Response In Healthcare Workers Research Articles

Application of Oxidative Stress Parameters and Alkaline Comet Assay for Monitoring DNA Degradation Response in Healthcare Workers Exposed to Chronic Ionizing Radiation at Banha University Hospitals

Application of Oxidative Stress Parameters and Alkaline Comet Assay for Monitoring DNA Degradation Response in Healthcare Workers Exposed to Chronic Ionizing Radiation at Banha University Hospitals

Interaction, Management and Response of Healthcare Workers Towards Workplace Violence Events

Objective: To evaluate the interaction, management and response towards WPV events by HCW’s of emergency department Methodology: We conducted this cross-sectional study using World Health Organization’s tool to collect quantitative data on workplace violence (WPV) amongst universally sampled 164 health professionals working in an emergency department at Nishtar hospital Multan from June-August 2019 after taking an inform consent. All physically present health professionals who have been working there including paramedics, doctors, & nurses, were part of research. Results: Out of 164 healthcare employees, males were ninety-seven while females were sixty-seven. All the subjects said that they work in shifts, anytime between 18h00 (6 PM) and 07h00 (7 AM), and interact with patients/clients during work as well. Only 11% reported that they have routinely direct physical contact (washing, turning, lifting) with patients/clients. When talking about response to the incident, approximately one-third of the participants sought help from association, almost half of the HCW’s reported to their senior staff, 13.5% subject sought help from union, merely 3.5% HCW told the person to stop whereas, 4.5% told family/friends Conclusion: Health professionals working in shifts, and also interacting with patients/clients faced violence and mostly reported to their senior staff, or sought help from their association.

The Prospective COVID-19 Post-Immunization Serological Cohort in Munich (KoCo-Impf): Risk Factors and Determinants of Immune Response in Healthcare Workers.

Antibody studies analyze immune responses to SARS-CoV-2 vaccination and infection, which is crucial for selecting vaccination strategies. In the KoCo-Impf study, conducted between 16 June and 16 December 2021, 6088 participants aged 18 and above from Munich were recruited to monitor antibodies, particularly in healthcare workers (HCWs) at higher risk of infection. Roche Elecsys® Anti-SARS-CoV-2 assays on dried blood spots were used to detect prior infections (anti-Nucleocapsid antibodies) and to indicate combinations of vaccinations/infections (anti-Spike antibodies). The anti-Spike seroprevalence was 94.7%, whereas, for anti-Nucleocapsid, it was only 6.9%. HCW status and contact with SARS-CoV-2-positive individuals were identified as infection risk factors, while vaccination and current smoking were associated with reduced risk. Older age correlated with higher anti-Nucleocapsid antibody levels, while vaccination and current smoking decreased the response. Vaccination alone or combined with infection led to higher anti-Spike antibody levels. Increasing time since the second vaccination, advancing age, and current smoking reduced the anti-Spike response. The cumulative number of cases in Munich affected the anti-Spike response over time but had no impact on anti-Nucleocapsid antibody development/seropositivity. Due to the significantly higher infection risk faced by HCWs and the limited number of significant risk factors, it is suggested that all HCWs require protection regardless of individual traits.

Author response to: Letter to Editor in Response to Assessment of early and post COVID-19 vaccination antibody response in healthcare workers: a multicentre cross-sectional study on inactivated, mRNA and vector-based vaccines.

Author response to: Letter to Editor in Response to Assessment of early and post COVID-19 vaccination antibody response in healthcare workers: a multicentre cross-sectional study on inactivated, mRNA and vector-based vaccines.

Comparison of three dosing intervals for the primary vaccination of the SARS-CoV-2 mRNA Vaccine (BNT162b2) on magnitude, neutralization capacity and durability of the humoral immune response in health care workers: A prospective cohort study.

