Statistical Assessment of the Effectiveness of Multiple COVID-19 Vaccinations on Daily Confirmed Cases in Seoul City.

This study investigates the effectiveness of multiple COVID-19 vaccinations on daily confirmed cases in Seoul City. Utilizing comprehensive data on vaccinated individuals and confirmed cases sourced from the official website of the Korean Ministry of the Interior and Safety, we conducted detailed statistical analyses to assess the impact of each vaccination dose. The study covers data from April 21, 2021, to September 29, 2022. Statistical multiple linear regression was employed to analyze the relationship between daily confirmed cases (positive outcomes from PCR tests) and multiple vaccine doses, using p-values as the criteria for determining the effectiveness of each dose. The analysis included data from four vaccination doses. The analysis reveals that the first, second, and third doses of the COVID-19 vaccines have a statistically significant positive effect associated with the daily confirmed cases. However, the study finds that the fourth dose does not show a statistically significant impact on the reduction of daily confirmed cases. This suggests that while the initial three doses are crucial for establishing and maintaining high levels of immunity, the incremental benefit of subsequent doses may diminish.

Seroprevalence of SARS-CoV-2 and risk factors for infection among children in Uganda: a serial cross-sectional study.

Background: Understanding COVID-19's impact on children is vital for public health policy, yet age-specific data is scarce, especially in Uganda. This study examines SARS-CoV-2 seroprevalence and risk factors among Ugandan children at two timepoints, along with COVID-19-related knowledge and practices in households, including adult vaccination status. Methods: Baseline surveys were conducted in 12 communities from April to May 2021 (post-Alpha wave) and follow-up surveys in 32 communities from November 2021 to March 2022 (Omicron wave). Household questionnaires and blood samples were collected to test for malaria by microscopy and for SARS-CoV-2 using a Luminex assay. Seroprevalence was estimated at both the survey and community level. Mixed-effects logistic regression models assessed the association between individual and household factors and SARS-CoV-2 seropositivity in children, adjusting for household clustering. Results: More households reported disruptions in daily life at baseline compared to follow-up, though economic impacts lingered. By the follow-up survey, 52.7% of adults had received at least one COVID-19 vaccine dose. Overall seroprevalence in children was higher at follow-up compared to baseline (71.6% versus 19.2%, p < 0.001). Seroprevalence in children ranged across communities from 6-37% at baseline and 50-90% at follow-up. At baseline, children from the poorest households were more likely to be infected. Increasing age remained the only consistent risk factor for SARS-CoV-2 seroconversion at both timepoints. Conclusions: Results indicate that a larger number of children were infected by the Delta and Omicron waves of COVID-19 compared to the Alpha wave. This study is the largest seroprevalence survey in children in Uganda, providing evidence that most children were infected with SARS-CoV-2 before the vaccine was widely available to pediatric populations. Pediatric infections were vastly underreported by case counts, highlighting the importance of seroprevalence surveys in assessing disease burden when testing and reporting rates are limited and many cases are mild or asymptomatic.

Analyzing the 7C psychological antecedents of vaccine acceptance throughout the COVID-19 pandemic among healthcare sector workers in France: A repeated cross-sectional study (CappVac-Cov).

BACKGROUND: Across various stages of the COVID-19 pandemic and related vaccine recommendations in France, we assessed the association of the 7C-psychological antecedents with vaccine uptake/intention for booster vaccination among healthcare-sector workers (HCSWs). We also assessed whether 7C-antecedent profiles changed over time. METHODOLOGY: The Research Group for the Prevention of Occupational Infections in Healthcare Workers (GERES) conducted three repeated web-surveys which were disseminated by email chain-referral among HCSWs throughout France. The questionnaires waves took place: July-November 2021, February-March 2022 and January-March 2023 (P2, P3 and P4). We also reanalysed data from a prior similar study conducted late 2020-early 2021 (Moirangthem et al. (2022)) (P1). To evaluate the association of 7C-items with vaccine uptake-intention for future vaccination, we estimated adjusted prevalence ratios (aPR) using robust variance Poisson regression. We report the 7C-item population attributable loss in vaccine intention. RESULTS: The four surveys (P1-P4) encompassed 5234, 339, 351 and 437 participants. At earlier stages of the vaccine campaign, the principal antecedents of vaccine intention were favorable perception of vaccination benefit-risk-balance (BRB) (vs. unfavorable, aPR: 2.32), reactance to employer encouragement for vaccination (motivates vs. dissuades-me, aPR:2.23), vaccine confidence (vs. not-being-confident, aPR: 1.71) and social conformism towards vaccination (favorable vs. skeptical opinion in private environment, aPR: 1.33). Under a vaccine mandate for HCSWs, only perceiving vaccination as a collective action was associated with current vaccine status (agree vs. disagree, aPR: 2.19). At later stages of the epidemic, hypothetical booster vaccine intentions were strongly associated with BRB perception (favorable vs. unfavorable, aPR: 2.07) and perceiving vaccination as a collective action (agree vs. disagree, aPR: 1.69). Fearing a severe side effect from vaccination decreased population vaccine intention by 26.2 %. CONCLUSION: Our results suggest that both 7C-antecedents and their association with vaccine behaviour can change over time, and underscore the importance of assuring confidence in vaccine safety.

