Shingles is a painful rash and a consequence of the reactivation of the herpes-zoster virus decades after a first infection of chickenpox during childhood. It is more common among older people and immunocompromised patients.

In case you have shingles you can consult your doctor, who will possibly prescribe antivirals to reduce the duration of the infection and prevent complications and analgesics to control pain, after a clinical evaluation. If you are over 65 years old or have a weakened immune system, you can also ask your doctor if you are eligible for vaccination against shingles.

The role of varicella-zoster virus in shingles

Shingles (herpes zoster) is a viral infection caused by the varicella-zoster virus (VZV), a human herpes virus which is also the root cause of chickenpox (varicella). Chickenpox tends to be contracted during childhood and it is a common and easily contagious disease, therefore most of the kids will get infected at school or while playing at the playground.¹

Once you recover from chickenpox as a child, the virus remains dormant in some cranial and spinal nerves, until imbalances in the immune system linked to ageing or medical conditions lead to a reactivation of the virus that will move through the involved nerves all the way to the skin. Here the virus will start to make the skin more sensitive and painful, which will subsequently develop into the skin rash typical of shingles.

Having a weakened immune system and ageing are considered to be the main reasons behind the reactivation of the VZV which leads to the development of shingles.²

What triggers a shingles outbreak? 

Shingles is a late reactivation of the VZV decades after you first develop chickenpox at a younger age and therefore mainly affects older people. The causes have not been fully defined, however ageing and immunosuppression are two of the most common triggers of this disease.

On average, it has been shown that one in every three people will develop an infection with the herpes virus at some point throughout their lives and at an older age.

In a study conducted on 822 adults older than 16 years old, most of those who reported having shingles were around 63 years old. The association between ageing and shingles is that our immune system becomes weaker as we age.³

Other risk factors studied and potentially linked to a higher chance of developing shingles are:

• Female gender

Assigned females at birth are more likely to have shingles possibly also related to the physiological differences and hormonal changes, especially during menopause. The chance of contracting shingles was demonstrated to be 21% higher in women.³

• Non-White ethnic background

People of White ethnicity showed double the risk of having shingles compared to people with a Non-White background.³

• Frequent physical exercise 

Doing physical activity every day showed a 29% higher risk of contracting shingles compared to those who do not exercise at all. This link could be explained by moderate but frequently repeated exercise being potentially immunosuppressive.³

• Digestive disorders

People with digestive disorders are more likely at risk to develop shingles later on in life with a 51% higher chance compared to those who do not have any gastrointestinal condition.³

• Medical conditions 

People affected by conditions such as diabetes, urinary disorders, or respiratory disorders like Chronic obstructive pulmonary disease (COPD) are more likely to be affected by shingles. 

• Medications 

Some medications such as chemotherapy and steroids are immunosuppressive, making the patient more susceptible to reactivation of the viral activity.

Other lifestyle factors such as Body Mass Index (BMI) linked to being overweight or obese, smoking or drinking alcoholic beverages have not been related to a higher risk of triggering the VZV again to cause herpes zoster (shingles).

How are shingles diagnosed?

Physical examination

The skin rash in shingles appears usually on only one side of the body or face, which can also involve the eyes. The skin rash looks like a cluster of red blisters that will form a scab after about 7 days.

Medical history

A history of chickenpox combined with a current immunodeficiency caused by a medical condition, immunosuppressant treatments or ageing can help identify the skin rash as a sign of shingles.

Laboratory tests

Laboratory tests can be performed on specimens taken from the blisters of the shingles rash with a swab. The specimen is then analysed with different methods which are also used in the case of chickenpox which includes:

• Polymerase chain reaction (PCR)
• Direct fluorescent antibody (DFA) 
• Viral cultures 
• Antibodies serologic test

Shingles diagnosis: signs and symptoms 

Shingles is a viral infection that manifests as a painful and itchy skin rash that can appear on any part of your body and usually develops on only one side of the body.