The dosing interval of a primary vaccination series can significantly impact on vaccine immunogenicity and efficacy. The current study compared 3 dosing intervals for the primary vaccination series of the BNT162b2 mRNA COVID-19 vaccine, on humoral immune response and durability against SARS-CoV-2 ancestral and Beta variants up to 9 months post immunization. Three groups of age- and sex-matched healthcare workers (HCW) who received 2 primary doses of BNT162b2 separated by 35-days, 35-42 days or >42-days were enrolled. Vaccine induced antibody titers at 3 weeks, 3 and 6-9 months post-second dose were assessed. There were 309 age- and sex-matched HCW (mean age 43 [sd 13], 58% females) enrolled. Anti-SARS-CoV-2 binding (IgG, IgM, IgA) and neutralizing antibody titers showed significant waning in levels beyond 35 days post first dose. The second dose induced a significant rise in antibody titers, which peaked at 3 weeks and then declined at variable rates across groups. The magnitude, consistency and durability of response was greater for anti-Spike than anti-RBD antibodies; and for IgG than IgA or IgM. Compared to the shorter schedules, a longer interval of >42 days offered the highest binding and neutralizing antibody titers against SARS-CoV-2 ancestral and Beta (B1.351) variants beyond 3 months post-vaccination. This is the first comprehensive study to compare 3 dosing intervals for the primary vaccination of BNT162b2 mRNA COVID-19 vaccine implemented in the real world. These findings suggest that delaying the second dose beyond 42 days can potentiate and prolong the humoral response against ancestral and Beta variants of SARS-CoV-2 up to 9 months post-vaccination.

Homologous booster immunization with an inactivated vaccine induced robust antibody response in healthcare workers: A retrospective study.

Coronavirus Disease 2019 (Covid-19) severely impacted the health, society, and economy around the world. With declining protective efficacy of primary vaccination and the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, a Covid-19 booster vaccination is being fully implemented globally. Many people received three doses of BBIBP-CorV inactivated vaccine in China and other developing countries. However, the antibody response and immune persistence of the homologous BBIBP-CorV booster vaccination is yet to be thoroughly evaluated, as previous studies focused within one month after the third dose. In this study, 97 participants were enrolled to analyze the antibody response and immune persistence within 6 months as well as the safety within 7 days after the third-dose of homologous BBIBP-CorV inactivated vaccine. The seroconversion rate for total antibody against the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein were both 100% at month 1 and month 6 after the third dose. The IgG against the RBD of the SARS-CoV-2 S protein seroconversion rate increased from 42.27% before the third dose to 100% 1 month after the third dose and then slightly decreased to 98.97% 5 months later. Positive IgM against the RBD of the SARS-CoV-2 S protein was rare and was observed in only one participant at month 1 after the third dose. The neutralizing antibody levels at month 1 and month 6 after the third dose increased 63.32-fold and 13.16-fold compared with those before the third dose, and the positive rate for neutralizing antibody was still 100% at month 6 after the third dose. Importantly, the antibody responses induced by the vaccine and immune persistence were not affected by sex or age. No serious adverse reactions were reported. Total antibody and IgG against the RBD of the SARS-CoV-2 S protein were highly correlated with neutralizing antibody, suggesting that total antibody and IgG against the RBD of the SARS-CoV-2 S protein could be used as predictors for neutralizing antibody. In conclusion, the third dose of homologous BBIBP-CorV inactivated vaccine induced a robust antibody response and moderate immune persistence. These finding are of great significance for development future vaccination strategies.

Corona virus pandemic response among health workers in selected health facilities in Meru county


 Abstract:
 
