The opportunity for massage therapy development for relieving long COVID symptoms: a literature review

The COVID-19 pandemic situation affected population health and lifestyle not only for a short period but also long period. Long COVID symptoms is a long-term illness after COVID condition. Long COVID symptoms greatly affected to quality of life of patients. Massage is a unique treatment form of alternative medicine that can promote health in various dimensions. From the previous studies, massage has affected to Long COVID mechanism via anti-inflammatory process, immune system enhancing process, and hormone level balancing that related to Long COVID symptoms as well as being able to reduce the symptoms of the long COVID symptoms. The study about the efficacy and safety of massage against Long COVID symptoms is the essential approach to increase the value of massage and develop health services in the future.

Analysis of avian disease transmission risk and prevention measures in China

Many zoonotic diseases are found in wild animals and present a serious risk to human health, in particularly the virus carried by birds flying freely around the world is hard to control. There are three main bird migration routes which cover the most areas of China. It is important to investigate and fully understand the types of avian transmitted diseases in key areas on the bird migration routines and its impacts on both birds and human health. However, no literature is available in how about the risk of virus carried by migrating birds, and how to predict and reduce this risk of virus spreading to human being so far. In this paper, we first reviewed the main pathogen types carried by birds, including coronaviruses, influenza viruses, parasites, Newcastle disease virus (NDV), etc., and then discussed the spread risk of avian viruses to human being and animals in key areas of biosafety prevention. We also analyzed and discussed the risk of cross-spread of diseases among different bird species in nature reserves located on bird migration routes which provide sufficient food sources for migratory birds and attract numerous birds. Diseases transmitted by wild birds pose a serious threat to poultry farms, where high density of poultry may become avian influenza virus (AIV) reservoirs, cause a risk of avian influenza outbreaks. Airports are mostly built in suburban areas or remote areas with good ecological environment. There are important transit places for bird migration and densely populated areas, which have serious risk of disease transmission. Finally, this paper puts forward the following prevention suggestions from three aspects. First, establish and improve the monitoring and prediction mechanism of migratory birds, and use laser technology to prevent contact between wild birds and poultry. Second, examine and identify virus types carried by birds in their habitats and carry out vaccination. Third, protect the ecological environment of bird habitat, and keep wild birds in their natural habitat, so as to reduce the contact between wild birds and human and poultry, and thus reduce the risk of virus transmission.

Progress in understanding the health promoting effect of egg yolk immunoglobulin

As an important immuneoactive component in eggs, yolk immunoglobulin (IgY) shows great competitiveness in research and production due to its good stability, high safety, low cost, easy availability, strong immune activity, and no drug resistance. This article highlights the significant advantages of IgY as a good antibiotic substitute in the prevention and treatment of viral and bacterial diseases. Also, IgY has great potential in the regulation of nutrient metabolism balance, intestinal microflora and immune homeostasis by affecting key rate-limiting enzymes, and relevant receptors and inflammatory factors specifically. Proper diet and targeted delivery of foodborne IgY may be a new perspective on inflammation regulation, disease control, nutritional balance or homeostasis, and oral microencapsulated IgY is expected to be a new approach against increasing public health emergencies (such as COVID-19 pandemic).

