scholarly journals Immunogenicity and efficacy of heterologous ChadOx1/BNT162b2 vaccination

Author(s):  
bruno pozzetto ◽  
vincent legros ◽  
Sophia Djebali ◽  
véronique barateau ◽  
nicolas guibert ◽  
...  

Abstract Following severe adverse reactions in patients vaccinated with the AstraZeneca ChadOx1 (Chad) vaccine, European health authorities have recommended that patients under the age of 55 who received one dose of Chad vaccine receive a second dose of Pfizer BNT162b2 (BNT) vaccine as a booster. However, the effectiveness and the immunogenicity of this vaccination regimen have not been formally tested. Here, we show that the heterologous Chad/BNT combination confers better protection against SARS-CoV-2 infection than the homologous BNT/BNT combination in a population of health care workers. To understand the underlying mechanism, we monitored in a longitudinal way the anti-spike immunity conferred by each vaccinal combination. Both combinations induced strong anti-spike antibody responses after boost in all vaccinated individuals. However, sera from heterologous vaccinated individuals displayed a stronger neutralizing activity, regardless of the SARS-CoV-2 variant analyzed, and this was associated with more switched memory RBD-specific B cells with an activated phenotype and less IgA. The Chad vaccine induced a stronger T cell response than the BNT vaccine after the priming dose, and the reciprocal was true for the IgG response, which could explain the complementarity of both vaccines when used in an heterologous setting. This strongly protective vaccination regimen could be therefore particularly suitable for immunocompromised individuals.

Author(s):  
Mukul Patar ◽  
Kusum Borsaikia ◽  
Taufeequl Islam

<p class="abstract">Otolaryngologists are more prone for exposure to aerosols during routine ENT examination and endoscopic procedures. ENT endoscopy procedures are considered as most aerosol-generating procedures and preferably routine procedures are avoided and deferred, if at all not necessary or urgent at this time of COVID-19 pandemic. The small particle size and extended travel of airborne aerosols mandate the use of specific personal protective equipment (PPE) and barriers by the health care workers to protect against transmission of COVID-19. Studies have recommended ENT endoscopy in awake patients with adequate topical preparation for local anaesthesia. Use of sprays should be avoided, instead, carefully placed pledgets should be used to provide adequate decongestion and anesthesia. Well ventilated endoscopy room with negative pressure (preferably), wearing a N95 mask with face shield or full PPE, thorough cleaning of entire endoscope after removal by standard disinfectants, decontamination of endoscopy room after each procedure and proper disposal of contaminated waste products are some common guidelines advised by health authorities globally till date.</p>


2021 ◽  
Vol 11 (6) ◽  
pp. 576
Author(s):  
Elissavet Kontou ◽  
Kyriaki Ranellou ◽  
Dimitrios Zoulas ◽  
Anastasia Bletsa ◽  
Eirini Rompola ◽  
...  

We analyzed the antibody responses of 564 hospital workers in Athens, Greece, after vaccination with two doses of the BNT162b2 (Comirnaty®; BioNTech and Pfizer) mRNA COVID-19 vaccine. A greater antibody increase was observed in women, younger age groups, previously infected individuals and personnel working in COVID-19 clinics. Notably, individuals with a prior COVID-19 infection mounted a significantly higher antibody titer following the first dose than the rest of the population; the same was true for those working in COVID-19 clinics, even without history of previous infection.


2005 ◽  
Vol 49 (10) ◽  
pp. 4404-4405 ◽  
Author(s):  
M. Graham ◽  
R. Nixon ◽  
L. J. Burrell ◽  
C. Bolger ◽  
P. D. R. Johnson ◽  
...  

ABSTRACT We assessed cutaneous adverse reactions (CARs) to alcohol-based hand rub (ABHR) after the introduction of a hand hygiene culture change program at our institution. CARs were infrequent among exposed health care workers (HCWs) (13/2,750; 0.47%; 1 CAR per 72 years of HCW exposure) and were not influenced by the duration or intensity of ABHR use but were associated with the presence of irritant contact dermatitis.


Author(s):  
Seri Jeong ◽  
Nuri Lee ◽  
Su Kyung Lee ◽  
Eun-Jung Cho ◽  
Jungwon Hyun ◽  
...  

