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19 pages, 794 KB  
Article
Implementation and Adherence of a Custom Mobile Application for Anonymous Bidirectional Communication Among Nearly 4000 Participants: Insights from the Longitudinal RisCoin Study
by Ana Zhelyazkova, Sibylle Koletzko, Kristina Adorjan, Anna Schrimf, Stefanie Völk, Leandra Koletzko, Alexandra Fabry-Said, Andreas Osterman, Irina Badell, Marc Eden, Alexander Choukér, Marina Tuschen, Berthold Koletzko, Yuntao Hao, Luke Tu, Helga P. Török, Sven P. Wichert and Thu Giang Le Thi
Infect. Dis. Rep. 2025, 17(4), 88; https://doi.org/10.3390/idr17040088 - 24 Jul 2025
Viewed by 1580
Abstract
Background: The longitudinal RisCoin study investigated risk factors for COVID-19 vaccination failure among healthcare workers (HCWs) and patients with inflammatory bowel disease (IBD) at a University Hospital in Germany. Since the hospital served as the study sponsor and employer of the HCW, [...] Read more.
Background: The longitudinal RisCoin study investigated risk factors for COVID-19 vaccination failure among healthcare workers (HCWs) and patients with inflammatory bowel disease (IBD) at a University Hospital in Germany. Since the hospital served as the study sponsor and employer of the HCW, we implemented a custom mobile application. We aimed to evaluate the implementation, adherence, benefits, and limitations of this study’s app. Methods: The app allowed secure data collection through questionnaires, disseminated serological results, and managed bidirectional communication. Access was double-pseudonymized and irreversibly anonymized six months after enrollment. Download frequency, login events, and questionnaire submissions between October 2021 and December 2022 were analyzed. Multivariable logistic regression identified factors associated with app adherence. Results: Of the 3979 participants with app access, 3622 (91%) used the app; out of these, 1016 (28%) were “adherent users” (≥12 submitted questionnaires). App adherence significantly increased with age. Among HCW, adherent users were more likely to be non-smokers (p < 0.001), working as administrators or nursing staff vs. physicians (p < 0.001), vaccinated against influenza (p < 0.001), and had not travelled abroad in the past year (p < 0.001). IBD patients exposed to SARS-CoV-2 (p = 0.0133) and those with adverse events following the second COVID-19 vaccination (p = 0.0171) were more likely adherent app users. Despite technical issues causing dropout or non-adherence, the app served as a secure solution for cohort management and longitudinal data collection. Discussion: App-based cohort management enabled continuous data acquisition and individualized care while providing flexibility and anonymity for the study team and participants. App usability, technical issues, and cohort characteristics need to be thoroughly considered prior to implementation to optimize usage and adherence in clinical research. Full article
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22 pages, 3669 KB  
Article
Factors Associated with Impaired Humoral Immune Response to mRNA Vaccines in Patients with Inflammatory Bowel Disease: A Matched-Cohort Analysis from the RisCoin Study
by Katarina Csollarova, Leandra Koletzko, Thu Giang Le Thi, Paul R. Wratil, Ana Zhelyazkova, Simone Breiteneicher, Marcel Stern, Gaia Lupoli, Tobias Schwerd, Alexander Choukér, Veit Hornung, Oliver T. Keppler, Kristina Adorjan, Helga Paula Török and Sibylle Koletzko
Vaccines 2025, 13(7), 673; https://doi.org/10.3390/vaccines13070673 - 23 Jun 2025
Cited by 1 | Viewed by 1391
Abstract
Background/Objectives: The SARS-CoV-2 pandemic challenged patients with inflammatory bowel disease (IBD) under immunosuppressive therapies. We used data from the RisCoin cohort to investigate factors associated with a poor immune response to mRNA vaccination in these patients. Methods: From 4115 RisCoin participants, we [...] Read more.