COVID-19 vaccination and long COVID among 50 years older and above European: The role of chronic multimorbidity.

BACKGROUND AND AIMS: We aimed to explore the association between coronavirus disease-19 (COVID-19) vaccination and long COVID according to the status of chronic multimobidity. METHODS: A total of 1913 participants were recruited in the cross-sectional study on the basis of the Survey of Health and Retirement in Europe. COVID-19 vaccination was defined as vaccination within the last 12 months. Chronic multimorbidity was defined as history of 2 + chronic disease. The study outcome was long COVID during the 12-month follow-up. Multivariable logistic models were performed to estimate the influence of chronic multimorbidity on the association of vaccination with long COVID. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated. RESULTS: Chronic multimorbidity significantly modified the association of COVID-19 vaccination with long COVID (Pinteraction = 0.024). The rates of study outcome were significantly lower among vaccinated participants in the chronic multimorbidity subgroup, but not in the other subgroup. Multivariable odds ratios (95 % confidence intervals) of study outcome for unvaccination vs. vaccination were 1.494 (1.013-2.203) in those with multimorbidity and 0.915 (0.654-1.280) in those without multimorbidity, respectively. Adding COVID-19 vaccination to a model containing conventional risk factors significantly improved risk reclassification for study outcome among those with chronic multimobidity (continuous NRI was 25.39 % [P = 0.002] and IDI was 0.42 % [P = 0.075]) CONCLUSION: An inverse association of COVID-19 vaccination with long COVID was found among participants with chronic multimorbidity, but not among those without chronic multimorbidity. Chronic multimorbidity might expand the influence of unvaccination on developing long COVID among European aged ≥50 years.

Predicting COVID-19 vaccine uptake: Comparing the health belief model and theory of planned behavior.

The COVID-19 outbreak has had a significant impact on the global health landscape, underscoring the crucial role that vaccinations play in achieving herd immunity and reducing the effects of pandemics. Given the importance of this issue, it is imperative to gain a deeper understanding of the various factors that influence individuals' decisions to seek vaccination. This study aimed to compare the prediction level of the Health Belief Model (HBM), the Theory of Planned Behavior (TPB), and a combined model in explaining the intention of adults to receive COVID-19 immunization. A cross-sectional online survey was conducted among adults (n = 505) in Saudi Arabia. The survey contained variables related to the HBM and TPB. The prediction level of the two models as well as a combined model were evaluated utilizing Structural Equation Modeling (SEM). Among the recruited 505 participants, 88% fell within the 18 to 30 age range, and 54.5% were male. The proposed HBM model accounted for 68% of the variation in intention, whereas the TPB model explained 78.2% of the variation in COVID-19 vaccination intention. The combined model showed greater explanatory power (82%). The variables of susceptibility (ß = 0.20, p < .001), severity (ß = 0.49, p < .001), advantages (ß = 0.63, p < .001), and obstacles (ß = - 0.24, p < .001), perceptions of behavioral control (ß = 1.58, p < .001) and attitudes (ß = 0.44, p < .001) were found to significantly predict increased vaccination intentions in the combined model. However, the subjective norm construct did not significantly predict vaccination intentions (ß = 0.06, p = .34). The TPB has greater explanatory power than the HBM in predicting the intention to obtain COVID-19 vaccination. However, the combined model showed a greater prediction level. Understanding and identifying people's perceived health beliefs and practices is critical for developing successful COVID-19 intervention methods.

Heterologous and homologous COVID-19 mRNA vaccination schemes for induction of basic immunity show similar immunogenicity regarding long-term spike-specific cellular immunity in healthcare workers.

