The Association of Previous Vaccination with Live-Attenuated Varicella Zoster Vaccine and COVID-19 Positivity: An Israeli Population-Based Study.

Eugene Merzon,Shlomo Vinker,Avivit Golan-Cohen,Milana Frenkel-Morgenstern,Alessandro Gorohovski,Ariel Israel,Ilan Green,Michal Stein,Eli Somekh

doi:10.3390/vaccines10010074

Abstract

The Bacillus Calmette–Guérin (BCG) vaccine affords indirect protection against COVID-19, which is presumably due to priming of the innate immune system. It was hypothesized that the live attenuated Varicella Zoster (LAVZ) vaccine, recommended for the elderly population, would also protect against COVID-19 infection. A retrospective population-based cross-sectional study was conducted using the Leumit Health Services (LHS) database. LAVZ-vaccinated patients were matched with controls based on a propensity score model using 1:9 nearest-neighbor matching. Matching was based on age, gender, and the presence of some chronic disorders, which were selected according to their association with COVID-19 infection. Multivariate logistic regression analyses, adjusted for sex, age, smoking status, comorbidities, and chronic medications associated with COVID-19 risk, were used to estimate the association between LAVZ vaccination and COVID-19 RT-PCR results. Subjects (625) vaccinated with LAVZ and RT-PCR-tested for COVID-19 were identified. After 1:9 matching of subjects who received the LAVZ vaccine, 6250 subjects were included in the study. Multivariate logistic regression analysis demonstrated a significant and independent negative association between having received the LAVZ vaccine and the likelihood of COVID-19 infection (adjusted OR = 0.47 (95% CI 0.33–0.69, p < 0.001)). This association was further strengthened after separate analysis based on the time of LAVZ vaccination before COVID-19 RT-PCR testing. Individuals aged ≥50 years vaccinated with LAVZ had a decreased likelihood of being tested positive for COVID-19.

Highlights

Multivariate logistic regression analyses, adjusted for sex, age, smoking status, comorbidities, and chronic medications associated with COVID-19 risk [29,30,31,32] were used to estimate the adjusted odds ratio (OR) and 95% CI for the independent association between live attenuated Varicella Zoster (LAVZ) vaccination and COVID-19 RT-PCR test results
A total of 625 subjects were identified who were vaccinated for Varicella Zoster (VZ)
The Ggplot2 R package (Hadley Wickham, LAVZ vaccine, a total of 6250 subjects were included in the study (Figure 1)

Summary

Introduction

Clinical observations have revealed that the beneficial effects of vaccines extend far beyond the direct effect on the disease for which they are intended. Studies published in the last decade showed that children vaccinated against measles with the measles–mumps–rubella (MMR) vaccine showed a 30% reduction in mortality from any cause, only 4% of the decline could be explained by the immunization against measles. The beneficial effect of the MMR vaccine appears to be derived in part from the direct heterologous benefits of measles vaccines that enhance innate and adaptive immune responses, as well as the prevention of measles and measles-associated short- and long-term immunomodulation effects [1,2]. Bacillus Calmette–Guérin (BCG) vaccine provided a reduction in mortality far beyond reducing tuberculosis mortality in studies from Sweden, West Africa, and Guinea-Bissau [3,4,5]. The vaccine appeared to confer broad enhanced immunity to respiratory infections, even in elderly populations [3,4,6,7]

Methods

Results

Conclusion