Background/Objectives: The SARS-CoV-2 pandemic challenged patients with inflammatory bowel disease (IBD) under immunosuppressive therapies. We used data from the RisCoin cohort to investigate factors associated with a poor immune response to mRNA vaccination in these patients. Methods: From 4115 RisCoin participants, we matched 110 IBD patients by age and time interval since the second mRNA vaccination with 306 healthcare workers (HCW) without comorbidities (HCW-healthy) and 292 with medical conditions (HCW-plus); all were SARS-CoV-2 infection naïve. Basic questionnaires collected data on medication, COVID-19 vaccinations and side-effects, dietary patterns, lifestyle factors, and self-perceived stress. Main outcomes included anti-spike immunoglobulin levels and antibody-mediated live-virus neutralization immunity (NT) to the Omicron BA.1 variant (threshold NT ≥ 10 defined as IC50 values ≥1:10 serum dilution) after the second (baseline) and third vaccinations. Results: At baseline, IBD patients treated with anti-TNF but not those under vedolizumab or ustekinumab therapy had lower anti-spike levels compared to HCW-healthy and HCW-plus (166 versus 1384 and 1258 BAU/mL, respectively; p < 0.0001). Anti-TNF compared to vedolizumab/ustekinumab-treated patients reached NT titers above threshold in 17% versus 64%, respectively, and HCW-subgroups in 73% and 79% (all p < 0.0001). Current smokers showed a four to five times increased risk for non-neutralizing immunity compared to non-smokers. After the third vaccination, NT titers did not reach threshold in 15% anti-TNF compared to 5% vedolizumab/ustekinumab-treated patients and none of HCW (p < 0.01). Patients with IBD reported fewer clinical symptoms after vaccination. Perceived stress was not increased. Conclusions: Our findings support individualized schedules for mRNA-based vaccines in IBD patients with different immunosuppressive therapies and enforcement of non-smoking. Full article
(This article belongs to the Section COVID-19 Vaccines and Vaccination)
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10 pages, 230 KB  
Article
Persistence of Anti-HB Antibodies in Healthcare Trainees: The Impact of Childhood Versus Adolescent Vaccination
by Luca Di Giampaolo, Luca Coppeta, Paola Borrelli, Piergiorgio Astolfi, Andrea Resta, Lucia Loffredo, Flavia Di Menno Di Bucchianico, Rocco Mangifesta, Lorenzo Ippoliti and Cristiana Ferrari
Vaccines 2025, 13(6), 562; https://doi.org/10.3390/vaccines13060562 - 26 May 2025
Cited by 1 | Viewed by 1200
Abstract
Background: Hepatitis B virus (HBV) infection remains a significant occupational health concern for healthcare workers (HCWs), including trainees exposed to biological risks. Although vaccination is the most effective preventive measure, the persistence of immunity over time and the need for booster doses remain [...] Read more.
Background: Hepatitis B virus (HBV) infection remains a significant occupational health concern for healthcare workers (HCWs), including trainees exposed to biological risks. Although vaccination is the most effective preventive measure, the persistence of immunity over time and the need for booster doses remain subjects of debate. Objective: The present study aims to assess the prevalence of protective anti-HB antibody titers among healthcare trainees at the “SS Annunziata” Hospital in Chieti, comparing those vaccinated in infancy with those vaccinated during adolescence. Methods: A retrospective observational study was conducted on 2028 healthcare trainees from 2021 to 2024. Participants were divided into two groups based on vaccination timing: infancy (PED group) and adolescence (ADO group). Serological tests were performed to measure anti-HB titers, with a protective threshold set at ≥10 IU/L. Statistical analyses were conducted to evaluate differences in immunity persistence between the two groups. The results showed that the overall prevalence of protective anti-HB titers was 50.7%, with significant differences between the PED and ADO groups. Protective immunity was observed in 79.2% of individuals vaccinated during adolescence, compared to 44.6% of those vaccinated in infancy (p < 0.001). No significant differences in antibody persistence were found between males and females. Notably, 92.4% of participants with non-protective titers received a booster dose within two months of testing. Conclusions: The study confirms a significant decline in anti-HB titers over time among individuals vaccinated in infancy, suggesting a potential need for booster doses later in adulthood. The high adherence to vaccination recommendations among healthcare trainees is a promising finding, reinforcing the importance of continuous education and immunization programmes in healthcare settings. Further research, including longitudinal studies and additional HBV biomarkers, is necessary to optimize vaccination strategies and long-term immunity monitoring in HCWs. Full article
22 pages, 3022 KB  
Article
Circulating Antibodies Against Common Cold Coronaviruses Do Not Interfere with Immune Responses to Primary or Booster SARS-CoV-2 mRNA Vaccines
by Bindu Adhikari, Eugene M. Oltz, Richard J. Gumina, Maryssa K. Kick, Linda J. Saif and Anastasia N. Vlasova
Vaccines 2025, 13(5), 547; https://doi.org/10.3390/vaccines13050547 - 21 May 2025
Viewed by 1775
Abstract
Background: Pre-existing cross-reactive antibodies (Abs) against common cold coronaviruses (CCCoVs) have been hypothesized to influence the immune responses to SARS-CoV-2 vaccine-induced Ab responses. Methods: Serum samples from healthy healthcare workers (HCWs, n = 64) receiving mRNA vaccines were collected at seven time points: [...] Read more.