Healthcare workers (HCWs) are recommended to receive at least three spike-antigen exposures to generate basic immunity and to mediate herd protection of vulnerable patients. So far, less attention has been put on the cellular immune response induced by homologous (three BTN162b2mRNA doses) or heterologous (mRNA-1273 as third dose building on two BTN162bmRNA doses) and the immunological impact of breakthrough infections (BTIs). Therefore, in 356 vaccinated HCWs with or without BTIs the Anti-SARS-CoV-2-Spike-IgG concentrations and avidities and B- and T-cell-reactivity against SARS-CoV-2-Spike-S1- and Nucleocapsid-antigens were assessed with Interferon-gamma-ELISpot and by flow-cytometry. HCWs who had hybrid immunity due to BTIs exhibited strong T-cell-reactivity against the Spike-S1-antigen. A lasso regression model revealed a significant reduction in T-cell immune responses among smokers (p < 0.0001), with less significant impact observed for age, sex, heterologous vaccination, body-mass-index, Anti-Nucleocapsid T-cell reactivity, days since last COVID-19-immunization, and Anti-SARS-CoV-2-Spike-IgG. Although subgroup analysis revealed higher Anti-SARS-CoV-2-Spike-IgG after heterologous vaccination, similar cellular reactivity and percentages of Spike-reactive T- and B-cells were found between homologous and heterologous vaccination. Anti-SARS-CoV-2-Spike-IgG concentrations and avidity significantly correlated with activated T-cells. CD4 + and CD8 + responses correlated with each other. A strong long-term cellular immune response should be considered as baseline for recommendations of booster doses in HCWs with prioritization of smokers. HCWs presented significant T-cellular reactivity towards Spike-S1-antigen with particularly strong responses in hybrid immunized HCWs who had BTIs. HCWs without BTI presented similar percentages of Spike-specific B- and T-cells between homologous or heterologous vaccination indicating similar immunogenicity for both mRNA vaccines, BNT162b2mRNA and mRNA-1273.

Quantifying Disparities in COVID-19 Vaccination Rates by Rural and Urban Areas: Cross-Sectional Observational Study.

BACKGROUND: Vaccination plays an important role in preventing COVID-19 infection and reducing the severity of the disease. There are usually differences in vaccination rates between urban and rural areas. Measuring these differences can aid in developing more coordinated and sustainable solutions. This information also serves as a reference for the prevention and control of emerging infectious diseases in the future. OBJECTIVE: This study aims to assess the current coverage rate and influencing factors of COVID-19 (second booster) vaccination among Chinese residents, as well as the disparities between urban and rural areas in China. METHODS: This cross-sectional study used a stratified random sampling approach to select representative samples from 11 communities and 10 villages in eastern (Changzhou), central (Zhengzhou), western (Xining), and northeast (Mudanjiang) Mainland China from February 1 to February 18, 2023. The questionnaires were developed by experienced epidemiologists and contained the following: sociodemographic information, health conditions, vaccine-related information, information related to the Protective Motivation Theory (PMT), and the level of trust in the health care system. Vaccination rates among the participants were evaluated based on self-reported information provided. Binary logistic regression models were performed to explore influencing factors of vaccination among urban and rural participants. Urban-rural disparities in the vaccination rate were assessed using propensity score matching (PSM). RESULTS: A total of 5780 participants were included, with 53.04% (3066/5780) being female. The vaccination rate was 12.18% (704/5780; 95% CI 11.34-13.02) in the total sample, 13.76% (341/2478; 95% CI 12.40-15.12) among the rural participants, and 10.99% (363/3302; 95% CI 9.93-12.06) among the urban participants. For rural participants, self-reported health condition, self-efficacy, educational level, vaccine knowledge, susceptibility, benefits, and trust in the health care system were independent factors associated with vaccination (all P＜.05). For urban participants, chronic conditions, COVID-19 infection, subjective community level, vaccine knowledge, self-efficacy, and trust in the health care system were independent factors associated with vaccination (all P＜.05). PSM analysis uncovered a 3.42% difference in vaccination rates between urban and rural participants. CONCLUSIONS: The fourth COVID-19 vaccination coverage rate (second booster) among the Chinese population was extremely low, significantly lower than the previous vaccine coverage rate. Given that COVID-19 infection is still prevalent at low levels, efforts should focus on enhancing self-efficacy to expand the vaccine coverage rate among the Chinese population. For rural residents, building awareness of the vaccine's benefits and improving their overall health status should be prioritized. In urban areas, a larger proportion of people with COVID-19 and patients with chronic illness should be vaccinated.

Association between a past history of nausea and vomiting during pregnancy and fever after the BNT162b2 COVID-19 vaccination.

