Ageing of Immune System and Response to a Live-Attenuated Herpes Zoster Vaccine in Lung Transplant Candidates

Safety and efficacy of recombinant and live herpes zoster vaccines for prevention in at-risk adults with chronic diseases and immunocompromising conditions

Compared with the general population, older adults with immune senescence and individuals who are immunocompromised (IC) due to disease or immunosuppressive therapy are at increased risk for herpes zoster (HZ) and its associated complications, which can be debilitating and life-threatening. Vaccination can be an effective strategy against HZ and studies have shown that HZ vaccination in IC individuals can elicit immune responses and provide protection from infection. Recently, the first approvals have been granted in the United States and the European Union for the recombinant HZ vaccine (RZV) in adults ≥ 18 years of age at risk of HZ due to immunodeficiency or immunosuppression. Existing systematic reviews have highlighted the risks for HZ in limited immunocompromising conditions and have only examined clinical data for RZV. This review details the risks and burden of HZ in a broad range of clinically relevant IC populations and summarizes key efficacy and safety data for RZV and live HZ vaccine in these individuals. Research has shown IC individuals can benefit from HZ vaccination; however, these insights have yet to be fully incorporated into vaccination guidelines and clinical care. Clinicians should consider HZ vaccination in eligible at-risk populations to protect against HZ and its associated complications and thereby, reduce the burden that HZ poses on the healthcare system. Electronic health records and linked personal health records could be used to identify and contact patients eligible for HZ vaccination and provide clinical decision support-generated alerts for missing or delayed vaccinations. This review will help clinicians identify eligible IC individuals who may benefit from HZ vaccination. A video abstract linked to this article is available on Figshare https://doi.org/10.6084/m9.figshare.21517605.

Depression, aging, and immunity: implications for COVID-19 vaccine immunogenicity

The aging process can have detrimental effects on the immune system rendering the elderly more susceptible to infectious disease and less responsive to vaccination. Major depressive disorder (MDD) has been hypothesized to show characteristics of accelerated biological aging. This raises the possibility that depressed individuals will show some overlap with elderly populations with respect to their immune response to infection and vaccination. Here we provide an umbrella review of this literature in the context of the SARS CoV-2 pandemic. On balance, the available data do indeed suggest that depression is a risk factor for both adverse outcomes following COVID-19 infection and for reduced COVID-19 vaccine immunogenicity. We conclude that MDD (and other major psychiatric disorders) should be recognized as vulnerable populations that receive priority for vaccination along with other at-risk groups.

Effect of Cytomegalovirus on the Immune System: Implications for Aging and Mental Health

Human cytomegalovirus (HCMV) is a major modulator of the immune system leading to long-term changes in T-lymphocytes, macrophages, and natural killer (NK) cells among others. Perhaps because of this immunomodulatory capacity, HCMV infection has been linked with a host of deleterious effects including accelerated immune aging (premature mortality, increased expression of immunosenescence-linked markers, telomere shortening, speeding-up of epigenetic "clocks"), decreased vaccine immunogenicity, and greater vulnerability to infectious diseases (e.g., tuberculosis) or infectious disease-associated pathology (e.g., HIV). Perhaps not surprisingly given the long co-evolution between HCMV and humans, the virus has also been associated with beneficial effects, such as increased vaccine responsiveness, heterologous protection against infections, and protection against relapse in the context of leukemia. Here, we provide an overview of this literature. Ultimately, we focus on one other deleterious effect of HCMV, namely the emerging literature suggesting that HCMV plays a pathophysiological role in psychiatric illness, particularly depression and schizophrenia. We discuss this literature through the lens of psychological stress and inflammation, two well-established risk factors for psychiatric illness that are also known to predispose to reactivation of HCMV.