Background: Pre-existing cross-reactive antibodies (Abs) against common cold coronaviruses (CCCoVs) have been hypothesized to influence the immune responses to SARS-CoV-2 vaccine-induced Ab responses. Methods: Serum samples from healthy healthcare workers (HCWs, n = 64) receiving mRNA vaccines were collected at seven time points: pre-COVID-19-vaccination (Pre), post-first dose (Vax1), post-second dose (Vax2), and 6-, 9-, 12-, and 15-months post-Vax2. Booster vaccine doses (n = 23) were received 1–80 days prior to the 9 m sample collection time point. We used peptide-based enzyme-linked immunosorbent assays (ELISAs) to measure SARS-CoV-2/CCCoV-specific IgG/IgA/IgM and SARS-CoV-2 IgG4 (associated with immune tolerance) Ab levels in the HCW serum samples. Additionally, we measured Epstein–Barr/influenza A (unrelated pathogens) virus-specific IgG Ab levels. Results: We observed that vaccination significantly increased SARS-CoV-2 IgG Ab levels at the Vax1 (p ≤ 0.0001) and Vax2 (p ≤ 0.0001) time points compared to Pre-Vax. These Ab levels declined at 6 months post-vaccination but increased again following the booster vaccine dose around the 9-month post-Vax2 time point in a cohort (n = 23) of the HCWs. However, this increase was modest compared to those induced by the primary vaccine series. Interestingly, a moderate but continuous increase in SARS-CoV-2 S IgG4 Ab levels was observed throughout this study, becoming statistically significant by the 15-month time point (p = 0.03). Further, a significant increase in CCCoV IgG (but not IgA/IgM) Ab levels was observed at the Vax1 time point, suggestive of cross-reactive or non-specific immune responses. Finally, we observed no negative correlation between the levels of pre-existing CCCoV-specific Abs and the vaccine-induced Ab response (Vax1/Vax2). Conclusions: Pre-existing CCCoV Abs do not interfere with the development of vaccine-induced immunity. However, vaccine-associated Abs wane over time, which may be associated with the increasing IgG4 Ab response. Full article
(This article belongs to the Section COVID-19 Vaccines and Vaccination)
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17 pages, 3334 KB  
Article
Longitudinal Surveillance of COVID-19 Antibodies in Pediatric Healthcare Workers
by Dunia Hatabah, Sneh Lata Gupta, Grace Mantus, Patrick Sullivan, Stacy Heilman, Andres Camacho-Gonzalez, Deborah Leake, Mimi Le, Mark Griffiths, Carson Norwood, Samuel Shih, Rawan Korman, Giorgi Maziashvili, Chris A. Rees, Laura Benedit, Bridget A. Wynn, Mehul Suthar, Miriam B. Vos, Jens Wrammert and Claudia R. Morris
Vaccines 2025, 13(2), 163; https://doi.org/10.3390/vaccines13020163 - 7 Feb 2025
Viewed by 1571
Abstract
Background: Vaccines against COVID-19 target the spike protein. There is minimal information on longitudinal COVID-19 immune profiling in recovered versus naïve and vaccinated versus non-vaccinated healthcare workers (HCWs). Methods: This is a prospective longitudinal observational cohort of pediatric HCWs (pHCWs) conducted during 2020–2022 [...] Read more.
Background: Vaccines against COVID-19 target the spike protein. There is minimal information on longitudinal COVID-19 immune profiling in recovered versus naïve and vaccinated versus non-vaccinated healthcare workers (HCWs). Methods: This is a prospective longitudinal observational cohort of pediatric HCWs (pHCWs) conducted during 2020–2022 at an academic center, exploring the impact of COVID-19 vaccination on immunoglobulin G (IgG) antibody titers over time and cross-reactivity with other coronaviruses, including SARS-CoV-1, MERS-CoV, and seasonal coronaviruses (HCoV-HKU1 and HCoV-OC43). Results: A total of 642 pHCWs initially enrolled, and 337 participants had repeat IgG titers measured post-vaccine and post-booster. Most participants were female, median age range of 31–40 years. Anti-spike was higher in all vaccinated individuals versus non-vaccinated (p < 0.0001) and naïve versus infected (p < 0.0001). A single dose of vaccine was sufficient to attain maximum titers in recovered participants versus naïve who received both doses of vaccine. Anti-spike titers dropped significantly at 9 months after the primary series, whereas sustained anti-spike titers were observed at 9 months post-booster. Conclusions: All vaccinated pHCWs developed antibodies to spike. COVID-19 infection and/or vaccination yielded antibodies that cross-reacted to SARS-CoV-1, MERS-CoV, HCoV-HKU1, and HCoV-OC43. Anti-spike titers were more durable post-booster compared to the primary series. Longitudinal immune profiling of COVID-19 responses provides vital data to shape public health policies, optimize vaccine strategies, and strengthen pandemic preparedness. Full article
(This article belongs to the Special Issue 2nd Edition of Antibody Response to Infection and Vaccination)
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14 pages, 806 KB  
Systematic Review
The Global Burden of Absenteeism Related to COVID-19 Vaccine Side Effects Among Healthcare Workers: A Systematic Review and Meta-Analysis
by Marios Politis, Georgios Rachiotis, Varvara A. Mouchtouri and Christos Hadjichristodoulou
Vaccines 2024, 12(10), 1196; https://doi.org/10.3390/vaccines12101196 - 19 Oct 2024
Cited by 1 | Viewed by 2661
Abstract
Background: A rise in absenteeism among healthcare workers (HCWs) was recorded during the COVID-19 pandemic, mostly attributed to SARS-CoV-2 infections. However, evidence suggests that COVID-19 vaccine-related side effects may have also contributed to absenteeism during this period. This study aimed to synthesize the [...] Read more.
