Adverse reactions to the first and second doses of Pfizer-BioNTech COVID-19 vaccine among healthcare workers

IntroductionIn the current coronavirus infection 2019 (COVID-19) pandemic, the messenger RNA vaccines have been shown to help protect high-risk groups from COVID-19. Among healthcare workers vaccinated with Pfizer-BioNTech COVID-19 vaccine, a survey was conducted to analyze the relationship between the incidence and severity of adverse reactions after vaccination.MethodsWe conducted a prospective self-reported survey of adverse reactions among healthcare workers vaccinated with the Pfizer-BioNTech COVID-19 vaccine (Comirnaty®) in Japan. After the first and second dose of vaccine, local and systemic reactions for 8 days after vaccination were reported by volunteer participants using a website. After receiving vaccination, 374 respondents participated in this matched-pair study.ResultsBoth the incidence and severity of adverse reactions tended to be higher after the second vaccine dose than after the first dose. However, the incidence and numeric rating scale (NRS) score of muscle and skin pain were nearly the same after the first and second doses. In a comparison by sex, women had significantly higher incidence and NRS scores for adverse reactions such as headache, skin pain, erythema, and itching. The results also showed that younger age groups had higher incidence rates and NRS scores for all adverse reactions investigated, except for muscle pain, compared with older age groups.ConclusionSome adverse reactions to the Pfizer-BioNTech Comirnaty® COVID-19 vaccine showed gender and age differences. However, generally speaking, all side reactions disappear within a week. Therefore, these side reactions are not a significant concern in recommending vaccination.     

Adverse reactions to the BNT162b2 and mRNA-1273 mRNA COVID-19 vaccines in Japan

IntroductionThe BNT162b2 and mRNA-1273 COVID-19 vaccines are the main vaccines that have been used for mass vaccination in Japan. Information on adverse reactions to COVID-19 vaccines in the Japanese population is limited.MethodsWe conducted an online survey on self-reported adverse reactions in individuals who had received two doses of the BNT162b2 or mRNA-1273 vaccine. The incidence of adverse events after each dose of vaccine was investigated. Propensity score matching was used to compare the incidence of adverse reactions after the second dose of the BNT162b2 and mRNA-1273 vaccines.ResultsAfter the first and second doses of the BNT162b2 vaccine, and the first and second doses of the mRNA-1273 vaccine, 890, 853, 6401, and 3965 individuals, respectively, provided complete responses. Systemic reactions, including fever, fatigue, headache, muscle/joint pain, and nausea were significantly more common in females, individuals aged <50 years, and after the second dose. The incidence of injection site pain did not differ significantly according to the dose. The incidence of delayed injection site reactions after the first dose of mRNA-1273 vaccine was 3.9% and 0.8% among females and males, respectively, and 10.6% among females aged 40–69 years. Local and systemic reactions after the second dose, including fever, fatigue, headache, muscle/joint pain, nausea, and skin rash were more common in individuals who had received the mRNA-1273 vaccine.ConclusionsAdverse reactions were more frequently reported in females, younger individuals, and after the mRNA-1273 vaccine.     

Post-COVID-19 vaccination arm pain diagnosed as complex regional pain syndrome: A case report

As the vaccination efforts against the coronavirus disease-2019 (COVID-19) continue, more patients are likely to present with complications related to COVID-19 vaccination. We describe the first reported case of complex regional pain syndrome (CRPS), involving the upper extremities, that occurred after COVID-19 vaccination. The patient presented with acute-onset severe arm pain and swelling following vaccine administration. Based on the clinical, electrodiagnostic, and radionuclide three-phase bone scan findings, the patient was diagnosed with postvaccination CRPS. The COVID-19 vaccine possibly elicited an immune-mediated inflammatory response to the injected antigen in the patient, who was predisposed to CRPS due to inflammatory immunity. The COVID-19 vaccine elicited an immune-mediated inflammatory response to the injected antigen, resulting in CRPS following COVID-19 vaccination.     

