Active Surveillance of Adverse Events in Healthcare Workers Recipients After Vaccination with COVID-19 BNT162b2 Vaccine (Pfizer-BioNTech, Comirnaty): A Cross-Sectional Study

Increasing vaccination coverage among healthcare workers: Active call and mandatory laws. Data from a large general hospital in Southern Italy

Influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are respiratory pathogens which significantly impact healthcare systems. Seasonal vaccination is recommended for all healthcare workers (HCWs) to reduce the risk for both operators and patients. Puglia, a region in Southern Italy, has been enforcing since 2018 a law mandating influenza vaccination in healthcare workers. However, vaccination coverages for this category have always been suboptimal. Our study tests the effectiveness of an active recall intervention on vaccination coverage for influenza and SARS-CoV-2 in the HCWs of a large Apulian hospital (Southern Italy). During the 2023-2024 influenza vaccination season, unvaccinated HCWs of Bari's Policlinico General Hospital were contacted. The e-mail reminded them of a regional law mandating influenza vaccination to all HCWs and offered an appointment for vaccination. SARS-CoV-2 vaccination was also offered. In 2022-2023, 43.16 % of HCWs were vaccinated against influenza and 21.87 % against SARS-CoV-2. Coverage changed during the 2023-2024 season to 54.11 % and 13.58 %, respectively. A regression model showed that vaccination uptake's increase was associated with the e-mail reception and with the operator being a physician vs. non-medical personnel. On the contrary, subjects who received the e-mail did not show an increased SARS-CoV-2 vaccination uptake, which was on the contrary influenced by the worker's age, sex, job title, and area of risk. Our soft-mandate intervention was effective in increasing vaccination uptake by HCWs. Communication with a trained specialist was probably useful, and the possibility to access vaccination services with dedicated appointments increased convenience. Mandatory vaccination policies and active recall seem to synergically impact vaccination uptake.

Psychiatric adverse events associated with the COVID-19 vaccines approved in the Republic of Korea: a systematic review

This systematic review evaluated psychiatric adverse events (AEs) following vaccination against coronavirus disease 2019 (COVID-19). We included studies that reported or investigated psychiatric AEs in individuals who had received an approved COVID-19 vaccine in the Republic of Korea. Systematic electronic searches of Ovid-Medline, Embase, CENTRAL, and KoreaMed databases were conducted on March 22, 2023. Risk of bias was assessed using the Risk of Bias Assessment Tool for Non-randomized Studies 2.0. The study protocol was registered in the International Prospective Register of Systematic Reviews (CRD42023449422). Of the 301 articles initially selected, 7 were included in the final analysis. All studies reported on sleep disturbances, and 2 highlighted anxiety-related AEs. Sleep disorders like insomnia and narcolepsy were the most prevalent AEs, while depression was not reported. Our review suggests that these AEs may have been influenced by biological mechanisms as well as the broader psychosocial context of the COVID-19 pandemic. Although this study had limitations, such as a primary focus on the BNT162b2 vaccine and an observational study design, it offered a systematic, multi-vaccine analysis that fills a critical gap in the existing literature. This review underscores the need for continued surveillance of psychiatric AEs and guides future research to investigate underlying mechanisms, identify risk factors, and inform clinical management.

Sex differences in the relationship between post-vaccination adverse reactions, decision regret, and WTP for the booster dose of COVID-19 vaccine in Taizhou, China

This study investigated sex differences in the relationship between post-vaccination adverse reactions, decision regret, and willingness to pay (WTP) for the booster dose of COVID-19 vaccines. This research carried out an online cross-sectional investigation among healthcare workers (HCWs) in Taizhou, China. In total, 1,054 respondents (165 males and 889 females) have received two-dose COVID-19 vaccination. We performed descriptive analysis, chi-square test, and mediation analysis on the exported data. In this study, 67 (40.6%) males and 429 (48.3%) females had WTP for the booster dose. Our study presented that decision regret mediated the effect of adverse reactions after vaccination on WTP for the booster dose in both male and female groups. In males, decision regret played a completely mediating role, while in females, it acted as a partial mediator. Sex differences in the relationship between post-vaccination side effects, decision regret, and WTP for the third dose were demonstrated in a sample of healthcare workers.

Safety of mRNA BNT162b2 COVID-19 (Pfizer-BioNtech) vaccine in children aged 5-11 years: Author's reply to correspondence

Dear Editor, We would like to reply to "Safety of mRNA BNT162b2 COVID-19 (Pfizer-BioNtech) vaccine in children aged 5-11years: Correspondence" regarding our article entitled "Safety of mRNA BNT162b2 COVID-19 (Pfizer-BioNTech) vaccine in children aged 5-11years: Results from an active pharmacovigilance study in central Italy."

