Shingles and Immunity: What You Need to Know

Shingles, a painful rash caused by the reactivation of the varicella-zoster virus (VZV), can be a concerning health issue. Understanding how shingles relates to your immune status, particularly if you’ve had chickenpox or received a varicella vaccine, is crucial for prevention and management. Here’s a comprehensive glance at shingles, vaccination, and immunity.

What is Shingles?

Shingles is caused by the varicella-zoster virus, the same virus that causes chickenpox. After you recover from chickenpox, the virus remains dormant in your nerve cells. Shingles occurs when this virus reactivates later in life. It typically presents as a painful rash with blisters on one side of the body, often on the torso, but can appear on other areas like the face or neck.

Is Shingles Contagious?

Even as shingles itself isn’t directly contagious, the virus can be spread to individuals who have never had chickenpox or the chickenpox vaccine through direct contact with the fluid from the blisters. Transmission is possible until the rash develops scabs, typically within 7 to 10 days [1]. If someone has already had chickenpox, their risk of contracting shingles from someone with the rash is very low.

Shingles Vaccination: Why It’s Important Even with Prior Immunity

Even if you’ve had chickenpox or received the varicella vaccine, you should still get vaccinated against shingles. Here’s why:

• Latent Virus: The varicella-zoster virus remains latent in the dorsal root ganglia, meaning it can reactivate even with existing immunity [2].
• Recombinant Zoster Vaccine (Shingrix): Shingrix is recommended for all adults aged 50 and older, regardless of their prior chickenpox history or varicella antibody status [2].
• High Efficacy: Shingrix is highly effective, preventing herpes zoster in 97.2% of cases, with protection lasting at least 8 years [2].

Who Should Get the Shingles Vaccine?

The Centers for Disease Control and Prevention (CDC) recommends shingles vaccination for:

• Healthy Adults: Adults 50 years and older should receive two doses of Shingrix, 2 to 6 months apart [3].
• Immunocompromised Patients: Individuals 18 years and older undergoing immunosuppressive therapy (including those on JAK inhibitors, biologics, or immunomodulators) should also receive Shingrix, with a shortened interval of 1-2 months between doses (minimum 4 weeks) [2]. Shingrix is a non-live vaccine and is safe for immunocompromised individuals [2].
• Patients with Specific Conditions: Individuals with inflammatory bowel disease (IBD) aged 50 and older on immunomodulators or advanced therapies, and those starting JAK inhibitors at any age, should receive the Shingrix vaccine [2].

Understanding Varicella IgG

A positive varicella IgG result indicates prior exposure to the varicella-zoster virus, either through natural infection (chickenpox) or vaccination. Still, this does not eliminate the need for shingles vaccination. The virus remains latent and can reactivate, causing shingles, even with existing antibodies [2].

Laboratory Testing for VZV

Lab testing is available for varicella-zoster virus, the cause of both chickenpox and shingles [3]. Information on specimen collection and testing can be found on the CDC website.

Key Takeaways

• Shingles is caused by the reactivation of the varicella-zoster virus.
• While not directly contagious, shingles can spread to those who haven’t had chickenpox or the vaccine.
• Vaccination with Shingrix is recommended for all adults 50 and older, regardless of prior immunity.
• Shingrix is highly effective and safe, even for immunocompromised individuals.