Number Of Vaccine Doses Research Articles

Effects of COVID-19 and pneumococcal conjugate vaccines on hospitalized older COVID-19 patients in Türkiye

Background: The COVID-19 vaccine, CoronaVac, and pneumococcal conjugate vaccine, PCV13, are part of Türkiye's adult immunization programme to reduce COVID-19 severity and mortality among older adults. Aim: To evaluate the effects of CoronaVac and PCV13 vaccines on hospitalized patients aged ≥ 65 years in Türkiye. Methods: This retrospective descriptive study included 365 patients aged ≥ 65 years admitted to the COVID-19 wards and intensive care unit of Şişli Hamidiye Etfal Training and Research Hospital in Türkiye between March and June 2021. We evaluated vaccine efficacy among patients at ≥ 14 days and < 14 days after the second dose. We analysed the data using SPSS version 20.0 and compared proportions in independent groups using χ2 test. P < 0.05 was considered statistically significant. Results: Intensive care unit admission was lower (25.3%) among patients vaccinated with CoronaVac than among unvaccinated patients (38.5%), and mortality rate was significantly lower (16.9% vs 32.7%) among vaccinated patients. Mortality decreased significantly with the number of vaccine doses. No significant relationship was found between PCV13 vaccination and mortality or intensive care unit admission, but mortality was lower among vaccinated patients. Conclusion: CoronaVac significantly reduced intensive care unit admissions and mortality among older COVID-19 patients. Although PCV13 did not show a significant reduction in mortality, its observed benefit supports continued pneumococcal vaccination among older populations.

Effectiveness of hepatitis A immunisation after paediatric liver transplantation: A retrospective observational analysis.

This retrospective study aimed to investigate the response to hepatitis A virus (HAV) immunisation following liver transplantation. We analysed, 234 vaccination records of 284 children who underwent liver transplantation between January 2003 and July 2021, including annual serological results. Of the 120 HAV-naïve patients, approximately 71% and 83% showed seroconversion after receiving one and two vaccine doses, respectively. The third dose increased the seroconversion rate to 93%. In multivariable logistic regression analysis, the number of vaccine doses and age at first vaccine dose were independently associated with seroconversion. In contrast, additional immunosuppression with mycophenolate mofetil (MMF) was negatively associated with seroconversion. In Cox regression analysis of all 96 seroconverted children, younger age at first vaccination and additional immunosuppression with either MMF or prednisolone were identified as independent risk factors for the early loss of HAV immunity. In summary, HAV immunisation with the three-dose vaccination series is recommended for paediatric liver transplant recipients. Antibody testing and booster vaccinations, if necessary, are recommended, especially for those living in endemic areas or with additional immunosuppressive treatments.

Booster vaccination and post-COVID-19 condition during the Omicron variant-dominant wave: a large population-based study.

The effect of the COVID-19 booster vaccination and the long-term consequences concerning preventing post-COVID-19 condition (PCC) remains unclear. We aimed to investigate the association of COVID-19 booster vaccination dose and vaccination timing before infection with the risk of PCC during the Omicron variant-dominant wave. This population-based study included patients confirmed with COVID-19 (extracted from the Health Center Real-time Information-sharing System) aged 20-69years, who were infected between 1 July and 31 August 2022. We used a self-report questionnaire to evaluate PCC and extracted information on vaccination from the municipal vaccine registry system. We calculated multiple propensity scores for COVID-19 vaccination status (unvaccinated, 1-2 doses and ≥3 doses) to control for baseline population differences. We then used a logistic regression model with inverse probability weighting to analyse the associations between the number of vaccine doses and the risk of PCC. Additionally, we conducted stratified analysis by gender and subgroup analysis for respiratory and neurological symptoms. Multivariable logistic regression was used to analyse the association between vaccination timing and PCC risk, adjusting for vaccination doses. Of the 7936 participants with COVID-19 (mean age 42.9years, 4553 women), 940 (11.8%) had at least 1 PCC. Compared with people unvaccinated, those vaccinated ≥3 times before the infection had a lower probability of PCC with the OR of 0.69 (95% CI: 0.53-0.90), although we detected no association with one or two doses. This association was present in women (≥3 doses vs. unvaccinated OR: 0.70, 95% CI: 0.51-0.95) but not in men. Those vaccinated ≥3 times had fewer neurological symptoms compared with those unvaccinated (OR: 0.61, 95% CI: 0.45-0.83); however, no significant association was found for respiratory symptoms. This study suggests that booster vaccination could lower the risk of PCC.