Association Between Pfizer COVID-19 Vaccine Adverse Effects and Diabetes Mellitus: A Prospective Multicenter Study

Introduction The epidemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) triggered the contagion of coronavirus disease 2019 (COVID-19), which killed many individuals globally. The Pfizer BioNTech vaccine was the first messenger ribonucleic acid (mRNA)-based vaccine that boosted immunity against various adverse reactions. The objective of this study was to evaluate the frequency of Pfizer vaccine side effects among participants with and without diabetes mellitus (DM). Methods This multicenter study was cross-sectional and was performed using a non-probability consecutive sampling technique. The study duration was six months, from October 1, 2022, to March 31, 2023. A total of 750 participants who received both doses of the Pfizer vaccine were included in the study. Demographic details such as gender, age, comorbidities, preceding COVID-19 infection, and the occurrence of any local and systemic side effects of the first and second doses of vaccine were recorded. The association between local and general side effects and the presence of DM was assessed using the chi-square test. Results Of the 750 participants included in the study, 289 (77.1%) were males with diabetes mellitus (DM), and 217 (57.9%) were non-diabetic participants; however, 86 (22.9%) females had DM, and 158 (42.1%) were non-diabetic; their mean ages were 48.23 ± 16.22 and 37.56 ± 12.15 years, respectively. The most commonly occurring side effects after receiving the first dose of the Pfizer vaccine were: injection site burning in 251 (66.9%) diabetic and 254 (67.7%) non-diabetic participants. Likewise, the frequency of side effects of the second dose of the Pfizer vaccine showed that the most commonly reported side effects were: muscle pain, found in 240 (64.0%) diabetic patients and 194 (51.7%) non-diabetics, with a statistically significant association (p =0.001). Conclusion This study concluded that participants with DM had local and general adverse effects considerably more frequently than those without DM. The most frequently observed adverse effects in both diabetic and non-diabetic participants were injection site burning, rashes, muscle pain, and fever after receiving both doses of the Pfizer vaccine. Moreover, most of the side effects were minor.

Comprehensive evaluation of the effect of inactivated SARS-CoV-2 vaccination on female fertility: A retrospective cohort study

Fear of possible negative effects of coronavirus disease 2019 (COVID-19) vaccine on fertility is the main reason for vaccine hesitancy among the public especially women of childbearing age. Despite the high coverage of COVID-19 vaccination in China, more scientific evidence is still needed to address their concerns and guide fertility counseling and management in the future. Herein, we performed a retrospective cohort study at a single large center for reproductive medicine in China between August 2020 and May 2023. Patients aged 20-42 years with no history of laboratory-confirmed COVID-19 were included and categorized into different groups according to their vaccination status. The serum sex hormone levels, anti-Müllerian hormone concentrations, embryo quality, and pregnancy outcomes were evaluated and compared among them. We found there were no significant differences in the concentrations of follicle-stimulating hormone, luteinizing hormone and progesterone between the unvaccinated, first-dose, second-dose, and booster vaccinated groups. However, the estradiol showed a highly significant increase in the one-dose vaccinated group compared with its levels in other groups. Among unvaccinated and either vaccinated patients, anti-Müllerian hormone levels were comparable (p = 0.139). The number of oocytes retrieved, fertilization rate and good-quality embryo rate were all similar between each group of in vitro fertilization and intracytoplasmic sperm injection. No significant differences were observed regarding other laboratory parameters. Moreover, the vaccination status of infertile couples did not exert any adverse effect on the pregnancy outcomes in all assisted reproductive technologies cycles. In short, we comprehensively evaluated the reproductive safety of inactivated severe acute respiratory syndrome coronavirus 2 vaccine and found any dose of vaccination wouldn't negatively affect female fertility parameters such as sex hormone levels and ovarian reserve. Moreover, this is the first study to complete the live birth follow-up of the cohort after receiving inactivated severe acute respiratory syndrome coronavirus 2 vaccine, further dispelling the misconception and providing reassurance for decision-making by clinicians.

Protective Anti-HBs Antibodies and Response to a Booster Dose in Medical Students Vaccinated at Childhood

The immune system in humans is regulated by the circadian rhythm. Published studies have reported that the time of vaccination is associated with the immune response to vaccine for some pathogens. Our study aimed to evaluate the association between time of dose administration of challenge HBV vaccine and seroconversion for anti-HBs in medical students vaccinated at birth who were found to be unprotected at pre-training screening. Humoral protection for HBV was assessed in 885 medical students vaccinated during childhood. In total, 359 (41.0%) of them showed anti-HBs titer < 10 UI/mL and received a challenge dose of HBV vaccine followed by post-vaccination screening 30-60 days later. The challenge dose elicited a protective immune response (anti-HBs IgG titer > 10 UI/mL) in 295 (83.8%) individuals. Seroconversion was significantly associated with female gender and time of vaccination after controlling for age group and nationality at logistic regression analysis. Students who received the booster dose in the morning had a higher response rate than those who received the vaccine in the afternoon (OR 1.93; 95% C.I. 1.047-3.56: p < 0.05). This finding suggests that morning administration of the HBV booster may result in a better immune response in susceptible individuals.

Emerging Progress of RNA-Based Antitumor Therapeutics

RNA-based therapeutics (e.g., mRNAs, siRNAs, microRNAs, ASOs, and saRNAs) have considerable potential for tumor treatment. The development and optimization of RNA modifications and delivery systems enable the stable and efficient delivery of RNA cargos in vivo to elicit an antitumor response. Targeted RNA-based therapeutics with multiple specificities and high efficacies are now available. In this review, we discuss progress in RNA-based antitumor therapeutics, including mRNAs, siRNAs, miRNAs, ASOs, saRNAs, RNA aptamers, and CRISPR-based gene editing. We focus on the immunogenicity, stability, translation efficiency, and delivery of RNA drugs, and summarize their optimization and the development of delivery systems. In addition, we describe the mechanisms by which RNA-based therapeutics induce antitumor responses. Furthermore, we review the merits and limitations of RNA cargos and their therapeutic potential for cancers.

