Vaccines

Background: Infectious diseases accounted for approximately 18.4% of global mortality in 2019. According to the World Health Organization (WHO), vaccines are available for about 30 potentially lethal diseases. Vaccination prevents substantial mortality and hospitalization. However, its ability to improve overall public health depends on equitable access across all populations, regardless of race, ethnicity, education, or socioeconomic status. Objectives: This study aims to examine how disparities in social determinants of health (SDOH) affect COVID-19 vaccination uptake across Jefferson County, Kentucky. Using ZIP code–level spatial mapping, this study investigates the intersection of SDOH, racial composition, and geographic characteristics to identify inequities and inform equitable interventions. Methods: Data from the Kentucky Immunization Registry (KYIR) were analyzed to assess two-dose COVID-19 vaccination rates at the ZIP code and regional levels in Jefferson County, Kentucky. Vaccination rates were stratified by race and ethnicity and linked with SDOH, including education, employment, insurance status, and income, obtained from the 2021 American Community Survey. Results: By May 2021, vaccination rates ranged from 25.9% in the West region to 57.0% in the Inner East region; by May 2022, these rates increased to 46.2% and 73.9%, respectively. White residents consistently had the highest two-dose vaccination rates (66.4% by May 2022), while Black and Hispanic residents had lower rates (45.7% and 43.9%, respectively). Vaccination rates were strongly correlated with SDOH, especially educational attainment, average family income, and employment rate, underscoring the role of socioeconomic inequities in vaccination disparities. Conclusions: Geographical and racial disparities emphasize the influence of social and economic inequality on vaccine uptake.

Introduction: The incidence of pneumococcal disease (PD) in people living with HIV (PLWH) is higher than in the general population; therefore, this study aimed to analyze its incidence, clinical characteristics and vaccination coverage in PLWH. Methods: We conducted a retrospective, single-center study between 2015 and 2024 in Hospital Clínic, Barcelona, involving HIV patients who presented with PD during the study period (any patient with a microbiologically confirmed result). A descriptive analysis of cases was carried out and compared with patients who did not present PD during the study period. Results: A total of 177 episodes of PD were identified in 148 individuals, with a cumulative incidence of 1.7% (95% CI: 1.4–2.0). The median age at PD diagnosis was 45.9 (36–53) years; 64% of patients were Spanish-born; 50% of patients were men who have sex with men (MSM); the HIV transmission mode was intravenous drug use in 28% of cases; the median CD4 nadir was 181 (58–324) cells/mm³; the median CD4 prior to PD was 429 (240–663) cells/mm³; and the median peak HIV viral load (VL) was 176,839 (20,900–502,000) copies/mL. Intravenous drug use (OR 3.43; 95% CI 2.19–5.36; p < 0.001), peak HIV VL (OR 1.11; 95% CI 1.02–1.21; p = 0.011), and CD4 nadir (OR 0.92; 95% CI 0.87–0.98; p = 0.005) were independently associated with PD, and fifty-one percent of patients had not received any vaccination prior to their PD episode. Conclusion: PD incidence was high in our study and associated with poor immunological status. Research on new strategies to improve vaccination coverage and immunogenicity in PLWH is needed.

Exosome-based vaccines represent a transformative platform in modern vaccinology, combining nanoscale delivery, biocompatibility, and potent immunogenicity. Among these, the StealthX platform developed by Capricor, Inc. has demonstrated exceptional versatility, enabling antigen presentation at nanogram level doses without the need for adjuvants. Preclinical studies using StealthX have shown strong humoral and cellular immune responses against SARS-CoV-2 variants, including Delta and Omicron, as well as broader applications against influenza and RSV antigens. The platform’s ability to accommodate multiple antigens within a single formulation addresses the challenges of viral variation and facilitates multivalent “mix-and-match” immunization strategies. This review offers an in-depth evaluation of the StealthX vaccine platform, covering the biological mechanisms underlying exosome function, the engineering approaches used to load antigens, and preclinical results demonstrated across three pivotal studies. By synthesizing current evidence, this review underscores the platform’s applicability for emerging infectious diseases and explores the strategic value of multivalent exosome-based vaccines in global immunization efforts as an emerging next-generation vaccine technology.