 Aims: The study aimed at determining the Level of knowledge, Preparedness and Response to Corona Virus Pandemic Outbreak among Health Care Workers in Meru County, Kenya.
 Study design: A cross-sectional study was adopted to conduct and determine Preparedness, Knowledge and Response of Health Care Workers (HCWs) to COVID-19 pandemic outbreak.
 Place and Duration of Study: Sample: Meru County, Igembe South Sub County Health Care Facilities between month of March and June 2020.
 Methodology: A cross-sectional study was conducted among HCWs to determine their Preparedness, Knowledge and Response to COVID - 19 Pandemic outbreak. The study population constituted of health care workers working in Igembe south in Meru County.
 Results: About 87 health care workers of mean age 34± 9 (SD) years with a minimum age of 19 years and maximum age of 70 years were recruited to take part in the study. Among the participants recruited in the study, 51 (58.6%) had bachelor's degree, 30 (34.5%) participants had an ordinary diploma and 6 (6.9%) participants had a certificate level of professional qualification. Most 32 (36.8%) the participants were nurses. Other professional disciplines interviewed were Doctors, Clinicians, Nutritionists, Health Records Officers, Support staff, Social Workers among others. Significant number managers of the Health Care Facilities acknowledged receiving Ministry of Health Guidelines and Protocols on COVID-19 case management. Most (60; 69%) of the participants strongly disagreed that HCWs were trained on Case definition and management of Corona Virus Infections according to WHO guidelines i.e. Nurses (71; 81.6%), Clinical officers (62; 71.3%), Non-Core Health Care Workers (72; 82.8%) were well prepared, trained to handle cases of corona virus infections and associated emergencies. Response to COVID – 19 pandemic indicates that a significant number of (75; 86.2%) of participants strongly disagreed that Health Facilities were equipped with laboratories to test COVID -19, (70; 80.5%) of the participants strongly disagreed that PPEs were available and (70; 80.5%) of the participants strongly disagreed that Isolation and Consultation Rooms with dedicated clinicians are available. Overall a high proportion (73.6%) of the study participants strongly disagreed that they is good response to Corona Virus Pandemic out break interventions. 
 Conclusion: Knowledge, Preparedness and Response levels to COVID -19 pandemic infection outbreak was at an average and there is need for continuous professional development (CPD) for HCWs to ensure adoption, maintenance of newly acquired appropriate practices during the COVID-19 pandemic to enhance preparedness and Response to the current and future outbreaks. This creates requisite capacity and skills among Health Care Professionals in their respective areas of practice considering that inadequate knowledge, preparedness and disjointed response which is not only an occupational hazard but a risk factor for poor delivery but also an occupational risk to the workers.
 Keywords: COVID -19, Corona Virus, Health Care Workers, Preparedness, Knowledge, Pandemic, Facilities, Response.

Hepatitis B vaccination coverage and serological status among health care workers exposed to occupational biological hazards.

Health care workers are often exposed to hepatitis B infection during the course of their professional roles. To analyze the hepatitis B vaccination coverage and the presence of antibodies against hepatitis B among health care professionals who were exposed to contaminated biological material at a hospital complex. This descriptive, retrospective, and quantitative study is based on the analysis of accident notification form data (n = 2,466) from a hospital complex covering the period between 2011 and 2020. Among the affected individuals, women (69.5%), medical residents (35.7%), and nursing staff (25.5%) accounted for the highest proportion of hazards. Regarding vaccination status, 98% of the health care professionals reported being fully immunized, and antibodies were detected in 90.9% of the participants. Percutaneous exposure (76.4%) was the most prevalent type of hazard, with blood being the most commonly involved material (79.4%). The findings show that despite the risks of Hepatitis B contamination associated with the incidents, the professionals were protected due to the high vaccination coverage and evidence of immunity.

Durability of ChAdOx1 nCoV-19 (Covishield®) Vaccine Induced Antibody Response in Health Care Workers.