Background: A rise in absenteeism among healthcare workers (HCWs) was recorded during the COVID-19 pandemic, mostly attributed to SARS-CoV-2 infections. However, evidence suggests that COVID-19 vaccine-related side effects may have also contributed to absenteeism during this period. This study aimed to synthesize the evidence on the prevalence of absenteeism related to COVID-19 vaccine side effects among HCWs. Methods: The inclusion criteria for this review were original quantitative studies of any design, written in English, that addressed absenteeism related to the side effects of COVID-19 vaccines among HCWs. Four databases (PubMed, Scopus, Embase, and the Web of Science) were searched for eligible articles on 7 June 2024. The risk of bias was assessed using the Newcastle–Ottawa scale. Narrative synthesis and a meta-analysis were used to synthesize the evidence. Results: Nineteen observational studies with 96,786 participants were included. The pooled prevalence of absenteeism related to COVID-19 vaccine side effects was 17% (95% CI: 13–20%), while 83% (95% CI: 80–87%) of the vaccination events did not lead in any absenteeism. Study design, sex, vaccination dose, region, and vaccine type were identified as significant sources of heterogeneity. Conclusions: A non-negligible proportion of HCWs were absent from work after reporting side effects of the COVID-19 vaccine. Various demographic factors should be considered in future vaccination schedules for HCWs to potentially decrease the burden of absenteeism related to vaccine side effects. As most studies included self-reported questionnaire data, our results may be limited due to a recall bias. Other: The protocol of the study was preregistered in the PROSPERO database (CRD42024552517). Full article
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15 pages, 2002 KB  
Article
B Cells Isolated from Individuals Who Do Not Respond to the HBV Vaccine Are Characterized by Higher DNA Methylation-Estimated Aging Compared to Responders
by Katarzyna Malgorzata Kwiatkowska, Simona Anticoli, Stefano Salvioli, Luciano Calzari, Davide Gentilini, Christian Albano, Reparata Rosa Di Prinzio, Salvatore Zaffina, Rita Carsetti, Anna Ruggieri and Paolo Garagnani
Vaccines 2024, 12(8), 880; https://doi.org/10.3390/vaccines12080880 - 2 Aug 2024
Cited by 2 | Viewed by 2416
Abstract
Healthcare workers (HCWs) are a high-risk group for hepatitis B virus (HBV) infection. Notably, about 5–10% of the general population does not respond to the HBV vaccination. In this study, we aimed to investigate DNA methylation (DNAm) in order to estimate the biological [...] Read more.
Healthcare workers (HCWs) are a high-risk group for hepatitis B virus (HBV) infection. Notably, about 5–10% of the general population does not respond to the HBV vaccination. In this study, we aimed to investigate DNA methylation (DNAm) in order to estimate the biological age of B cells from HCW of both sexes, either responder (R) or non-responder (NR), to HBV vaccination. We used genome-wide DNA methylation data to calculate a set of biomarkers in B cells collected from 41 Rs and 30 NRs between 22 and 62 years old. Unresponsiveness to HBV vaccination was associated with accelerated epigenetic aging (DNAmAge, AltumAge, DunedinPoAm) and was accompanied by epigenetic drift. Female non-responders had higher estimates of telomere length and lower CRP inflammation risk score when compared to responders. Overall, epigenetic differences between responders and non-responders were more evident in females than males. In this study we demonstrated that several methylation DNAm-based clocks and biomarkers are associated with an increased risk of non-response to HBV vaccination, particularly in females. Based on these results, we propose that accelerated epigenetic age could contribute to vaccine unresponsiveness. These insights may help improve the evaluation of the effectiveness of vaccination strategies, especially among HCWs and vulnerable patients. Full article
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15 pages, 285 KB  
Article
Comparison of the Psychological Impact of COVID-19 on Healthcare Workers between 2022 and 2023 in a Romanian COVID-19 Hub Hospital
by Monica Muntean, Doina Colcear, Violeta Briciu, Mihaela Lupse, Catalina Crisan, Maria Sidea and Amanda Radulescu
COVID 2024, 4(7), 1072-1086; https://doi.org/10.3390/covid4070074 - 14 Jul 2024
Cited by 1 | Viewed by 2025
Abstract
We assessed depression, anxiety, and stress in healthcare workers (HCWs) in 2023 and the evolution of depression in 2023 compared with 2022. In September–November 2023, 181 HCWs from the Infectious Diseases Hospital, Cluj-Napoca, Romania, completed the Depression, Anxiety, and Stress 21 Scale (DASS-21 [...] Read more.
