Unvaccinated Individuals Research Articles

Medical Students' Efforts to Address COVID-19 Vaccine Hesitancy Through Motivational Interviewing.

Background The coronavirus disease 2019 (COVID-19) pandemic reaffirmed health disparities in the United States (US) and highlighted the need for public health strategies to combat vaccine hesitancy, especially amongst vulnerable populations. The Green Family Foundation Neighborhood Health Education Learning Program (NeighborhoodHELP) at Florida International University (FIU) serves a predominantly uninsured population, making it a critical area of opportunity for addressing vaccine hesitancy. Motivational interviewing (MI), a technique that supports individuals in making autonomous health decisions, has shown promise in encouraging vaccine acceptance.Medical students at FIU's Herbert Wertheim College of Medicine (HWCOM) are involved in the longitudinal care of the individuals in NeighborhoodHELP and receive training in MI within their clinical skills curriculum, making them optimally positioned to conduct outreach to encourage COVID-19 vaccination. Project goals There were two primary goals of this project: first, to systematically track and improve COVID-19 vaccination rates among individuals in NeighborhoodHELP, andsecond, to equip future physicians with hands-on experience in MI. Methods The COVID-19 Vaccination Promotion Initiative recruited medical students previously trained in MI to conduct outreach to unvaccinated individuals within NeighborhoodHELP. Students engaged in discussions about the COVID-19 vaccine with NeighborhoodHELP members, assisted in scheduling vaccination appointments, and updated medical records. The student team regularly met with faculty advisors to discuss changes in vaccine and public health data and to discuss challenges and successes with outreach efforts. To incentivize participation and enhance vaccine uptake, $25 gift cards were offered to individuals who agreed to receive the vaccine following the outreach conversations. Results From June 2021 to January 2023, the team made an estimated 720-1516 phone calls to NeighborhoodHELP individuals. The team encountered a challenge of low answering rates, with 35% of individuals being unreachable despite multiple attempts. Among those reached, 20% expressed no interest in receiving the vaccine, while 50% were interested in receiving the vaccine or had already been vaccinated. Vaccination rates among NeighborhoodHELP adults rose from 15.2% to 44.3% during this time. Student experiences with MI were generally positive, with many noting success in engaging hesitant individuals. However, the team also encountered challenges, such as growing vaccine apathy within the community and difficulties in reaching patients via cold calls, which limited the overall impact of their outreach efforts. Conclusions By using MI techniques,medical students engaged with community members in meaningful conversations about the importance and safety of COVID-19 vaccination.However,the initiative fell short of the 50% vaccination target, facing challenges such asreliance on unsolicited phone calls and the complexities of incentivizing vaccinations through this outreach method. Future initiatives could benefit from exploring alternative outreach methods, such as in-person engagement at community events or through partnerships with local organizations, to overcome the limitations of phone-based outreach. Additionally, investigating the relative efficacy of in-person versus telephone-based communication in promoting vaccination could provide valuable insights.

Prevalence of Oral Human Papillomavirus Infection Among Urban Gay, Bisexual, and Other Men Who Have Sex With Men in Canada, 2017-2019.

Oral human papillomavirus (HPV) infections are a leading cause of oropharyngeal cancers. In 2015 and 2016, HPV vaccines became publicly funded for gay, bisexual, and other men who have sex with men (GBM) under 27 years of age in most Canadian provinces. Between 2017 and 2019, sexually-active GBM in Montreal, Toronto, and Vancouver were recruited through respondent-driven sampling. Participants aged 16 to 30 years were invited to self-collect oral rinse specimens for HPV testing. We estimated HPV prevalence in the oral tract overall and compared these by vaccination status. Among the 838 GBM with a valid oral specimen, 36.9% reported receiving ≥1 dose of HPV vaccine. Overall, oral HPV prevalence was 2.6% (95% confidence interval, CI: 1.5, 3.7%) for at least one HPV type and 1.2% (95% CI: 0.5, 1.9%) for any high-risk type. We detected quadrivalent (HPV 6/11/16/18) vaccine-preventable types in 0.3% (95% CI: 0.0, 1.0%) of vaccinated individuals and 1.1% (95% CI: 0.1, 2.0%) in unvaccinated individuals. Oral HPV prevalence was low in a population of young urban GBM in Canada of whom 37% were vaccinated. Findings serve as a benchmark for monitoring of vaccination impacts on oral HPV infection within this priority population.