Immunogenicity and Safety of SpikoGen,an Adjuvanted Recombinant SARS-CoV-2 Spike Protein,as a Heterologous Third Booster Dose in Kidney Transplant Patients: A Single-arm Clinical Trial

PurposeStudies have found that immunocompromised patients have suboptimal responses to COVID-19 vaccines, leading to approval of a need for booster doses in this population. SpikoGen® is a subunit recombinant spike protein vaccine combined with Advax-CpG55.2? adjuvant to protect against COVID-19. Previous clinical trials found this vaccine to be tolerable, immunogenic, and efficacious in reducing the risk of COVID-19, including severe disease. However, the effects of this vaccine have not been assessed in immunocompromised patients. This study sought to assess the immunogenicity and safety of the SpikoGen vaccine as a third booster dose in patients undergoing kidney transplant who were receiving immunosuppressive therapy and had received their primary vaccination based on an inactivated whole virus platform (Sinopharm).MethodsThis single-arm trial was performed with 43 patients undergoing kidney transplant. The participants received a single booster dose of the SpikoGen vaccine 1 to 3 months after primary vaccination with 2 doses of the Sinopharm vaccine. Immunogenicity assessments were performed at baseline and 30 days after the booster dose. The primary outcomes were seroconversion rates of anti-S₁ and surrogate virus neutralizing antibodies. Safety outcomes included the incidence of solicited and unsolicited adverse events in the 7 days and 1 month after the booster dose, respectively.FindingsThe SpikoGen vaccine induced positive humoral and cellular responses 30 days after the booster dose in those patients who were seropositive or seronegative after 2 primary doses of the Sinopharm vaccine. Thirty days after the SpikoGen vaccine booster, seroconversion rates were 35.29% (95% CI, 19.75%–53.51%) to anti-S₁ and 29.41% (95% CI, 13.27%–46.57%) to surrogate neutralizing antibodies. The most common local and systemic reported solicited adverse events were injection site pain and fatigue, which were largely mild and transient. No serious adverse events were reported.ImplicationsA single booster dose of SpikoGen vaccine given 1 to 3 months after primary vaccination with 2 doses of Sinopharm vaccine induced positive humoral and cellular immune responses in immunosuppressed patients undergoing renal transplant, thereby achieving spike antibody levels predictive of protection. This study was performed as a single-center study, and it will be important for future large multicenter studies to extend these results to other immunocompromised patient groups.     

Bell’s palsy after inactivated COVID-19 vaccination in a patient with history of recurrent Bell’s palsy: A case report

BACKGROUNDWith rapid and extensive administration of inactivated coronavirus disease 2019 (COVID-19) vaccine to the general population in China, it is crucial for clinicians to recognize neurological complications or other side effects associated with COVID-19 vaccination.CASE SUMMARYHere we report the first case of Bell’s palsy after the first dose of inactivated COVID-19 vaccine in China. The patient was a 36-year-old woman with a past history of Bell’s palsy. Two days after receiving the first dose of the Sinovac Life Sciences inactivated COVID-19 vaccine, the patient developed right-side Bell’s palsy and binoculus keratoconjunctivitis. Prednisone, artificial tears and fluorometholone eye drops were applied. The patient’s symptoms began to improve by day 7 and resolved by day 54.CONCLUSIONAs mRNA COVID-19 vaccine trials reported cases of Bell’s palsy as adverse events, we should pay attention to the occurrence of Bell’s palsy after inactivated COVID-19 vaccination. A history of Bell’s palsy, rapid increase of immunoglobulin M and immunoglobin G-specific antibodies to severe acute respiratory syndrome coronavirus 2 may be risk factors for Bell‘s palsy after COVID-19 vaccination.     

