Safety of inadvertent administration of live zoster vaccine to immunosuppressed individuals in a UK-based observational cohort analysis

Live vaccinations in dermatology for immunosuppressed patients: a narrative review

Given the higher susceptibility to infectious disease in patients receiving immunosuppressive therapies for inflammatory dermatologic conditions, immunization is important in this population. While live vaccines protect against life-threatening diseases, they can be harmful in immunosuppressed patients given the risk of replication of the attenuated pathogen and adverse reactions. The utilization of live vaccines in immunosuppressed patients depends on multiple factors such as the vaccine and therapy regimen. To provide an overview of evidence-based recommendations for the use of live vaccines in patients receiving immunosuppressive therapies for dermatological conditions. A literature search of the PubMed database was performed using keywords live vaccine, live-attenuated vaccine, dermatology, immunosuppressed, and immunocompromised, and specific immunosuppressive therapies: corticosteroids, glucocorticoids, methotrexate, azathioprine, cyclosporine, mycophenolate mofetil, biologics. Relevant articles written in English were included. Using these keywords, 125 articles were reviewed, of which 28 were ultimately selected. Recommendations for live vaccines can be determined on a case-by-case basis. Measles, mumps, rubella, varicella (MMRV) vaccines may be safely administered to patients on low-dose immunosuppressive agents while the yellow fever vaccine is typically contraindicated. It may be safe to administer live MMRV boosters to children on immunosuppressive therapies and the live herpes zoster vaccine to patients on biologics. Given poor adherence to immunization guidelines in immunosuppressed patients, dermatologists have a critical role in educating patients and general practitioners regarding live vaccines. By reviewing a patient's vaccination history and following immunization guidelines prior to initiating immunosuppressive therapies, physicians can mitigate morbidity and mortality from vaccine-preventable diseases.

Disseminated varicella zoster virus infection following live attenuated herpes zoster vaccine: descriptive analysis of reports to Australia's spontaneous vaccine pharmacovigilance system, 2016-2020

OBJECTIVES

To examine the reported incidence and features of disseminated varicella zoster virus (VZV) infection following live attenuated herpes zoster vaccine live (ZVL: Zostavax, Merck) in immunocompromised people in Australia.

DESIGN AND SETTING

ZVL was funded in 2016 in Australia for people aged 70 years, with a catch-up programme for those 71-79 years. From 2016 to 2020, three deaths due to disseminated vaccine-strain VZV infection occurred following inadvertent ZVL administration in individuals with varying levels of immunocompromise. This descriptive study examined 4 years of national surveillance data reported to the Therapeutic Goods Administration's Adverse Event Monitoring System (AEMS). Denominator data for rates were from doses recorded in the Australian Immunisation Register.

PARTICIPANTS

Individuals vaccinated between 1 November 2016 and 31 December 2020 who experienced adverse event(s) following immunisation (AEFI) after ZVL recorded in the AEMS.

PRIMARY AND SECONDARY OUTCOME MEASURES

Rates and outcomes of confirmed (Oka strain positive) or probable disseminated VZV infection, and inadvertent administration of ZVL in immunocompromised individuals.

RESULTS

854 AEFI were reported from 1 089 966 doses of ZVL administered (78.4 per 100 000 doses). Of those, 14 were classified as confirmed (n=6, 0.55 per 100 000) or probable (n=8) disseminated VZV infection. The confirmed cases were all hospitalised, and most (5/6) were immunocompromised; three cases died. Thirty-seven individuals were reported as vaccinated despite a contraindication due to immunocompromise (3.4 per 100 000), with 12/37 (32%) hospitalised.

CONCLUSIONS

Disseminated VZV is potentially life-threatening and occurs mostly in those with severe immunocompromise. Inadvertent administration of ZVL to immunocompromised individuals has occurred despite initial provider guidance and education. Multiple additional strategies to assist providers to identify contraindications have been implemented to prevent adverse outcomes.

Thrombosis and thrombocytopenia after vaccination against and infection with SARS-CoV-2 in the United Kingdom

Population-based studies can provide important evidence on the safety of COVID-19 vaccines. Using data from the United Kingdom, here we compare observed rates of thrombosis and thrombocytopenia following vaccination against SARS-CoV-2 and infection with SARS-CoV-2 with background (expected) rates in the general population. First and second dose cohorts for ChAdOx1 or BNT162b2 between 8 December 2020 and 2 May 2021 in the United Kingdom were identified. A further cohort consisted of people with no prior COVID-19 vaccination who were infected with SARS-Cov-2 identified by a first positive PCR test between 1 September 2020 and 2 May 2021. The fourth general population cohort for background rates included those people in the database as of 1 January 2017. In total, we included 3,768,517 ChAdOx1 and 1,832,841 BNT162b2 vaccinees, 401,691 people infected with SARS-CoV-2, and 9,414,403 people from the general population. An increased risk of venous thromboembolism was seen after first dose of ChAdOx1 (standardized incidence ratio: 1.12 [95% CI: 1.05 to 1.20]), BNT162b2 (1.12 [1.03 to 1.21]), and positive PCR test (7.27 [6.86 to 7.72]). Rates of cerebral venous sinus thrombosis were higher than otherwise expected after first dose of ChAdOx1 (4.14 [2.54 to 6.76]) and a SARS-CoV-2 PCR positive test (3.74 [1.56 to 8.98]). Rates of arterial thromboembolism after vaccination were no higher than expected but were increased after a SARS-CoV-2 PCR positive test (1.39 [1.21 to 1.61]). Rates of venous thromboembolism with thrombocytopenia were higher than expected after a SARS-CoV-2 PCR positive test (5.76 [3.19 to 10.40]).

Safety of live attenuated herpes zoster vaccine in Australian adults 70-79 years of age: an observational study using active surveillance

OBJECTIVES

To assess the safety of live attenuated herpes zoster vaccine live (ZVL) through cumulative analysis of near real-time, participant-based active surveillance from Australia's AusVaxSafety system.

DESIGN AND SETTING

ZVL was funded in Australia for adults aged 70 years from November 2016, with a time-limited catch up programme for those up to 79 years. This cohort study monitored safety in the first two programme years through active surveillance at 246 sentinel surveillance immunisation sites.

PARTICIPANTS

Adults aged 70-79 years vaccinated with ZVL who responded to an opt-out survey sent via automated short message service (SMS) 3 days following vaccination (n=17 458) or contributed supplementary data through a separate, opt-in online survey at 16 and 24 days following vaccination (n=346).

PRIMARY AND SECONDARY OUTCOME MEASURES

Rates of overall and prespecified adverse events following immunisation (AEFI) by sex, concomitant vaccination and underlying medical condition. Signal detection methods (fast initial response cumulative summation and Bayesian updating analyses) were applied to reports of medical attendance.

RESULTS

The median age of participants was 72 years; 53% were female. The response rate following automated SMS was high (73% within 7 days of vaccination). Females were more likely than males to report any adverse event within 7 days of vaccination (RR 2.07, 95% CI 1.86 to 2.31); injection site reaction was the most commonly reported (2.3%, n=377). Concomitant vaccination was not associated with higher adverse event rates (RR 1.05, 95% CI 0.93 to 1.18). Rates of medical attendance were low (0.3%) with no safety signals identified. Supplementary opt-in survey data on later onset adverse events did not identify any difference in AEFI rates between those with and without underlying medical conditions.

CONCLUSIONS

ZVL has a very good safety profile in the first week after vaccination in older adults. Active, participant-based surveillance in this primary care cohort is an effective method to monitor vaccine safety among older adults and will be used as a key component of COVID-19 vaccine safety surveillance in Australia.