We assessed depression, anxiety, and stress in healthcare workers (HCWs) in 2023 and the evolution of depression in 2023 compared with 2022. In September–November 2023, 181 HCWs from the Infectious Diseases Hospital, Cluj-Napoca, Romania, completed the Depression, Anxiety, and Stress 21 Scale (DASS-21 R), the Patient Health Questionnaire 9 (PHQ-9), and the Hamilton Anxiety Rating Scale (HAM-A). The prevalence of moderate-to-severe levels was 13.8% for DASS-Depression, 18.8% for DASS-Anxiety, 16.1% for DASS-Stress, 19.9% for PHQ-9, and 18.2% for HAM-A. Moderate-to-severe PHQ-9 depression was significantly lower in the 2023 study group (19.9%, N = 181) compared with 2022 (30.6%, N = 114) (p = 0.04), also within the 2022–2023 follow-up participants (N = 88) (p = 0.03). We did not find significant statistical differences between those infected vs. non-infected, vaccinated vs. non-vaccinated, or working with vs. not working with SARS-CoV-2 infected patients. Males were significantly more stressed (p = 0.02) and anxious (p = 0.03), and physicians in training had the highest prevalence of moderate-to-severe depression (31.6%), followed by physicians (25.6%). In 2023, depression, anxiety, and stress symptoms decreased but remained within a concerning range. By addressing these psychological issues, we may reduce the possibility of medical errors and prevent professional crises in the healthcare system. Full article
10 pages, 252 KB  
Article
Questionable Immunity to Mumps among Healthcare Workers in Italy—A Cross-Sectional Serological Study
by Cristiana Ferrari, Giuseppina Somma, Michele Treglia, Margherita Pallocci, Pierluigi Passalacqua, Luca Di Giampaolo and Luca Coppeta
Vaccines 2024, 12(5), 522; https://doi.org/10.3390/vaccines12050522 - 10 May 2024
Cited by 1 | Viewed by 3006
Abstract
Highly contagious diseases, such as mumps, are a global concern as new epidemics continue to emerge, even in highly vaccinated populations. The risk of transmission and spread of these viruses is even higher for individuals who are more likely to be exposed, including [...] Read more.
Highly contagious diseases, such as mumps, are a global concern as new epidemics continue to emerge, even in highly vaccinated populations. The risk of transmission and spread of these viruses is even higher for individuals who are more likely to be exposed, including healthcare workers (HCWs). In healthcare settings, both HCWs and patients are at risk of infection during the care process, potentially leading to nosocomial epidemic outbreaks. Mumps is often underestimated compared with measles and rubella, despite being milder and less likely to spread. In fact, the risk of complications following mumps infection is extremely high, especially if the disease occurs in adulthood. The measles–mumps–rubella (MMR) vaccine has been shown to be an excellent preventive measure. Unfortunately, the mumps component appears to be less effective in inducing immunity than those for measles and rubella (two-dose effectiveness of 85%, 95% and 97%, respectively). The main aim of our study was to investigate the prevalence of detectable mumps antibodies (serum IgG antibodies) in a cohort of Italian and foreign HCWs in relation to personal and occupational factors. We included in the study 468 subjects who underwent health surveillance at the Occupational Medicine Unit of the Tor Vergata Polyclinic in Rome during the period from January 2021 to March 2023. In our study, the proportion of HCWs found to be unprotected against mumps was very high (8.3%), and those found to be immune are below the WHO threshold for herd immunity (95%). From our data, it seems essential that all occupational health services carry out an accurate screening with a dose of anti-mumps antibodies to assess serological protection before starting a job, regardless of an individual’s vaccination history. This approach is proving to be beneficial, accurate, as it allows all serologically non-immune individuals to be vaccinated in the workplace, including those who would be protected by their vaccination history but have lost the antibody response. Full article
(This article belongs to the Special Issue Promoting Vaccination in the Post-COVID-19 Era)
11 pages, 1263 KB  
Article
The Effectiveness of the Third Dose of COVID-19 Vaccine: When Should It Be Performed?
by Giacomo Biganzoli, Marco Mendola, Pier Mario Perrone, Laura Maria Antonangeli, Anna Beatrice Elena Longo, Paolo Carrer, Claudio Colosio, Dario Consonni, Giuseppe Marano, Patrizia Boracchi, Elia Biganzoli and Silvana Castaldi
Vaccines 2024, 12(3), 315; https://doi.org/10.3390/vaccines12030315 - 16 Mar 2024
Cited by 5 | Viewed by 2870
Abstract
Background: COVID-19 vaccination is the most significant step toward the long-term mitigation of SARS-CoV-2-related complication, avoiding disease and death and decreasing virus spread. This study aimed to evaluate, in a real-world setting, booster dose effectiveness to reduce COVID-19 risk considering the amount of [...] Read more.