Standardization of upper limb exercises to improve radiation therapy for breast cancer,a conceptual literature review

IntroductionMany patients with breast cancer are left with upper arm mobility dysfunction following surgery. Despite the beneficial effects of upper limb exercises on shoulder dysfunction, radiation therapists still do not widely encourage patients to participate in arm exercises after surgery. This conceptual literature review synthesizes evidence on how patients with breast cancer that participate in upper limb exercises after surgery have improved arm mobility which could result in a more consistent arm position during radiation therapy.MethodsA literature search was performed in the PubMed, Athabasca University Library, and Google Scholar databases to identify articles that evaluated the effect of upper limb exercises on patients’ arm mobility and range of motion after breast cancer surgery, and the impact of arm position on anatomy during radiation therapy. Sixteen studies were included in the conceptual review synthesis.ResultsThe studies were heterogeneous in terms of the utilized exercise methods and the upper limb related outcomes measured. Twelve studies demonstrated that upper arm exercises are an effective intervention in restoring arm mobility and decreasing pain in women with breast cancer. Additionally, four studies showed that differences in arm rotation affect the breast region's anatomy, which could result in set-up errors during radiation therapy.ConclusionThe effectiveness of radiation therapy for breast cancer treatment relies on women to reproduce their shoulder position each day. Any inability to replicate the arm position due to mobility issues can affect the accuracy of the dose delivered and, ultimately, the treatment outcome. Therefore, upper limb exercises should be recommended by radiation therapists to their patients before or during radiation therapy to improve patient comfort and the accuracy of treatment. Additionally, upper limb exercise standards need to be developed for patients with breast cancer and implemented by radiation therapists.     

Worldwide association of lifestyle-related factors and COVID-19 mortality

BackgroundSeveral lifestyle-related factors, such as obesity and diabetes, have been identified as risk factors for Coronavirus disease 2019 (COVID-19) mortality. The objective of this study was to examine the global association between lifestyle-related factors and COVID-19 mortality using data from each individual country.MethodsThe association between prevalence of seven lifestyle-related factors (overweight, insufficient physical activity, smoking, type-2 diabetes, hypertension, hyperlipidaemia, and age over 65) and COVID-19 mortality was assessed by linear and multivariable regression among 186 countries. The cumulative effect of lifestyle-related factors on COVID-19 mortality was assessed by dividing countries into four categories according to the number of lifestyle-related factors in the upper half range and comparing the mean mortality between groups.ResultsIn linear regression, COVID-19 mortality was significantly associated with overweight, insufficient physical activity, hyperlipidaemia, and age ≥65. In multivariable regression, overweight and age ≥65 demonstrated significant association with COVID-19 mortality (p = .0039, .0094). Countries with more risk factors demonstrated greater COVID-19 mortality (P for trend <.001).ConclusionLifestyle-related factors, especially overweight and elderly population, were associated with increased COVID-19 mortality on a global scale. Global effort to reduce burden of lifestyle-related factors along with protection and vaccination of these susceptible groups may help reduce COVID-19 mortality.     

Incidence of adverse reactions to COVID-19 vaccination:A meta-analysis of randomized controlled trials