Abstract 4137534: Troponin Can Predict Late Gadolinium Enhancement on Cardiac MRI in COVID-19 Vaccine-Associated Myocarditis

Background/Aim: We previously reported that late gadolinium enhancement (LGE) on cardiac MRI (CMR) was as high as 82% in pediatric patients with COVID-19 vaccine-associated myocarditis (C-VAM) despite mild clinical symptoms and normal left ventricular function. As LGE can be a harbinger for future adverse events including arrhythmias, heart failure or sudden cardiac death, we sought to identify predictors for LGE in C-VAM, specifically assessing troponin as a screening marker for C-VAM patients at risk for myocardial scarring who could then be referred for a confirmatory CMR with LGE. Methods: In this longitudinal multicenter retrospective observational study across 38 U.S. member institutions of the M yocarditis A fter C OVID V accination (MACiV) study network, 333 patients with C-VAM based on CDC criteria were included from April 2021 to November 2022. Data collected included demographics, laboratory values, clinical and cardiac imaging characteristics and outcomes. Using logistic regression, troponin levels at presentation were assessed as a log transformed continuous variable and categorized into tertiles. Results: The C-VAM patients were predominantly white (67%) adolescent males (91%, 15.7± 2.8 years). There were 216/333 (65%) patients who had both a reported troponin value and had a CMR. On univariate analysis, elevated troponin increased the probability of having LGE (OR=1.29, 95% CI: 1.06, 1.58, p=0.012). Even after controlling for age, race, sex, number of vaccine doses and left ventricular ejection fraction (OR=1.32, 95% CI: 1.06, 1.65, p=0.013). Patients >15 years compared to those ≤15 years of age were 2.94 (95% CI: 1.28, 6.75, p=0.011) times more likely to have LGE at presentation. Patients with troponin levels in the highest tertile compared to lowest tertile were 2.66 times (95% CI: 1.04, 6.83, p=0.042) more likely to have LGE along with a greater involvement > 4 AHA myocardial segments with LGE (p=0.004) Conclusions: Higher troponin values are associated with presence of late gadolinium enhancement on cardiac MRI in patients with COVID-19 vaccine-associated myocarditis. Troponin levels at presentation may facilitate risk stratification and function as a screening tool to identify those C-VAM patients with the greatest likelihood of myocardial scarring, who may benefit from undergoing CMR for tissue characterization.

Attitudes toward mandatory vaccination and the COVID certificate as a function of vaccination status and risk perception: A vignette‐based study

AbstractIn January 2022, several vaccination policies were debated to address the Omicron outbreak in Belgium. Considering variability in risk perception and vaccine uptake, this study aimed to understand differences in support and expectations for four scenarios, ranging from relaxed to restrictive vaccination policies, to inform policymakers. Using an online survey, 12,670 participants (46% female; Mage = 45.9, SD = 13.38) reported their risk perception, number of vaccination doses (0/1, 2, 3 doses) as well as their support and several anticipated psychological outcomes for each scenario. Mixed model ANCOVA showed a pattern of preferential support for the relaxed scenario and more positive anticipated outcomes (general well‐being and government appraisals) compared to the restrictive policies, that were treated equivalently. An exception to this pattern was found when people were vaccinated with three doses and perceived high risk. Taken separately, risk perception and vaccination status were not sufficient to drive positive attitudes toward restrictive policies; only their interaction had an effect. Limitations include the self‐selected sample and the vignette methodology. The conjunct role of risk perception and vaccination status should be considered when discussing the introduction of restrictive vaccination policies. These findings inform vaccination strategies management during pandemics.

Clinical characteristics, depression, anxiety, and stress of medical workers during the COVID-19 pandemic: a cross-sectional survey.