(i) Background: ChAdOx1 nCoV-19 (Covishield®) vaccine is widely used in India. We studied the Covishield® induced antibody response and its durability among health care workers (HCWs) (ii) Method: HCWs received two doses (0.5 mL) four weeks apart. Blood specimens, collected before each dose, day (D)60, D150 and D270 after second dose, were tested for anti-spike antibody (ASAb) titre and neutralising antibody (%) (NAb) using Elecsys Anti-SARS-CoV-2 S (Roche) and SARS-CoV-2 NAb ELISA Kit (Invitrogen), respectively. Data are expressed as proportions and median (interquartile range) and compared using non-parametric (iii) Result: Among 135 HCWs (83 males; age 45 (37-53); 36 had pre-existing ASAb), 29 (21.5%) acquired COVID-19 after 60 (39-68) days of vaccination. ASAb titre before second dose and at D60, D150, D270 were 77.2 (19.4-329.4), 512 (114.5-9212), 149 (51.6-2283) and 2079 (433.9-8644) U/mL, respectively. Compared to those without pre-existing ASAb, titres were significantly higher before second dose (5929 vs. 41, p < 0.001), D60 (3395 vs. 234, p = 0.007) and D150 (1805 vs. 103, p < 0.001) in participants with pre-existing ASAb; NAb were also higher (80 vs. 18, p < 0.001) before second dose. Between those who acquired infection or not after vaccination, ASAb titres were comparable before second dose (77 vs. 78, p = 0.362) but significantly higher at D60 (14,019 vs. 317, p < 0.001) and D150 (2062 vs. 121, p = 0.002) in the former group, though NAb percentage were higher at D60 (87 vs. 27, p < 0.001) and D150 (79 vs. 25, p = 0.007) only (iv) Conclusions: Covishield® induces a higher antibody titre in those with pre-existing ASAb. The vaccine induced antibody starts falling 5 months after vaccination.

Determinants of the Level of Anti-SARS-CoV-2 IgG ANTibodiEs after Vaccination (DANTE-SIRIO 7) Study in a Large Cohort of Healthcare Workers.

The aim of this study was to determine anti-SARS-CoV-2 IgG concentrations and their major determinants in healthcare workers (HCWs) after full vaccination with the BNT162b2 vaccine. We recruited 847 individuals vaccinated with two doses of the BNT162b2 vaccine, who completed the questionnaire, and whose antibody concentrations were tested after 3 and 6 months after full vaccination. Anti-SARS-CoV-2 IgG levels were measured on the routinely employed Siemens Atellica system. The cutoff for positivity was ≥21.8 BAU/mL. Three and 6 months after vaccination, the majority of participants were seropositive. Median concentrations of anti-SARS-CoV-2 IgG significantly decreased from 1145 BAU/mL (IQR: 543-2095) to 225 BAU/mL (IQR: 100-510). Major positive determinants of antibody levels were fever after both doses of vaccine, prior-COVID-19 exposure, and muscle pain after the first dose. Lack of symptoms after the second dose and time since vaccination were significant negative determinants of anti-SARS-CoV-2 IgG concentrations. No other factors, including age and gender, or underlying comorbidities had a significant effect on antibody levels in HCWs. The anti-SARS-CoV-2 response after two doses of BNT162b2 vaccine was independently associated with prior-COVID-19 exposure, time since vaccination, and the occurrence of symptoms after either dose of vaccine. Easily reportable adverse reactions may facilitate the identification of immune response in HCWs.

COVID-19 vaccination: Immune response in healthcare workers—A study with review of literature

ABSTRACT Background: As the world has been going through a pandemic of coronavirus disease 2019 (COVID-19) for the past two years, a safe and effective vaccine was urgently needed. Vaccination against the disease was launched in India on January 16, 2021 with healthcare workers, frontline workers, and the elderly above 60 years being the first beneficiaries. Vaccines being used in India are Covishield and Covaxin. Materials and Methods: Fifteen healthcare workers (HCWs) who were vaccinated with Covishield or Covaxin were included in the study, and T cell, B cell and antibody response of the HCWs were analyzed. Blood samples collected from every subject were sent for antibody analysis, hematological workup for cell counts, and flow cytometry was performed for various subsets of lymphocytes. Hematological variables in naïve HCWs (who never had any natural infection) and recovered HCWs (those recovered from natural infection) were compared. Results: Antibody index among recovered HCWs was significantly higher than the naïve HCWs. All the leucocyte parameters showed a higher median value in the recovered group except total leucocyte count (TLC), T helper cell count (Th cell), T helper cell to T cytotoxic cell (Th cell: CTL) ratio and natural killer (NK) cell. But only Th: CTL ratio showed a statistically significant difference. Conclusion: This study shows that the antibody index among individuals who had both vaccination and COVID-19 infection is significantly higher than those who just had vaccination. T helper cell to T cytotoxic cell ratio is lowered in the recovered HCWs as compared to the naïve HCWs and this finding is statistically significant.