Objective:To systematically evaluate the incidence of adverse reactions to coronavirus disease 2019(COVID-19)vaccination.Methods:We systematically searched PubMed,Embase,The Cochrane Library,Web of Science,CNKI,WanFang Data,and VIP Database from the inception of each database to August 31,2021.Randomized controlled clinical trials(RCTs)on the safety of different types of COVID-19 vaccines were retrieved and analyzed.A random or fixed-effects model was used with an odds ratio as the effect size.The quality of each reference was evaluated.The incidence of the adverse reactions of the placebo group and the vaccination group was compared.Heterogeneity and publication bias were taken care of by meta-regression and sub-group analyses.Results:A total of 13 articles were included,with 81287 subjects.Compared with the placebo group,the vaccination group showed a higher combined risk ratio(RR)of total adverse reactions(RR=1.67,95%CI:1.46-1.91,P<0.01),local adverse reactions(RR=2.86,95%CI:2.11-3.87,P<0.01),systemic adverse reactions(RR=1.25,95%CI:0.92-1.72,P=0.16),pain(RR=2.55,95%CI:1.75-3.70,P<0.01),swelling(RR=4.16,95%CI:1.71-10.17,P=0.002),fever(RR=2.34,95%CI:1.84-2.97,P<0.01),fatigue(RR=1.36,95%CI:1.32-1.41,P<0.01)and headache(RR=1.22,95%CI:1.18-1.26,P<0.01).The subgroup analysis showed the incidence of adverse reactions of the vaccination group after injection of the three COVID-19 vaccines(inactivated viral vaccines,mRNA vaccines and adenovirus vector vaccines)was higher than that of the placebo group,and the difference between the placebo group and the vaccination group in the mRNA vaccine subgroup and the adenovirus vector vaccine subgroup was statistically significant(P<0.01).The incidence of adverse reactions after injection of COVID-19 vaccine in subgroups of different ages was significantly higher than that in the placebo group(P<0.01).Conclusions:COVID-19 vaccines have a good safety,among which adenovirus vector vaccine has the highest incidence of adverse reactions.Both adolescents and adults vaccinated with novel coronavirus vaccine have a certain proportion of adverse reactions,but the symptoms are mild and can be relieved by themselves.Our meta-analysis can help boost global awareness of vaccine safety,promote mass vaccination,help build regional and global immune barriers and effectively curb the recurrency of COVID-19.     

Effects of scapular stabilization and upper limb proprioception as an adjunct to cervical stabilization in chronic neck pain patients: A randomized controlled trial

BackgroundChronic neck pain is a prevalent health condition and a leading cause of disability worldwide. Prompt therapeutic measures are required to overcome this condition.ObjectivesTo evaluate the efficacy of incorporation of scapular stabilization and upper limb proprioceptive exercises to cervical stabilization exercises in patients with chronic neck pain (CNP).DesignA single-blinded randomized controlled design.MethodsA sample of convenience was deployed to recruit twenty-eight patients having CNP (18–45 years) and was randomized into two groups: group A (cervical stabilization exercises group) and group B (scapular stabilization and upper limb proprioceptive exercises group + cervical stabilization exercises). Pain intensity, disability, sleep quality, quality of life, scapular muscles strength and proprioception were assessed at 4 weeks follow up to determine the efficacy of the intervention.ResultsA mixed model ANOVA was used. A statistically significant (p < 0.05) group by time interaction for pain intensity (p = 0.000), scapular muscles strength of all muscles (p = 0.000) was observed. Significant group interaction for absolute error (p = 0.00), for pain (p = 0.001), disability (p = 0.04) and scapular muscle's strength (p = 0.000) was also demonstrated.ConclusionThe results indicated that scapular stabilization and upper limb proprioceptive exercises when combined with cervical stabilization exercises are more beneficial in alleviating pain and disability and improving scapular muscle strength and proprioception in patients with CNP.     

Peripheral and Central Adaptations After a Median Nerve Neuromobilization Program Completed by Individuals With Carpal Tunnel Syndrome: An Exploratory Mechanistic Study Using Musculoskeletal Ultrasound Imaging and Transcranial Magnetic Stimulation