Severity outcomes of SARS-CoV-2 infection in the Omicron and pre-Omicron periods, in unvaccinated first-time test positive adults less than 65 years old without comorbidity, in Sweden

BackgroundThe COVID-19 pandemic has had several phases with varying characteristics. We aimed to compare severity outcomes in different phases in a population with limited bias from risk factors. MethodsIn a nationwide observational study of all unvaccinated first-time COVID-19 test positive individuals in Sweden aged 18–64 years without comorbidity, from week 45 of 2020 to week 5 of 2022, variant periods with certain variants constituting ≥ 92 % of all whole genome-sequenced cases nationwide, were compared regarding hospitalisation (with main discharge code of COVID-19), severe illness (use of high-flow nasal oxygen or admission to intensive care unit), and death due to COVID-19. Logistic regression was used to estimate odds ratios (ORs) for comparison of these outcomes between variant periods, using adjustments for variant period, age, sex, country of birth, place of residence, income, and education. FindingsThe study included 789,133 individuals, including 15,145 hospitalised individuals. Among all individuals, the adjusted ORs for hospitalisation were 1.7 for the Alpha period vs the Pre-variant period (week 45–52 2020), 1.8 for the Delta period vs the Alpha period, and 0.1 for the Omicron period vs the Delta period (all comparisons significant). Among hospitalised individuals, the adjusted ORs for severe illness were 1.4 for the Alpha period vs the Pre-variant period, 1.7 for the Delta period vs the Alpha period, and 0.5 for the Omicron period vs the Delta period (all comparisons significant), and the adjusted ORs for death were 1.1 for the Alpha period vs the Pre-variant period (non-significant), 1.8 for the Delta period vs the Alpha period (significant), and 0.1 for the Omicron period vs the Delta period (non-significant). InterpretationIn this population with limited bias from risk factors, vaccination, and previous infection, disease severity increased from the pre-variant to the Delta period and then decreased with the Omicron period, among all individuals and among hospitalised individuals. These severity outcome differences should be considered when the pandemic is evaluated.

Predominance of CD137+ And TNF-α Expressing CD8+ Central Memory T Cells in Mild COVID-19 Recovered Patients Upon SARS-CoV-2 Re-Exposure

ABSTRACT Introduction Memory CD8+ T cells are essential for long-term immune protection in viral infections, including COVID-19. Methods This study examined the responses of CD8+ TEM, TEMRA, and TCM subsets from unvaccinated individuals who had recovered from mild and severe COVID-19 by flow cytometry. Results and Discussion The peptides triggered a higher frequency of CD8+ TCM cells in the recovered mild group. CD8+ TCM and TEM cells showed heterogeneity in CD137 expression between evaluated groups. In addition, a predominance of CD137 expression in naïve CD8+ T cells, TCM, and TEM was observed in the mild recovered group when stimulated with peptides. Furthermore, CD8+ TCM and TEM cell subsets from mild recovered volunteers had higher TNF-α expression. In contrast, the expression partner of IFN-γ, IL-10, and IL-17 indicated an antiviral signature by CD8+ TEMRA cells. These findings underscore the distinct functional capabilities of each memory T cell subset in individuals who have recovered from COVID-19 upon re-exposure to SARS-CoV-2 antigens.