PURPOSE: Nausea and vomiting during pregnancy (NVP) are common among pregnant women and can be severe enough to require hospitalization. However, the mechanism underlying NVP pathogenesis remains unclear. This study examined factors associated with adverse events after vaccination, including a past history of NVP. METHODS: A questionnaire-based survey was completed by non-pregnant women working at Nagasaki University Hospital who received two doses of the BNT162b2 coronavirus disease 2019 (COVID-19) vaccine. This study primarily examined the association between a past history of NVP and post-vaccination fever, as fever was determined to be the most objective and reliable indicator of the surveyed adverse events. RESULTS: Multivariate logistic regression analysis showed that post-vaccination fever was more strongly associated with a past history of NVP (odds ratio, 1.88; 95% confidence interval, 1.16-3.07) than either age (0.73; 0.56-0.96) or weight (0.85; 0.70-1.15), which were previously considered to be highly associated with the incidence of adverse events following COVID-19 vaccination. CONCLUSION: These results suggest an involvement of a similar pathological condition in developing NVP and post-vaccination fever.

Fertility outcomes in women undergoing Assisted Reproductive Treatments after COVID-19 vaccination: A prospective cohort study.

BACKGROUND: Vaccination against Coronavirus-19 disease (COVID-19) was widely administered from 2021 onwards. There is little information on how this vaccine affected fertility after assisted-reproductive-technology (ART). The aim of this study therefore was to determine if COVID-19 vaccination or time-since-vaccination influenced ART outcomes. MATERIALS AND METHODS: In this prospective cohort study, 502 oocyte-retrieval-cycles and 582 subsequent embryo- transfer-cycles were grouped based on COVID-19 vaccine status of the female partner into those with no-exposure, 1-dose and ≥2-dose exposure. Within the exposed cohort, time-since-last-vaccination to embryotransfer- cycle (Ttr) was calculated in days. Main outcomes were mean-total-utilizable-embryos, mean-oocyteutilization- rates and cumulative-ongoing-pregnancy-rates per oocyte-retrieval-cycle, and ongoing-pregnancy and pregnancy-loss-rates per embryo-transfer cycle. The Beta-coefficient (ß) was calculated using linear regression for mean-total-utilizable-embryos and mean-oocyte-utilization-rates and adjusted-odds-ratio (OR) was calculated for cumulative-ongoing-pregnancy-rates, ongoing-pregnancy and pregnancy-loss-rates using binomial logistic regression. Influence of T(tr) on embryo-transfer outcomes was estimated using receiver-operator-curve (ROC) analysis and cut-offs determined that influenced embryo-transfer outcomes. RESULTS: Mean-total-utilizable-embryos and mean-oocyte-utilization-rate per oocyte-retrieval-cycle in no-exposure, 1-dose and ≥2 dose were 2.7 ± 1.8 vs. 2.5 ± 1.9 vs. 2.7 ± 2.0, P=0.78, (ß=0.42, 95% confidence-interval (CI)=0.15 to 0.69) and 21.2 ± 13.2 vs. 25.1 ± 19.0 vs. 26.7 ± 18.8, P=0.08, (ß=3.94, 95% CI=1.26 to 6.23) respectively. Ongoing-pregnancy-rates and pregnancy-loss-rates per embryo-transfer-cycle were 27.3% vs. 24.4% vs. 32.5% (aOR=1.38, 95% CI=0.3-5.6, P=0.52), and 13.6% vs. 13.4% vs. 15.2%, (aOR=0.97, 95% CI=0.18-5.2, P=0.97) respectively. Cumulative-ongoing-pregnancy-rates per oocyte-retrieval-cycle were 36.5% vs. 34.5% vs. 35.5% (aOR=1.53, 95% CI=0.57 to 4.07, P=0.35). Median T(tr) was 146 days (IQR: 80-220). T(tr) negatively affected ongoing pregnancy rates for intervals <60 days (AUC=0.59, 95% CI=0.54-0.66, P<0.01). For T(tr) >60 vs. <60 days, the aOR for ongoing-pregnancy-per-embryo-transfer-cycle was 2.85 (95% CI=1.50-5.46, P<0.01). CONCLUSION: Covid-19 vaccination does not negatively influence embryological-outcomes or cumulative-ongoing-pregnancies after ART-treatments. Duration since vaccination may have a weak negative effect on embryo-transfer-outcomes performed within 60 days.

Effects of vaccination on COVID-19 infection symptoms in multiple sclerosis patients.

