What is the management of a patient presenting with zoster, including contact precautions and vaccine recommendations?

Management of Herpes Zoster

For a patient presenting with herpes zoster, initiate oral antiviral therapy with valacyclovir 1000 mg three times daily or acyclovir 800 mg five times daily for 7 days, ideally within 72 hours of rash onset, continue treatment until all lesions have completely scabbed, implement contact precautions until all lesions crust, and administer the recombinant zoster vaccine (Shingrix) at least 2 months after acute symptoms resolve. 1, 2, 3

Antiviral Treatment

First-Line Therapy for Immunocompetent Patients

• Valacyclovir 1000 mg orally three times daily for 7 days is the preferred first-line treatment due to superior bioavailability (3-5 fold higher than acyclovir), less frequent dosing, and accelerated resolution of zoster-associated pain compared to acyclovir. 2, 4, 5

• Acyclovir 800 mg orally five times daily for 7-10 days is an effective alternative if valacyclovir is unavailable, though it requires more frequent dosing and may be less effective for pain reduction. 3, 1

• Treatment must be initiated within 72 hours of rash onset for optimal efficacy in reducing acute pain, accelerating lesion healing, and preventing postherpetic neuralgia, though treatment started later than 72 hours may still provide benefit. 1, 3

• Continue antiviral therapy until all lesions have completely scabbed, not just for an arbitrary 7-day period—this is the key clinical endpoint. 1

Treatment for Immunocompromised Patients

• Intravenous acyclovir 10 mg/kg every 8 hours is mandatory for immunocompromised patients with herpes zoster, continuing for a minimum of 7-10 days until all lesions have completely scabbed. 1

• Consider temporary reduction or discontinuation of immunosuppressive medications in cases of disseminated or invasive herpes zoster if clinically feasible. 1

• Immunocompromised patients may require extended treatment duration beyond 7-10 days, as lesions develop over longer periods (7-14 days) and heal more slowly. 1

Special Situations Requiring IV Therapy

• Disseminated herpes zoster (multi-dermatomal involvement or visceral disease) 1
• Complicated facial zoster with suspected CNS involvement 1
• Severe ophthalmic disease 1
• Patients unable to tolerate oral medications 1

Renal Dose Adjustments

For patients with renal impairment, mandatory dose adjustments are required to prevent acute renal failure:

• Valacyclovir dosing by creatinine clearance: 2

  • CrCl 30-49 mL/min: 1000 mg every 12 hours
  • CrCl 10-29 mL/min: 1000 mg every 24 hours
  • CrCl <10 mL/min: 500 mg every 24 hours

• Acyclovir dosing by creatinine clearance: 3

  • CrCl 10-25 mL/min: 800 mg every 8 hours
  • CrCl <10 mL/min: 800 mg every 12 hours

• Monitor renal function at initiation and once or twice weekly during treatment, especially with IV acyclovir. 1

Infection Control and Contact Precautions

Standard Precautions for All Patients

• Patients with herpes zoster must avoid contact with susceptible individuals until all lesions have crusted, as lesions are contagious to individuals who have not had chickenpox or vaccination. 1, 6

• Cover lesions with clothing or dressings to minimize transmission risk during the contagious period. 1

• Healthcare workers with herpes zoster should be excluded from duty until all lesions dry and crust. 1

Enhanced Precautions for Specific Situations

• For disseminated zoster (lesions in >3 dermatomes), implement both airborne and contact precautions in addition to standard precautions. 7

• For immunocompromised patients with herpes zoster, implement airborne and contact precautions due to higher risk of dissemination. 7

• Physical separation of at least 6 feet from other patients is recommended for patients with active herpes zoster in healthcare settings. 7

Post-Exposure Prophylaxis

• Varicella zoster immune globulin (VZIG) should be administered within 96 hours of exposure to varicella-susceptible patients (those without history of chickenpox or vaccination, or who are seronegative for VZV). 1

• If VZIG is not available or more than 96 hours have passed, administer a 7-day course of oral acyclovir beginning 7-10 days after varicella exposure. 1

Vaccination Recommendations

Timing After Acute Episode

• Administer the recombinant zoster vaccine (Shingrix) at least 2 months after acute symptoms have completely resolved, as this is the minimum documented interval between herpes zoster episodes and allows for immune system recovery. 8

• Do not delay vaccination beyond the minimum 2-month period, as the cumulative recurrence risk is 2.5% at 2 years, 6.6% at 6 years, and 10.3% at 10 years. 8

• Having had herpes zoster does not provide reliable protection against future recurrences, making vaccination after an outbreak particularly important. 8

Vaccine Schedule and Administration

• Shingrix is administered as a two-dose series: 6

  • First dose: Immediately after the 2-month waiting period
  • Second dose: 2-6 months after the first dose for immunocompetent patients
  • Second dose: 1-2 months after the first dose for immunocompromised patients

• The minimum interval between doses is 4 weeks; if administered earlier, the dose should be repeated. 6

• Shingrix is administered intramuscularly (IM). 6

Vaccine Efficacy and Safety

• Shingrix demonstrates 97.2% efficacy in preventing herpes zoster in adults aged 50 years and older, with protection persisting for at least 8 years with minimal waning (maintaining efficacy above 83.3%). 6

• Common side effects include injection-site reactions (pain, redness, swelling) in 9.5% and systemic symptoms in 11.4%, but no serious safety concerns have been identified. 6

• Shingrix is safe for immunocompromised patients, unlike the live-attenuated Zostavax which is contraindicated in this population. 6

Special Populations

• For patients who previously received Zostavax, administer Shingrix at least 2 months after the last Zostavax dose, as Zostavax efficacy drops to only 14.1% by year 10. 6

• For immunocompromised adults aged ≥18 years, use the shorter 1-2 month schedule between doses. 6

• For patients on low-dose glucocorticoids (<10 mg/day prednisone equivalent), Shingrix can be safely administered without adversely impacting vaccine response. 6

Common Pitfalls and Caveats

Treatment Errors to Avoid

• Never use topical antivirals for shingles, as they are substantially less effective than systemic therapy. 1

• Do not discontinue antiviral therapy at exactly 7 days if lesions are still forming or have not completely scabbed—short-course therapy designed for genital herpes is inadequate for VZV infection. 1

• Do not apply corticosteroid creams to active shingles lesions, as this can increase the risk of severe disease and dissemination, particularly in immunocompromised patients. 1

• Avoid unnecessary prolonged suppressive therapy in immunocompromised patients to prevent development of acyclovir resistance. 1

Vaccination Errors to Avoid

• Never use live-attenuated Zostavax in immunocompromised patients or those about to start immunosuppressive therapy—only Shingrix is appropriate. 6, 8

• Do not confuse the 2-month waiting period after herpes zoster with the 2-6 month interval between vaccine doses—these are separate timeframes. 8

• Do not delay vaccination beyond the minimum 2-month period after acute episode, as this unnecessarily increases recurrence risk. 8

Monitoring for Complications

• If lesions fail to begin resolving within 7-10 days, suspect acyclovir resistance and obtain viral culture with susceptibility testing. 1

• For confirmed acyclovir resistance, switch to foscarnet 40 mg/kg IV every 8 hours until clinical resolution. 1

• Monitor for thrombotic thrombocytopenic purpura/hemolytic uremic syndrome in immunocompromised patients receiving high-dose therapy. 1