Coronavirus disease 2019 (COVID-19) has an extremely high infection rate. This study aimed to investigate emotional states and COVID-19 infection of medical workers during the self-management strategy to COVID-19. Questionnaires were collected via an online questionnaire platform from 20 December 2022 to 19 January 2023, including demographic characteristics, number of vaccine doses, COVID-19 test results, occupation, attendant situations of workers, clinical symptoms, disease duration, and the Depression, Anxiety and Stress Scale 21. A total of 748 complete questionnaires were collected. The average age of participants was 33.61 ± 8.94 years, and 79.55% participants were female. The proportion of anxiety was significantly higher in the infection group (52.32%) than in the non-infection group (28.45%) (p < 0.001), as was the proportion of stress (41.47% vs. 31.90%, p = 0.046). Medical students (odds ratios (OR) 0.54, 95% confidence interval (CI) 0.31-0.93) and other staff (OR 0.63, 95% CI 0.40-0.98) had a lower risk for depression than doctors (p = 0.024), and attendant and infective situations of workers was the risk factor for depression (p = 0.007). Occupation (p = 0.029) and infected workers (p = 0.001) were related to anxiety. Infected attendant workers had a higher risk for stress (OR 1.97, 95% CI 1.12-3.48) than uninfected attendant workers (p = 0.019). Most medical workers infected with COVID-19 had emotional disorders during the COVID-19 pandemic. Attention and useful measures are suggested to support medical workers.

Analysis of serum IgM antibody and viral nucleic acid test results in measles and rubella cases in China from 2014 to 2023

Objective: To analyze the results of serum IgM antibody and viral nucleic acid testing in measles and rubella cases in China from 2014 to 2023. Methods: Surveillance data on measles and rubella during 2014-2023 were obtained from the Chinese Disease Prevention and Control Information System, and cases that underwent measles/rubella IgM antibody testing and viral nucleic acid testing were included in the study. Information on the number of cases, vaccination status, and laboratory test results was collected, and laboratory test results were compared among cases with different times of rash or onset and different doses of vaccination. Results: From 2014 to 2023, the total number of measles and rubella surveillance cases was 581 746, and the number of measles and rubella cases that underwent both IgM antibody and viral nucleic acid testing was 39 124 and 21 766, respectively, with a double-positive rate of IgM antibody and viral nucleic acid testing of 63.73% (for measles) and 41.68% (for rubella). The single-positive rate for IgM antibody was 21.12% (for measles) and 27.15% (for rubella). The single-positive rate for viral nucleic acid tests was 13.84% (for measles) and 28.19% (for rubella). According to different days of rash or onset (0-3, 4-5, 6-10 and >10), samples of 24 629 (62.95%) measles cases and 15 785 (72.52%) rubella cases were from within 3 days of rash or onset, and the single positive rate of viral nucleic acid detection was 16.90% (for measles) and 32.07% (for rubella). The single positive rate of IgM antibody increased gradually with the time of onset (measles: χ2trend=314.098, P<0.001, rubella: χ2trend=763.846, P<0.001), and reached 31.66% (for measles) and 53.12% (for rubella) after 10 days of rash or onset. Depending on the number of vaccination doses (1, 2,≥3), the single positive rate of viral nucleic acid detection ranged from 12.93% to 20.29% (for measles) and from 25.30% to 27.88% (for rubella). The single positive rate of IgM antibody detection ranged from 36.89% to 47.47% (for measles) and from 22.81 to 41.15% (for rubella). Conclusions: Combined testing of serum IgM antibody and viral nucleic acids could facilitate laboratory confirmation of measles and rubella cases and was also important for measles and rubella elimination efforts.

Seroprevalence of SARS-CoV-2 nucleocapsid antibody among sex workers during the 5th epidemic wave with Omicron variant in Chiang Mai, Thailand

ObjectivesTo investigate the seroprevalence of SARS-CoV-2 nucleocapsid antibodies (NC-Ab) in sex workers. MethodsA cross-sectional/observational study was conducted between March and December 2022 among sex workers living in Chiangmai, Thailand, aged over 18 years and who had engaged in sex work in the previous 12 months. Consenting individuals completed a questionnaire and had blood drawn. IgG-specific for SARS-CoV-2 nucleocapsid was assessed using Euroimmun anti-SARS-CoV-2 NCP ELISA (IgG). Results264 sex workers (52.3 % male) with a median age 31 years were included. The overall seroprevalence of SARS-CoV-2 NC-Ab was 42.4 % (44.2 % in males, 40.5 % in females). It was significantly higher among non-Thai than Thai sex workers (57.1 % vs. 37.1 %, p = 0.004) and among individuals who reported a history of COVID-19 as compared those who did not (54.9 % vs. 34.3 %, p = 0.036). NC-Ab seroprevalence did not differ by sex, age, receipt of COVID-19 vaccines, or the number of vaccine doses. SARS-CoV-2 NC-Ab seropositivity was significantly associated with being non-Thai, having monthly income >15,000 Baht, having received inactivated COVID-19 vaccines, and having been diagnosed with COVID-19. ConclusionsThis study shows a high seroprevalence of NC-Ab among sex workers in Chiangmai, Thailand during the fifth epidemic wave with Omicron variant. This may be due to combined effects of high transmissibility of the Omicron variant and high-risk behavior of those individuals. Specific health education interventions are needed for this specific population.