Common Side Effects of Pfizer COVID-19 Vaccine: An Experience From Pakistan

Introduction The severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) epidemic spread quickly. Vaccines are now being distributed to stop the infectious spread and halt fatalities. The Pfizer-BioNTech vaccine was the first mRNA-based vaccine introduced to boost immunity against COVID-19; however, it could lead to various adverse reactions. Therefore, the aim of this study was to assess the prevalence of Pfizer vaccine side effects among participants. Methods This was a multicenter cross-sectional study that was performed using a non-probability sampling method. The study period was about six months from March 1, 2022, to August 31, 2022. A total of 1000 participants who received two doses of the Pfizer vaccine met the inclusion criteria. Demographic details of participants, for example, gender, age, comorbidities, Pfizer vaccine with both doses along with booster dose, previous exposure to coronavirus disease 2019 (COVID-19) infection, and the incidence of any local and systemic side effects following the first and second doses of vaccine, were reported.  Results The study findings showed that out of 1000 participants, 644 (64.4%) were males and 356 (35.6%) were females; their mean age was 43.06±14.98 years. Among them, 280 (28.0%) had hypertension and 356 (35.6%) had diabetes. Following the first dose of the Pfizer vaccine, burning at the injection site and fever were the most commonly reported side effects in 704 (70.4%) and 700 (70.0%) participants, respectively. Following the second dose of the Pfizer vaccine, muscle pain was the most commonly reported side effect in 628 (62.8%) participants. Conclusion This study concluded that the most frequent adverse effects of the Pfizer vaccine were burning at the injection site, fever, pain at the injection site, muscle pain, swelling at the injection site, and joint pain. Moreover, the first dose was associated with more side effects than the second dose.

Adverse Events to Comirnaty Vaccine Are Linked to Sex, Age and BMI: Should We Consider Reducing the Dose for Females?

An important issue that is often neglected is the difference between male and female genders in response to medical treatments. In the context of COVID-19 vaccine administration, despite identical protocol strategies, it has been observed that females often suffer more adverse consequences than males. Here, we analyzed the adverse events (AEs) of the Comirnaty vaccine in a population of 2385 healthcare workers as a function of age, sex, COVID-19 history and BMI. Using logistic regression analysis, we showed that these variables may contribute to the development of AEs, particularly in young subjects, females and individuals with a BMI below 25 kg/m2. Moreover, partial dependence plots indicate a 50% probability of developing a mild AE for a long period of time (≥7 days) or a severe AE of any duration in women below 40 years old and with a BMI < 20 kg/m2. As this effect is more evident after the second dose of the vaccine, we propose to reduce the amount of vaccine for any additional booster dose in relation to age, sex and BMI. This strategy might reduce adverse events without affecting vaccine efficacy.

BNT162b2 COVID-19 Vaccine Safety among Healthcare Workers of a Tertiary Hospital in Italy

Millions of people have died because of the COVID-19 pandemic. The vaccination campaign helped tackle the pandemic and saved millions of lives. In a retrospective pharmacovigilance study, we explored the safety of the BNT162b2 (Comirnaty) vaccine among healthcare workers (HCWs) in a large Italian teaching hospital, and 2428 Adverse Events Reports (AERs) filed by HCWs after the administration of the first dose of vaccine were collected and analyzed, reporting the results quantitively and comparing them to the vaccine Summary of Product Characteristics (SPC). Spearman's correlation coefficients were computed to investigate the correlation among reported adverse effects, and recurrent clusters of symptoms were investigated through the Principal Component Analysis (PCA) and k-means Cluster Analysis. The BNT162b2 vaccine's safety profile was favorable, with predominant reports of early onset, mild, non-serious and short-term resolved symptoms. We observed higher than the expected frequency for various non-serious undesirable effects, especially among those listed and classified as less common in the SPC. Furthermore, we identified three clusters of adverse effects that were frequently reported together, defined by the presence/absence of fatigue, malaise, localized pain, chills, pyrexia, insomnia, nausea and injection site pain. Post-marketing pharmacovigilance activities, together with targeted public health interventions, can be valuable tools to promote vaccination and improve the control of the spread of the pandemic, especially in sensitive settings and populations such as hospitals and healthcare professionals.

Effectiveness of the BBV-152 and AZD1222 vaccines among adult patients hospitalized in tertiary hospitals in Odisha with symptomatic respiratory diseases: A test-negative case-control study

Two vaccines, namely BBV-152 (COVAXIN^®) and AZD1222 (COVISHIELD™), were deployed against SARS-CoV-2 in India from January 16, 2021. Frontline health care workers were vaccinated first, followed by the adult population. However, limited data on vaccine effectiveness are available for the population of India. Therefore, we aimed to evaluate the effectiveness of two doses of each of these two common vaccines against COVID-19 infection among hospitalized patients with pulmonary conditions. We adopted a test-negative case-control design and recruited a sample of adults who were admitted to one of six tertiary care hospitals in Odisha. All participants were hospitalized patients with COVID-19-like pulmonary signs and symptoms. Participants who tested positive for SARS CoV-2 via RT-PCR were treated as cases, and those who tested negative were treated as controls. Logistic regression, adjusted for participants' age, sex, and number of comorbidities, was used to calculate the effectiveness of the two vaccines, using the formula: 100^*(1 - adjusted odds ratio). Between March and July of 2021, data were collected from 1,614 eligible adults (864 cases and 750 controls). Among all participants, 9.7% had received two doses of one of the two COVID-19 vaccines. Vaccine effectiveness was 74.0% (50.5%-86.0%) for two doses of BBV-152 and 79.0% (65.4%-87.2%) for two doses of AZD1222. Thus, two doses of either BBV-152 or AZD1222 nCoV-19 vaccine were found to be substantially effective in protecting against COVID-19-related infection.