High seroprevalence of anti-SARS-CoV-2 antibodies in the capital of Chad

Background. Since the start of the COVID-19 pandemic, Chad has had 7,417 confirmed cases and 193 deaths, one of the lowest in Africa. Objective. This study assessed SARS-CoV-2 immunity in N'Djamena. Methods. In August-October 2021, eleven N'Djamena hospitals collected outpatient data and samples. IgG antibodies against SARSCoV- 2 nucleocapsid protein were identified using ELISA. "Bambino Gesu" Laboratory, Rome, Italy, performed external quality control with chemiluminescence assay. Results. 25-34-year-old (35.2%) made up the largest age group at 31.9 12.6 years. 56.4% were women, 1.3 women/men. The 7th district had 22.5% and the 1st 22.3%. Housewives and students dominated. Overall seroprevalence was 69.5% (95% CI: 67.7-71.3), females 68.2% (65.8-70.5) and males 71.2% (68.6-73.8). >44-year-old had 73.9% seroprevalence. Under-15s were 57.4% positive. Housewives (70.9%), civil servants (71.5%), and health workers (9.7%) had the highest antibody positivity. N'Djamena's 9th district had 73.1% optimism and the 3rd district had 52.5%. Seroprevalences were highest at Good Samaritan Hospital (75.4%) and National General Referral Hospital (74.7%). Conclusion. Our findings indicate a high circulation of SARS-CoV- 2 in N'Djamena, despite low mortality and morbidity after the first two COVID-19 pandemic waves. This high seroprevalence must be considered in Chad's vaccine policy.

WASHINGTON REPORT

FNIH will manage an ACTIV steering committee to develop an inventory of potential candidates, launch master protocols with a single control arm, and set criteria for ranking potential candidates for first-wave and subsequent evaluation. [...]a third group will tap NIH's extensive clinical trial network infrastructure to build capacity for expediting trials and to study different populations and disease stages. ?o advance vaccine development, another ACTIV group will form a collaborative framework to map epitopes and develop assays, establish protocols for sampling and immunological analyses, collect clinical data on immunological responses and endpoints, and engage with regulators on surrogate endpoints for clinical evaluation. Jill Wechsler MULTIPLE WEBSITES IDENTIFY AND TRACK RESEARCH ON COVID Widespread research activity is available from these and other organizations: * The University of Oxford Center for Evidence-Based Medicines lists more than 1000 clinical trials at http:// covid19.trialstracker.net/index.html * Bill & Melinda Gates Foundation with Cytel identifies more than 600 trials in the US and other regions at https://covid19-trialscom * TranspariMed offers a guide to multiple trials at https://www.transparimed.org/ * Bi°Century tracks vaccines and therapeutics in its COVID-19 Resource Center, https://www.biocentury.com/ clinical-vaccines-and-therapies * World Health Organization: https://www. who.int/emergencies/diseases/novelcoronavirus-2019/global-researchon-novel-coronavirus-2019-ncov/ * Regulatory Affairs Professionals Society: https://www.raps.org/newsand-articles/news-articles/2020/3/ covid-19-therapeutics-tracker

Recent progresses in rapid detection of novel coronavirus SARS-CoV-2

The global pandemic coronavirus pneumonia (COVID-19), the disease infected by the new coronavirus (SARS-CoV-2), is extremely contagious. It is mainly spread among people through respiratory droplets, aerosols, direct or indirect contact, fecal-oral transmission, and cold chain transportation. Especially, patients who are in the incubation period or have no obvious symptoms already have the ability to infect others. SARS-C0V-2 is a positive-sense single-stranded RNA virus, with a single linear RNA segment. Each SARS-CoV-2 virion is 60-140 mm in diameter. Like other coronaviruses, SARS-CoV-2 has four structural proteins, known as the spike (S), envelope(E), membrane (M), and nucleocapsid (N) proteins. To date, a variety of detection methods for the SARS-CoV-2 have been developed based on the virus structural basis and 'etiological characteristics, which would provide an effective guarantee for the diagnosis of COVID-19 patients and the control of the epidemic. In order to help for the early diagnosis and prevention of COVID-19, the pathogenic characteristics and recent progresses of detection base on nucleic acid, immunology and biosensors of the SARS-CoV-2 are reviewed in this paper.

