating blood sugar
• Controlling your sleep-wake cycle

Your body is constantly trying to maintain a constant level of cortisol levels, as significantly increased or decreased levels are both harmful. 

Physical and psychological effects of stress

Stress can cause significant anxiety and irritability, and can considerably affect your mental health.⁷ Stress can cause other problems too, such as:

• Difficulty concentrating
• Headaches
• Body pains
• Trouble sleeping
• Altered appetite (either increased or decreased appetite)

Stress and immune function

In the short-term (i.e. lasting minutes to hours), stress causes the body to produce and release bursts of cortisol and boosts your immunity by limiting levels of inflammation and enhancing the immune system.^8,9

However, constant stress (and, by extension, constantly elevated cortisol levels) can cause inflammation and weaken the immune system - potentially causing it to become dysregulated or even suppressed.^8,9

Stress-related immune dysfunction can manifest as delayed wound healing, increased susceptibility to infection, and the reactivation of inactive viruses - which can directly affect your susceptibility to shingles.⁹

Stress and shingles

Studies have shown that high levels of stress are linked to an increased risk of shingles.¹⁰ Additionally, many patients with shingles report that their disease occurred after a stressful period or a traumatic event. 

Stress reduction techniques

Where possible, it is beneficial to reduce long-term/chronic stress - in terms of both your susceptibility to shingles and your general health and well-being. 

Stress reduction techniques work differently for different people, but here are some examples of techniques you could try to reduce your stress:

• Mindfulness and meditation 
• Physical exercise 
• Adequate sleep
• Balanced diet
• Talking to a counsellor, therapist, or trusted loved ones

When to seek medical advice 

The treatment of shingles largely depends on the severity of your symptoms, and whether you’re at risk of complications.¹ A mild rash may not need any treatment. 

Early treatment may shorten a shingles infection and reduce the chances of complications.² One relatively common complication is postherpetic neuralgia, which refers to the persistence of shingles pain for a long time after your blisters have cleared.² 

Medical Interventions 

• Antiviral medications: antiviral tablets taken within 3 days of your rash appearing can speed your recovery from a shingles infection if you have a weakened immune system, or if your rash is more severe or affects parts of your body other than your chest, tummy, and back¹
• Pain management strategies: painkillers, steroid tablets, or medications to help with nerve pain. Even a cool compress (such as frozen vegetables wrapped in a towel) can help to ease pain¹ 

Summary 

Shingles is a relatively common disease that can affect anyone who has had chickenpox. Generally, you will be able to get better on your own and without medical intervention. However, if you’re at all worried about your symptoms or believe you may have a compromised immune system, you should contact a health professional. If you are receiving any treatment for cancer, have HIV/AIDS, or are of older age, it is important to contact a health professional.

Since the immune system has an important role in preventing the reactivation of the Herpes-Zoster virus, any condition that causes suppression of the immune system, including chronic stress, increases your risk of developing shingles. This means that trying to reduce your levels of stress is beneficial to reduce your risk of developing shingles - as well as offering many other mental and physical benefits. 

If you are struggling with stress and feel it is impacting your wellbeing, it is important to talk to people you trust and contact a health professional or a counselor.