Side effects of Pfizer/BioNTech (BNT162b2) COVID-19 vaccine reported by the Birzeit University community

BACKGROUND

The Pfizer BioNTech COVID-19 vaccine was the first to receive emergency authorization and approval from the FDA. Therefore, it is preferred by most recipients; however, many people are concerned about the vaccine's side effects. At the time of the study, December 2021, Palestine lacked a national reporting system for monitoring adverse vaccine effects. Therefore, this study investigates the post-vaccine adverse events following the Pfizer/BioNTech COVID-19 Vaccine administration in Palestine and identifies the occurrence, extent, and severity among university staff, employees, and students at Birzeit University.

METHOD

A questionnaire-based retrospective cross-sectional study was conducted using a university website (Ritaj), social media platforms (e.g., Facebook and Telegram), and in-person interviews. The Chi-square, Fisher's exact, and McNemar's tests were used to investigate significant relationships. Data were analyzed using SPSS version 22.

RESULTS

In total, 1137 participants completed the questionnaire, 33.2% were males, and the mean age was 21.163 years. All participants received at least one dose of the Pfizer-BioNTech COVID-19 vaccine. Approximately one-third of participants reported no adverse effects after receiving the first, second, or third doses (34%, 33.6%, and 32.5%, respectively). The most commonly reported adverse events were fever, chills, headache, fatigue, pain and swelling at the injection site, muscle pain, and joint pain. Allergic reactions were reported by 12.7% of the participants; furthermore, participants with a history of allergy or anaphylaxis before vaccination had a significantly higher tendency for post-vaccination allergic reactions. Eight participants reported rare side effects, including 7 (0.6%) cases of thrombocytopenia and one (0.1%) case of myocarditis. Males aged less than 20 years and smokers were significantly less likely to complain of adverse events. The number of reported side effects was significantly higher after the second vaccine dose than after the first dose. Finally, participants infected with COVID-19 before vaccination was significantly associated with side effects such as fever, chills, shortness of breath, and persistent cough.

CONCLUSION

In this study, the most common post- BNT162b2 Vaccination reported self-limiting side effects similar to those reported by Pfizer/BioNTech Company. However, higher rates of allergic reactions were reported in this sample. Rare side effects, such as thrombocytopenia and myocarditis, were reported by 8 participants. COVID vaccines have been developed at an accelerated pace, and vaccine safety is a top priority; therefore, standard monitoring through a national adverse event reporting system is necessary for safety assurance. Continuous monitoring and long-term studies are required to ensure vaccine safety.

Sex-disaggregated outcomes of adverse events after COVID-19 vaccination: A Dutch cohort study and review of the literature

Background

Albeit the need for sex-disaggregated results of adverse events after immunization (AEFIs) is gaining attention since the COVID-19 pandemic, studies with emphasis on sexual dimorphism in response to COVID-19 vaccination are relatively scarce. This prospective cohort study aimed to assess differences in the incidence and course of reported AEFIs after COVID-19 vaccination between males and females in the Netherlands and provides a summary of sex-disaggregated outcomes in published literature.

Methods

Patient reported outcomes of AEFIs over a six month period following the first vaccination with BioNTech-Pfizer, AstraZeneca, Moderna or the Johnson&Johnson vaccine were collected in a Cohort Event Monitoring study. Logistic regression was used to assess differences in incidence of 'any AEFI', local reactions and the top ten most reported AEFIs between the sexes. Effects of age, vaccine brand, comorbidities, prior COVID-19 infection and the use of antipyretic drugs were analyzed as well. Also, time-to-onset, time-to-recovery and perceived burden of AEFIs was compared between the sexes. Third, a literature review was done to retrieve sex-disaggregated outcomes of COVID-19 vaccination.

Results

The cohort included 27,540 vaccinees (38.5% males). Females showed around two-fold higher odds of having any AEFI as compared to males with most pronounced differences after the first dose and for nausea and injection site inflammation. Age was inversely associated with AEFI incidence, whereas a prior COVID-19 infection, the use of antipyretic drugs and several comorbidities were positively associated. The perceived burden of AEFIs and time-to-recovery were slightly higher in females.

Discussion

The results of this large cohort study correspond to existing evidence and contribute to the knowledge gain necessary to disentangle the magnitude of the effect sex in response to vaccination. Whilst females have a significant higher probability of experiencing an AEFI than males, we observed that the course and burden is only to a minor extent different between the sexes.

From trial to practice: incidence and severity of COVID-19 vaccine side effects in a medically at-risk and vaccine-hesitant community

Background

The rapid authorization and widespread rollout of COVID-19 vaccines in the United States demonstrated a need for additional data on vaccine side effects, both to provide insight into the range and severity of side effects that might be expected in medically-diverse populations as well as to inform decision-making and combat vaccine hesitancy going forward. Here we report the results of a survey of 4825 individuals from southcentral Kentucky who received two doses of either the Pfizer-BioNTech (BNT162b2) or Moderna (mRNA-1273) vaccine between December 14, 2020 and May 1, 2021. As new versions of the vaccine are rolled-out, local initiatives such as this may offer a means to combat vaccine hesitancy in reference to COVID-19, but are also important as we face new viral threats that will necessitate a rapid vaccine rollout, and to combat a growing public distrust of vaccines in general.