Reports of Batch-Dependent Suspected Adverse Events of the BNT162b2 mRNA COVID-19 Vaccine: Comparison of Results from Denmark and Sweden.

Background and Objective: An unexpected batch-dependent safety signal for the BNT162b2 mRNA COVID-19 vaccine was recently identified in a nationwide study from Denmark, but the generalizability of this finding is unknown. Therefore, we compared batch-dependent rates of suspected adverse events (SAEs) reported to national authorities in Denmark and Sweden. Materials and Methods: SAE and vaccine batch data were received from national authorities in Denmark and Sweden, and analyses of heterogeneity in the relationship between numbers of vaccine doses and SAEs per batch were performed, along with comparison of SAE rates and severities for batches that were shared between the two countries. Results: Significant batch-dependent heterogeneity was found in the number of SAEs per 1000 doses for both countries, with batches associated with high SAE rates detected in the early phase of the vaccination campaign and positive correlations observed between the two countries for the severity of SAEs from vaccine batches that they shared. Mild SAEs predominated in the batches used in the early part of the vaccination roll-out, where markedly higher SAE rates per 1000 doses in Denmark for the batches that were shared between the two countries suggested that a large proportion of these SAEs were under-reported in Sweden. Conclusions: The batch-dependent safety signal observed in Denmark and now confirmed in Sweden suggests that early commercial batches of BNT162b2 may have differed from those used later on, and these preliminary and hypothesis-generating results warrant further study.

Impact of the emergence of severe acute respiratory syndrome coronavirus 2 omicron variants on routine childhood immunization in Japan

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic disrupted routine childhood vaccination worldwide, especially at the beginning of the pandemic. After the emergence of variants of concern, particularly the Omicron variants, the number of COVID-19 cases significantly increased, especially in children. However, the impact of the Omicron variants on routine childhood vaccination is unknown. MethodsThis retrospective observational study collected data on vaccines included in the Japanese national immunization program (NIP) of children 15 years or younger between 2016 and 2022 in Niigata, Japan. During the study period, hepatitis B virus vaccine and rotavirus vaccines were introduced to the NIP in October 2016 and October 2020, respectively. The monthly number of vaccine doses per eligible child population between 2020 and 2022 (pandemic period) was compared to the average number of vaccine doses in the corresponding month between 2016 and 2019 (pre-pandemic period). The effect of 8 surges of COVID-19 patients on trends in routine childhood vaccination was also analyzed. ResultsThe numbers of doses during the pre-Omicron pandemic period were comparable to the values administered before the pandemic. However, after the emergence of the Omicron variants, and especially after the surge of Omicron variant BA.5 in 2022, the number of vaccine doses declined. The decline was notable in second doses of MR vaccine at age 5–6 years by − 9.6 % and diphtheria-tetanus vaccine at ages 11–12 years by − 14.1 %. ConclusionsRoutine childhood immunization was significantly affected by the emergence of the Omicron variants most likely due to the facts that more candidates and their guardians contracted COVID-19, or were required isolation for close contacts. The findings highlight the importance of continued monitoring to maintain high coverage of routine childhood immunizations for controlling vaccine preventable diseases. A follow-up study should investigate changes in the number of declined vaccine doses during Omicron variant predominance.