Background: COVID-19 vaccination is the most significant step toward the long-term mitigation of SARS-CoV-2-related complication, avoiding disease and death and decreasing virus spread. This study aimed to evaluate, in a real-world setting, booster dose effectiveness to reduce COVID-19 risk considering the amount of time after the end of the two-dose vaccination cycle. A sub-analysis was conducted to adjust the booster dose effect for occupational and demographic factors. Methods: About 16,000 COVID-19-vaccinated HCWs of three University Hospital Networks in Milan (HN1/HN2/HN3) were included in the study. Data were collected by Occupational Health Physicians of the HNs within specific computerized databases. Results: In univariable analysis, booster dose administration displayed a slightly higher risk of infection with respect to not receiving it, OR = 1.18, with 95% confidence interval (C.I) [0.99, 1.41]. When the model was adjusted with the modulating effect of time from the completion of the vaccination cycle on booster dose administration, the latter resulted in strong protective effect against infection, OR = 0.43, 95% CI [0.26, 0.74]. However, considering the modifying influence of time from the vaccination cycle’s completion, the administration of booster doses appeared to have a protective effect against infection. In HN1, students and resident physicians displayed lower odds of infection with respect to physicians. Lastly, a non-linear effect of age was reported. Conclusions: Our findings suggest that the correct timing in vaccine scheduling and administration is critical to vaccine effectiveness. These findings, applicable to all vaccinations, should help in setting up more effective vaccination strategies. Full article
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13 pages, 1639 KB  
Article
COVID-19 Antibody Levels among Various Vaccination Groups, One-Year Antibody Follow-Up in Two University Hospitals from Western and Central Turkey
by Mehmet Soylu, Pınar Sağıroğlu, Muhammed Alper Özarslan, Oğuzhan Acet, Zeynep Türe Yüce, Feyza İzci Çetinkaya, Seyfi Durmaz, Ömür Mustafa Parkan, Deniz Akyol, Ayşin Zeytinoğlu, Gamze Kalın Ünüvar, Meltem Taşbakan, Selma Gökahmetoğlu, Mustafa Altay Atalay, İsabel Raika Durusoy, Candan Çiçek, Hüsnü Pullukçu, Orhan Yıldız, Şaziye Rüçhan Sertöz and Memnune Selda Erensoy
Vaccines 2024, 12(1), 59; https://doi.org/10.3390/vaccines12010059 - 7 Jan 2024
Cited by 1 | Viewed by 2835
Abstract
Various clinical outcomes, reinfections, vaccination programs, and antibody responses resulted from the COVID-19 pandemic. This study investigated the time-dependent changes in SARS-CoV-2 antibody responses in infected and/or vaccinated and unvaccinated individuals and to provide insights into spike and nucleocapsid antibodies, which fluctuate during [...] Read more.
Various clinical outcomes, reinfections, vaccination programs, and antibody responses resulted from the COVID-19 pandemic. This study investigated the time-dependent changes in SARS-CoV-2 antibody responses in infected and/or vaccinated and unvaccinated individuals and to provide insights into spike and nucleocapsid antibodies, which fluctuate during infectious and non-infectious states. This cohort study was carried out at the Ege University Faculty of Medicine hospital in İzmir (western Turkey) and the Erciyes University Faculty of Medicine hospital in Kayseri (central Turkey) between December 2021 and January 2023, which coincided with the second half of COVID-19 pandemic. The study included 100 COVID-19 PCR-positive patients and 190 healthcare workers (HCWs). Antibody levels were followed up via quantitative anti-SARS-CoV-2 spike and qualitative anti-nucleocapsid immunoassays (Elecsys™). Antibody levels declined after infection but persisted for at least 6–8 months. Individuals who had received only CoronaVac had higher anti-nucleocapsid antibody levels in the early months than those who received mixed vaccination. However, anti-spike antibodies persisted longer and at higher levels in individuals who had received mixed vaccinations. This suggests that combining two different vaccine platforms may provide a synergistic effect, resulting in more durable and broad-spectrum immunity against SARS-CoV-2. The study provides information about the vaccination and antibody status of healthcare workers in the second half of the pandemic and provides valuable insights into the dynamics of antibody responses to COVID-19 infection and vaccination. Full article
(This article belongs to the Special Issue SARS-CoV-2: Vaccines in the Pandemic Era)
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15 pages, 279 KB  
Article
Factors Influencing the Healthcare Workers’ Willingness to Receive the COVID-19 Booster Dose in Tuscany (Italy)
by Giovanni Guarducci, Giovanna Mereu, Davide Golinelli, Giacomo Galletti, Fabrizio Gemmi, Alessandra Cartocci, Nora Holczer, Luca Bacci, Alessandro Sergi, Gabriele Messina, Valerio Mari and Nicola Nante
Vaccines 2023, 11(12), 1751; https://doi.org/10.3390/vaccines11121751 - 24 Nov 2023
Cited by 9 | Viewed by 2098
Abstract
Background: The World Health Organization has defined vaccine hesitancy as behavior influenced by several factors, including trust in the vaccine itself or its provider or the perceived need for vaccination. The aim of this study was to investigate the factors influencing the willingness [...] Read more.