Methods

Individuals that received two doses of either BNT162b2 or mRNA-1273 between December 14, 2020 and May 1, 2021 were sent a survey, created by the research team. Respondents were asked to rate the incidence and severity of 15 potential side effects and two related outcomes following each of their two doses of the vaccine. All statistical analyses were carried out using SYSTAT, version 13. The data were analyzed utilizing a range of statistical tests, including chi-square tests of association, Cohen’s h, Kruskal-Wallis test one-way nonparametric ANOVA, least-squares regression, and Wilcoxon signed-ranks test. Significance was assessed using Bonferroni-adjusted criteria within families of tests.

Results

In general, the pattern and severity in side effects was similar to both clinical trial data as well as other published studies. Responses to the mRNA-1273 vaccine were more severe than to BNT162b2, though all were generally in the mild to moderate category. Individuals who reported having previously tested positive for COVID-19 reported stronger responses following the first dose of either vaccine relative to COVID-naïve individuals. The reported severity to the COVID-19 vaccine was positively correlated with self-reported responses to other vaccines.

Conclusions

Our findings allow broad-scale estimates of the nature and severity of reactions one might expect following vaccination within a clinically-diverse community, and provide a context for addressing vaccine hesitancy in communities such as ours, where locally-generated data and communication may be more influential than national trends and statistics in convincing individuals to become vaccinated. Further, we argue this community-based approach could be important in the future in three key ways: 1) as new boosters and modified vaccines re-volatilize vaccine hesitancy, 2) as new vaccines receive similar testing and rapid authorization, and 3) to combat vaccine hesitancy in other arenas (e.g., annual vaccines, childhood vaccines).

Safety of mRNA BNT162b2 COVID-19 (Pfizer-BioNtech) vaccine in children aged 5-11 years: Results from an active pharmacovigilance study in central Italy

This survey investigated on adverse events after vaccination with mRNA BNT162b2 (Comirnaty, Pfizer-BioNTech) vaccine in children aged 5-11 years in central Italy through active surveillance reporting. During December 2021-January 2022, parents of children who undergone vaccination were interviewed using a structured questionnaire. 197 out of 208 contacted parents participated (94.7% response rate), of whom 166 (84.3%) had one child. Of the 229 children, the mean age was 8.9 years, 50.7% were female. 193 (84.3%) had at least one adverse event after the first dose (mean age 9.1 years; 54.4% female), and 146 (73.4%) of 199 after the second (mean age 8.9 years; 54.8% female), which was not administered to 30 children due to previous COVID-19 history. Local symptoms after the first and second dose occurred in 183 (94.8%) and 141 (96.6%) recipients (p = .435), respectively, while systemic reactions in 62 (32.1%) and 34 (23.3%) (p = .074). Mild events were reported by 81.7% and 69.8% children after the first and second dose, followed by moderate (3.9% and 10.6%) and severe (1.3% and 0.5%). After each dose, injection site reactions (79.5% and 68.8%) were the most frequent, followed by headache (13.1%) and lymphadenopathy (8.5%) after the first and second dose, respectively. The adverse events were reported to pediatricians only for 5.7% and 3.9% of children and treated for 17.6% and 15.8%. This is the first report about safety profile through active surveillance of mRNA BNT162b2 among children in Italy, revealing temporary and mild-to-moderate symptoms with no serious events after each vaccine dose.

COVID-19 Vaccination Trends and Side Effects among Egyptian Hemodialysis Patients: A Multicenter Survey Study

(1) Background: Vaccination may be a key intervention to prevent infection in chronic hemodialysis (CHD) patients. This study aimed to determine the COVID-19 vaccination status in Egyptian CHD patients and to analyze the safety and detailed side effect profile of the COVID-19 vaccine among these patients. (2) Methods: This survey-based study was conducted on 670 end-stage renal disease (ESRD) patients on CHD from 3 December 2021 to 5 February 2022. Subjects were asked about sociodemographic characteristics, clinical and therapeutic data, in addition to their COVID-19 vaccination status. If the subject had been vaccinated, we inquired about the type of vaccine and the side effects that occurred within a few days after administration of the first and second dose of the COVID-19 vaccine. Additionally, subjects were asked about the onset of side effects (days from vaccination), timing of maximum symptoms, intensity of symptoms and their effect on activity and need for medical attention. (3) Results: The study included 670 CHD patients with a mean age of 50.79 years; 58.1% were females. The vast majority (614; 91.6%) of the studied patients received two doses of the vaccine. Side effects were more commonly reported after the first dose than the second dose. The main side effects reported were generalized weakness/fatigue (56%), headache (43.8%) and fever (40.4%), and sore arm/pain was also reported (29.3%). Adverse events mostly occurred within one day after vaccination and the maximum symptoms usually happened on the second day. The median duration of symptoms was 3 days with a maximum duration up to 5 days. The univariate logistic regression analysis showed that male gender (OR 1.848; (95% CI, 1.242−2.749), p = 0.002), age (OR 0.981; (95% CI, 0.969−0.993), p = 0.003), smoking (OR 6.067; (95% CI, 3.514−10.475), p < 0.001), duration since starting HD (OR 0.998; (95% CI, 0.998−0.999), p < 0.001), associated comorbidities (OR 2.202; (95% CI, 1.478−3.281), p < 0.001) and prior COVID-19 infection (OR 3.318; (95% CI, 1.952−5.642), p < 0.001) were the main determinants of adverse events related to COVID-19 vaccination. (4) Conclusions: our preliminary findings support the favorable short-term safety profile of the COVID-19 vaccine among CHD patients, and hence can reassure both clinicians and patients, as well as further promote COVID-19 vaccine administration among these patients.