WITHDRAWN: Metformin alleviates inflammatory response and severity rate of COVID-19 infection in elderly individuals

ObjectiveTo evaluate the relationship between metformin and the outcome of COVID-19 infection. MethodsThe study included 413 patients with type 2 diabetes among the 5,217 patients enrolled in a COVID-19 study, and analyzed whether receiving metformin therapy prior to infection was associated with risk of ICU admission, development of pneumonia and length of hospital stay. The study also examined the correlation between metformin treatment and levels of IL-6, CRP, SF, L, CD4 at admission, as well as the increase in ORF1abCT after one week of hospitalization. ResultsThere were no differences in age, sex, BMI, comorbidities, number of vaccine doses or eGFR between patients receiving and not receiving metformin therapy. In the ICU group, the proportion of patients not receiving metformin was 92.5%, significantly higher than the 69.2% of patients not admitted to ICU (p=0.010). In the pneumonia group, the proportion of patients not receiving metformin was 78.6%, significantly higher than the 67.2% in the non-pneumonia group (p=0.020). Compared with patients receiving no treatment, those receiving metformin had a shorter hospital stay (12.1±5.9 days vs. 14.5±8.2 days, p=0.001). In the patients ≥60 years old, those receiving treatment had significantly lower levels of IL-6 (median, 12.3 pg/ml vs. 4.0 pg/ml, p=0.026) and significantly higher levels of Lymphocyte (median, 1.2×109/L vs. 1.4×109/L, p=0.015) compared with those not receiving treatment. However, for the patients under 60, there were no significant differences observed in IL-6 and Lymphocyte levels between those receiving treatment and those not. Conclusionmetformin can reduce the severity of COVID-19 infection and attenuate the inflammatory response associated with COVID-19 infection.

Factors influencing the utilisation of anti-HBs titre testing services among nursing students in Northwest Ghana: A cross-sectional study.

Understanding the impact of hepatitis B testing, vaccination, the number of vaccine doses, and socio-demographics on post-vaccination anti-HBs titre testing, is essential for hepatitis B prevention. The aim of the study was to determine the prevalence of hepatitis B testing, hepatitis B vaccination, number of vaccine doses received, socio-demographic characteristics, and their impact on anti-HBs titre testing among nursing students in Northwest Ghana. A stratified sample of 402 nursing students from Wa and Lawra nursing colleges in Ghana's Upper West Region was surveyed in November 2020 using an online cross-sectional design. STATA 13 was used to analyse the data, which described socio-demographics, hepatitis B testing, hepatitis B vaccination, and post-vaccination anti-HBs titre testing with frequencies and percentages. Hierarchical binary logistic regression models were used to investigate the relationships between post-vaccination anti-HBs titre testing and hepatitis B testing, vaccination, the number of vaccine doses, and their socio-demographics. The study discovered that while hepatitis B testing was high (89.0%), rates for hepatitis B vaccination (72.1%), obtaining the recommended vaccine doses (59.5%), and post-vaccination anti-HBs titre testing (19.4%) were lower. Nursing students who accepted hepatitis B vaccination were significantly more likely to undergo anti-HBs titre testing [aOR = 12.34; 95% CI = 1.80-84.54; p < 0.05]. Those who received ≥ 3 vaccine doses were over 8 times more likely to utilise anti-HBs titre testing [aOR = 8.31; 95% CI = 2.73-25.34; p < 0.001]. Wa NTC students were 74% less likely to access anti-HBs titre testing [aOR = 0.26; 95% CI = 0.15-0.47; p < 0.001]. Students with parents who had tertiary education were significantly more likely to undergo anti-HBs titre testing [aOR = 2.50; 95% CI = 1.42-4.42; p < 0.01]. The study reveals high hepatitis B testing but low vaccination rates, emphasizing the need for required vaccine doses and post-vaccination anti-HBs testing. Key predictors include hepatitis B vaccination, ≥3 doses, Wa NTC enrollment, and parental education. The study advocates mandatory testing, vaccination, and affordable access to anti-HBs titre testing. Unvaccinated students, those with <3 doses, Wa NTC attendees, and those with lower parental education for nursing school admission should be prioritised.

Side effects of COVID-19 vaccines in paediatric patients: a review systematic and meta-analysis protocol

IntroductionThe paediatric population represents a quarter of the world’s population, and like adult patients, they have also suffered immeasurably from the SARS-CoV-2 pandemic. Immunisation is an effective strategy for reducing...

Could Less Be More? Accounting for Fractional-Dose Regimens and Different Number of Vaccine Doses When Measuring the Impact of the RTS,S/AS01E Malaria Vaccine.