Background: Patients with multiple sclerosis (MS) are at higher risk of having infections due to receiving disease modifying therapies. The current study was conducted among Iranian MS patients who had experienced at least one episode of COVID-19 infection in order to evaluate the effects of COVID-19 vaccination on symptoms of their infection. Data on demographic information, MS characteristics, COVID-19 infection details, and vaccination status were collected. Statistical analyses, were performed to evaluate the association between vaccination and symptoms of COVID-19 infection. Methods: This cross-sectional study was conducted on confirmed MS patients. Demographic data and COVID-19 related symptoms were gathered via an online questionnaire. Confirmation of patients' who declared to be vaccinated was checked by their COVID-19 vaccination card. Results: A total of 236 MS patients participated in the study. The majority were female (79.7%), with a mean age of 36.1 ± 7.9 years. Among the participants, 72.5% had received the COVID-19 vaccine before their first episode of COVID-19 infection. The analysis showed a significant difference in the incidence of respiratory symptoms (P-value: 0.01) and headache (P-value: 0.04) between vaccinated and non-vaccinated individuals. Logistic regression analysis revealed that vaccinated MS patients had lower odds of developing respiratory symptoms (OR:0.29, 95% CI: 0.16 to 0.53, P-value<0.001) or headache (OR: 0.50, 95% CI: 0.25 to 0.98, P-value: 0.04) during their next COVID-19 infection episode. Moreover, MS patients who were receiving immunosuppressive drugs were less likely to have respiratory symptoms (OR:0.35, 95% CI: 0.16 to 0.77, P-value:0.009) but not headache (OR: 0.69, 95% CI: 0.30 to 1.60, P-value: 0.39). Conclusion: COVID-19 vaccination can reduce the incidence of respiratory symptoms and headaches in MS patients during COVID-19 infection episodes. Additionally, patients who are receiving immunosuppressive drugs may benefit from COVID-19 vaccination.

Acute pancreatitis complicated with diabetic ketoacidosis following COVID-19 mRNA vaccination: a case report.

Objective: Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, COVID-19 vaccination has substantially reduced mortality and hospitalization rates worldwide, with rare adverse events reported in clinical settings. Herein, we present a case of acute pancreatitis complicated by diabetic ketoacidosis (DKA) following the third COVID-19 vaccination dose. Patient: A 72-year-old male with a history of diabetes mellitus developed generalized fatigue, mild epigastric pain, nausea, and frequent vomiting after receiving the COVID-19 vaccine. Results: Blood analysis revealed elevated levels of pancreatic enzymes, hyperglycemia, and acidemia. Computed tomography revealed evidence of acute pancreatitis, leading to a diagnosis of both DKA and acute pancreatitis. Treatment with a large volume of saline and intravenous insulin improved both DKA and acute pancreatitis. After a thorough examination, no other factors capable of causing acute pancreatitis were identified. Hence, we concluded that acute pancreatitis was induced by COVID-19 vaccination. Conclusion: Acute pancreatitis is a rare but potentially life-threatening adverse event associated with COVID-19 vaccination. Delaying the treatment or diagnosis of acute pancreatitis can increase mortality risk in patients with both acute pancreatitis and DKA. Hence, it is crucial for healthcare professionals to consider the potential occurrence of acute pancreatitis and DKA following COVID-19 vaccination.

Dynamic evolution of COVID-19 vaccine hesitancy over 2021-2023 among Chinese population: Repeated nationwide cross-sectional study.

Globally, the rollout of COVID-19 vaccine had been faced with a significant barrier in the form of vaccine hesitancy. This study adopts a multi-stage perspective to explore the prevalence and determinants of COVID-19 vaccine hesitancy, focusing on their dynamic evolutionary features. Guided by the integrated framework of the 3Cs model (complacency, confidence, and convenience) and the EAH model (environmental, agent, and host), this study conducted three repeated national cross-sectional surveys. These surveys carried out from July 2021 to February 2023 across mainland China, targeted individuals aged 18 and older. They were strategically timed to coincide with three critical vaccination phases: universal coverage (stage 1), partial coverage (stage 2), and key population coverage (stage 3). From 2021 to 2023, the surveys examined sample sizes of 29 925, 6659, and 5407, respectively. The COVID-19 vaccine hesitation rates increased from 8.39% in 2021 to 29.72% in 2023. Urban residency, chronic condition, and low trust in vaccine developer contributed to significant COVID-19 vaccine hesitancy across the pandemic. Negative correlations between the intensity of vaccination policies and vaccine hesitancy, and positive correlations between vaccine hesitancy and long COVID, were confirmed. This study provides insights for designing future effective vaccination programs for emerging vaccine-preventable infectious X diseases.