Common adverse events following immunization with the COVID-19 comirnaty vaccine (Pfizer-BioNTech) among adult population in Hanoi, Vietnam, 2021

Rationale

To prevent and control the COVID-19 pandemic, the biggest immunization campaign in history had been deployed worldwide. Therefore, it is important to inform the adverse events following immunization (AEFI) to populations.

Objectives

To prevent vaccine hesitancy, this study focused on finding the common AEFI with the COVID-19 Comirnaty vaccine (Pfizer-BioNTech) among participants aged 18 and above and related factors in Hanoi, Vietnam.

Methods

A cross-sectional study was carried out to collect participants’ data and AEFI after being vaccinated at Hanoi Medical University, Vietnam, in 2021. Logistic regression was utilized for analyzing the correlated factors of AEFI.

Results

We recruited a random sample of 820 participants who received both basic doses of Pfizer vaccine in September and October 2021. The proportion of AEFI after the first dose, second dose, and both doses of Pfizer vaccine was 24.4%, 64.2%, and 18.5%, respectively. AEFI mostly appeared within 1 day and lasted for 1 to 2 days. The AEFI were more common in females (OR=1.7; 95%CI=1.25–2.29) and younger age groups (OR=1.9; 95%CI=1.37–2.58). History of allergy, allergic diseases, chronic diseases, and occupations were not statistically significant with AEFI.

Conclusion

Our findings indicated that the COVID-19 Comirnaty vaccine is safe to be injected. Gender and age group are important factors influencing AEFI.

Longitudinal dynamics of SARS-CoV-2 anti-receptor binding domain IgG antibodies in a wide population of health care workers after BNT162b2 vaccination

OBJECTIVES

With the availability of vaccines, commercial assays detecting anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies evolved toward quantitative assays directed to the spike glycoprotein or its receptor-binding domain (RBD). The objective was to perform a large-scale, longitudinal study involving health care workers (HCWs), with the aim of establishing the kinetics of immune response throughout the 9-month period after receipt of the second dose of the BNT162b2 vaccine.

METHODS

Quantitative determination of immunoglobulin (Ig) G antibodies against the RBD of the S1 subunit of the spike protein of SARS-CoV-2 on the Alinity systems.

RESULTS

The highest levels of anti-RBD IgG were measured after 1 month from full vaccination (median: 1432 binding antibody units/ml [BAU/ml]); subsequently, a steep decrease (7.4-fold decrease) in IgG levels was observed at 6 months (median: 194.3 BAU/ml), with a further 2.5-fold decrease at 9 months (median: 79.3 BAU/ml). Furthermore, the same data, when analyzed for sex, showed significant differences between male and female participants at both 1 and 9 months from vaccination, but not at 6 months.

CONCLUSION

Our results confirm the tendency of anti-RBD antibodies to decrease over time, also when extending the analysis up to 9 months, and highlight a better ability of the female sex to produce antibodies 1 month and 9 months after vaccination. Overall, these data, obtained in a wide population of HCWs, support the importance of having increased the vaccine doses.

Determinants of COVID-19 vaccine acceptance in healthcare workers in Iran: National Survey

BACKGROUND AND AIM

It seems that acceptance of COVID-19 vaccination is the most effective way to tackle the COVID-19 pandemic now. Health care workers (HCWs) are one of the most important groups who are at risk for COVID-19 infection. This study aimed to assess the COVID-19 vaccine acceptance among HCWs in Iran and its determinants.

METHODS

A cross-sectional survey was carried out among 3600 HCWs in Iran. Data were collected through a self-administered questionnaire by a trained team from February to March 2021. Multi-stage cluster sampling method was used for selecting respondents of the study. Multivariate logistic regression analysis was used to determine the key factors of COVID-19 vaccine acceptance among participants. P-value < 0.05 was considered statistically significant.

RESULTS

Out of the 3536 respondents, 2191 (62.1%) intended to uptake the COVID-19 vaccine. Only about 10 percent of respondents said they did not trust any vaccine (domestic or foreign). Willing to accept a COVID-19 vaccine was relatively high among males, doctors, and those who had a history of hospitalization due to COVID-19 infection. The multivariate regression analysis showed respondents who were 40-50 years (aOR: 1.56; 95% CI: 1.47-1.66), had a history of COVID-19 infection (aOR: 0.85; 95% CI: 0.83-0.88), and hospitalized due to COVID-19 infection (aOR: 2.18; 95% CI: 1.97-2.39), were significantly associated with vaccine acceptance (p < 0.05).

CONCLUSION

Our study showed moderate acceptance of COVID-19 vaccination in the HCWs in the Islamic Republic of Iran. The most important factor in the acceptance of the COVID-19 vaccine by the health staff is having a history of hospitalization. Further training and justification of health personnel is needed to increase the acceptance of COVID 19 vaccine.

Seroprevalence in health care workers during the later phase of the second wave: Results of three hospitals in Serbia, prior to vaccine administration

BACKGROUND

Since the COVID-19 pandemic has started, Serbia has faced problems in implementing proper public health measures in the population, including non-pharmaceutical interventions, as well as protecting health care workers (HCWs) from disease, like all other countries. This study aimed to estimate COVID-19 seroprevalence and evaluate the risk perception of COVID-19 among HCWs in three different hospitals in Belgrade, Serbia: non-COVID hospital, Emergency Center (EC), and dedicated COVID hospital.

