Shingles (zoster)

Shingles is an acute, unilateral, self-limiting inflammatory disease of cerebral ganglia and the ganglia of posterior nerve roots and peripheral nerves in a segmented distribution, caused by Varicella Zoster virus (VZV) - the chicken pox virus.

Prodromal symptoms that herald HZ include pruritus, dysesthesia, and pain along the distribution of the involved dermatome

• this pre-eruptive pain may precede the rash by several days and may be mistaken for myocardial infarction, biliary or renal colic, pleurisy, dental pain, glaucoma, duodenal ulcer, or appendicitis, leading to misdiagnosis and potentially mistreatment
• in rare instances, the nerve pain is not accompanied by a skin eruption, a condition known as zoster sine herpete (1)

Herpes zoster (HZ) or shingles is a painful condition caused by reactivation of the Varicella Zoster virus (VZV) within the dorsal root or cranial nerve ganglia (1,2)

• the primary infection which causes varicella (chicken pox) results in
  • migration of the virus from skin lesions to spinal and cranial sensory ganglia where it becomes dormant
  • the development of VZV specific humoral and cell-mediated immunity (3)
    
    
• reactivation of the virus occurs when the cell mediated immunity wanes (1)
  
  
• following reactivation, the virus spreads thorough the affected sensory nerve, causing neuronal damage and reach the corresponding dermatome in the skin where a vesicular rash develops (3)

VZV (not HZ) can be transmitted to seronegative contact by an individual with HZ.

• it is less contagious than varicella - household transmission rate of HZ (to cause varicella) is 15% (3)

HZ usually occurs only once in life. Around 4-5% of patients may experience a recurrence (4).

Classic skin findings are grouped vesicles on a red base in a unilateral, dermatomal distribution.

• however, the lesions of HZ progress through stages, beginning as red macules and papules that, in the course of 7 to 10 days, evolve into vesicles and form pustules and crusts. Complete healing may take more than 4 weeks (5)
  • key clinical feature of shingles is a dermatomal eruption of vesicles often preceded by pain and paraesthesia by several days. Erythema precedes the development of vesicles. The vesicles may become pustular 2-3 days following eruption. A tender lymphadenopathy (local) is common in the early stages of the rash. There is increased itching and burning. The affected area may remain depigmented and often it is hypoalgesic.
• sites affected:
  • most commonly, the lower thoracic region
  • ophthalmic division of the trigeminal nerve
  • occasionally motor nerves, causing paralysis - for example facial paralysis in Ramsay Hunt syndrome, or urinary retention

Disseminated HZ occurs primarily in immunocompromised patients; it usually presents with a dermatomal eruption followed by dissemination but may also present with a diffuse varicella-like eruption (5)

Complications are seen in 13-40% of patients.

• postherpetic neuralgia (PHN) is the commonest complication
  • incidence of PHN is generally estimated to be between 10 and 20% of cases of HZ (up to 30% in the elderly)
    • 80% of all PHN cases are reported in patients over the age of 50 years (4)

Click here for example images of this condition

Herpes zoster lesions contain high concentrations of VZV, which can be spread by contact and by the airborne route and which can cause primary varicella in exposed, susceptible persons. Less contagious than primary varicella, HZ is only contagious after the rash appears and until the lesions crust. Risk of transmission is reduced further if lesions are covered

• N.B. Shingles is not as infectious as chicken pox; but people who have not had chicken pox may get chicken pox as a result of contact with a person with shingles.

Key points:

• Shingles:
  • treat if >50 years (post herpatic neuralgia rare if <50 years) and within 72 hours of rash or if 1 of the following:
    • active ophthalmic;
    • Ramsey Hunt; eczema;
    • non-truncal involvement;
    • moderate or severe pain;
    • moderate or severe rash
• shingles treatment if not within 72 hours:
  • consider starting antiviral drug up to 1 week after rash onset if
    • high risk of severe shingles or continued vesicle formation;
    • older age;
    • immunocompromised;
    • or severe pain

Changes to the shingles vaccination programme in the England from 1 September 2023 (6)

Change of vaccine:

Shingrix® will replace Zostavax® for the whole shingles programme.

Shingrix® will require a 2-dose schedule for all cohorts. The dosing interval will differ for immunocompromised vs. immunocompetent patients.

Shingrix® should be offered to all people reaching eligible age on or after 1 September 2023. Those cohorts previously eligible for Zostavax® who are under 80 years of age, should continue to be offered Zostavax® until central stocks deplete, after which they should be offered Shingrix®.

Individuals who have received Zostavax® previously should not be revaccinated with Shingrix®.

It is safe to administer Shingrix® with other vaccines.

Patients can be immunised with the shingles vaccine at any point in the year as soon as they reach eligible age.

Changes to eligibility:

Immunocompromised cohort:

From September 2021, Shingrix® was available to immunocompromised individuals aged 70 to 79 years, who are contraindicated to receive Zostavax®, as part of the NHS shingles vaccination programme.

Since 1 September 2023, this eligibility has been expanded to all immunocompromised individuals aged 50 years and over (with no upper age limit).

Immunocompromised individuals who have already received 2 doses of Shingrix® do not need re-vaccination.

Immunocompromised individuals are the highest priority for vaccination given their risk of severe disease. The programme aims to catch up all immunocompromised individuals aged 50 years and over in the first year of implementation.

The second dose of Shingrix® should be given 8 weeks to 6 months after the first dose for this cohort.

Immunocompetent cohort:

The age of eligibility for immunocompetent individuals has reduced from 70 to 60 years old for the routine cohort, in a phased implementation over a 10 year period.

The routine offer will move from 70 to 60 years of age in 2 stages over a 10 year period:

Stage 1 (1 September 2023 to 31 August 2028):

Shingrix® will be offered to those turning 70 and 65 years on or after 1 September 2023

Zostavax® will be offered to persons aged between 70 to 79 that were eligible for the vaccination programme before 1 September 2023. Once all stocks of Zostavax® are exhausted, these individuals can be offered Shingrix® if they have not previously been given a shingles vaccine.

Stage 2 (1 September 2028 to 31 August 2033):

Shingrix® will be offered to those turning 65 and 60 years of age.

From 1 September 2033 and thereafter, Shingrix® will be offered routinely at age 60 years.

Those who have been previously eligible (in stages 1 and 2) will remain eligible until their 80th birthday.

References

1. Werner RN et al. European consensus-based (S2k) Guideline on the Management of Herpes Zoster - guided by the European Dermatology Forum (EDF) in cooperation with the European Academy of Dermatology and Venereology (EADV), Part 1: Diagnosis. J Eur Acad Dermatol Venereol. 2017;31(1):9-19.
2. Fashner J, Bell AL. Herpes zoster and postherpetic neuralgia: prevention and management. Am Fam Physician. 2011;83(12):1432-7.
3. Johnson RW, Alvarez-Pasquin MJ, Bijl M, et al. Herpes zoster epidemiology, management, and disease and economic burden in Europe: a multidisciplinary perspective. Ther Adv Vaccines. 2015;3(4):109-20.
4. Armando S, Nicoletta V, Sara P, Matilde G, Silvia L, et al. Herpes Zoster: New Preventive Perspectives. J Dermatolog Clin Res. 2015;3(1):1042
5. Homler H.Herpes zoster: query and concern. Mayo Clin Proc. 2009 Jul;84(7):663; author reply 663-4.
6. Shingles vaccination programme changes from September 2023. ; letter/introduction of shingrix vaccine for the whole programme and expansion of eligible cohorts letter. (Online)