Introduction to the Special Issue on Immunology

For many science teachers and science teacher educators, COVID-19 made clear a need to focus on the socioscientific issues. [...]it subverts and undercuts the goals of having inquiry in the standards as it was intended. [...]the lack of ability to address things outside the standards leads to a lesser engagement with inquiry as it becomes more a poorly implemented default than a carefully crafted learning objective. [...]it is one with no explicit link to the NGSS. [...]teachers have made a choice either to teach about IDE outside the content mandated by the NGSS-perhaps under the cover of inquiry-or to avoid instruction on the most relevant and immediate socioscientific issue in students' lives. [...]current events have prompted a resurgence of this discussion (Zucker and Noyce 2020). [...]examination and discussion of how the NGSS might be understood or implemented in more adaptive ways is both timely and productive for scholars and policy makers who have a vested interest in the sufficiency or potential shortcomings of the dominant set of science education standards.

POSSIBLE ROLE OF PEPTIDE EPITOPES OF COVID-19 BNT-162B2 MRNA VACCINE IN FOMENTING AUTOIMMUNITY: AN IN SILICO ANALYSIS

BackgroundFollowing the launch of the global COVID-19 vaccination campaign, there have been increased reports of autoimmune diseases developing de novo following vaccination. These cases include rheumatoid arthritis, autoimmune hepatitis, immune thrombotic thrombocytopenia, and connective tissue diseases. Nevertheless, COVID-19 vaccines are considered safe for patients with autoimmune diseases and are strongly recommended.ObjectivesThe aim of this in silico analysis is to investigate the presence of protein epitopes encoded by the BNT-162b2 mRNA vaccine, one of the most commonly administered COVID-19 vaccines, that could elicit an aberrant adaptive immune response in predisposed individuals.MethodsThe FASTA sequence of the protein encoded by the BNT-162b2 vaccine was retrieved from http://genome.ucsc.edu and used as a key input to the Immune Epitope Database and Analysis Resource (www.iedb.org). Linear peptides with 90% BLAST homology were selected, and T-cell, B-cell, and MHC ligand assays without MHC restriction were searched and evaluated. HLA-disease associations were screened on the HLA-SPREAD platform (https://hla-spread.igib.res.in) by selecting only positive markers.ResultsA total of 183 epitopes were found, corresponding to 178 SARS-CoV-2 and 5 SARS-CoV spike epitopes, respectively. Results were obtained from 22 T-cell assays, 398 B-cell assays, and 2 MHC ligand assays. Complementary receptors included 1080 T-cell receptors and 0 B-cell receptors.Specifically, the IEDB_epitope:1329790 (NATNVVIKVCEFQFCNDPFLGVYY) was shown to bind to HLA-DRB1*15:02 and HLA-DRB1*15:03 alleles, whereas the IEDB_epitope:1392457 (TKCTLKSFTVEKGIYQTSNFRVQPT) was reported to bind to HLA-DRB1*07:01, HLA-DRB1*03:01, HLA-DRB3*01:01, and HLA-DRB4*01:01 alleles. The HLA alleles detected were found to be positively associated with various immunological disorders (Table 1).Table 1.MHC-restricted epitopes of the BNT-162b2 vaccine and potentially associated immunological conditionsEpitopeAssayMHC moleculeAssociated disease (population)NATNVVIKVCEFQFCNDPFLGVYY + OX(C10)cellular MHC/mass spectrometry ligand presentationHLA-DRB1*15:02Takayasu arteritis (Japanese) Arthritis (Taiwanese) Scleroderma (Japanese) Colitis (Japanese)HLA-DRB1*15:03Systemic lupus erythematosus (Mexican American)TKCTLKSFTVEKGIYQTSNFRVQPT + SCM(K2)as aboveHLA-DRB1*07:01Allergy, hypersensitivity (Caucasian)HLA-DRB1*03:01Type 1 diabetes (African) Sarcoidosis, good prognosis (Finnish)HLA-DRB3*01:01Graves' disease (Caucasian) Thymoma (Caucasian) Sarcoidosis (Scandinavian) Autoimmune hepatitis (Caucasian)HLA-DRB4*01:01Vitiligo (Saudi Arabian)ConclusionSimilar to the SARS-CoV-2 spike protein, the protein product of the BNT-162b2 mRNA vaccine contains immunogenic epitopes that may trigger autoimmune phenomena in predisposed individuals. Genotyping for HLA alleles may help identify at-risk individuals. However, further research is needed to elucidate the underlying mechanisms and potential clinical implications.References[1]Vita R, Mahajan S, Overton JA et al. The Immune Epitope Database (IEDB): 2018 update. Nucleic Acids Res. 2019 Jan 8;47(D1):D339-D343. doi: 10.1093/nar/gky1006.[2]Dholakia D, Kalra A, Misir BR et al. HLA-SPREAD: a natural language processing based resource for curating HLA association from PubMed s. BMC Genomics 23, 10 (2022). https://doi.org/10.1186/s12864-021-08239-0[3]Parker R, Partridge T, Wormald C et al. Mapping the SARS-CoV-2 spike glycoprotein-derived peptidome presented by HLA class II on dendritic cells. Cell Rep. 2021 May 25;35(8):109179. doi: 10.1016/j.celrep.2021.109179.[4]Knierman MD, Lannan MB, Spindler LJ et al. The Human Leukocyte Antigen Class II Immunopeptidome of the SARS-CoV-2 Spike Glycoprotein. Cell Rep. 2020 Dec 1;33(9):108454. doi: 10.1016/j.celrep.2020.108454.Acknowledgements:NIL.Disclosure of InterestsNone Declared.