Neutralizing antibody responses assessment after vaccination in people living with HIV using a surrogate neutralization assay

ObjectiveHIV has been reported to interfere with protective vaccination against multiple pathogens, usually through the decreased effectiveness of the antibody responses. We aimed to assess neutralizing antibody responses induced by COVID-19 vaccination in PLWH in Brazzaville, Republique of the Congo.MethodThe study was conducted at the Ambulatory Treatment Center of the National HIV Program, in charge of over 6000 PLWH, and the health center of FCRM in Brazzaville, Republic of the Congo. Participants were divided into two groups: PLWH with well-controlled HIV infection (CD4 counts no older than one week ≥ 800 / mm3, undetectable viral load of a period no older than one week and regularly taking Highly Active Antiretroviral Therapy for at least 6 months) and PLWOH. These groups were subdivided by vaccination status: fully vaccinated with adenovirus-based vaccines (Janssen/Ad26.COV2.S and Sputnik/Gam-COVID-Vac) or inactivated virus vaccine (Sinopharm/BBIP-CorV) and a control group of unvaccinated healthy individuals. All participants were RT-PCR negative at inclusion and/or with no documented history of SARS-CoV-2 infection. ELISA method was used for detecting IgG and neutralizing Antibodies against SARS-CoV-2 antigens using a commercial neutralizing assay.ResultsWe collected oropharyngeal and blood samples from 1016 participants including 684 PLWH and 332 PLWOH. Both PLWH and PLWOH elicited high levels of antibody responses after complete vaccination with inactivated virus vaccine (Sinopharm/BBIP-CorV) and adenovirus-based vaccines (Janssen/Ad26.COV2.S and Sputnik/Gam-COVID-Vac). Overall, no difference was observed in neutralization capacity between PLWOH and PLWH with well-controlled HIV infection.ConclusionThe results from this study underline the importance of implementing integrated health systems that provide PLWH the opportunity to benefit HIV prevention and care, at the same time while monitoring their vaccine-induced antibody kinetics for appropriate booster schedules.

New Russian Trivalent Hepatitis B Vaccine (Bubo®­-Unigep): Reactogenicity, Safety and Immunological Efficacy

Relevance. In Russia, phase III of clinical trials of the domestic trivalent vaccine Bubo®-Unigep, containing protective antigens that provide protection against “wild” forms of the hepatitis B virus subtypes ay and ad, as well as the determinant of serotype ay with the G145R mutation, has been completed. Аim. Evaluation of the effect of the new recombinant polyvaccine against hepatitis B «Bubo-Unigep» on vital functions and laboratory parameters in previously unvaccinated individuals in an adult healthy population. Materials and methods. A randomized multicenter clinical study was conducted to assess the reactogenicity, safety and immunogenicity of Bubo®-Unigep (CJSC NPC «COMBIOTECH») in previously unvaccinated healthy adults (n = 166). The study performed according to the protocol developed by the contract research organization «R&D Pharma» at eight clinical centers located in Russian Federation. Results and discussion. Analysis of the studied parameters throughout the study (frequency and severity of adverse events, physical examination data of volunteers with assessment of vital signs, laboratory test results, etc.) made it possible to establish a high safety profile of Bubo®-Unigep vaccine, which turned out to be virtually areactogenic without causing development of targeted local and systemic post-vaccination adverse events. Conclusion. The wide range of specificity of the immune response, along with the high safety and reactogenicity of the Bubo®-Unigep vaccine, the production of which can be carried out through a full technological cycle without the use of imported substances, will increase the effectiveness of hepatitis B prevention.

Vaccination homophily in ego contact networks during the COVID-19 pandemic

Vaccine hesitancy is an inevitable risk for societies as it contributes to outbreaks of diseases. Prior research suggests that vaccination decisions of individuals tend to spread within social networks, resulting in a tendency to vaccination homophily. The clustering of individuals resistant to vaccination can substantially make the threshold necessary to achieve herd immunity harder to reach. In this study, we examined the extent of vaccination homophily among social contacts and its association with vaccine uptake during the COVID-19 pandemic in Hungary using a contact diary approach in two cross-sectional surveys. The results indicate strong clustering among both vaccinated and unvaccinated groups. The most powerful predictor of vaccine uptake was the perceived vaccination rate within the egos’ social contact network. Vaccination homophily and the role of the interpersonal contact network in vaccine uptake were particularly pronounced in the networks of close relationships, including family, kinship, and strong social ties of the ego. Our findings have important implications for understanding COVID-19 spread dynamics by showing that the strong clustering of unvaccinated individuals posed a great risk in preventing the spread of the disease.

