Adverse events following immunization associated with the ChAdOx1nCoV-19 and BBV152 vaccine-a cross-sectional study

COVID-19, an infectious disease, has become a leading cause of death in many people. The rapid emergence of the pandemic prompted the development of a vaccine to mitigate the disease's harmful consequences. Vaccination is the only effective way to prevent infection from spreading and build immunity to the virus. However, developing adverse effects has become a major problem for vaccine reluctance. Accordingly, the interest has been shifted towards identifying the adverse effects developed following immunization. The current study objective is to assess and compare the intensity of adverse effects following 1st and 2nd dose of COVID-19 vaccination and the medication administered to relieve the symptoms associated with vaccination. A cross-sectional study was performed in a community over six months. A total of 836 participants were involved in the study. All the data regarding the vaccination were collected through a specially designed questionnaire form and analyzed in all the participants within the study group. According to the study, at least 1 AEFI was developed in about 90% of the study population. The most common systemic and local effect developed in the study population was fever (59.42%) and pain at the injection site (69.82%), respectively. With both vaccines (ChAdOx1 nCoV-19 and BBV152), the incidence and severity of AEFIs were lower after the second dose than after the first dose, and most of the symptoms associated with vaccination were alleviated by taking home remedies and symptomatic treatment. The adverse effects reported after receiving the ChAdOx1 nCoV-19 and BBV152 vaccines are typical of most vaccines, and the majority of them were tolerated, and most subsided in less than 24 hours.

Investigation on anti-Corona viral potential of Yarrow tea.

Achillea millefolium (Yarrow) is a herbaceous plant of Greek origin noted to treat pneumonia, common cold, cough, and other respiratory disorders. The flowers and leaves are the core part used to prepare herbal tea that gains the world's recognition as medicinal tea. Coronavirus disease is spreading across the globe, and numerous approaches are lodged to treat virus-induced lung inflammation. Here, we used the network pharmacology, metabolite analysis, docking and molecular simulation and MM-PBSA analysis to comprehend the biochemical basis of the health-boosting impact of Yarrow tea. Next, we performed the microscopic and dynamic light scattering (DLS) analysis of yarrow-treated ChAdOx1 nCoV-19 to evaluate the virucidal activity of the Yarrow. The present study investigates the druggability, metabolites and potential interaction of the title tea with genes associated with Covid-19-induced pathogenesis. Towards this, 1022 gene hits were obtained, 30 are mutually shared. Network Pharmacology and microarray gene expression analysis find the connection of PTGS2 in relieving the virus-induced inflammation. Yarrow constituents Luteolin may inhibit or down-regulate the Cyclooxygenase II (PTGS2), a plausible mechanism underlying the Yarrow's anti-inflammatory actions. Further, the Yarrow's virucidal activity was assessed towards Transmission Electron Microscopic (TEM). The Yarrow treated SARS-nCoV-2 cell exhibits the disintegration of the virus membrane. This work provides a scientific basis for further elucidating the mechanism underlying Achillea millefolium's antiviral and anti-inflammatory properties.

A case report of vaccine-induced immune thrombotic thrombocytopenia (VITT) with genetic analysis.

The emergence of the rare syndrome called vaccine-induced immune thrombocytopenia and thrombosis (VITT) after adenoviral vector vaccines, including ChAdOx1 nCov-19, raises concern about one's predisposing risk factors. Here we report the case of a 56-year-old white man who developed VITT leading to death within 9 days of symptom onset. He presented with superior sagittal sinus thrombosis, right frontal intraparenchymal hematoma, frontoparietal subarachnoid and massive ventricular hemorrhage, and right lower extremity arterial and venous thrombosis. His laboratory results showed elevated D-dimer, C-reactive protein, tissue factor, P-selectin (CD62p), and positive anti-platelet factor 4. The patient's plasma promoted higher CD62p expression in healthy donors' platelets than the controls. Genetic investigation on coagulation, thrombophilia, inflammation, and type I interferon-related genes was performed. From rare variants in European or African genomic databases, 68 single-nucleotide polymorphisms (SNPs) in one allele and 11 in two alleles from common SNPs were found in the patient genome. This report highlights the possible relationship between VITT and genetic variants. Additional investigations regarding the genetic predisposition of VITT are needed.

One year safety and immunogenicity of AZD1222 (ChAdOx1 nCoV-19): Final analysis of a randomized, placebo-controlled phase 1/2 trial in Japan.