CLINICAL AND IMMUNOLOGICAL PROFILES OF PATIENTS WITH ANTI-SYNTHETASE SYNDROME: A RETROSPECTIVE COHORT STUDY FROM A TERTIARY CENTRE

BackgroundAnti-synthetase syndrome (ASS) is a rare auto-immune condition that combines autoantibodies and specifics clinical manifestations, including myositis, interstitial lung disease (ILD), polyarthritis, mechanic's hands, Raynaud's phenomenon, and unexplained fever. The hallmark of this syndrome is the presence of anti-aminoacyl-tRNA-synthetase (ARS) antibodies. Several anti-ARS antibodies have been described, anti-Jo1 being the most common, followed by anti-PL7, anti-PL12, anti-OJ, anti-EJ, anti-KS, anti-YRS, and anti-Zo. According to a recent epidemiological survey, the rising number of patients with autoimmune diseases, including idiopathic inflammatory myopathies (IIM) coincides with the COVID-19 pandemic.ObjectivesTo evaluate the clinical characteristics of ASS patients with different anti-ARS antibodies from a tertiary rheumatology center.MethodsWe conducted a retrospective, single-centered study on consecutive patients diagnosed with ASS from 1 January 2015 to 31 December 2022. Clinical and serologic data were obtained by medical records review from hospital database. Myositis-specific antibodies (MSA) and myositis-associated antibodies (MAA) were tested using commercial ELISA kits. We included all patients fulfilling Connor's criteria for ASS.ResultsSixty-one patients (44 females) with mean age 54.4 (13.8) years were included. The most frequently reported clinical manifestation was arthralgia (68.8%), followed by Raynaud's phenomenon (67.2%), ILD (65.6%), myositis (46%), mechanic's hands (44.3%), arthritis (39.3%), and fever (18.0%). The typical triad for ASS, including myositis, arthritis and ILD was present in 17 patients. Twenty-eight (45.9%) patients were PL7+, 21 (34.4%) were Jo1+, 3 (4.9%) were PL12+, and 2 (3.2%) were OJ+. Seven patients were positive for more than two anti-ARS antibodies. The most frequently found MAA was anti-Ro52 (n=23, 37.7%). Of the 61 patients included, 41 (67.2%) patients were diagnosed in the last 3 years (COVID-19 pandemic). The most frequently detected MSA in ASS patients diagnosed during COVID-19 pandemic was anti-PL7 (25/28), while anti-Jo1 was the most common MSA in ASS patients diagnosed before 2020 (p<0.05) (Fig 1).The anti-Jo1+ patients were younger, have significantly more frequent muscle involvement and significantly higher levels of CK than anti-PL7+ patients (p<0.05). The co-occurance of anti-Ro52 antibodies was more frequently observed in anti-Jo1+ patients (n=11, 52.4%) than in anti-PL7+ patients (n=6, 21.4%) (p<0.05). We did not find statistically significant differences between ASS groups regarding sex, disease duration, clinical manifestations including dermatologic lesions, Raynaud's phenomenon, arthralgia/arthritis, ILD, fever, and cancers (all p>0.05).ConclusionASS patients have heterogenous manifestations, and different types of anti-ARS antibodies are associated to distinct clinical and immunological features. The COVID-19 pandemic led to increase prevalence of ASS cases and to a remarkable shift in the anti-ARS antibodies profile, with increased frequency of anti-PL7 antibodies. Further studies are needed to investigate the link between SARS-CoV-2 infections and myositis.References[1]Witt LJ, et al. The Diagnosis and Treatment of Antisynthetase Syndrome. Clin Pulm Med. 2016 Sep;23(5):218-226.[2]Gracia-Ramos AE, et al. New Onset of Autoimmune Diseases Following COVID-19 Diagnosis. Cells. 2021 Dec 20;10(12):3592.[3]Connors GR, et al. Interstitial lung disease associated with the idiopathic inflammatory myopathies: what progress has been made in the past 35 years? Chest. 2010 Dec;138(6):1464-74.[4]García-Bravo Let al. Association of anti-SARS-COV-2 vaccine with increased incidence of myositis-related anti-RNA-synthetases auto-antibodies. J Transl Autoimmun. 2022 Jun 30;5:100160.Figure 1.ASS patients with positive anti-ARS antibodies per year (from 2015 to 2022). The green line shows the PL7+ patients;and the orange line shows the Jo1+ cases.[Figure omitted. See PDF]AcknowledgementsI have no acknowledgements to declare.Disclosure of Inter stsNone Declared.