Reliable results of serologic positivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody before and after AstraZeneca (AZ) vaccination are essential to estimate the efficacy of vaccination. We assessed the positivity rates and associated factors using five SARS-CoV-2 antibody assays. A total of 228 paired serum samples (456 samples) were obtained from 228 participants. After baseline sampling, the second sampling was conducted between 11-28 days after the first dose of AZ. Sera were tested using five SARS-CoV-2 antibody assays, including two surrogate virus neutralization tests. A questionnaire on symptom, severity, and duration of adverse reactions was completed by all participants. The overall positive rates for SARS-CoV-2 antibody were 84.6% for Roche, 92.5% for Abbott, 75.4% for Siemens, 90.7% for SD Biosensor, and 66.2% for GenScript assays after the first dose of AZ vaccination. The positive rates and antibody titer of sera obtained between 21-28 days were significantly higher than those obtained between 11-20 days in all five assays. More severe and longer duration of adverse reactions were related to higher SARS-CoV-2 antibody levels. The agreements and correlations among the applied assays were substantial (к=0.73-0.95) and strong (ρ=0.83-0.91). A single dose of AZ vaccination led to high positivity rates based on the five assays. Days after vaccination and adverse reactions could help estimate serologic conversions. The results should be interpreted cautiously considering the applied assays and cutoffs. Our findings could inform decisions regarding vaccination and laboratory settings and, thus, contribute to the control of the spread of SARS-CoV-2 infection.


Author(s):  
Seri Jeong ◽  
Nuri Lee ◽  
Su Kyung Lee ◽  
Eun-Jung Cho ◽  
Jungwon Hyun ◽  
...  

Reliable results for serologic positivity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody after the second dose of AstraZeneca (AZ) vaccination are important to estimate the real efficacy of vaccination. We evaluated the positivity rates and the changes of semi-quantitative antibody titers before and after the first and second ChAdOx1 nCoV-19 Vaccinations using five SARS-CoV-2 antibody assays, including two surrogate virus neutralization tests. A total of 674 serum samples were obtained from 228 participants during three blood sampling periods. A questionnaire on symptoms, severity and adverse reactions duration was completed after the second vaccination. The overall positive rates for all assays were 0.0-0.9% before vaccination, 66.2-92.5% after the first vaccination, and 98.2-100.0% after the second vaccination. Median antibody titers in five assays after the second dose of vaccination were increased compared to those after the first dose (106.4-fold increase for Roche total antibody, 3.6-fold for Abbott IgG, 3.6-fold for Siemens, 1.2-fold for SD Biosensor V1 neutralizing antibody, and 2.2-fold for GenScript neutralizing antibody). Adverse reactions reduced after the second dose in 89.9% of participants compared to after the first dose. Overall, the second vaccination led to almost 100% positivity rates based on these SARS-CoV-2 antibody assays. The results should be interpreted with caution, considering the characteristics of applied assays. Our findings could inform decisions regarding vaccination and the use of immunoassays, thus, contributing to the SARS-CoV-2 pandemic control.


10.2196/23441 ◽  
2021 ◽  
Vol 23 (2) ◽  
pp. e23441
Author(s):  
Alberto M Borobia ◽  
Irene García-García ◽  
Lucía Díaz-García ◽  
Amelia Rodríguez-Mariblanca ◽  
Lucía Martínez de Soto ◽  
...  

Background In April 2020, two independent clinical trials to assess SARS-CoV-2 prophylaxis strategies among health care workers were initiated at our hospital: MeCOVID (melatonin vs placebo) and EPICOS (tenofovir disoproxil/emtricitabine vs hydroxychloroquine vs combination therapy vs placebo). Objective This study aimed to evaluate the reasons why health care workers chose to participate in the MeCOVID and EPICOS trials, as well as why they chose one over the other. Methods Both trials were offered to health care workers through an internal news bulletin. After an initial screening visit, all subjects were asked to respond to a web-based survey. Results In the first month, 206 health care workers were screened and 160 were randomized. The survey participation was high at 73.3%. Health care workers cited “to contribute to scientific knowledge” (n=80, 53.0%), followed by “to avoid SARS-CoV-2 infection” (n=33, 21.9%) and “the interest to be tested for SARS-CoV-2” (n=28, 18.5%), as their primary reasons to participate in the trials. We observed significant differences in the expected personal benefits across physicians and nurses (P=.01). The vast majority of volunteers (n=202, 98.0%) selected the MeCOVID trial, their primary reason being their concern regarding adverse reactions to treatments in the EPICOS trial (n=102, 69.4%). Conclusions Health care workers’ reasons to participate in prophylaxis trials in an acute pandemic context appear to be driven largely by their desire to contribute to science and to gain health benefits. Safety outweighed efficacy when choosing between the two clinical trials.


