Shingles: why is it on the rise?

Cases of shingles are on the rise. In the UK, an estimated one in five people will develop shingles at one point in their life according to the British Association of Dermatologists (BAD).

But with the ‘baby boomers’ generation now reaching their 70s – the peak age to develop this viral reactivation of the chicken pox virus – healthcare professionals can expect to come across even more cases during the course of their day-to-day practice.

In England and Wales there are about 50,000 cases of shingles in people aged 70 or above every year, and it is estimated that about 50 of these cases result in death.¹

What is shingles?

Shingles or herpes zoster (HZ), sometimes known simply as zoster, is due to the chickenpox virus, varicella zoster. After chickenpox (varicella) has run its course, the virus retreats into the central nervous system in neurons of the dorsal root ganglia of the spinal cord, cranial nerve ganglia and autonomic ganglia. It lies dormant until the conditions are right. When the virus is reactivated, it travels along the nerve and causes lesions in the area supplied by the ganglia affected.

The incidence of HZ rises steeply from the age of 50. The lifetime risk of an attack is around 50% for those reaching the age of 85, according to the British Society for Geriatric Dermatology (BSGD).

The majority of children in the UK have chickenpox, and therefore could potentially develop HZ later in life.

Most shingles will occur “for no obvious reason, but they are more likely if the person is elderly, experiencing physical or emotional stress, taking treatments that suppress their immune system or has an illness that weakens their immune system, such as leukaemia lymphoma or HIV”, says Dr Sweta Rai of the British Association of Dermatologists (BAD).

Shingles “tends to be more common in the elderly because as the body ages, it has a harder time fighting off infection”, he says.

Shingles triggers

Nerve root pressure, radiotherapy at the level of the affected nerve root, injury, surgery, infection, or contact with someone with varicella or zoster may also precipitate an attack, the BSGD says.

Consultant dermatologist Dr Maggie Kirkup of the BSGD, says shingles is becoming more common because of the ageing of the population, survival of patients with immune deficiency disorders, chemotherapy, bone marrow and other transplants, and disease-modifying drugs for inflammatory disease which reduce immunity.

Shingles symptoms

Typically with shingles, prior to a blistering rash appearing, the most obvious symptom is pain felt in the area where the virus is reactivating.

Dr Rai says: “This pain is usually felt in one small area and can range from mild to severe. It can be felt differently from person-to-person, for example it could be a constant dull pain, a tingling, aching or a burning pain/sensation. “Whilst this is the most obvious symptom for those who get it, it is important to stress that not everyone will experience pain. Younger people often report only feeling an itching or mild burning sensation in the area that is affected.”

Patients with shingles generally feel unwell and may have fever and lymph node enlargement, advises Dr Kirkup. The eruption appears a day or so after the pain in a dermatomal distribution, which means that it affects the area supplied by the sensory nerve in which the virus has been latent, sometimes affecting adjacent dermatomes.

Most commonly this is seen on the trunk, so is limited to one area on one side of the body. The eruption consists of small papules which become vesicles then pustules before crusting and drying up.

A typical attack lasts for two to three weeks, commonly longer in older adults than younger, says Dr Kirkup. The eruption more commonly affects the cranial nerves in the elderly especially the ophthalmic division of the trigeminal nerve. It can cause blisters inside the mouth and ears and on the genital area, depending on the nerve or nerves involved.

An atypical symptom of HZ is known as zosta sine herpete, where pain occurs but no blisters form on the skin. This condition stems from infection and reactivation of the varicella-zoster virus (VZV) in the cranial nerve, spinal nerve, viscera, or autonomic nerve.²

Marian Nicholson, director of the Shingles Support Society, says the condition “is rarely diagnosed, but is often misinterpreted by patients to be a strained muscle, or something too minor to ask a doctor about”.

Variety of treatments for shingles

There are a variety of different treatments available, all of which have different functions. To shorten the outbreak and prevent post infective pain, antiviral drugs, such as Aciclovir tablets could well be prescribed. These tablets may shorten the duration, but work best when they are taken within the first three days of the onset of the outbreak. “This makes getting an early diagnosis from the GP very important,” says Dr Rai.

In some cases, postherpetic neuralgia occurs, which is when the pain caused by shingles persists long after the rash had cleared. Postherpetic neuralgia is particularly common in older patients. Taking antiviral drugs as early as possible can reduce the risk of this.

Painkillers could be prescribed to help a patient deal with the pain, such as special pain killers targeting the nerve pain, namely, amitriptyline or gabapentin, non-steroidal anti-inflammatories or counterirritant creams such as capsaicin, and even applying cool compresses may help.