Susceptibility of domestic and wild animal species to SARS CoV-2 naturally infection (review)

Severe acute respiratory syndrome coronavirus (SARS-CoV-2), the causative agent of the current COVID-19 pandemic, has evolved to have a wide range of hosts, including non-human primates, wild and domestic animals. Determining the susceptibility of different animal species to SARS-CoV-2 infection and the role of animals in the epidemiology of the disease will be critical to designing appropriate human and veterinary public health responses to this pandemic. A better understanding of the susceptibility of animal species to SARS-CoV-2 may help clarify transmission mechanisms and identify potential reservoirs and sources of infection that are important for both animal and human health. The current pandemic produced by SARS CoV-2 and its variants represents an example of the unique concept of health (One Health) in which humans and animals are components of the same epidemiological chain. In this paper, only the natural infections found in different animals species will be reviewed, according to literature data, regarding the species of affected animals, the transmission patterns (human-animal, animal-human), clinical aspects, diagnosis confirmation and a brief presentation of the prevention possibilities through vaccination.

COVID-19 and the ageing immune system in an elderly patient: a case report

Background: The severity of COVID-19 infection has an increasing trend in the elderly, which contributes to the high morbidity and mortality rates in this population. Aging itself is a prominent risk factor for severe disease and death from COVID-19. Case Description: This case report a 71-year-old woman who complained of shortness of breath for 3 days before being admitted to the hospital. Bilateral consolidation and increased bronchovascular pattern were found on chest radiograph, and a positive SARS-COV2 nasopharyngeal swab PCR test result was noted. This patient was diagnosed with confirmed severe manifestation of COVID-19, community-acquired pneumonia and type 1 respiratory failure, as well as type II diabetes mellitus and suspicion of acute gastritis. The results of the geriatric status assessment were moderate functional status, risk of malnutrition, and moderate risk of deep vein thrombosis (DVT). This patient underwent treatment in accordance with the COVID-19 protocol along with management for geriatric status improvement. The patient was given permission to return home after 14 days of treatment, during which time her health had improved and her functional status had changed to moderate dependency. During follow-up, the patient continued to receive therapy. She is still being observed and future evaluations will be conducted. Conclusion: The increased susceptibility of the elderly to COVID-19 infection is caused by various factors. A burden of death and long-term disability brought on by this pandemic may be lessened by new or modified therapies that target aging-associated mechanisms. Therefore, COVID-19 case management in this population should be done with a comprehensive approach.