The RTS,S/AS01E (RTS,S) malaria vaccine is recommended for children in malaria endemic areas. This phase 2b trial evaluates RTS,S fractional- and full-dose regimens in Ghana and Kenya. In total, 1500 children aged 5-17 months were randomized (1:1:1:1:1) to receive RTS,S or rabies control vaccine. RTS,S groups received 2 full RTS,S doses at months 0 and 1 and either full (groups R012-20, R012-14-26) or fractional doses (one-fifth; groups Fx012-14-26, Fx017-20-32). At month 32 post-dose 1, vaccine efficacy against clinical malaria (all episodes) ranged from 38% (R012-20; 95% confidence interval [CI]: 24%-49%) to 53% (R012-14-26; 95% CI: 42%-62%). Vaccine impact (cumulative number of cases averted/1000 children vaccinated) was 1344 (R012-20), 2450 (R012-14-26), 2273 (Fx012-14-26), and 2112 (Fx017-20-32). To account for differences in vaccine volume (fractional vs full dose; post hoc analysis), we estimated cases averted/1000 RTS,S full-dose equivalents: 336 (R012-20), 490 (R012-14-26), 874 (Fx012-14-26), and 880 (Fx017-20-32). Vaccine efficacy was similar across RTS,S groups. Vaccine impact accounting for full-dose equivalence suggests that using fractional-dose regimens could be a viable dose-sparing strategy. If maintained through trial end, these observations underscore the means to reduce cost per regimen thus maximizing impact and optimizing supply. NCT03276962 (ClinicalTrials.gov).

Effectiveness of tixagevimab/cilgavimab (Evusheld) in antiCD20‑treated patients with multiple sclerosis and neuromyelitis optica spectrum disorder

BackgroundAntiCD20 therapy, such as rituximab, ocrelizumab, or ofatumumab, effectively treats patients with multiple sclerosis (pwMS) or neuromyelitis optica spectrum disorder (pwNMOSD) but negatively affects the humoral immune response to COVID-19 vaccination. One strategy to protect these patients is using tixagevimab/cilgavimab (T/C) as pre-exposure prophylaxis. This study aimed to evaluate the effect of T/C on the incidence of COVID-19 in pwMS and pwNMOSD. MethodsData in this observational cohort study were collected in two Czech MS centres through ReMuS registry between March 1, 2020 and December 31, 2022. Adult pwMS and pwNMOSD who were (1) treated with antiCD20 therapy at least six months before T/C administration, or at least from February 1, 2022 in the control group; (2) were already on antiCD20 therapy at the time of vaccination or COVID-19 infection; and (3) were on antiCD20 therapy at least 100 days after T/C, or at least 90 days after August 1, 2022 in the control group, were included. Analysis was performed using frequency-based (propensity score matching) and Bayesian statistical methods (informative and non-informative priors). ResultsUsing propensity score matching 1:1, 47 patients who received T/C (mean age 45.7 years, median disease duration 12.5 years) were matched with those who did not receive T/C (n = 341; mean age 46.6 years, median disease duration 11.4 years) based on age, MS/NMOSD duration, and number of vaccine doses. None of the T/C patients and three in the control matched group, developed COVID-19 between 10 and 100 days after receiving T/C, August 1, 2022, respectively. The frequency of COVID-19 was not significantly different between groups (p = 0.242). Due to the low number of patients, a Bayesian analysis was also added. Using a non-informative Bayesian prior, the median relative risk of COVID-19 after T/C was 7.6 % (95 % CrI 0.02–115.9 %). The posterior probability of risk difference lower than zero was 96.4 %. Using an informative prior (based on the registration study of Evusheld), the median relative risk of COVID-19 after T/C was 20.2 % (95 % CI 8.4–43.8 %). The posterior probability of the risk difference lower than zero was 100 %. ConclusionThis work highlights the possible good efficacy of T/C in antiCD20-treated pwMS and pwNMSOD. Based on Bayesian analysis with an informative prior, the T/C group's risk of COVID-19 infection was approximately 20.2 % of the control group's risk. However, given the low frequency of COVID-19, the results of this pilot analysis must be interpreted with caution.

Changes in the Adaptive Cellular Repertoire after Infection with Different SARS-CoV-2 VOCs in a Cohort of Vaccinated Healthcare Workers.