ObjectiveNeuromobilization exercises are increasingly advocated in the conservative management of individuals with carpal tunnel syndrome (CTS), as they may mitigate CTS-related signs and symptoms via potential peripheral (ie, musculoskeletal) and central (ie, neurophysiological) adaptations. However, the mechanisms underlying these adaptations have not been studied extensively. Hence, this exploratory and mechanistic study aims to evaluate the potential peripheral and central adaptations that may result in individuals with CTS who have completed a neuromobilization program.MethodsFourteen individuals with CTS were evaluated before and 1 week after the completion of a 4-week neuromobilization program that incorporated median nerve sliding exercises. Pain and upper limb functional abilities were assessed using standardized questionnaires. The biological integrity and mechanical properties of the median nerve and the corticospinal excitability were quantified using musculoskeletal ultrasound imaging and transcranial magnetic stimulation, respectively.ResultsUpon completion of the program, participants reported both large and moderate improvements in pain (P ≤ .03) and upper limb functional abilities (P = .02), respectively. The biological integrity and mechanical properties of the median nerve remained unchanged (P ≥ .22), whereas a small significant increase in corticospinal excitability (P = .04) was observed.ConclusionThe proposed neuromobilization program appears promising to improve pain and upper limb functional abilities in individuals with CTS. These improvements may be preferentially mediated via central, rather than peripheral, adaptations. Future studies, especially with a larger sample size, longer intervention duration, and additional measurement times, are needed to strengthen current evidence.     

Relationship between pain and upper limb movement in patients with chronic sternal instability following cardiac surgery

Physiotherapists routinely prescribe upper limb exercises for patients who have undergone a median sternotomy during cardiac surgery. It is not currently known whether upper limb exercises should be unilateral or bilateral and conducted with or without additional loading to minimise pain and further sternal separation in patients with sternal instability. Eight patients who had chronic sternal instability after cardiac surgery were included in this study. During a selected regimen of upper limb exercises, the amount of sternal separation at different vertical points on the sternum was measured by ultrasound. The amount of sternal separation was not related to type of upper limb activity, but both unilateral and unilateral loaded positions were found to be significantly associated with sternal pain (p = 0.009). In this group of patients with chronic sternal instability, bilateral upper limb movements were significantly less associated with sternal pain than unilateral movements.     

SARS-CoV-2 infection and vaccination trigger long-lived B and CD4+ T lymphocytes with implications for booster strategies

BACKGROUNDImmunization against SARS-CoV-2, the causative agent of COVID-19, occurs via natural infection or vaccination. However, it is currently unknown how long infection- or vaccination-induced immunological memory will last.METHODSWe performed a longitudinal evaluation of immunological memory to SARS-CoV-2 up to 1 year after infection and following mRNA vaccination in naive individuals and individuals recovered from COVID-19 infection.RESULTSWe found that memory cells are still detectable 8 months after vaccination, while antibody levels decline significantly, especially in naive individuals. We also found that a booster injection is efficacious in reactivating immunological memory to spike protein in naive individuals, whereas it was ineffective in previously SARS-CoV-2–infected individuals. Finally, we observed a similar kinetics of decay of humoral and cellular immunity to SARS-CoV-2 up to 1 year following natural infection in a cohort of unvaccinated individuals.CONCLUSIONShort-term persistence of humoral immunity, together with the reduced neutralization capacity versus the currently prevailing SARS-CoV-2 variants, may account for reinfections and breakthrough infections. Long-lived memory B and CD4⁺ T cells may protect from severe disease development. In naive individuals, a booster dose restored optimal anti-spike immunity, whereas the needs for vaccinated individuals who have recovered from COVID-19 have yet to be defined.FUNDINGThis study was supported by funds to the Department of Experimental and Clinical Medicine, University of Florence (Project Excellence Departments 2018–2022), the University of Florence (project RICTD2122), the Italian Ministry of Health (COVID-2020-12371849), and the region of Tuscany (TagSARS CoV 2).     

Relationship between pain and upper limb movement in patients with chronic sternal instability following cardiac surgery

Physiotherapists routinely prescribe upper limb exercises for patients who have undergone a median sternotomy during cardiac surgery. It is not currently known whether upper limb exercises should be unilateral or bilateral and conducted with or without additional loading to minimise pain and further sternal separation in patients with sternal instability. Eight patients who had chronic sternal instability after cardiac surgery were included in this study. During a selected regimen of upper limb exercises, the amount of sternal separation at different vertical points on the sternum was measured by ultrasound. The amount of sternal separation was not related to type of upper limb activity, but both unilateral and unilateral loaded positions were found to be significantly associated with sternal pain (p = 0.009). In this group of patients with chronic sternal instability, bilateral upper limb movements were significantly less associated with sternal pain than unilateral movements.     