METHODS

A cross-sectional study was conducted in three hospitals during the second wave of the outbreak in Serbia, from June to early October. All staff in these hospitals were invited to voluntarily participate in blood sampling for IgG antibodies against SARS-CoV-2 and questionnaire testing. The questionnaire included socio-demographic characteristics, known exposure to COVID-19 positive persons, previous signs and symptoms related to COVID-19 infection since the outbreak had started in our country, and SARS-CoV-2 PCR testing.

RESULTS

The overall prevalence of SARS-CoV-2 antibody among 1580 HCWs was 18.3 % [95 % CI 16.4-20.3 %]. Significantly higher prevalence of HCWs with positive results for the serum IgG antibody test was observed in COVID hospital (28.6 %, 95 %CI: 24.0-33.6 %) vs. prevalence in the EC (12.6 %, 95 %CI: 10.1-15.4 %), and in the non-COVID hospital (18.3 %, 95 %CI: 15.2-26.7 %). The prevalence adjusted for declared test sensitivity and specificity would be 16.8 %; that is 27.4 % in COVID-19 hospital, 10.9 % in EC, and 16.8 % in non-COVID hospital. In multivariate logistic regression analysis, the independent predictors for seropositivity were working in COVID-hospital, the profession of physician, and the presence of the following symptoms: fever, shortness of breath, and anosmia/ageusia.

CONCLUSIONS

We found an overall seropositivity rate of 18.3 % and 16.0 % of the adjusted rate that is higher than seroprevalence obtained in similar studies conducted before vaccinations started. The possibility that patients in non-COVID dedicated hospitals might also be infectious, although PCR tested, imposes the need for the use of personal protective equipment also in non-COVID medical institutions.

A Cross-Sectional Study of Untoward Reactions Following Homologous and Heterologous COVID-19 Booster Immunizations in Recipients Seventeen Years of Age and Older

A booster dose after primary COVID-19 vaccination series was considered crucial after the emergence of the B.1.617.2 (Delta) and B.1.1.529 (Omicron) variants. Active surveillance was used to investigate reporting of adverse events post-booster dose of either of the licensed mRNA Comirnaty (Pfizer/BioNTech) or Spikevax (Moderna) vaccines in adult (17 years and older) recipients in central Italy. Eligible participants were enrolled and interviewed via phone using a structured questionnaire. Primary outcomes related to the occurrence of adverse events post-booster were stratified by vaccine, and frequency of local/systemic, mild/moderate/severe events. Of a total of 622 participants interviewed, 554 (89.1%) reported at least one adverse event (88.2% and 92.9% after the Comirnaty or Spikevax vaccine, respectively): 63.4% were female, and 78.5% aged 17 to 64 years, regardless of vaccine. 87.7% and 68.2% of all recipients described at least one local or systemic reaction, respectively: 97.3, 38.6 and 4.7% reported mild, moderate, or severe events, respectively. The most frequent adverse reactions were pain, redness, or swelling at the injection site and fatigue, while malaise and fever significantly occurred after the Comirnaty, and vomiting after the Spikevax booster. Compared to the primary vaccination, lymphadenopathy was more common after the booster (p < 0.001), especially after Comirnaty vaccine. The study findings revealed no serious or unexpected adverse events, and are in agreement with data available on booster dose for both mRNA vaccines. The transient, mild to moderate, and common to very common side reactions reported should be used to reassure potential recipients of the lack of safety concerns.

COVID-19 Vaccination in Health Care Workers in Italy: A Literature Review and a Report from a Comprehensive Cancer Center

The coronavirus disease 2019 pandemic still represents a global public health emergency, despite the availability of different types of vaccines that reduced the number of severe cases, the hospitalization rate and mortality. The Italian Vaccine Distribution Plan identified healthcare workers (HCWs) as the top-priority category to receive access to a vaccine and different studies on HCWs have been implemented to clarify the duration and kinetics of antibody response. The aim of this paper is to perform a literature review across a total of 44 studies of the serologic response to COVID-19 vaccines in HCWs in Italy and to report the results obtained in a prospective longitudinal study implemented at the Fondazione IRCCS Istituto Nazionale Tumori (INT) of Milan on 1565 HCWs. At INT we found that 99.81% of the HCWs developed an antibody response one month after the second dose. About six months after the first serology evaluation, 100% of the HCWs were still positive to the antibody, although we observed a significant decrease in its levels. Overall, our literature review results highlight a robust antibody response in most of the HCWs after the second vaccination dose. These figures are also confirmed in our institutional setting seven months after the completion of the cycle of second doses of vaccination.

A SARS-CoV-2 Outbreak Among Nursing Home Residents Vaccinated with a Booster Dose of mRNA COVID-19 Vaccine

This study describes a SARS-CoV-2 outbreak caused by the Delta (B.1.617.2) variant in a nursing home in Central Italy during October-November 2021. Trained interviewers collected data from residents, staff, and administration officers with an agreed informed consent procedure. Thirty-two (44.5%) out of 72 residents (median age 89 years) and six (26.1%) of 23 healthcare workers were found to be infected with SARS-CoV-2. Infections occurred more often among residents with a higher index of independence in daily living activities, suggesting an increased risk for those with more interactions. Twenty-five infected residents (78.1%) received the booster dose of mRNA anti-COVID-19 vaccine > 7 days before SARS-CoV-2 onset. Half of the infected residents had mild symptoms, and only three required hospitalisation, one of whom died from COVID-19 complications. The study underlines the effectiveness of a booster dose in providing a high protection against severe disease and hospitalisation even among vulnerable individuals infected with the Delta variant of concern.