The negative impact of misinformation and vaccine conspiracy on COVID-19 vaccine uptake and attitudes among the general public in Iraq.

Background: Vaccine hesitancy is a major barrier to infectious disease control. Previous studies showed high rates of COVID-19 vaccine hesitancy in the Middle East. The current study aimed to investigate the attitudes towards COVID-19 vaccination and COVID-19 vaccine uptake among adult population in Iraq. Methods: This self-administered survey-based study was conducted in August-September 2022. The survey instrument assessed participants' demographics, attitudes to COVID-19 vaccination, beliefs in COVID-19 misinformation, vaccine conspiracy beliefs, and sources of information regarding the vaccine. Results: The study sample comprised a total of 2544 individuals, with the majority reporting the uptake of at least one dose of COVID-19 vaccination (n = 2226, 87.5 %). Positive attitudes towards COVID-19 vaccination were expressed by the majority of participants (n = 1966, 77.3 %), while neutral and negative attitudes were expressed by 345 (13.6 %) and 233 (9.2 %) participants, respectively. Factors associated with positive attitudes towards COVID-19 vaccination in multivariate analysis included disbelief in COVID-19 misinformation and disagreement with vaccine conspiracies. Higher COVID-19 vaccine uptake was significantly associated with previous history of COVID-19 infection, higher income, residence outside the Capital, disbelief in COVID-19 misinformation, disagreement with vaccine conspiracies, and reliance on reputable information sources. Conclusion: COVID-19 vaccine coverage was high among the participants, with a majority having positive attitudes towards COVID-19 vaccination. Disbelief in COVID-19 misinformation and disagreement with vaccine conspiracies were correlated with positive vaccine attitudes and higher vaccine uptake. These insights can inform targeted interventions to enhance vaccination campaigns.

Temporal Trends in SARS-CoV-2 Antibody Levels Among COVID-19 Patients in Kerala During the First Wave and Pre-vaccination Period.

BACKGROUND: The SARS-CoV-2 virus interacts with host cells through the S1 domain of its spike protein. This study measures the IgG immune response to this domain in COVID-19 patients from Kerala, India, and explores its association with various health factors. METHODS: A cohort of 258 COVID-19 patients was analyzed for IgG antibodies targeting the S1 spike protein domain. The temporal pattern of the IgG response and its correlation with hospitalization needs, intensive care, and pre-existing conditions such as diabetes, hypertension, and coronary artery disease were assessed. RESULTS: A significant IgG response (76.4%) was detected, indicating robust immune activation post-infection. The IgG levels peaked between two to four and four to eight weeks post-infection, with a notable increase at 12 weeks, hinting at possible secondary exposure or an immune memory response. No correlation was found between IgG levels and the presence of diabetes mellitus, hypertension, or coronary artery disease. However, higher IgG responses correlated with the severity of the infection, as seen in patients requiring hospitalization or intensive care. CONCLUSIONS: The IgG response to the S1 spike protein domain serves as a potential marker of immune activation in COVID-19. It reflects the body's defense mechanism against the virus and may predict disease severity and outcomes. The findings suggest that IgG levels could be indicative of the viral load, inflammatory response, and possibly the likelihood of protection against reinfection.

Vaccination against COVID-19 among healthcare workers as a cocoon strategy for people living with HIV.

Introduction: Healthcare professionals working in infectious disease units are often engaged in the care of patients with HIV infection. A cocoon vaccination strategy may protect those who are immunocompromised from a severe course of COVID-19. Methods: The research was conducted between January 2021 and June 2022. The study participants were 450 healthcare workers (HCWs) from the Hospital for Infectious Diseases in Warsaw who were vaccinated against COVID-19 with the BNT162b2 mRNA vaccine (Pfizer-BioNTech) -, thefirst available type of vaccine in Poland. Sera were collected according to the schedule of the study. Statistical analyses were performed with non-parametric tests: Wilcoxon's test was used to compare dependent numerical variables, and Fisher's exact test and the Chi-squared test to compare categorical variables. A p value of <0.05 was considered statistically significant. Results: Among the 450 HCWs working in the Hospital for Infectious Diseases in Warsaw 412 (91,5 %) were vaccinated against COVID-19. In total 170 (41,3 %) vaccinated HCWs were included in the final analysis. Their median age was 51 years [interquartile range (IQR): 41-60 years] and median body mass index (BMI) was 25.10 [IQR: 22.68-29.03]. Most of the cohort consisted of women (n = 137, 80.59 %), with the majority working directly with patients (n = 137, 73.21 %). It was found that as early as 14 days after the second dose of the vaccine, 100 % of the study participants achieved a positive result for SARS CoV-2 S-RBD antibodies. There were 168 subjects who had had a COVID-19 diagnosis before entering study and after vaccination 65 HCWs was diagnosed with COVID-19. Conclusions: Due to the fact that people living with HIV with severe immunodeficiency may have an incomplete immune response to COVID vaccination and be at risk of a severe course of the disease, the cocoon strategy of vaccinating medical personnel may be beneficial for these patients.