Background: The World Health Organization has defined vaccine hesitancy as behavior influenced by several factors, including trust in the vaccine itself or its provider or the perceived need for vaccination. The aim of this study was to investigate the factors influencing the willingness to receive the COVID-19 vaccine among the employees and healthcare professionals of the Central Tuscany Local Health Authority (CT-LHA) in Italy. Methods: From July to October 2022, a cross-sectional study was conducted. An online questionnaire was administered to 7000 employees of the CT-LHA. The questionnaire analyzed the factors that influenced receiving the booster dose of the COVID-19 vaccine. The sample was stratified by gender, age, type of occupation (healthcare or non-healthcare workers), and seniority. Incomplete questionnaires were excluded. A chi-squared test was performed through STATA. The significance level was set at 95%. Results: Of the questionnaires administered, 1885 (26.9%) questionnaires were eligible for the study. In the previous vaccination campaign, the healthcare workers (HCWs) considered the vaccine used by CT-LHA as safe, in contrast to non-healthcare workers (N-HCWs), who considered it less secure (p < 0.05). The HCWs showed a higher propensity for vaccine safety to receive the booster dose than N-HCWs. N-HCWs appeared to be less affected by an updated booster dose than HCWs (p < 0.05). Conclusions: The factors studied appear to influence HCWs differently from N-HCWs. Both HCWs and N-HCWs would choose an upgraded mRNA vaccine for the booster dose. Full article
11 pages, 516 KB  
Article
SARS-CoV-2 Infections, Re-Infections and Clinical Characteristics: A Two-Year Retrospective Study in a Large University Hospital Cohort of Vaccinated Healthcare Workers
by Luigi De Maria, Giuseppe Delvecchio, Stefania Sponselli, Francesco Cafaro, Antonio Caputi, Gianmarco Giannelli, Pasquale Stefanizzi, Francesco Paolo Bianchi, Angela Stufano, Silvio Tafuri, Piero Lovreglio, Paolo Boffetta and Luigi Vimercati
J. Clin. Med. 2023, 12(21), 6800; https://doi.org/10.3390/jcm12216800 - 27 Oct 2023
Cited by 6 | Viewed by 2580
Abstract
At the University Hospital of Bari, during the first year after the start of the mandatory vaccination campaign with BNT162b2 mRNA COVID-19 vaccine, the preliminary results of an observational study showed a significant prevalence of SARS-CoV-2 breakthrough infections (BIs) among healthcare workers (HCWs), [...] Read more.
At the University Hospital of Bari, during the first year after the start of the mandatory vaccination campaign with BNT162b2 mRNA COVID-19 vaccine, the preliminary results of an observational study showed a significant prevalence of SARS-CoV-2 breakthrough infections (BIs) among healthcare workers (HCWs), but no hospitalization or deaths. In the present study, we extended the observation period (January 2021–January 2023) with the aim of determining the incidence, characteristics and clinical course of SARS-CoV-2 BIs among 6213 HCWs. All HCWs were regularly monitored and screened. To allow return to work after BI, the protocol required one negative nasopharyngeal swab test followed by a medical examination certifying complete clinical recovery. We observed an overall incidence rate of SARS-CoV-2 BIs of 20.2%. Females were most affected, especially in the nurse group compared with doctors and other HCWs (p < 0.0001). Cardiovascular diseases were the most frequent comorbidity (n = 140; 11.4%). The source of infection was non-occupational in 52.4% of cases. Most cases (96.9%) showed minor symptoms and only two cases of hospitalization (one in intensive care unit), 13 cases of re-infection and no deaths were recorded. Our results confirm that SARS-CoV-2 infection can break vaccination protection but the clinical course is favorable. Full article
(This article belongs to the Special Issue Epidemiology and Clinical Characteristics of COVID-19)
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16 pages, 287 KB  
Article
Determinants of COVID-19 Vaccine Acceptability among Healthcare Workers in Kenya—A Mixed Methods Analysis
by Victor Mudhune, Ken Ondeng’e, Fanuel Otieno, Derick B. Otieno, Collins M. Bulinda, Ikechukwu Okpe, Sarah Nabia, Naor Bar-Zeev, Omondi Otieno and Chizoba Wonodi
Vaccines 2023, 11(8), 1290; https://doi.org/10.3390/vaccines11081290 - 27 Jul 2023
Cited by 8 | Viewed by 2544
Abstract
Healthcare workers (HCWs) were a priority group for COVID-19 vaccination. Adopting the World Health Organization’s 3C and the expanded 5C vaccine hesitancy models, we assessed the factors associated with COVID-19 vaccine acceptability among HCWs in Kenya. In a mixed methods study, respondents were [...] Read more.