Currently approved vaccines are highly effective in protecting against hospitalization and severe COVID-19 infections. How pre-existing immunity responds to new variants with mutated antigens is crucial information for elucidating the functional interplay between antibodies and B and T cell responses during infection with new SARS-CoV-2 variants. In this study, we monitored the dynamics and persistence of the immune response versus different SARS-CoV-2 variants of concern that emerged during the pandemic period (2021-2022) in a cohort of vaccinated healthcare workers, who experienced breakthrough infection in the Pre-Delta, Delta, and Omicron waves. We evaluated both the humoral and cell-mediated responses after infection. We also evaluated the anti-SARS-CoV-2 antibodies levels produced by infection in comparison with those produced after vaccination. Our results highlighted that the immune response against the Delta VOC mainly involved an adaptive humoral and switched memory B cells component, even 3 months after the last vaccine dose, conversely showing a high percentage of depleted adaptive T cells. Omicron infections triggered a consistent production of non-vaccine-associated anti-N antibodies, probably to balance the spike epitope immune escape mechanisms. Our results suggest a direct dependence between the VOC and different humoral and B and T cell balances in the post-infection period, despite the administration of a different number of vaccine doses and the elapsed time since the last vaccination.

Long-Term Effectiveness and Durability of COVID-19 Vaccination Among Patients With Inflammatory Bowel Disease

Background and AimsCOVID-19 vaccination prevents severe disease in most patients with inflammatory bowel disease (IBD), but immunosuppressive medications can blunt serologic response. We followed adults with IBD for >1 year post–COVID-19 vaccination to describe factors associated with SARS-CoV-2 infection after vaccination, evaluate for a protective SARS-CoV-2 antibody level, characterize SARS-CoV-2 antibody persistence, and identify factors associated with humoral immune response durability. MethodsUsing a prospective cohort of COVID-19 immunized adults with IBD, we analyzed factors associated with SARS-CoV-2 infection after vaccination. We evaluated for an association between SARS-CoV-2 antibody level 12 weeks postvaccination and subsequent SARS-CoV-2 infection and assessed for a threshold of protection using receiver-operating characteristic curve analysis. We then conducted a separate analysis evaluating factors associated with persistence of SARS-CoV-2 antibodies 52 weeks postimmunization. ResultsAlmost half (43%) of 1869 participants developed COVID-19 after vaccination, but most infections were mild, and <1% required hospitalization. Older age and corticosteroid use were associated with a decreased risk of SARS-CoV-2 infection postvaccination (50–59 years of age vs 18–29 years of age: adjusted hazard ratio, 0.57; 95% confidence interval, 0.44–0.74; steroid users vs nonusers: adjusted hazard ratio, 0.58; 95% confidence interval, 0.39–0.87). Most (98%) participants had detectable antibody levels at 52 weeks postvaccination. Antibody levels at 12 weeks and number of vaccine doses were positively associated with higher antibody levels at 52 weeks, while anti-tumor necrosis factor α therapy was negatively associated. ConclusionsCOVID-19 vaccination generates an effective and durable protective response for the vast majority of adults with IBD, including vulnerable populations such as corticosteroid users and older individuals. Patients with IBD benefit from COVID-19 booster vaccination.

Is Epistemic Trust relevant for Vaccine Hesitancy? A study during the Covid-19 pandemic

Vaccine hesitancy and conspiracy beliefs are social issues of growing concern which have arisen particularly during the COVID-19 pandemic. The aim of this study was to investigate the multifaceted relationship between a hesitant attitude towards vaccination, conspiracy thinking, fear of infection, and the dimensions of epistemic trust, mistrust, and credulity. 297 Italian adult participants completed an online survey during the pan-demic time frame which included self-report questionnaires that measured the variables of interest. Group differences pertaining to prior vaccination behavior in scores of con-spiracy beliefs about vaccines and vaccine hesitancy were explored. A negative associa-tion was found between years of education and both vaccine hesitancy and conspiracy beliefs about vaccines, and a positive one with epistemic trust; higher education may protect the individual from misinformation and help in discerning between real knowledge and fake or imprecise news. A mediation model was developed between ep-istemic stance, vaccine conspiracy belief, vaccine hesitancy, and COVID-19-specific variables: the affective dimension (fear of contagion) and the behavioral one (number of vaccine doses). The model demonstrates how certain structural characteristics, such as epistemic credulity and skepticism towards vaccine benefits, may indirectly affect the number of COVID-19 vaccine doses taken through fear of contracting the virus. The re-sults support the value of exploring vaccine hesitancy and conspiracy beliefs in relation to epistemic trust dimensions, specifically in the post-pandemic era, and are discussed in light of the recent literature.

