Determination of varicella-zoster virus (VZV) immune status with the VIDAS VZV immunoglobulin G automated immunoassay and the VZVScan latex agglutination assay

Live Attenuated Zoster Vaccine Boosts Varicella Zoster Virus (VZV)-Specific Humoral Responses Systemically and at the Cervicovaginal Mucosa of Kenyan VZV-Seropositive Women

Background

Attenuated varicella zoster virus (VZV) is a promising vector for recombinant vaccines. Because human immunodeficiencyvirus (HIV) vaccines are believed to require mucosal immunogenicity, we characterized mucosal VZV-specific humoral immunity following VZV_Oka vaccination.

Methods

Adult Kenyan VZV-seropositive women (n = 44) received a single dose of the live zoster VZV_Oka vaccine. The anamnestic responses to the virus were followed longitudinally in both plasma and mucosal secretions using an in-house glycoprotein enzyme-linked immunosorbent assay and safety and reactogenicity monitored. VZV seroprevalence and baseline responses to the virus were also characterized in our cohorts (n = 288).

Results

Besides boosting anti-VZV antibody responses systemically, vaccination also boosted anti-VZV immunity in the cervicovaginal mucosa with a 2.9-fold rise in immunoglobulin G (P < .0001) and 1.6-fold rise in immunoglobulin A (IgA) (P = .004) from the time before immunization and 4 weeks postvaccination. Baseline analysis demonstrated high avidity antibodies at the gastrointestinal and genital mucosa of VZV-seropositive women. Measurement of VZV-specific IgA in saliva is a sensitive tool for detecting prior VZV infection.

Conclusions

VZV_Oka vaccine was safe and immunogenic in VZV-seropositive adult Kenyan women. We provided compelling evidence of VZV ability to induce genital mucosa immunity.

Clinical Trials Registration

NCT02514018.

Prior varicella zoster virus exposure in IBD patients treated by anti-TNFs and other immunomodulators: implications for serological testing and vaccination guidelines

BACKGROUND

Varicella zoster virus (VZV) is a severe and preventable infection in immunosuppressed IBD patients. ECCO guidelines recommend VZV immunisation in patients with negative VZV exposure history. The value of patient-reported VZV exposure history for prediction of seropositivity in IBD patients remains unknown. Moreover, data on VZV immunity in adult IBD patients or accuracy of VZV serological testing under immunomodulator treatment is sparse.

AIMS

The primary aim was to determine the prevalence of seropositivity for VZV-IgG in immunomodulator-treated IBD patients. A secondary aim was to establish the value of patient-reported history of past VZV infection for prediction of immunity, to validate the current vaccination strategy.

METHODS

History of VZV-related illness was accessed by epidemiological questionnaire, and serological testing for VZV-IgG was performed. Serum anti-TNF medications levels were measured when applicable.

RESULTS

One hundred twenty one IBD (86% Crohn's disease, mean age 37 ± 12.8) patients were included in the study. Immunomodulator therapy was received by 87% (anti-TNFs- 71%) of the patients. Previous exposure to VZV was reported by 104 patients, and 97/104 (93%) were VZV-IgG seropositive. Seventeen patients, all seropositive, reported negative exposure history. The calculated positive and negative predictive values for the reported history of VZV exposure were 93% and 0% respectively.

CONCLUSIONS

Negative history of VZV exposure is a poor predictor of seronegativity. History-positive patients may still be seronegative and exposed to VZV infection. We suggest serological testing of all IBD patients with subsequent immunisation of the seronegative patients before initiation of immunosuppressive therapy.