2021 ◽  
Author(s):  
Mónica Martínez-Gallo ◽  
Juliana Esperalba-Esquerra ◽  
Ricardo Pujol-Borrell ◽  
Victor Sandá ◽  
Iria Arrese-Muñoz ◽  
...  

AbstractBackgroundClinical trials on the different vaccines to SARS-CoV-2 have demonstrated protection efficacy, but it is urgent to assess the levels of protection generated with real-world data, especially in individuals professionally exposed. Measuring T-cell responses may complement antibody tests currently in use as correlates of protection but there are not validated T cell response applicable to large number of samples.ObjectiveTo assess the feasibility of using T-cell responses to SARS-CoV-2 S peptides by commercially available whole blood interferon-gamma release assays (IGRA) as a correlate of protection.PatientsTwenty health care workers before and after vaccination.MethodsAntibody test to SARS-CoV-2 N and S proteins in parallel with one IGRA assay and two detection techniques than can be automated.ResultsIGRA test detected T-cell responses in naturally exposed and vaccinated HCW already after first vaccination dose. the correlation by the two detection methods, CLIA and ELISA, very high (R>0.9) and sensitivity and specificity ranged between 100 and 86% and 100-73% respectively. Even though there was a very high concordance between antibody and the IGRA assay in the ability to detect immune response to SARS-CoV-2 there was a relatively low quantitative correlation. In the small group primed by natural infection, one vaccine dose was sufficient to reach immune response plateau. IGRA was positive in one Ig (S) antibody negative vaccinated immunosuppressed HCW illustrating another advantage of the IGRA test.ConclusionWhole blood IGRA tests amenable to automation, as the one here reported, constitute a promising additional tool for measuring the state of the immune response to SARS-CoV-2; they are applicable to large number of samples and may become valuable correlates of protection to COVID-19, particularly for vulnerable groups at risk of being re-exposed to infection, as are health care workers.Clinical ImplicationsCommercial kits of whole blood Interferon-gamma release assay (IGRA) constitute an reliable method for clinical laboratories to assess T-cell response after natural infection by SARS-CoV-2 and after BNT162b2 mRNA vaccination and are suitable for large scale application.Key MessagesCommercial kits of whole blood interferon-gamma release assay (IGRA) are potentially very useful tools to measure the T cell response to SARS-CoV-2 after COVID-19 and after SARS-CoV-2 vaccination.One vaccine dose restores T cell response in COVID recovered patients, but the vaccination boost was required for naïve participants to attain a comparable response.T cell response seem to decay in COVID recovered subjects after the boost second vaccination dose.Capsule SummaryMeasuring T cell responses by commercially available whole blood interferon gamma release assays (IGRA) provide a promising additional correlate of protection to COVID and may be useful to reassure vulnerable group professionals at risk of being exposed to SARS-CoV-2 infection.


2021 ◽  
Vol 9 (6) ◽  
pp. 1315
Author(s):  
Chiara Agrati ◽  
Concetta Castilletti ◽  
Delia Goletti ◽  
Silvia Meschi ◽  
Alessandra Sacchi ◽  
...  

Vaccination is the main public health measure to reduce SARS-CoV-2 transmission and hospitalization, and a massive worldwide scientific effort resulted in the rapid development of effective vaccines. This work aimed to define the dynamics of humoral and cell-mediated immune response in a cohort of health care workers (HCWs) who received a two-dose BNT162b2-mRNA vaccination. The serological response was evaluated by quantifying the anti-RBD and neutralizing antibodies. The cell-mediated response was performed by a whole blood test quantifying Th1 cytokines (IFN-γ, TNF-α, IL-2), produced in response to spike peptides. The BNT162b2-mRNA vaccine induced both humoral and cell-mediated immune responses against spike peptides in virtually all HCWs without previous SARS-CoV-2 infection, with a moderate inverse relation with age in the anti-RBD response. Spike-specific T cells produced several Th1 cytokines (IFN-γ, TNF-α, and IL-2), which correlated with the specific-serological response. Overall, our study describes the ability of the BNT162b2 mRNA vaccine to elicit a coordinated neutralizing humoral and spike-specific T cell response in HCWs. Assessing the dynamics of these parameters by an easy immune monitoring protocol can allow for the evaluation of the persistence of the vaccine response in order to define the optimal vaccination strategy.


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