Monkeypox Knowledge and Confidence in Diagnosis and Management with Evaluation of Emerging Virus Infection Conspiracies among Health Professionals in Kuwait.

As the 2022 human monkeypox (HMPX) multi-country outbreak is spreading, the response of healthcare workers (HCWs) is central to mitigation efforts. The current study aimed to evaluate HMPX knowledge and confidence in diagnosis and management among HCWs in Kuwait. We used a self-administered questionnaire distributed in July–August 2022 through a snowball sampling approach. The survey items evaluated HMPX knowledge, confidence in diagnosis and management of the disease, and the belief in conspiracies regarding emerging virus infections (EVIs). The sample size was 896 HCWs: nurses (n = 485, 54.1%), pharmacists (n = 154, 17.2%), physicians (n = 108, 12.1%), medical technicians/allied health professionals (MT/AHP, n = 96, 10.7%), and dentists (n = 53, 5.9%). An overall low level of HMPX knowledge was noticed for items assessing virus transmission and non-cutaneous symptoms of the disease, with higher knowledge among physicians. Approximately one-fifth of the study sample agreed with the false notion that HMPX is exclusive to male homosexuals (n = 183, 20.4%), which was associated with lower knowledge with higher frequency among MT/AHP compared to nurses, physicians, and pharmacists. Confidence levels were low: confidence in diagnosis based on diagnostic tests (n = 449, 50.1%), confidence in the ability to manage the HMPX (n = 426, 47.5%), and confidence in the ability to diagnose HMPX clinically (n = 289, 32.3%). Higher confidence levels were found among nurses and participants with postgraduate degrees. Higher embrace of conspiracy beliefs regarding EVIs was noticed among participants with lower knowledge, and among those who agreed or were neutral/had no opinion regarding the false idea of HMPX exclusive occurrence among male homosexuals, while lower levels of belief in conspiracies were noticed among physicians, dentists, and pharmacists compared to MT/AHP. Variable levels of HMPX knowledge were observed in this study per item, with low level of knowledge regarding virus transmission. Differences in knowledge and confidence levels in diagnosis and management of HMPX should be considered in education and training aiming to prepare for outbreak response. The relatively high prevalence of embracing conspiratorial beliefs regarding EVIs is worrisome and needs proper interventions. The attitude towards male homosexuals’ role in monkeypox spread should be evaluated in future studies considering the possibility of stigma and discrimination in this most-at-risk group.

Psychological Responses of Health Care Workers Are Strongly Associated With Pandemic Management.

BackgroundGlobally, governments adopted protective measures to stabilize the worsening COVID-19 pandemic situation. These measures had a large impact on health care workers (HCWs) and could make the work environment more stressful for them. Therefore, we explored the associations of the psychological responses of HCWs and pandemic management among Slovak health care workers during the second wave of the pandemic.Materials and MethodsWe obtained data about psychological responses, COVID-19 experiences, information overload, non-adherence of the public, work stress and barriers and facilitators of health care provision from HCWs at the COVID-19-related departments of one hospital that mainly covered eastern Slovakia (215 health care professionals, 77.7% females, M/SD = 44.4). Data were analyzed using logistic regression models adjusted for gender.ResultsPandemic management was most strongly associated with psychological responses, such as irritability, sadness, anxiety, dizziness, and back pain, in health care workers. The non-adherence of the public had the strongest associated psychological impact on HCWs, mostly affecting anxiety and irritability (odds ratios, ORs varying from 3.9 to 7.0). From the barriers and facilitators of health care provision, the use of personal protective equipment had the most impact psychologically, whereas efficient department management was most protective, with ORs around 0.3.ConclusionPandemic management has a large impact on health care workers, and promoting resilience may seriously decrease job-related stress and associated psychological responses of HCWs.