Establishment of a duplex fluorescent quantitative PCR assay for detection of Porcine circovirus type 2 and type 3

To establish a method for simultaneous detection of porcine circovirus type 2 (PCV2) and porcine circovirus type 3 (PCV3), specific primers and TaqMan probes were designed after sequence alignment according to the specific sequences of PCV2 Cap gene and PCV3 Cap gene on GenBank. By optimizing the reaction conditions, a duplex fluorescence quantitative PCR detection method for simultaneous detection of porcine circovirus type 2 and 3 was established, and the specificity, sensitivity, and reproducibility were tested. Specificity test results showed that in addition to the positive test results for PCV2 and PCV3, tests for PRRSV, CSFV, PPV, PRV, PEDV, and TGEV were all negative with no cross-reaction, indicating its good specificity. Sensitivity test results showed that the minimum detection limit for detection of PCV2 and PCV3 can both reach 10 copies.L-1, indicating its high sensitivity. The coefficient of variation within and between groups of this method was less than 2%, indicating its good stability. A total of 181 pork and whole blood samples collected from Zhejiang Province were tested using the detection method established in this article and the standard common fluorescent PCR detection method. The results showed that the positive rate of PCV2 was 50.83% (92/181), the positive rate of PCV3 was 37.57% (68/181), and the co-infection rate of PCV2 and PCV3 was 12.15% (22/181). The above detection results of ordinary fluorescent PCR were 50.28% (91/181), 36.46% (66/181), and the co-infection rate was 11.60% (21/181). The coincidence rates of the two methods for PCV2 and PCV3 can reach 98.91% and 97.06%, and the coincidence rate for PCV2 and PCV3 mixed infection were 95.45%. In summary, the duplex fluorescence quantitative PCR detection method established in this experiment can distinguish PCV2 and PCV3 rapidly, which can be used for pathogen detection and epidemiological investigation.

Effects of Porcine deltacoronavirus on the transduction pathway of the innate immune signal

Porcine deltacoronavirus (PDCOV) is a new type of pig intestinal coronavirus, which targets pig small intestinal epithelial cells to cause severe enteritis. After infecting the host, PDCoV finishes its proliferation in the host cell by antagonism or escape the innate immune signaling transduction pathway. In order to understand the action mechanism of PDCOV 0n the congenital immune signal transduction pathways, this paper reviews the effects of PDCOV on RLR, Jak-STAT, MAPK and mitochondrial signaling pathway to clarify the relationship between PDCOV and host innate immune signaling transduction pathways in order to provide help for the prevention and treatment of PDCOV infection.

Covid-19: Cases of inflammatory syndrome in children surge after urgent alert

Thirty fold increase In the province of Bergamo, Italy, researchers have reported a 30 fold increased incidence of Kawasaki like disease since the start of the covid-19 outbreak. Among the covid-19 group more children had cardiac symptoms (6 out of 10), Kawasaki disease shock syndrome (5 out of 10), macrophage activation syndrome (5 out of 10), and the need for adjunctive steroid treatment (8out of 10). In the pre-covid-19 group only two of 19 children had cardiac involvement and just three required adjunctive steroid treatment. A distinct syndrome Julia Kenny, a consultant in paediatric infectious diseases and immunology at Evelina London Children's Hospital, said that the Italian findings appear consistent with cases seen in the south east of England.

Did the Pandemic Impact the Brains of Our Science Students?