Three-year Profile of COVID-19 Cases in Eastern Visayas, the Philippines (2020–2023)

This paper presents a three-year profile of laboratory-confirmed COVID-19 cases in Eastern Visayas, the Philippines, from 23 Mar 2020–31 Mar 2023 – with descriptive data on temporal trends, geographical variations, demographic factors, clinical characteristics, transmission patterns, and outcomes for vaccinated and unvaccinated cases. We analyzed data from the Regional Epidemiology and Surveillance Unit, Department of Health–Eastern Visayas Center for Health and Development to identify associations between COVID-19 severity and mortality and demographic and clinical factors. Moreover, we examined significant differences across gender cohorts and between vaccinated and unvaccinated individuals. During the three-year period, Eastern Visayas recorded 64,740 confirmed cases, with 98.93% recovery and 1.07% mortality. Most cases (61.72%) occurred in 2021 – with Tacloban, Ormoc, and Leyte having the highest attack rates per 100,000 population. Infections were asymptomatic (70.40%) or mild (21.83%), and 82.7% of deaths were linked to severe infections. Females accounted for 52.6% of the patients, with a lower mortality rate (44.5%) than males (55.5%). The 20–29 age group had the highest count (22.57%), whereas the 70–79 age group recorded the highest number of deaths (25.94%). The vast majority (93.6%) had no comorbidities. Comorbidities reported among deaths included kidney disease (11.3%), heart disease (7.6%), and hypertension (3.9%). Notably, no significant differences in recoveries and deaths were found between vaccinated and unvaccinated groups (p-value = 0.304). Logistic regression analysis showed that gender, age group, place of residence, comorbidity, and vaccination status were significantly associated with disease severity and mortality. Eastern Visayas demonstrated a relatively low COVID-19 caseload (1.59%) within the cumulative Philippine count. This is the most extensive COVID-19 case profile in the Philippines to date, hence providing essential data for pandemic preparedness, enhanced response strategies, and regional health crisis resilience.

Blood serum biomarkers in the dynamics of treatment for cerebrovascular pathology in post-COVID-19 patients

Neurological manifestations after COVID-19 infections can be attributed to chronic immune and inflammatory reactions induced by SARS-CoV-2, as well as endothelial dysfunction and other vascular issues. This study included 24 patients with cerebrovascular disease (CVD) who had contracted COVID-19 1 – 1.5 years before the examination (experimental group) and 20 patients with CVD who had not previously been infected with the coronavirus (comparison group). Both groups were representative in terms of age and gender. Blood serum biomarkers, including interleukin (IL)-6, endothelin-1 (ET-1), and vascular endothelial growth factor A (VEGF-A), were tested before and after a 14-day standard complex therapy in the hospital at our institute using appropriate enzyme-linked immunosorbent assay reagent kits. Increases in the levels of IL-6 (by 20%), ET-1 (by 200%), and VEGF-A (by 100%) were observed in patients with CVD who had contracted COVID-19 1 – 1.5 years earlier compared to the comparison group. The effectiveness of a 2-week therapeutic intervention in patients with a history of COVID-19 was found only for VEGF-A: its serum level decreased twofold, leading to the normalization of this indicator. The concentrations of IL-6 and ET-1 were not affected by the treatment. In addition, the serum levels of ET-1 and VEGF-A in unvaccinated individuals exceeded those in vaccinated patients.

Diagnostic features of autoimmune hepatitis in SARS‑CoV‑2‑vaccinated vs. unvaccinated individuals.