Heterologous booster COVID-19 vaccination elicited potent immune responses in HCWs

The objective of our study was to evaluate the antibody responses of health care workers (HCWs) who were vaccinated with booster dose BNT162b2 6 months after 2 doses of the CoronoVac vaccine. The study included 318 HCWs vaccinated with inactive CoronaVac SARS-CoV-2 vaccine in 2 doses. Anti-spike/RBD IgG levels were measured immediately before and 1 month after the booster dose. In the sixth month after CoronaVac vaccination, the median of antibody levels of 1212.02 AU/ML, while it was 9283 AU/mL after BNT162b2 vaccination. IgG antibody titers of over 1050 AU/mL (which is equivalent to 1:80 dilution in the plaque reduction neutralization test) were detected in HCWs 15.09% and 97.8%, respectively. Our results showed that antibody titers increased 8-fold after the booster dose. We believe that the administration of the mRNA vaccine as a booster dose can provide more effective protection against COVID-19 infection, especially in individuals with risk factors.

Follow up of the Humoral Response in Healthcare Workers after the Administration of Two Dose of the Anti SARS-CoV-2 Vaccines-Effectiveness in Delta Variant Breakthrough Infections.

The implementation of vaccination among healthcare workers (HCWs) allowed the management of the pandemic in a manner that differed from that in the first waves. It has been demonstrated that the mRNA vaccines elicit good humoral responses but that there are still breakthrough infections. In summer 2021, a fifth wave emerged, despite the good coverage of HCWs in Spain. We aimed to study the SARS-CoV-2 IgG antibody levels as a marker to predict the possibility of Delta variant infections after vaccination after a seroepidemiological campaign. Of the 5000 participants, a total of 4902 (98.04%) showed a positive result in the serological anti-S test and only 98 (1.96%) were negative. Among the 4368 fully vaccinated participants, only in five cases was the serology negative. Of the total number of participants that received antibody results during the study, 162 were PCR positive in the subsequent two months. Among these, 151 were fully vaccinated (two doses). Significant differences between antibody BAU/mL levels were found between PCR positive and non-PCR positive participants (p < 0.01). The median of BAU/mL was higher in those vaccinated patients with no infection (1260 BAU/mL; 465–2080) versus infected patients (661 BAU/mL; 361–2080). These data support the idea that vaccines play an important role in the control of the pandemic, especially among HCWs at the time of the Delta variant circulation. More studies with other variants of concern must be performed in order to establish a correlation between the levels of IgG and the new infections.

Lasting SARS-CoV-2 specific IgG Antibody response in health care workers from Venezuela, 6 months after vaccination with Sputnik V

BackgroundScarce information is available regarding the long-term immunogenicity of the Sputnik V vaccine. Here Sputnik V vaccinated subjects were evaluated 6 months after receiving the 2-dose prime-boost schedule. MethodsEighty-six hospital workers from Venezuela, 32 with a previous COVID-19 infection and 54 SARS-CoV-2 naïve subjects, were enrolled. IgG antibodies levels against the wild-type Receptor Binding Domain (RBD) were measured in an ELISA and with an in vitro ACE2-surrogate RBD binding inhibition assay at day 42 and day 180 after receiving the second dose. IgG levels were expressed in BAU/ml. Binding inhibition antibodies were expressed in IU/ml. ResultsOn average, RBD-IgG levels decreased by approximately 50% between the two time-points in the COVID-19 naïve cohort (geometric mean concentration (GMC) 675 BAU/mL vs. 327 BAU/ml) and decreased by approximately 25% in the previously infected cohort (GMC 1209 BAU/mL vs 910 BAU/ml). Within our cohort, 94% showed a “good to excellent” neutralizing activity measured with the in vitro test 6 months after vaccination. ConclusionsThe Sputnik V vaccine provided long-term and durable humoral immunity in our cohort specially if a person has been both vaccinated and had a previous infection with SARS-CoV-2.

