Shingles is an unpleasant condition associated with a rash which can be painful. It differs from other rashes in that it appears at a particular site and does not spread to other parts of the body. Although it can affect people of any age, it is most common in those over 50 years and increases in prevalence among older adults, affecting approximately 1 in 4 people at some time in their lives (Tidy, 2020). Given the frequency of its occurrence, general practice nurses and advanced nurse practitioners will encounter patients either with symptoms, or asking for advice and guidance on managing their illness. This article, therefore, hopes to give an overview of the recognition, treatment, management and prevention of shingles, with the aim of improving outcomes and quality of life for those affected.
Prevalence rates
The overall incidence in adults is estimated to be 1.85 to 3.9 cases per 1000 population (National Institute for Health and Care Excellence (NICE), 2021), with an increasing occurrence in older adults and an estimated 790 to 880 cases per 100 000 in those aged 70-79 years of age in England and Wales (Harding, 2016). Shingles in children is less common, and most healthy children will not develop shingles until well in to adulthood. Statistics suggest the rate of shingles in children to be 0.74 per 1000 people in children below the age of 10 (GP Notebook, 2021). There may be no cause for the illness in a child, but a few possible trigger factors have been identified and these are shown in Table 1.
Table 1. Possible trigger factors associated with shingles in children
| Possible trigger factor | Additional information |
|---|---|
| Immunosuppression | Children with a malignancy, or those undergoing treatment for cancer, or children who have undergone organ transplantation |
| Chronic diseases | Chronic diseases such as rheumatoid arthritis and diabetes, which reduce the body's immune response to infection |
| Exposure to the virus during pregnancy | Maternal infection during pregnancy increases the risk of contracting herpes zoster in early childhood |
Pathophysiology
Anyone that has previously had chickenpox (usually in childhood) may subsequently develop shingles, because the disease occurs as a result of reactivation of the chicken pox virus at a site where the virus has resided in a dormant state following the initial infection. Once the initial infection has resolved, the virus settles in dorsal root ganglia, often for a prolonged period (years or decades) until reactivation occurs (Janniger, 2021). During the dormant phase, the body's immune system manages to successfully suppress replication of the virus and is able to do this for a number of years. In many cases, the reason for reactivation is unknown; however, the following factors may increase the likelihood of this occurring (Tidy, 2020):
- Stress
- Illness
- Aging of the immune system and reduced efficiency
- Immunosuppression (AIDs, HIV, chemotherapy and oral steroids)
- Weakened immune system (recent bone marrow transplant or organ transplant).
When the virus reactivates it multiplies and moves along the nerve fibres to the area of skin supplied by those particular nerves; shingles then appears in this area (British Association of Dermatologists, 2020). Figure 1 shows the dermatomes. Table 2 shows common sites for the rash to appear.
Table 2. Dermatomal distribution of shingles
| Dermatome affected | Percentage of cases |
|---|---|
| Thoracic | 53% |
| Cervical | 20% |
| Trigeminal including ophthalmic | 15% |
| Lumbosacral | 11% |
Signs and symptoms
The disease course is usually described as occurring in three phases (Thomas and Jennings, 2014):
- Prodrome (early symptoms stage) - 1-4 days prior to rash appearing
- Infectious rash (acute stage) - 7-10 days duration
- Resolution (healing stage) - 2-4 weeks duration.
Prodrome
During this phase the patient experiences pain in the affected dermatome, which can be intermittent or constant, and may be described as burning, stabbing or throbbing (NICE, 2021). In severe cases the pain may interfere with the patient's normal sleep pattern. In addition, the patient may complain of malaise, headache, and/or fever (Saguil et al, 2017).
Infectious stage
Within 2 to 3 days (rarely 7 days) the rash appears, initially as a maculopapular rash which progresses to clusters of vesicles, which continue to develop over a 3-5-day period (NICE, 2021). The vesicles then burst and crust over, which usually takes 7-10 days (NICE, 2021).
Resolution
Once crusting of the vesicles has occurred the patient is no longer infectious, but the crusty appearance of the rash may persist for a further 2 weeks (Thomas and Jennings, 2014). In older people, or the immunocompromised, the rash may have an atypical appearance and be more severe or take longer to resolve (NICE, 2021). Table 3 has more information on patients at risk of a more severe illness.
Table 3. Patients at risk of more severe illness
| Risk factor | Additional information |
|---|---|
| Patients taking high dose steroids | Patients taking 40 mg of oral prednisolone for more than 1 week in the previous 3 months |
| Patients on oral steroids | Lower doses but in combination with other immunosuppressant medication (eg azathioprine) |
| Patients taking anti-arthritic medications | These can affect the bone marrow |
| Patients having chemotherapy or radiotherapy | In the previous 6 months prior to contracting the illness |
| Impaired immunity | Includes the immunosuppressed (eg HIV infection or those who have had a bone marrow transplant) |
Is shingles contagious?
Shingles does not spread from person to person, but it is possible for someone to develop chicken pox if they have not previously had this disease. However, this is less likely if the rash is in an area that would normally be covered, such as on the abdomen. Spread can only occur if the rash is weeping. Guidance generally advises avoidance of the immunocompromised, pregnant women and babies less than 1 month old (NHS, 2021a). Pregnant women who develop chicken pox following shingles contact are at risk of a severe illness and serious effects, including varicella pneumonia, hepatitis and encephalitis and, rarely, death (Royal College of Obstetricians and Gynaecologists (RCOG), 2021). The effect on the unborn baby depends on the stage of pregnancy the woman is at prior to developing the disease (see Table 4 for more information).
