A Cross-Sectional Factor Analysis of COVID-19 and Influenza Vaccination Decisions in a Racially Diverse Western Pennsylvania Community

Introduction: Influenza and COVID-19 vaccination rates remain suboptimal, demanding new community-centric approaches that improve targeted counseling and increase vaccine uptake. Notably, racially diverse communities show high vaccine hesitancy, yet most existing vaccine studies focus on white, college-educated cohorts. Objective: Here, we identify factors influencing vaccination decisions of patients at Turtle Creek Primary Care clinic in Turtle Creek, PA, a racially-diverse borough. Design: A retrospective mixed-methods study of the predominantly non-white patient population at Turtle Creek Primary Care clinic, a clinic caring for >70% minority patients. Results: Fourteen factors emerged that patients reported were crucial to vaccine decision-making. Of these factors, top reasons for COVID-19 vaccine hesitancy were trust in vaccines, vaccine side effects, perceived vaccine knowledge, and faith/religion. Top reasons for influenza vaccine hesitancy were perceived need, vaccine side effects, trust in vaccines, and habitual behaviors. We also uncovered correlations between vaccine decision factors and sociodemographic factors. Participants > 65-years-old were more likely to cite personal safety in choosing to get the COVID-19 vaccine, while non-white participants were more likely to cite others’ safety. Participants > 65-years-old were also more likely to cite personal safety in influenza vaccine decision-making, and non-female participants were more likely to cite perceived need for influenza vaccines. Conclusions: These data uncover targetable factors contributing to vaccine hesitancy and aid in developing community-centered, personalized vaccine education approaches in Turtle Creek and analogous minority communities

Distinct roles for type I and type III interferons in virulent human metapneumovirus pathogenesis.

Human metapneumovirus (HMPV) is an important cause of acute lower respiratory infection in children and adults worldwide. There are four genetic subgroups of HMPV and both neutralizing antibodies and T cells contribute to protection. However, little is known about mechanisms of pathogenesis and most published work is based on a few extensively passaged, laboratory-adapted strains of HMPV. In this study, we isolated and characterized a panel of low passage HMPV clinical isolates representing all four genetic subgroups. The clinical isolates exhibited lower levels of in vitro replication compared to a lab-adapted strain. We compared disease phenotypes using a well-established mouse model. Several virulent isolates caused severe weight loss, lung pathology, airway dysfunction, and fatal disease in mice, which was confirmed in three inbred mouse strains. Disease severity did not correlate with lung viral titer, as virulent strains exhibited restricted replication in the lower airway. Virulent HMPV isolates were associated with markedly increased proinflammatory cytokine production and neutrophil influx; however, depletion of neutrophils or genetic ablation of inflammasome components did not reverse disease. Virulent clinical isolates induced markedly increased type I and type III interferon (IFN) secretion in vitro and in vivo. STAT1/2-deficient mice lacking both type I and type III IFN signaling showed reduced disease severity and increased lung viral replication. Inhibition of type I IFN signaling using a blocking antibody or genetic ablation of the type I IFN receptor reduced pathology with minimal effect on viral replication. Conversely, blockade of type III IFN signaling with a neutralizing antibody or genetic ablation of the IFN-lambda receptor had no effect on pathogenesis but restored viral replication. Collectively, these results demonstrate distinct roles for type I and type III IFN in HMPV pathogenesis and immunity

Terminally exhausted CD8+ T cells contribute to age-dependent severity of respiratory virus infection

Abstract Background Lower respiratory infections are a leading cause of severe morbidity and mortality among older adults. Despite ubiquitous exposure to common respiratory pathogens throughout life and near universal seropositivity, antibodies fail to effectively protect the elderly. Therefore, we hypothesized that severe respiratory illness in the elderly is due to deficient CD8+ T cell responses. Results Here, we establish an aged mouse model of human metapneumovirus infection (HMPV) wherein aged C57BL/6 mice exhibit worsened weight loss, clinical disease, lung pathology and delayed viral clearance compared to young adult mice. Aged mice generate fewer lung-infiltrating HMPV epitope-specific CD8+ T cells. Those that do expand demonstrate higher expression of PD-1 and other inhibitory receptors and are functionally impaired. Transplant of aged T cells into young mice and vice versa, as well as adoptive transfer of young versus aged CD8+ T cells into Rag1 −/− recipients, recapitulates the HMPV aged phenotype, suggesting a cell-intrinsic age-associated defect. HMPV-specific aged CD8+ T cells exhibit a terminally exhausted TCF1/7− TOX+ EOMES+ phenotype. We confirmed similar terminal exhaustion of aged CD8+ T cells during influenza viral infection. Conclusions This study identifies terminal CD8+ T cell exhaustion as a mechanism of severe disease from respiratory viral infections in the elderly