Evaluation of Humoral Response of Emergency Unit Healthcare Workers after Third Dose of COVID-19 Vaccination

Background: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is an emerging disease that has become pandemic. Healthcare workers are vulnerable persons due to SARS-CoV-2 infection. Healthcare workers are a government priority in the COVID-19 vaccine program. Antibody titer evaluation to healthcare workers as the first liner is essential due to the risk of the job. Purposes: The study aims to assess IgG antibody humoral response in healthcare workers in the emergency unit of Anton Soedjarwo Hospital, Pontianak, before and after the third dose of the COVID-19 vaccine. Methods: This study was a descriptive study with a cohort method. Twenty-two healthcare workers in the Emergency Unit in Anton Soedjarwo Hospital, Pontianak, participated in the study. Three ml venous blood samples were collected from the participants in two periods to quantify IgG antibody titer. The first period was before the third dose of the COVID-19 vaccine, and the second period was one month after the third dose of the COVID-19 vaccine. Chemiluminescent Microparticle Immunoassay (CMIA) methods were used to quantification IgG antibodies against spike-receptor binding domain (S-RBD) protein of SARS-CoV-2 Results: One month before the third dose of the COVID-19 vaccine, the majority of IgG antibodies show seropositivity (90.91%), with most on range 50-10,000 AU/ml (54.55%). Two participants (9.09%) show IgG antibodies less than 50 AU/ml (seronegative). One month after the third vaccination dose, all participants (100%) elicit IgG antibodies. Based on the comparison of IgG antibody titer before and after the third dose of the vaccine, the majority (68.18%) showed increasing the IgG antibody titer after the third vaccine. Conclusion: The third dose vaccine might effectively elevate immune response to SARS-CoV-2 infection.

Kinetics and Persistence of the Cellular and Humoral Immune Responses to BNT162b2 mRNA Vaccine in SARS-CoV-2-Naive and -Experienced Subjects: Impact of Booster Dose and Breakthrough Infections.

BackgroundUnderstanding and measuring the individual level of immune protection and its persistence at both humoral and cellular levels after SARS-CoV-2 vaccination is mandatory for the management of the vaccination booster campaign. Our prospective study was designed to assess the immunogenicity of the BNT162b2 mRNA vaccine in triggering the cellular and humoral immune response in healthcare workers up to 12 months after the initial vaccination, with one additional boosting dose between 6 and 12 months.MethodsThis prospective study enrolled 208 healthcare workers (HCWs) from the Liège University Hospital (CHU) of Liège in Belgium. Participants received two doses of BioNTech/Pfizer COVID-19 vaccine (BNT162b2) and a booster dose 6-12 months later. Fifty participants were SARS-CoV-2 experienced and 158 were naïve before the vaccination. Blood sampling was performed at the day of the first (T0) and second (T1) vaccine doses administration, then at 2 weeks (T2), 4 weeks (T3), 6 months (T4) and 12 months (T5) after the second dose. Between T4 and T5, participants also got the third boosting vaccine dose. A total of 1145 blood samples were collected. All samples were tested for the presence of anti-Spike antibodies, using the DiaSorin LIAISON SARS-CoV-2 Trimeric S IgG assay, and for anti-Nucleocapsid antibodies, using Elecsys anti-SARS-CoV-2 assay​​. Neutralizing antibodies against the SARS-CoV-2 Wuhan-like variant strain were quantified in all samples using a Vero E6 cell-based neutralization assay. Cell-mediated immune response was evaluated at T4 and T5 on 80 and 55 participants, respectively, by measuring the secretion of IFN-γ on peripheral blood lymphocytes using the QuantiFERON Human IFN-γ SARS-CoV-2, from Qiagen. We analyzed separately the naïve and experienced participants.FindingsWe found that anti-spike antibodies and neutralization capacity levels were significantly higher in SARS-CoV-2 experienced HCWs compared to naïve HCWs at all time points analyzed except the one after boosting dose. Cellular immune response was also higher in experienced HCWs six months following vaccination. Besides the impact of SARS-CoV-2 infection history on immune response to BNT162b2 mRNA vaccine, we observed a significant negative association between age and persistence of humoral response. The booster dose induced an increase in humoral and cellular immune responses, particularly in naive individuals. Breakthrough infections resulted in higher cellular and humoral responses after the booster dose.ConclusionsOur data strengthen previous findings demonstrating that immunization through vaccination combined with natural infection is better than 2 vaccine doses immunization or natural infection alone. The benefit of the booster dose was greater in naive individuals. It may have implications for personalizing mRNA vaccination regimens used to prevent severe COVID-19 and reduce the impact of the pandemic on the healthcare system. More specifically, it may help prioritizing vaccination, including for the deployment of booster doses.