The global coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected millions of lives, leading to significant morbidity and mortality. With >772 million cases and nearly seven million deaths reported worldwide to date, the development of vaccines has been a critical step in mitigating the impact of COVID-19. However, concerns have arisen regarding the potential for SARS-CoV-2 mRNA vaccination to trigger autoimmune diseases, including autoimmune hepatitis (AIH). The present single-center, retrospective study aimed to compare the clinical and pathological features of AIH in patients with or without a history of SARS-CoV-2 mRNA vaccination. A total of 72 patients with AIH were examined. Among them, 10 had received the SARS-CoV-2 mRNA vaccination prior to AIH onset. These patients exhibited more pronounced CD4+ T cell infiltration into the liver tissue compared with those who were unvaccinated. No significant differences in the levels of other liver enzymes, autoimmune antibodies, or CD8+ T cell infiltration were observed between the groups. Moreover, the AIH patients with a history of SARS-CoV-2 mRNA vaccination had more extensive CD4+ T cell infiltration in their liver tissues than the unvaccinated patients. These findings suggested that the immune response to SARS-CoV-2 mRNA vaccination may influence the pathogenesis of AIH, highlighting the need for further research into the relationship between SARS-CoV-2 mRNA vaccination and autoimmune liver diseases. Such studies will also help clarify the distinction between vaccine-induced liver injury and traditional AIH.

Zoster Vaccine Lowers Stroke and Myocardial Infarction Risk in Chronic Disease

Herpes zoster increases stroke and myocardial infarction (MI) risk. The objective of this study is to evaluate the impact of live attenuated zoster vaccination on stroke and MI risk in patients at-risk for zoster including persons with hypertension, diabetes mellites, obesity, hypercholesterolemia, chronic kidney disease, chronic obstructive pulmonary disease, emphysema, asthma, and chronic liver disease. Retrospective cohort study utilizing continuous de-identified claims data from the IBM MarketScan® Commercial Claims and Encounters Database (collected from 2005-2018) containing data for 200 million commercially insured Americans. Participants included 27,093 adults vaccinated against zoster with at least 5 years continuous enrollment, age and sex-matched 1:5 with unvaccinated controls. Odds ratios, risk difference, and number needed to treat (NNT) evaluated the effect of vaccination on stroke and MI while controlling for relevant comorbidities. Over five years, proportions of MI (1.29% vs 1.82%; p<0.05) and stroke (1.61% vs. 2.20%; p<0.05) were lower in vaccinated versus unvaccinated individuals respectively, controlling for age and sex, with greatest benefit for people with diabetes (stroke OR [95% Confidence Limits] 0.64 [0.58, 0.71], MI 0.63 [0.57, 0.71]). Although hypertension and chronic obstructive pulmonary disease (COPD) had highest odds of stroke and MI, vaccination still provided significant risk-reduction (Hypertension: stroke 0.75 [0.68, 0.83], MI 0.73 [0.65, 0.81]; COPD: stroke 0.75 [0.68, 0.83], MI 0.74 [0.66, 0.83]). Live attenuated zoster vaccination is associated with lower risk stroke and MI in adults with at-risk comorbidities, controlling for age and sex. Vaccination may provide cardiovascular benefits beyond zoster prevention.

Association of Coronavirus Disease 2019 Vaccination with Facial-Related Neurological Disorders: A Nationwide Retrospective Cohort Study.

Neurological complications after the coronavirus disease 2019 (COVID-19) vaccine administration have been reported. However, the incidence rates of these complications have not been compared in vaccinated and unvaccinated individuals. This study used a nationwide cohort from South Korea to investigate the incidence and prognostic factors of facial-related neurological disorders, such as facial palsy, trigeminal neuralgia, and hemifacial spasms, after COVID-19 vaccination. A population-based cohort design was used to examine data from a randomly selected 50% of the adult population in Seoul, South Korea. Information on demographics, vaccination status, vaccination type, and medical history was collected. The incidence rates and adjusted hazard ratios (aHRs) for facial-related neurological disorders were calculated. This study included 2,482,481 adults, 85.94% of whom were vaccinated. Vaccinated individuals showed a higher incidence of facial palsy, hemifacial spasm, and trigeminal neuralgia than unvaccinated individuals, with significant aHRs of 1.821, 3.203, and 6.621, respectively. Dyslipidemia, female sex, and young age were identified as risk factors for hemifacial spasms and trigeminal neuralgia. This study demonstrates an increased incidence of facial-related neurological disorders after COVID-19 vaccination, particularly among individuals with dyslipidemia and younger women. These findings underscore the need for further investigations into the mechanisms and management of vaccine-related neurological issues.