Case report: A case of unilateral combined central retinal vein occlusion, incomplete central retinal artery occlusion, and papillitis following a third dose of COVID-19 vaccination.

Purpose: The aim of this study was to present a case of severe visual loss due to retinal arteriovenous occlusion and papillitis in one eye following vaccination against coronavirus disease (COVID-19). Methods: A 45-year-old man undergoing treatment for hypertension had severely reduced visual acuity in the right eye 1 day after receiving a third dose of a COVID-19 vaccine manufactured by Moderna. Clinical examination showed that the best-corrected visual acuity in the right eye was counting fingers. Other findings included circumferential retinal hemorrhage, perimacular ischemic color, severe macular edema, and severe optic disc swelling, indicating the presence of central retinal vein occlusion, incomplete central retinal artery occlusion, and papillitis. Based on the possibility of post-vaccination inflammation and/or abnormal immune response, three courses of steroid pulse therapy were administered, and the visual acuity slightly improved to 20/1,000. Results: Three months after the onset of symptoms, macular edema disappeared; conversely, retinal thinning of the macula and extensive non-perfusion areas mainly on the nasal side were noted. Conclusion: The findings in this case suggest that inflammation and abnormal immune response after receiving a COVID-19 vaccination may lead to combined retinal arteriovenous occlusion and papillitis.

Uptake of COVID-19 vaccination among community-dwelling individuals receiving healthcare for substance use disorder and major mental illness: a matched retrospective cohort study.

Introduction: Patients with major mental illness (MMI) and substance use disorders (SUD) face barriers in accessing healthcare. In this population-based retrospective cohort study, we investigated the uptake of COVID-19 vaccination in Ontario, Canada among community-dwelling individuals receiving healthcare for major mental illness (MMI) and/or substance use disorders (SUD), comparing them to matched general population controls. Methods: Using linked health administrative data, we identified 337,290 individuals receiving healthcare for MMI and/or SUD as of 14 December 2020, matched by age, sex, and residential geography to controls without such healthcare. Follow-up extended until 31 December 2022 to document vaccination events. Results: Overall, individuals receiving healthcare for MMI and/or SUD (N = 337,290) had a slightly lower uptake of first (cumulative incidence 82.45% vs. 86.44%; hazard ratio [HR] 0.83 [95% CI 0.82-0.83]) and second dose (78.82% vs. 84.93%; HR 0.77 [95% CI 0.77-0.78]) compared to matched controls. Individuals receiving healthcare for MMI only (n = 146,399) had a similar uptake of first (87.96% vs. 87.59%; HR 0.97 [95% CI 0.96-0.98]) and second dose (86.09% vs. 86.05%, HR 0.94 [95% CI 0.93-0.95]). By contrast, individuals receiving healthcare for SUD only (n = 156,785) or MMI and SUD (n = 34,106) had significantly lower uptake of the first (SUD 78.14% vs. 85.74%; HR 0.73 [95% CI 0.72-0.73]; MMI & SUD 78.43% vs. 84.74%; HR 0.76 [95% CI 0.75-0.77]) and second doses (SUD 73.12% vs. 84.17%; HR 0.66 [95% CI 0.65-0.66]; MMI & SUD 73.48% vs. 82.93%; HR 0.68 [95% CI 0.67-0.69]). Discussion: These findings suggest that effective strategies to increase vaccination uptake for future COVID-19 and other emerging infectious diseases among community-dwelling people with SUD are needed.

University Students' Vaccination Intention after the Fifth Wave of the COVID-19 Outbreak in Hong Kong: Inspiration from a Health Belief Model.