Pfizer-BioNTech COVID-19 Vaccine (BNT162b2) Side Effects: A Systematic Review

Vaccinations prevented severe clinical complications of COVID-19. It was considered a vital component of living endemically with COVID-19. The Pfizer-BioNTech vaccine is the first mRNA-based vaccination that enhances immunity. Resulting in various adverse effects that may emerge after vaccination. This systematic review was undertaken to assess the Pfizer-BioNTech vaccine side effects by reviewing the previous studies. A total of 107 PubMed and Google Scholar publications were screened for Pfizer-BioNTech COVID-19 vaccine side effects. Fourteen articles met the study inclusion criteria. The included searching terms were a combination of “Pfizer vaccine and Side effects,” “BioNTech vaccine and side effects,” and “BNT162b2 vaccine and side effects,” as well as all synonyms. The total number of participants in the 14 studies was 10,632 participants. Average of the most frequent side effects of 14 studies were injection site pain 77.34%, fatigue 43%, muscle pain 39.67%, local swelling 33.57%, headache 33.27%, joint pain 25.75%, chills 18.34%, fever 18%, itching 9.38%, lymph nodes swelling 7.86%, nausea 7.58%, dyspnea 7.86%,and diarrhea 6.36%. The average side effects after the first dose were 79% compared with 84% after the second dose. The average occurs side effects in females at 69.8% compared with males 30.2%. Our study reveals that side effects after the Pfizer-BioNTech vaccine are common, but they are usually mild and self-limited. Local reactions like pain at the injection site are the most common. Anaphylactic shock or severe reactions are rare. We hope that our results will reassure the public that the benefits of vaccination far exceed the dangers. Also, help reduce vaccine hesitancy among individuals worried about vaccine safety and possible adverse effects.

Adverse Reactions to Anti-SARS-CoV-2 Vaccine: A Prospective Cohort Study Based on an Active Surveillance System

To date, Coronavirus disease (COVID-19) has caused high morbidity and mortality worldwide. To counteract the pandemic scenario, several vaccines against the etiological factor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were developed and tested. At the end of December 2020, BNT162b2 (Comirnaty, Pfizer-BioNTech) was the first and only authorized vaccine in Italy for selected categories, such as healthcare workers, fragile patients and people aged over 80 years old. To master our knowledge about BNT162b2 adverse reactions (ARs), an active surveillance system based on instant messaging was realized for voluntary participants who had been vaccinated at COVID-19 Vaccination Center of the Palermo University Hospital. Overall, 293 vaccinated persons were included in this study, which were more frequently healthcare workers (n = 207, 70.6% with a median age of 36 years, IQR = 29−55) followed by health professional students (n = 31, 10.6% with a median age of 27 years, IQR = 25−29), reporting 82.6% of at least one local or systemic AR. In details, the frequency of at least one local or systemic AR after the second dose of Comirnaty (n = 235, 80.2%) was statistically significant with higher value in comparison to the first one (n = 149, 50.9%; p < 0.001). However, local pain, swelling, joint pain and muscular pain after the second dose were the symptom causing a statistically significant working limitation. The youngest persons showed a higher risk to have either local or systemic ARs (aOR = 7.5, CI 95% = 2.9−18.9), while females had a higher risk of having systemic ARs (aOR = 1.8, CI 95% = 1.1−3.0). Despite the small sample examined, this active surveillance system by instant messaging seems to detect a higher ARs prevalence with respect to data obtained by the passive surveillance. Further studies could be required in order to optimize this clinical monitoring that could be considered an efficient and timely active surveillance.

Side effects among healthcare workers from a large Milan university hospital after second dose of BNT162b2 mRNA COVID-19 vaccine

BACKGROUND

In Italy, healthcare workers (HCWs) were among the first to receive COVID-19 vaccination. Aim of the present study is to evaluate frequency and severity of adverse events (AEs) following the second dose of BNT162b2 vaccine among HCWs of a large university hospital in Milan, Italy.

METHODS

One month after having received the second dose of vaccine, HCWs filled-in a form about type, severity, and duration of post-vaccination local and systemic symptoms. We calculated the overall frequency of AEs and used multivariable Poisson regression models (adjusted for sex, age, BMI, smoking, allergy history, previous SARS-CoV-2 infection, anti-hypertensive therapy, and occupation) to calculate risk ratios (RR) and 95% confidence intervals (CI) of AEs according to selected variables.

RESULTS

We included 3659 HCWs. Overall, 2801 (76.6%) experienced at least one local event, with pain at injection site being the most frequent (2788, 76.2%). Systemic events were reported by 2080 (56.8%) HCWs, with fatigue (52.3%), muscle pain (42.2%), headache (37.7%), joint pain (31.9%), and fever (26.2%) being the most frequent. Risks of systemic events were associated with female gender (RR=1.14, CI: 1.06-1.23), age (strong decrease with increasing age, p-trend<0.001), allergy history (RR=1.13, CI: 1.05-1.20), and current smoking (RR=0.90, CI: 0.84-0.97). HCWs with previous SARS-CoV-2 infection (even if symptomatic) were not at increased risk.

CONCLUSIONS

Both local and systemic acute effects after second dose of BNT162b2 vaccine were frequently reported. However, symptoms were mostly light/mild and of short duration. Thus, our findings support the safety of COVID-19 vaccination in adults in relatively good health.