The vaccination divide: Exploring moral reasoning associated with intergroup antipathy between vaccinated and unvaccinated people.

There is growing evidence of intergroup hostility between vaccinated and unvaccinated individuals, a process of polarization that threatens to derail population health efforts. This study explores the moral underpinnings of intergroup antipathy between vaccinated and unvaccinated individuals. A cross-sectional design was employed to investigate the associations between the view of vaccination as a social contract or individual choice, perceived vulnerability to disease, perceptions of outgroup morality, feelings of warmth, and experiences of schadenfreude. Data were extracted from an online, quantitative survey of 233 vaccinated and 237 unvaccinated participants collected between June and July 2022. Results revealed that vaccinated people had stronger negative attitudes towards unvaccinated people than vice versa. In line with hypotheses, the extent to which vaccinated people saw vaccination as a social contract was significantly associated with perceiving unvaccinated people as immoral. For unvaccinated people, seeing vaccination as an individual choice (the opposite of a social contract) was significantly associated with perceiving vaccinated people as immoral. Among both groups, viewing the other as immoral was associated with feeling significantly less warmth towards the opposing vaccination group, and more schadenfreude in the face of an outgroup member's suffering. Participants' perceived vulnerability to disease played a relatively small role in explaining polarization between vaccinated and unvaccinated people. This research builds on previous studies by identifying moral mechanisms associated with intergroup antipathy in the vaccine debate.

Investigating the causal effects of COVID-19 vaccination on the adoption of protective behaviors in Japan: Insights from a fuzzy regression discontinuity design.

During the COVID-19 pandemic, concerns emerged that vaccinated individuals might engage less in infection-preventive behaviors, potentially contributing to virus transmission. This study evaluates the causal effects of COVID-19 vaccination on such behaviors within Japan, highlighting the significance of understanding behavioral dynamics in public health strategies. Utilizing Japan's age-based vaccination priority for those born before April 1, 1957, this research employs a regression discontinuity design (RDD) to assess the vaccination's impact. Data from the fourth round of a longitudinal online survey, conducted from July 20 to 27, 2021, served as the basis for analyzing 14 infection-protective behaviors, including mask usage, handwashing, and avoiding crowds. A total of 12067 participants completed the survey. The analyzed sample size varied by outcome variable, ranging from 1499 to 5233. The analysis revealed no significant differences in the 14 behaviors examined among fully vaccinated, partially vaccinated, and unvaccinated individuals. This consistency across groups suggests that vaccination status did not significantly alter engagement in protective behaviors during the observation period. Empirical findings highlight the complexity of behavioral responses following vaccination, indicating that such responses may be influenced by various factors, rather than by vaccination status alone. Additionally, this result underscores the importance of crafting public health policies that account for the intricate interplay between vaccination and behavior. This study contributes to the broader discourse on managing responses to the pandemic and tailoring interventions to sustain or enhance protective health behaviors amid vaccination rollouts.

Risk of Post-COVID-19 Uveitis and Risk Modification by Vaccination: A Nationwide Retrospective Cohort Study.

This study aimed to evaluate the risk of uveitis, one of the most common ocular manifestations of COVID-19, in individuals with a history of uveitis and COVID-19 infection while discriminating the effects of COVID-19 infection and vaccinations. We analyzed nationwide data from 235,228 individuals with a history of uveitis prior to COVID-19 infection and evaluated incidences and hazard ratios (HRs) of post-COVID-19 uveitis for different post-infection periods, including early- (within 30 days) and delayed-onset ones. The cumulative incidences of post-infection uveitis at 3, 6, and 12 months were calculated as 8.5%, 11.8%, and 14.0%, respectively. The HR of post-COVID-19 uveitis was 1.21 (95% confidence interval [CI]: 1.07-1.37) and was particularly higher in the early-onset period (1.42, 95% CI: 1.24-1.61). Vaccinated individuals showed a modestly elevated risk of uveitis relative to pre-infection, while unvaccinated ones exhibited substantially higher risks in the early-onset period: the HR of post-infection uveitis before vaccination was 3.61 (95% CI: 1.35-9.66), whereas after vaccination, it was 1.21 (95% CI: 1.05-1.39). COVID-19 infection was associated with a higher risk of uveitis, which was mitigated by vaccination. Vigilance in the monitoring of uveitis is warranted for recently COVID-19-infected individuals with a history of uveitis, particularly unvaccinated individuals.