Ian Gotlib, lead author of the study stated, "We know that early adversity and stress can accelerate biological aging and brain maturation. [...]these students face a higher risk of memory and learning problems and may be why we are seeing skyrocketing cases of anxiety and depression among our students since the pandemic. The articles in this special issue provide ideas for teachers to upgrade their knowledge on immunology, gain ideas for infusing immunology into their teaching, and rethink applicability and language of the standards to include scientific phenomena that emerge daily but are not necessarily reflected within NGSS and state standards.

Effect of changes of vaccination strategies on IBV epidemiology, diagnosis and control: an Italian retrospective study

Infectious bronchitis virus (IBV) is among the most impactful poultry pathogens, whose control, based on biosecurity and routine vaccination, is hampered by the existence of countless genetic variants sharing poor cross-protection. A retrospective study was conducted on IBV positive samples collected in Italian broiler farms from 2012 to 2019. In 2015, the adopted vaccination protocol shifted from a Mass and 793B-based vaccines to the administration of Mass and QX vaccines, allowing to study how changes in vaccination strategies may affect IBV epidemiology, control and diagnosis in the field. The most frequently detected lineages were QX (70.3%), 793B (15.8%) and Mass (11.9%). The relative frequencies of QX and 793B detections remained stable throughout the study, while Mass detections significantly increased after the vaccination change. Rather than to an actual growth of Mass population size, this finding may be attributable to different vaccine interactions, with Mass strains being more frequently concealed by 793B vaccines than by QX ones. Based on the obtained results, the two vaccination protocols appear to be similarly effective in fighting IB outbreaks, which in the last decade have been caused primarily by QX field strains in Italy. These results indicate that vaccination strategies may significantly affect IBV epidemiology and diagnosis, and should therefore be considered when choosing and interpreting diagnostic assays and planning control measures.

Hacettepe health cohort (HU-CoVaCS): study design, baseline characteristics and the first 3-month-follow up of COVID-19 vaccinated students

Objective: This study included participants from Hacettepe University 4th, 5th, and 6th-grade students of Medical School and 4th and 5th-grade students of Dental School;and aimed to evaluate the general health status, COVID-19 history, vaccination status, and SARS-CoV-2 antibody levels of the participants to support their physical and social health, during the pandemic period. Methods: A prospective cohort study was conducted with an integrated, matched, nested case-control study. Sociodemographic characteristics, life habits, COVID-19 history, vaccination status, compliance with mask-distance-hygiene rules, and risks (if any) for COVID-19 were inquired via online questionnaires. Physical examinations, complete blood count, biochemistry tests, and anti-SARS-CoV-2 anti-spike antibody tests were conducted for all consenting participants. All analyses were established using depersonalized data. Results: Of the 778 participants completing the baseline visit in June-July 2021, the percentages of those vaccinated with at least one, two, and three/more doses of COVID-19 vaccine were 99.1%, 98.0%, and 11.7%, respectively;one had four doses. The median (minimum-maximum) time since the last vaccination was 134 (34-166) days for those vaccinated with two doses [CoronaVac (Sinovac Life Sciences, Beijing, China)] and 25 (14-56) days for those vaccinated with three doses [two doses of CoronaVac and a last dose of Pfizer-BioNTech mRNA vaccine (ComirnatyR). The third dose was applied at a median of 164 (151-202) days after the second dose, and all were heterologous in type. The median (minimum-maximum) antibody level for the overall group was 53.55(0-5680) BAU/mL: 47.19 BAU/mL in those who received two doses, with a more than 100 times increase after a third dose (4943.64 BAU/mL). Of the 522 participants followed up to October 1, 2021, 6 PCR-positive symptomatic participants were diagnosed with COVID-19: the incidence rate was 4/1000 person-months. Conclusion: A 100-fold neutralizing antibody level following the third dose demonstrated the importance of a booster dose. Given the time lag between doses, antibody measurements of BioNTech recipients should be repeated in the upcoming months. Booster selection should involve antibody level, variant sensitivity of the vaccine, and individual characteristics of the recipient.