First-dose mRNA vaccination is sufficient to reactivate immunological memory to SARS-CoV-2 in subjects who have recovered from COVID-19

The characterization of the adaptive immune response to COVID-19 vaccination in individuals who recovered from SARS-CoV-2 infection may define current and future clinical practice. To determine the effect of the 2-dose BNT162b2 mRNA COVID-19 vaccination schedule in individuals who recovered from COVID-19 (COVID-19–recovered subjects) compared with naive subjects, we evaluated SARS-CoV-2 Spike–specific T and B cell responses, as well as specific IgA, IgG, IgM, and neutralizing antibodies titers in 22 individuals who received the BNT162b2 mRNA COVID-19 vaccine, 11 of whom had a previous history of SARS-CoV-2 infection. Evaluations were performed before vaccination and then weekly until 7 days after second injection. Data obtained clearly showed that one vaccine dose is sufficient to increase both cellular and humoral immune response in COVID-19–recovered subjects without any additional improvement after the second dose. On the contrary, the second dose proved mandatory in naive subjects to further enhance the immune response. These findings were further confirmed at the serological level in a larger cohort of naive (n = 68) and COVID-19–recovered (n = 29) subjects, tested up to 50 days after vaccination. These results question whether a second vaccine injection in COVID-19–recovered subjects is required, and indicate that millions of vaccine doses may be redirected to naive individuals, thus shortening the time to reach herd immunity.     

Thymosin as a possible therapeutic drug for COVID-19: A case report

BACKGROUNDThere are no effective antiviral therapies for coronavirus disease 2019 (COVID-19) at present. Although most patients with COVID-19 have a mild or moderate course of disease, up to 5%-10% of patients may have a serious and potentially life-threatening condition, indicating an urgent need for effective therapeutic drugs. The therapeutic effect of thymosin on COVID-19 has not been previously studied. In this paper, for the first time we report a case of thymosin treatment of COVID-19.CASE SUMMARYA 51-year-old man with imported COVID-19 was admitted with definite symptoms of chest tightness, chest pain, and fatigue. The polymerase chain reaction results for severe acute respiratory syndrome coronavirus 2 were negative. The antibody test was positive, confirming the diagnosis of COVID-19. As many orally administered drugs were not well tolerated due to gastrointestinal symptoms, an emergency use of thymosin, a polypeptide consisting of 28 amino acids, was administered by injection. Finally, after the implementation of the treatment program, symptoms and lung imaging improved significantly.CONCLUSIONIn this case report, it is confirmed that thymosin may help alleviate the severity of COVID-19 symptoms.     

Analysis of older adults visiting the emergency department with fever as a suspected Covid-19 vaccine-related adverse reaction: A retrospective multicenter study

IntroductionAfter COVID-19 vaccination was initiated, the number of patients visiting the emergency department (ED) with vaccine-related adverse reactions increased. We investigated the clinical features of older adults (aged 65 years and older) visiting the ED with self-reported COVID-19 postvaccination fever.MethodsWe conducted a retrospective observational study at three EDs between March 2021 and September 2021. Patients who reported adverse reactions, fever (≥37.5 °C) and/or febrile sensation or rigors following COVID-19 vaccination were included. The demographic and clinical data of these patients were collected by reviewing their medical records.ResultsA total of 562 patients were selected, and 396 (70.5%) were female. The older adult group included 155 (27.6%) patients, and the median age was 75 (69–79 years). The older adults less frequently had a fever (≥37.5 °C) upon ED presentation (75.5% vs. 85.7%, respectively), used more emergency medical services (43.9% vs. 18.7%, respectively), and visited an ED more frequently during early hours (00:00–06:00) (31% vs. 20.1%, respectively) compared to the younger adults (p = 0.004, p < 0.001 and p = 0.036). Fewer older adults visited an ED within 2 days of fever onset (73.5% vs. 84%) (p = 0.012), and more older adults were admitted for medical conditions other than vaccine-related adverse reactions (32.9% vs. 4.2%) (p < 0.001). Older adults received more thorough testing (laboratory and imaging tests). Among the older adults, the admission rate was associated with age (p = 0.003).ConclusionOlder adults presenting with fever as an adverse reaction following COVID-19 vaccination less frequently had a fever upon visiting the ED, required more ED testing, and had higher admission rates for non-vaccination-related medical conditions.     