Healthcare workers (HCWs) were a priority group for COVID-19 vaccination. Adopting the World Health Organization’s 3C and the expanded 5C vaccine hesitancy models, we assessed the factors associated with COVID-19 vaccine acceptability among HCWs in Kenya. In a mixed methods study, respondents were from eight selected counties across the country. An online survey (n = 746), key informant interviews (n = 18) and focus group discussions (n = 3) were conducted. The data were analyzed concurrently. Quantitative data showed that all the 3C antecedents were strong predictors of vaccine acceptability. The association of vaccine acceptability was strongest with convenience (aOR 20.13, 95% CI 9.01–44.96), then complacency (aOR 10.15, 95% CI 4.63–22.21) and confidence (aOR 6.37, 95% CI 2.90–14.02). Marital status was a significant independent factor associated with vaccine acceptability (aOR 2.70, 95% CI 1.20–6.08). Qualitatively, convenience presented as the no-cost availability of vaccines at the health facilities, whereas non-complacency manifested from the first-hand observed experience of COVID cases, and the need to protect oneself and family members. Confidence was mainly attributed to increased knowledge, resulting from multiple training sessions and trust in regulatory authorities. Other social factors including workplace pressure, religion and misinformation had a role in influencing HCW vaccination decisions. In the background of a pandemic, the 3C model is a strong predictor of vaccine acceptability, and making the vaccines easily available and convenient to HCWs significantly impacts their uptake. Full article
(This article belongs to the Special Issue Vaccination Uptake and Public Health)
12 pages, 276 KB  
Article
Respiratory Syncytial Virus (RSV) Disease and Prevention Products: Knowledge, Attitudes, and Preferences of Kenyan Healthcare Workers in Two Counties in 2021
by Bryan O. Nyawanda, Victor A. Opere, Joyce U. Nyiro, Elisabeth Vodicka, Jessica A. Fleming, Ranju Baral, Sadaf Khan, Clint Pecenka, Jorim O. Ayugi, Raphael Atito, James Ougo, Godfrey Bigogo, Gideon O. Emukule, Nancy A. Otieno and Patrick K. Munywoki
Vaccines 2023, 11(6), 1055; https://doi.org/10.3390/vaccines11061055 - 2 Jun 2023
Cited by 8 | Viewed by 2819
Abstract
Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infection (LRTI) among infants under 6 months of age. Yet, in Kenya, little is known about healthcare workers’ (HCWs) knowledge, attitudes, and perceptions around RSV disease and the prevention products under [...] Read more.
Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infection (LRTI) among infants under 6 months of age. Yet, in Kenya, little is known about healthcare workers’ (HCWs) knowledge, attitudes, and perceptions around RSV disease and the prevention products under development. Between September and October 2021, we conducted a mixed methods cross-sectional survey to assess HCWs’ knowledge, attitudes, and perceptions of RSV disease and RSV vaccinations in two counties. We enrolled HCWs delivering services directly at maternal and child health (MCH) departments in selected health facilities (frontline HCWs) and health management officers (HMOs). Of the 106 respondents, 94 (88.7%) were frontline HCWs, while 12 were HMOs. Two of the HMOs were members of the Kenya National Immunization Technical Advisory Group (KENITAG). Of the 104 non-KENITAG HCWs, only 41 (39.4%) had heard about RSV disease, and 38/41 (92.7%) felt that pregnant women should be vaccinated against RSV. Most participants would recommend a single-dose vaccine schedule (n = 62, 58.5%) for maximal adherence and compliance (n = 38/62, 61.3%), single dose/device vaccines (n = 50/86, 58.1%) to prevent wastage and contamination, and maternal vaccination through antenatal care clinics (n = 53, 50%). We found the need for increased knowledge about RSV disease and prevention among Kenyan HCWs. Full article
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