Effectiveness of BNT162b2 Against Infection, Symptomatic Infection, and Hospitalization Among Older Adults Aged ≥65 Years During the Delta Variant Predominance in Japan: The VENUS Study.

We evaluated the effectiveness of the BNT162b2 vaccine against infection, symptomatic infection, and hospitalization in older people during the Delta-predominant period (July 1 to September 30, 2021). We performed a population-based cohort study in an older adult population aged ≥65 years using data from the Vaccine Effectiveness, Networking, and Universal Safety Study conducted from January 1, 2019, to September 30, 2021, in Japan. We matched BNT162b2-vaccinated and -unvaccinated individuals in a 1:1 ratio on the date of vaccination of the vaccinated individual. We evaluated the effectiveness of the vaccine against infection, symptomatic infection, and coronavirus disease (COVID-19)-related hospitalization by comparing the vaccinated and unvaccinated groups. We estimated the risk ratio and risk difference using the Kaplan-Meier method with inverse probability weighting. The vaccine effectiveness was calculated as (1 - risk ratio) × 100%. The study included 203,574 matched pairs aged ≥65 years. At 7 days after the second dose, the vaccine effectiveness of BNT162b2 against infection, symptomatic infection, and hospitalization was 78.1% (95% confidence interval [CI], 65.2-87.8%), 79.1% (95% CI, 64.6-88.9%), and 93.5% (95% CI, 83.7-100%), respectively. BNT162b2 was highly effective against infection, symptomatic infection, and hospitalization in Japan's older adult population aged ≥65 years during the Delta-predominant period.

MRNA vaccines protect from the lung microvasculature injury and the capillary blood volume loss occurring in SARS-CoV-2 paucisymptomatic infections.

The reduction of lung capillary blood volume (Vc) had been identified as the microvascular injury mostly underlying the respiratory Long-COVID syndrome following post-COVID-19 pneumonia. The same kind of injury have been recently also found in several individuals after milder paucisymptomatic SARS-CoV-2 infections. Though current guidelines strongly recommend vac-cination, studies aimed to investigate the in vivo protection of anti-SARS-CoV-2 vaccines on lung microvascular targets still are missing to our best knowledge. to assess the protection of mRNA vaccines from the reduction of lung capillary blood volume (Vc) caused by pauci-symptomatic SARS.CoV-2 infections in vaccinated compared to unvaccinated individuals. Non-smoking individuals with recent paucisymptomatic SARS-CoV-2 infection were divided into vaccinated and unvaccinated groups. Lung function parameters, including single-breath diffusing capacity and microvascular blood volume, were compared between groups. fifty vaccinated and twenty-five unvaccinated well-matched individuals were studied. Differently than usual lung function parameters, only the single-breath simultaneous assessment of sDLCO, sDLNO/sDLCO ratio and Vc allowed to identify the occurrence of the lung microvascular injury with high sensitivity and specificity (p<0.001). mRNA vaccines proved to exert a high protection from the loss of lung capillary blood volume (Vc) induced by SARS.CoV-2 paucisymptomatic infections (p<0.001). The availability of this non-invasive investigational model should be regarded as a very helpful tool for assessing and comparing in vivo the protective effect of mRNA vaccines on the human microvascular structures of the deep lung.