Early symptoms 

These signs usually appear a few days before the skin rash starts to be visible on the skin:

• Tingling, itching, or pain felt in a specific part of the body, where the infection is developing
• Increased sensitivity to touch on the skin affected
• Headache 
• Fever, as an immune response to fight against the virus
• Upset stomach 

Common symptoms 

The main symptom is the appearance of an itchy and painful skin rash on usually only one side of the body and it can also affect the face and genitalia. The skin rash looks like the one caused by chickenpox and forms blisters that scab over after 7-10 days and heal within 2-4 weeks.

Fever, headache and general fatigue are also very common symptoms in addition to skin eruption.

What are common complications of shingles?

Postherpetic neuralgia 

Postherpetic neuralgia (PHN) is the prevalent complication of shingles. It is a long-term nerve painful feeling you feel in the area of your skin and body where you develop shingles. Pain can be intermittent or continuous and it is usually defined as a stabbing sensation that appears once the rash clears up.

Patients over 50 years old are more likely to develop PHN after being affected by shingles, and the risk increases as they age.

Secondary bacterial infections

The blisters caused by shingles can get infected, leading to a more serious condition that will need to be treated with antibiotics before it spreads to other parts of the body and organs such as the brain (causing encephalitis) and lungs (causing pneumonia).

Eye involvement

When shingles affect your face, it can also involve the eye and cause vision loss in more severe cases.

Infections, vision loss, and other more serious complications are usually seen in immunocompromised patients, who require prompt diagnosis and treatment before shingles turn into severe medical conditions.

What is the best treatment for shingles?

When you get shingles the best thing to do is to take rest and take medications to manage the symptoms to speed up the healing process and avoid more serious complications.

Antivirals are used to fight the varicella-zoster virus while painkillers and corticosteroids are used to ease pain and reduce severity of the acute symptoms.¹

Antiviral medications

Acyclovir, valacyclovir and famciclovir are the oral antivirals used to treat shingles by inhibiting the replication of the virus.

• Speed up the healing process
• Reduce the severity and duration of the infection
• Reduce risk of complications and PHN
• Well tolerated and generally safe
• Particularly recommended for patients over 50
• Ideally taken within the first 72 hours from the outbreak
• Valacyclovir and famciclovir are better absorbed and need to be taken less often 

Corticosteroids

Corticosteroids are anti-inflammatory medications that can be used alongside antivirals to reduce the severity and duration of the acute outbreak and related symptoms. Prednisone is the oral steroid of choice for shingles. However, corticosteroids should be used carefully and only in patients with more severe reactions to shingles, as these drugs can cause unpleasant side effects.

Painkillers 

Painkillers (or analgesics) are used to control pain caused by the skin rash in shingles. The nonsteroidal anti-inflammatory drugs (NSAIDs) are not really effective and therefore hardly used to treat shingles, but other medications that are also used to treat PHN are usually recommended and prescribed if necessary.¹ These include:

• Paracetamol (acetaminophen)
• Topical creams (lidocaine patches and capsaicin cream)

Other medications such as anticonvulsants, opioids and antidepressants could also be prescribed, if clinically suitable, in cases of severe neuropathic pain indicating typical complications of shingles.

Can I prevent shingles?

You can get a vaccine to prevent shingles and it is particularly recommended if you are older than 65 years old or if less than 65 but have a weakened immune system. Vaccination can help lower the chance of developing shingles and reduce the duration and complications of shingles if you do get infected. Shingrix and Zostavax are two vaccines available in the UK.

Summary

While shingles is a painful and potentially serious condition resulting from the reactivation of the varicella-zoster virus, prompt diagnosis and treatment can significantly mitigate its effects.

Antiviral medications, analgesics, and corticosteroids can be essential to reduce the duration and severity of the infection, while vaccination remains the most effective preventive measure, especially for older adults and those with a weakened immune system. 

Seeking medical advice when you recognize early symptoms will help you detect the infection in a timely manner, heal faster, and avoid possible progression into more serious complications.