The fifth wave of COVID-19, driven by the Omicron variant, started to surge in Hong Kong in December 2021. Previous studies have shown that younger adults, compared to older adults, are vulnerable to increased risks of side effects after vaccination. However, little is known about the COVID-19 vaccination behavior among younger adults, especially university students, in Hong Kong. Therefore, the present online survey study aimed to investigate the predictors of COVID-19 vaccination intention among university students in Hong Kong using the Health Belief Model (HBM) as a framework. Two other potential predictors, the previous influenza vaccine uptake frequency and the Hong Kong SAR government vaccination lottery program, were also examined. The intention to receive another dose of the COVID-19 vaccine was low (36.4%). Multivariate binomial logistic regression analysis showed that, after controlling for demographic and baseline characteristics, the perceived susceptibility (OR = 2.98, CI = 1.18-7.53) and previous influenza vaccine uptake frequency (OR = 1.54, CI = 1.08-2.19) significantly and positively predicted the COVID-19 vaccination intention. However, the government vaccination lottery program (i.e., wining prizes for being vaccinated) (OR = 0.87, CI = 0.34-2.26) was not a significant motivator of COVID-19 vaccination. Future public health campaigns should focus on the individual susceptibility to COVID-19 and past influenza vaccination history to promote increased vaccination uptake among university students.

An overview and single-arm meta-analysis of immune-mediated adverse events following COVID-19 vaccination.

Background: We conducted an overview to assess immune adverse effects associated with the COVID-19 vaccine, guiding safer choices and providing evidence-based information to clinicians. Methods: Forty-three studies on adverse effects of vaccines were reviewed from PubMed, Embase, and Web of Science. Single-arm meta-analyses estimated summary effects, incidence, presentation, etc. An overview using single-arm meta-analysis and reported the findings following the guidelines outlined in the 'Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) specifically focusing on myocarditis and thrombosis. After screening 2,591 articles, 42 studies met the inclusion criteria. Methodological quality was evaluated using AMSTAR 2. Disagreements were resolved via consensus. Data analysis utilized a random-effects model in R software to estimate incidence rates of selected adverse events. Results: After removing 1,198 duplicates and screening out irrelevant articles from a total of 2,591, we included 42 studies. Adverse reactions to vaccinations include myocarditis, thrombosis, skin reactions, GBS, etc. thrombosis and myocarditis are the most dangerous diseases associated with vaccination. Myocarditis occurred in 6% of Vector vaccine recipients, compared to 61% of mRNA vaccine recipients. Thrombosis was more common after Vector vaccination (91%) than after mRNA vaccination (9%). Furthermore, eight studies conducted anti-PF4 antibody tests and yielded a positivity rate of 67%. Meta-analysis showed that among all patients with Vaccine-induced Thrombotic Thrombocytopenia, cerebral venous sinus thrombosis occurred in 66%, and intracranial hemorrhage occurred in 43%. The rates of deep vein thrombosis and pulmonary thromboembolism in vaccinated patients were 13% and 23%, respectively, with a pooled case fatality rate of 30%. Conclusion: The results of this overview indicate the majority of adverse reactions are self-limiting and require minimal intervention, while rare occurrences such as myocarditis and thrombosis pose a potentially fatal threat.

Association between adverse events after COVID-19 vaccination and anti-SARS-CoV-2 antibody concentrations, the Netherlands, May 2021 to November 2022: a population-based prospective cohort study.

BackgroundNon-severe adverse events (AE) including pain at injection site or fever are common after COVID-19 vaccination.AimTo describe determinants of AE after COVID-19 vaccination and investigate the association between AE and pre- and post-vaccination antibody concentrations.MethodsParticipants of an ongoing prospective cohort study (VASCO) completed a questionnaire on AE within 2 months after vaccination and provided 6 monthly serum samples during May 2021-November 2022. Logistic regression analyses were performed to investigate AE determinants after mRNA vaccination, including pre-vaccination Ig antibody concentrations against the SARS-CoV-2 spike protein receptor binding domain. Multivariable linear regression was performed in SARS-CoV-2-naive participants to assess the association between AE and log-transformed antibody concentrations 3-8 weeks after mRNA vaccination.ResultsWe received 47,947 completed AE questionnaires by 28,032 participants. In 42% and 34% of questionnaires, injection site and systemic AE were reported, respectively. In 2.2% of questionnaires, participants sought medical attention. AE were reported more frequently by women, younger participants (< 60 years), participants with medical risk conditions and Spikevax recipients (vs Comirnaty). Higher pre-vaccination antibody concentrations were associated with higher incidence of systemic AE after the second and third dose, but not with injection site AE or AE for which medical attention was sought. Any AE after the third dose was associated with higher post-vaccination antibody concentrations (geometric mean concentration ratio: 1.38; 95% CI: 1.23-1.54).ConclusionsOur study suggests that high pre-vaccination antibody levels are associated with AE, and experiencing AE may be a marker for higher antibody response to vaccination.