Antibody Response in Healthcare Workers before and after the Third Dose of Anti-SARS-CoV-2 Vaccine: A Pilot Study.

The SARS-CoV-2 pandemic led to the development of various vaccines. The BNT162b2 mRNA vaccine was the first approved due to its efficacy in eliciting a humoral immunity response after the second dose. However, a decrease in the antibody concentration was observed over time. Therefore, the administration of a third dose was scheduled, primarily for frail people and workers of essential public activities. The aim of this study was to assess the level of antibodies against the spike (S) RBD of SARS-CoV-2 in healthcare workers before and after the third dose of BNT162b2 vaccine, according to sex, age, and the time interval between vaccine doses and tests. All 37 (12 males, 25 females, 19 < 50 years old, 18 ≥ 50 years old) healthcare workers recruited showed a consistent antibody titer increase after the third dose. Data analysis showed that the antibody concentration before the third dose significantly decreased as the time interval up to the test increased, and a significantly higher level was shown in young than older people. Cluster analysis revealed that young females had a higher antibody level than older females before the third dose (p < 0.05). This study indicated the benefit of the third dose of BNT162b2 vaccine and its effect on leveling up the humoral immune response.

Assessment of the humoral immunity induced by Sputnik V Covid-19 vaccine (GAM-COVID-VAC) in healthcare workers

BackgroundVaccination for COVID-19 in healthcare workers (HCW) is essential to protect one of the populations most exposed to this disease. However, data on the humoral response rate to the vaccine and the factors associated with it in this population are limited. Therefore, we aimed to evaluate the antibody response against SARS-CoV-2 in HCWs with complete Sputnik V vaccine scheme and factors associated with an increased antibody response. Material and methodsProspective study to evaluate the anti-SARS-CoV-2 humoral response in HCWs vaccinated with two doses of the Sputnik V vaccine (April-July 2021). The assessment of anti-Spike IgG antibodies in plasma was performed using the COVIDAR IgG enzyme-linked immunosorbent assay. A logistic regression was performed to identify independent factors associated with a positive IgG serology test and an elevated antibody response. ResultsA total of 630 HCWs were enrolled. Median age (IQR): 47 years (35-56). Female sex: 462 (73.33%). Previous COVID-19: 158 (25%). The median interval time between vaccine doses was 3 (3-4) weeks. Positive serology was observed in 607 (96.35%) HCWs. In the multivariate analysis, a history of systemic reactogenicity was identified as an independent variable associated with a positive serology; and history of systemic reactogenicity, COVID-19, interval between doses ≥4 weeks and time to serology <14 weeks were associated with an elevated antibody response. ConclusionsThis study provides data on the humoral response to the Sputnik V vaccine in a real-life setting. These initial data can contribute to the development of future immunization strategies in HCWs.