A Qualitative Exploration of Factors Associated with COVID-19 Vaccine Uptake and Hesitancy in Selected Rural Communities in Kenya

Purpose: The post-pandemic management of COVID-19 infections and any emergent outbreaks is because this endemic disease remains a public health concern. Vaccine hesitancy may continue to hamper efforts to respond to any new disease outbreaks and future epidemics. This qualitative study aimed to explore the factors influencing COVID-19 vaccine acceptance and hesitancy in Kenya to gain deeper insights into this issue. Methods: This study was implemented in western Kenya using key informant interviews. Fourteen (14) key informants were purposively selected for this study. All interviews were transcribed and analyzed using thematic analysis. The interpretation of findings was conducted within the framework of the Health Belief Model. Key findings: Knowledge was a critical factor in combatting misinformation and fostering vaccine acceptance among participants in this study. Misinformation included rumors that the vaccine lowers immunity and was intended for population control. Cues to action included influence from political and opinion leaders and observing the loss of life among unvaccinated individuals. Perceived barriers to vaccine uptake included fear of vaccine safety, side effects, long waiting times at the time of our study, fear of contracting COVID-19 at vaccination sites, family/spousal influence on vaccine uptake and fear of the unknown with the vaccine. Conclusions: The findings from this study provide insight into areas for targeted strategies for managing COVID-19 vaccinations and future pandemics. Within the framework of the Health Belief Model, this study identified salient barriers and facilitators of COVID-19 vaccine hesitancy that may be helpful to inform future pandemic responses.

Vaccine Uptake and Intentions: Insights from a Texas Survey on Factors Influencing COVID-19 Vaccination Decisions.

The effectiveness of COVID-19 vaccines depends on widespread vaccine uptake. Employing a telephone-administered weighted survey with 19,502 participants, we examined the determinants of COVID-19 vaccine acceptance among adults in Texas. We used multiple regression analysis with LASSO-selected variables to identify factors associated with COVID-19 vaccine uptake and intentions to receive the vaccine among the unvaccinated. The prevalence of unvaccinated individuals (22%) was higher among those aged 18-39, males, White respondents, English speakers, uninsured individuals, those facing financial challenges, and individuals expressing no concern about contracting the illness. In a fully adjusted regression model, higher odds of being unvaccinated were observed among males (aOR 1.11), the uninsured (aOR 1.38), smokers (aOR 1.56), and those facing financial struggles (aOR 1.62). Conversely, Asians, Blacks, and Hispanics were less likely to be unvaccinated compared to Whites. Among the unvaccinated, factors associated with stronger intent to receive the vaccine included age (over 65 years), Black and Hispanic ethnicity, and perceived risk of infection. Hispanic individuals, the uninsured, those covered by public insurance, and those facing financial challenges were more likely to encounter barriers to vaccine receipt. These findings underscore the importance of devising tailored strategies, emphasizing nuanced approaches that account for demographic, socioeconomic, and attitudinal factors in vaccine distribution and public health interventions.

Impact of the COVID-19 vaccinations on economic outcomes and mental health services in the U.S

The development of vaccines has long been viewed as a critical public health tool to raise immunity against the COVID-19 virus and to reopen economic activities globally. Against this background, this study examines the impact of COVID-19 vaccinations on economic outcomes and mental health services in the U.S. We employed the Household Pulse Survey covering 549, 950 and 57, 892 vaccinated and unvaccinated individuals, respectively. For the causal analysis, we control the differences between the vaccinated and unvaccinated groups using propensity score matching (PSM) and augmented inverse probability weighting (AIPW) methods. Economic outcomes include whether individuals work on-site, telework or work from home, in-store shopping, job loss, or food sufficient. We also consider whether individuals experience mental health distress and receive mental health services as a potential outcome. The empirical results show that the probability of working on-site, in-store shopping, food sufficiency, and using mental health services are significantly higher among the recipients of the COVID-19 vaccines than non-recipients. We also find that the likelihood of teleworking and job loss decreased significantly among the recipients of the COVID-19 vaccine compared to non-recipients. The magnitude of the estimated impact across race and ethnic groups is mixed, which shows that vaccination effects are heterogeneous across the races/ethnic groups in the sample.