Will the Shingrix (zoster vaccine) vaccine cause a positive varicella zoster test result?

Shingrix Vaccine and Varicella Zoster Testing

The Shingrix (recombinant zoster vaccine) will not cause a positive varicella zoster virus antibody test result because it contains only the VZV glycoprotein E component rather than the whole virus.

Understanding Shingrix Vaccine Composition

Shingrix is a non-live, recombinant subunit vaccine that contains only the glycoprotein E (gE) component of the varicella zoster virus, rather than the whole virus 1. Unlike the older live-attenuated Zostavax vaccine, Shingrix does not contain live virus particles that could potentially trigger a false positive on a standard VZV antibody test.

How Varicella Zoster Testing Works

Varicella zoster virus antibody tests typically measure:

• VZV IgG antibodies (indicating past infection or immunization)
• VZV IgM antibodies (indicating recent infection)

The standard VZV antibody tests detect antibodies against multiple viral proteins, not just the glycoprotein E that is contained in Shingrix. Therefore:

• Shingrix vaccination induces antibodies specifically against glycoprotein E
• Standard VZV antibody tests detect a broader range of antibodies against the whole virus

Evidence Supporting This Conclusion

The evidence indicates that Shingrix vaccination produces a specific immune response to glycoprotein E rather than generating antibodies that would cause a positive result on standard VZV testing:

1. In studies of VZV-seronegative transplant recipients, even after Shingrix vaccination, only 55% developed a positive seroresponse to the glycoprotein E component, while still remaining negative on standard VZV antibody testing 2.

2. The immune response to Shingrix is measured specifically by anti-glycoprotein E antibodies and VZV-specific T cell responses, not by standard VZV antibody tests 1.

Different Types of Zoster Vaccines

It's important to distinguish between the two types of herpes zoster vaccines:

1. Recombinant Zoster Vaccine (Shingrix):

   • Contains only the glycoprotein E component of VZV
   • Non-live vaccine
   • Will not cause positive standard VZV antibody tests
   • Currently preferred due to higher efficacy 3

2. Live Zoster Vaccine (Zostavax):

   • Contains attenuated live virus
   • Could potentially cause a positive VZV antibody test
   • No longer marketed in the United States 1

Clinical Implications

This distinction has important clinical implications:

• If you need to assess a patient's natural immunity to varicella zoster virus, Shingrix vaccination will not interfere with test interpretation
• Patients who receive Shingrix and later undergo VZV antibody testing will show results that reflect their natural immunity status, not their vaccination status
• For immunocompromised patients who cannot receive live vaccines, Shingrix provides protection without affecting standard VZV antibody test results

Common Pitfalls to Avoid

1. Don't confuse the two types of zoster vaccines: Zostavax (live) might affect VZV antibody testing, while Shingrix (recombinant) will not.

2. Don't rely solely on VZV antibody testing to confirm Shingrix response: The immune response to Shingrix is better measured through anti-glycoprotein E antibodies and cell-mediated immunity 1.

3. Don't assume all "zoster" or "varicella" tests are the same: Different tests detect different components of the immune response to VZV.

In conclusion, patients receiving the Shingrix vaccine can be reassured that it will not cause a false positive result on standard varicella zoster virus antibody testing.