Delayed headache after COVID-19 vaccination: a red flag for vaccine induced cerebral venous thrombosis

BackgroundHeadache is a frequent symptom following COVID-19 immunization with a typical onset within days post-vaccination. Cases of cerebral venous thrombosis (CVT) have been reported in adenovirus vector-based COVID-19 vaccine recipients.FindingsWe reviewed all vaccine related CVT published cases by April 30, 2021. We assessed demographic, clinical variables and the interval between the vaccination and onset of headache. We assessed whether the presence of headache was associated with higher probability of death or intracranial hemorrhage.We identified 77 cases of CVT after COVID-19 vaccination. Patients’ age was below 60 years in 74/77 (95.8%) cases and 61/68 (89.7%) were women. Headache was described in 38/77 (49.4%) cases, and in 35/38 (92.1%) was associated with other symptoms. Multiple organ thrombosis was reported in 19/77 (24.7%) cases, intracranial hemorrhage in 33/77 (42.9%) cases and 19/77 (24.7%) patients died. The median time between vaccination and CVT-related headache onset was 8 (interquartile range 7.0–9.7) days. The presence of headache was associated with a higher odd of intracranial hemorrhage (OR 7.4; 95% CI: 2.7–20.8, p < 0.001), but not with death (OR: 0.51, 95% CI: 0.18–1.47, p = 0.213).ConclusionDelayed onset of headache following an adenovirus vector-based COVID-19 vaccine is associated with development of CVT. Patients with new-onset headache, 1 week after vaccination with an adenovirus vector-based vaccine, should receive a thorough clinical evaluation and CVT must be ruled out.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-021-01324-5.     

Antibody responses induced by the BNT162b2 mRNA COVID-19 vaccine in healthcare workers in a single community hospital in Japan

IntroductionThe effectiveness of several vaccines against coronavirus disease (COVID-19) has been reported in the real-world setting. However, it is still unknown how long antibodies persist following vaccination and whether or not the persistence of antibodies has a protective effect against COVID-19.MethodsHealthcare workers who had received two doses of the BNT162b2 mRNA COVID-19 vaccine were enrolled, and a single-center study was conducted at the National Hospital Organization Hakodate National Hospital. Serum samples from all participants were collected 13–21 weeks (median: 20 weeks) after the second dose of vaccination. The antibody titers were measured using an electrochemiluminescence immunoassay (Elecsys® Anti-SARS-CoV-2 S). Data on characteristics of the participants were gathered from patient records and interview sheets.ResultsA total of 401 participants, among whom 70.1% were women and the median age was 42 years, were evaluated in this study. None of the participants had a definite COVID-19 history, and all participants who received complete vaccination showed positive antibody titers. The antibody titer was observed to be higher in participants with younger age (p < 0.001) and those who were females (p = 0.028). Despite the higher risk of infection than that of the general public, no vaccinated staff developed breakthrough infections.ConclusionsThis study demonstrates the significant contribution of the BNT162b2 vaccine in the acquisition of anti-SARS-CoV-2S antibodies; therefore, the general population should benefit from these two vaccine doses, which are expected to be protective for at least five months.