If bacteria infect the area, antibiotic creams or tablets may be prescribed to the patient. “If shingles affects the eye, an ophthalmic doctor’s opinion should be sought, and they could prescribe eye drops,” says Dr Rai.

Shingles cannot be caught from someone who has it or from someone who has chickenpox. However, Dr Rai advises: “A person affected by shingles can give someone chickenpox if they haven’t had it before. A person with shingles is infectious when the first blister appears and remains infectious until the blisters have crusted over.”

He says those who have shingles “should avoid skin contact with those who have reduced immunity and have not previously had chickenpox. This is especially important for pregnant women”.

Ms Nicholson adds that spreading shingles is rare, because it can only be through direct contact with the skin, and shingles blisters will typically be hidden under clothing.

Who can get a shingles vaccine?

A shingles vaccine is available in the UK for people who are 70 to 79 years old, and is given as a single injection. “Those who are in this age group should contact their GP to ask for the vaccination. However, the shingles vaccine does not help a person who has already had the virus or has had postherpetic neuralgia,” says Dr Rai.

The vaccine is also “not suitable for people with a weakened immune system due to disease or medication and is not offered to those over 80 as it seems to be less effective in this age group”, says Dr Kirkup.

Research funded by Public Health England in 2017 shows that the vaccine is 62% effective against shingles.³ While Ms Nicholson says the vaccine is “brilliant news” for older patients, she says “many people tell us they’ve not heard of it”.

“So practitioners should be offering the vaccine routinely to every patient as soon as they hit 70,” she says.

Complications of shingles

Research shows the vaccine also prevents two thirds of cases of post-herpetic neuralgia (PHN) – a complication of shingles – in older people.⁴

PHN is a severe burning, throbbing or stabbing nerve pain which can last for several months or even years after the shingles rash has gone. Amitriptyline and gabapentin are the two main treatments prescribed for PHN. But the ‘antidepressant’ and ‘anticonvulsant’ labels can deter patients from taking them.

“The trouble is that patients can walk out of surgery with a script for an antidepressant thinking ‘I’m not depressed I’m in pain, so I’m not going to take this drug’. So they need a thorough briefing about why they should use an antidepressant treatment to ‘set up a pain block,’ from their practitioner,” says Ms Nicholson.

She adds that if a patient does develop PHN, practitioners need to make them “very aware that the starting dose for the drugs they are using is to start ‘setting up a pain block,’ that they are not therapeutic doses, and that they should be sure to come back for dose adjustment every few weeks”.

Complications with shingles can occur when the outbreak happens on the face. “This is because shingles could spread to the eye, leading to inflammation and ulceration. If left untreated, this can lead to scarring which can cause vision problems or blindness,” says Dr Rai.

Blisters that come up the side of the nose will alert a doctor of this risk and the patient would then be referred to an eye specialist, he advises.

Another potential complication comes from facial muscles becoming weak from the shingles outbreak, leading to temporary facial paralysis.

Shingles blisters can also become secondarily infected with bacteria and therefore “a viral and bacterial swab is important when assessing these patients so as to treat any coexisting bacterial infection whilst treating shingles,” says Dr Rai.

Caring for patients with shingles

Those caring for patients with shingles should encourage rest, provide pain relief if necessary, and avoid contact with the affected area where possible. Pregnant mothers or other at risk carers who are not immune should seek advice as they may need antiviral medication.

If someone has symptoms of shingles, they should be encouraged to see their GP as soon as they can so that the antiviral treatment prescribed has the best chance of working.

While cases of shingles may be on the rise, the vaccine is an opportunity to protect older people against this painful infection and to avoid long lasting problems. But, as Ms Nicholson stresses, there’s still a lack of awareness about its existence, “so it’s vital that practitioners inform eligible patients that it’s available on the NHS, and encourage them to get vaccinated.”

References

1. Oxford Vaccine Group. Shingles. Vaccine Knowledge Project. https://vk.ovg.ox.ac.uk/vk/shingles [Accessed 9 March 2021]
2. Zhou J, et al. Zoster sine herpete: a review. Korean J Pain 2020; 33(3): 208- 215. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7336347/ [Accessed 9 March 2021]
3. Amirthalingam G, et al. Evaluation of the effect of the herpes zoster vaccination programme 3 years after its introduction in England: a population-based study. The Lancet Public Health. December 21, 2017
4. Oxman MN, et al. A vaccine to prevent herpes zoster and postherpetic neuralgia in older adults. N Engl J Med 2005; 352(22): 2271- 84