COVID-19 Vaccination and Women's Menstrual Cycle: A Cross-sectional Study Performed

Background: After widespread vaccination against COVID-19, a number of unknown complications were reported, including changes in the menstrual cycle. Objectives: Considering the limited information available on this subject, this study was carried out with the aim of studying the prevalence of menstrual disorders in women following COVID-19 vaccination. Methods: This cross-sectional study was performed in 2022 on 400 women of reproductive age who had received at least 2 doses of the COVID-19 vaccines. The participants were chosen from health centers in the city of Asadabad of Hamedan Province in Iran using the convenience sampling method. The research tool was a researcher-made questionnaire that investigated demographics and changes in the menstrual cycle. Data analysis was carried out using descriptive statistics (frequency and percentage) and inferential statistics (chi-square and Fisher's exact tests). Results: The findings showed that 36.3, 42.5, and 48.01% of the participants experienced menstrual disorders after the first, second, and third doses of vaccination, respectively. Significant relationships were observed between the number of vaccination doses and menstrual disorders (P ≤ 0.001). Furthermore, there were correlations between menstrual disorders and the type of administered vaccine in the first (P = 0.003) and third (P ≤ 0.001) doses. Conclusions: In this study, a number of menstrual complications were observed in women after the administration of the COVID-19 vaccine, and such complications were intensified by an increase in the number of vaccines administered. Since this study was cross-sectional, it cannot be said with certainty whether the administration of the COVID-19 vaccine results in menstrual disorders or not. For this purpose, there is a need for more case-control or prospective studies.

P395 The frequency of SARS-CoV-2 infection and the impact of vaccination on the disease morbidity in Polish pediatric patients with Inflammatory Bowel Disease treated with biologic therapies

Abstract Background Little is known about morbidity of Covid-19 infection in pediatric patients with inflammatory bowel diseases (IBD) treated with biologic medications. The aim of this study was to evaluate the frequency of SARS-CoV-2 infection in children with IBD who received biologic therapies. Methods A prospective, observational cohort study to evaluate coronavirus disease 2019 (COVID-19) vaccination state, and its effect on the disease course among pediatric patients with IBD. The questionnaire included information concerning numbers of vaccine doses, patients’ medication and disease activity. Disease flare was defined by worsening IBD symptoms and change in IBD medications. Outcomes were stratified by vaccine type and IBD medication classes. Results A total of 320 children with IBD, 169 with Crohn’s disease (CD)-52,8%, 150 with ulcerative colitis (UC) - 46,9%, 1 unclassified -0,3%, responded to the questionnaire concerning COVI-19 vaccination. In our cohort 141 (49,7%) patients received biologic therapy: 13 patients (9,2%) adalimumab (ADA), 54 (38,3%) infliximab (IFX), 27 (19,1%) vedolizumasb (vedo), 29 (20,6%) ustekinumab (ust), 6 - vedo + ADA (4,3%), 1 - IFX + vedo (0,7%), 11 - ust + ADA (7,8%). 32 (22,7%) patients had COVID-19 infection during biological therapy (ust 6- 4,3%, vedo 7- 5,0%, ada 2-1,4%, ifx 12- 8,5%, ust + ada 2- 1,4%, vedo + ada 3- 2,1%). Among the patients on biologic treatment suffering from COVID-19, 25 (78,1%) children had mild course of the infection, 4 moderate (12,5%), 2 severe (6,3%), and 1 unknown (3,1%). A total of 127 (39,7%) patients received at least 1 COVID-19 vaccine, and among them 8 (6,3%) patients who received 1 dose of COVID-19 vaccine got the infection during biologic therapy. In our group, 193 (60,3%) patients have not been vaccinated against COVI-19, and 24 (12,4%) suffered from the disease during biologic therapy. Conclusion Based on the outcomes from our questionnaire concerning COVID-19 vaccination state on the large cohort of pediatric patients with IBD, we conclude that unvaccinated patients get sick more often than vaccinated ones, and that the use of biological treatment has no impact the frequency of covid infections or their course.