Table 4. Effect on the baby of catching chicken pox in pregnancy
| Stage of pregnancy | Effect on the baby |
|---|---|
| Before 28 weeks of pregnancy | 1 in 100 babies may develop problems with the legs, arms, eyes, bladder, bowel or brain. Mother will be referred to a specialist for scans and further investigations if deemed necessary |
| Between 28 and 36 weeks of pregnancy | The virus will remain in the baby's body but will not cause symptoms. Reactivation may occur causing shingles in the first few years of life |
| After 36 weeks of pregnancy | The baby is at greatest risk of developing chicken pox during this period. If baby is born within 7 days of mother developing the rash, or within the first week after giving birth, the baby may get severe chickenpox |
Diagnosis
Diagnosis is made on the history and clinical findings on examination of the patient and there are no tests to aid diagnosis. Figure 2 shows an example of the shingles rash. The rash usually appears on one side of the body only. A rash on both sides of the body is unlikely to be shingles (NHS, 2021a). The rash develops into itchy blisters which look similar to chickenpox. The rash may be atypical in certain groups of people, for example older people and immunocompromised people (NICE, 2021). Differential diagnoses may include herpes simplex virus infection and contact dermatitis (NICE, 2021).
Treatment and management
Treatment with oral antiviral drugs decreases the severity and duration of the illness and is thought to decrease the risk of serious complications in immunocompromised patients (Kaye, 2021). In order for the treatment to be effective guidance advises that it is commenced within 72 hours of the development of the rash (Kaye, 2021) or up to 1 week after onset for those at high risk of complications. Antiviral treatment may not be offered to all patients who develop the disease. Table 5 gives information on those who may benefit.
Table 5. Patients most likely to benefit from antiviral treatment
| Moderate or severe pain |
| Immunosuppressed patients (see Table 3) |
| Patients with a rash affecting the eye or ear |
| Shingles affecting other parts of the body apart from the trunk, such as the arms, legs, genital area or the neck |
| Moderate or severe rash |
Options available are (NICE, 2021a):
- Aciclovir: 800 mg five times a day for 7 days (continue for a further 2 days after crusting of the rash in the immunocompromised)
- Famociclovir: 500 mg three times daily for 10 days (continue for a further 2 days after crusting of the rash in the immunocompromised)
- Valaciclovir: 1000 mg three times daily for 7 days (continue for a further 2 days after crusting of the rash in the immunocompromised).
Complications
Post-herpetic neuralgia, the most common complication of herpes zoster, is defined as pain in a dermatomal distribution that is sustained for at least 90 days after the rash (Perry, 2016; Saguil et al, 2017). Shingles which affects the ophthalmic nerve can be particularly unpleasant and may be potentially serious, resulting in severe and lasting pain, particularly in elderly patients (Opstelten and Zaal, 2005). Conjunctivitis is seen in nearly all ophthalmic zoster patients. More severe disorders include keratitis, uveitis and optic neuritis of the affected eye (Opstelten and Zaal, 2005). Some of the rarer complications are shown in Table 6.
Table 6. Less common complications of shingles
| Complication | Additional information |
|---|---|
| Ramsay Hunt syndrome | Peripheral facial neuropathy |
| Skin discolouration | Loss of pigment or scarring at the site of the rash |
| Muscle weakness | If the nerve affected supplies muscles, weakness of the affected muscle may persist |
| Inflammation | Rarely inflammation of the lungs, liver, brain, spinal cord, or protective membranes that surround the brain and spinal cord |
Prognosis
The outcome for the majority is favourable and both adults and children can return to work or school once the blisters have dried up, or earlier if the rash is covered and they feel well enough (Tidy, 2020). Shingles is rarely life threatening, but severe complications (usually in older adults) result in 1 in every 1000 in those over the age of 70 having a fatal outcome (NHS Inform, 2021).
Prevention
A shingles vaccination programme commenced in the UK in 2013, and has been successful in significantly reducing the chances of developing the disease, or reducing its duration and severity in those affected despite vaccination (UK Health Security Agency, 2021a). The vaccine is currently given to adults aged between 70-79 years, but is not offered to those aged 80 years of age and older because its effectiveness is diminished in this age group (NHS, 2021b). Younger adults are not included because the risk of developing the illness if thought to be less in this age group. The vaccine is given by intramuscular injection into the deltoid muscle and there are currently two vaccines in use. These are (UK Health Security Agency, 2021b):
- Zostavax: given as a single vaccination, it is a live vaccine and most patients will be given this vaccine
- Shingrix: given as two injections 2 months apart, this is given only to patients who have a sensitivity to any of the constituents in Zostavax, or those whose immunity is impaired (eg, those with leukaemia, HIV or any condition affecting the bone marrow).
The vaccine can be given to patients who have already had shingles and is thought to significantly reduce the chance of developing the disease again, or for the few who still develop symptoms these will be milder and of shorter duration (UK Health Security Agency, 2021b).
Conclusion
Shingles is a relatively common condition, more frequently seen in older adults. Although usually a self-limiting condition, for a few patients its effects are more severe and long lasting. Pain (post-herpetic neuralgia) is likely to persist after resolution of the disease itself. Serious complications are rare and the development of the vaccine for older adults has reduced the likelihood of developing the disease or its severity in those unfortunate enough to do so despite vaccination. Practice nurses have a major role to play in encouraging patients to take up the offer of vaccination when it is available to them.
KEY POINTS:
- Shingles can affect any age group, but is more common in older adults
- Antiviral treatment may be beneficial in some cases. If prescribed it can reduce disease severity and duration of symptoms
- A vaccine is available for eligible patients
CPD reflective practice:
- Can you explain the pathophysiology of shingles?
- What are the key signs and symptoms of the condition?
- Who is eligible for a shingles vaccine and how could you increase uptake among your patients?