BACKGROUND: Long duration trial data for two-dose COVID-19 vaccines primary series' are uncommon due to unblinding and additional doses. We report one-year follow-up results from a phase 1/2 trial of AZD1222 (ChAdOx1 nCoV-19) in Japan. METHODS: Adults (n = 256) seronegative for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) were stratified by age, 18-55 (n = 128), 56-69 (n = 86) and ≥70-year-old (n = 42), and randomized 3:1 to AZD1222 or placebo. Safety, immunogenicity, and exploratory efficacy data were collected until study Day 365. RESULTS: Safety was consistent with previous reports. In AZD1222 vaccinees, humoral responses against SARS-CoV-2 steadily declined over time. By Day 365, anti-SARS-CoV-2 spike-binding (spike) and receptor-binding domain (RBD) mean antibody titers remained above Day 15 levels and pseudovirus neutralizing antibodies were undetectable in many participants. CONCLUSIONS: AZD1222 is immunogenic and well tolerated in Japanese adults. Expected waning in anti-SARS-CoV-2 humoral responses was observed; spike and RBD antibody titers remained elevated. (ClinicalTrials.gov: NCT04568031).

Vogt-Koyanagi-Harada disease following ChAdOx1 nCoV-19 and mRNA-1273 vaccination.

Almost all vaccines have been reported to be associated with ocular inflammation, which has caused some concern regarding global mass COVID-19 vaccination efforts. Vogt-Koyanagi-Harada disease (VKHD) is a granulomatous inflammation caused by an autoimmune response against antigens in melanocytes, including those in the eyes. The mechanism by which COVID-19 vaccines are associated with VKHD is still unclear. Here, we report two cases of VKHD following COVID-19 vaccination. The first is a case of probable VKHD that presented with bilateral vision loss after administration of the adenovirus-vectored vaccine ChAdOx1 nCoV-19 (AstraZeneca). The condition improved after intravenous methylprednisolone 1g daily for 3days, followed by oral methotrexate and a slow taper of oral corticosteroids. The second case is a patient with an established diagnosis of well-controlled VKHD who developed a reactivation of the disease after receiving the mRNA-based vaccine (mRNA-1273, Moderna). VKHD is a potential ocular event that could follow COVID-19 vaccination. Awareness of this association is key to early detection and treatment to prevent loss of vision.

Aortic thrombosis and acute limb ischemia after ChAdOx1 nCov-19 (Oxford-AstraZeneca) vaccination: a case of vaccine-induced thrombocytopenia and thrombosis (VITT).

INTRODUCTION: Vaccine-induced thrombocytopenia and thrombosis (VITT) is a rare but devastating adverse event associated with the ChAdOx1 nCoV-19 (Oxford-AstraZeneca) adenoviral vaccine against the Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2). METHODS: A 49-year-old man presented to the emergency department with acute right limb ischemia (Rutherford IIB) nine days after his ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccination. CT angiography revealed significant aortic thrombosis and right femoral artery occlusion. Severe thrombocytopenia (platelet count of 23 × 103/µL), promptly elevated D-dimers (37937 ng/mL) and a reduced fibrinogen level (176 mg/dL) were remarkable. ELISA testing for anti-PF4 antibodies confirmed the diagnosis of VITT. RESULTS: An emergency revascularization of the right leg was provided via thrombectomy. High-dose intravenous immunoglobulins were administered whereafter the platelet count restored gradually. Therapeutic anticoagulation was progressively started. The postoperative course was uneventful and follow-up imaging after four weeks showed an almost complete resolution of the significant aortic thrombosis. CONCLUSION: Early recognition and appropriate counseling of VITT is advocated to pursue a good clinical outcome. Our patient presenting with severe aortic thrombosis and acute limb ischemia was successfully treated by a vascular thrombectomy along with intravenous immunoglobulins and anticoagulation therapy as the mainstay therapy.

Immunogenicity of the ChAdOx1 nCoV-19 vaccine in patients with hematologic malignancies.

Purpose: The present study aimed to study the immunogenicity of the ChAdOx1 nCoV-19 vaccine in patients with hematologic malignancies. Materials and Methods: This prospective cohort study of hematology patients aimed to evaluate their antibody levels against the receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein and seroconversion rates following two doses of the ChAdOx1 nCoV-19 vaccine. Between June and July 2021, we enrolled 61 patients and included 44 patients in our analysis. Antibody levels were assessed 8 and 4 weeks after the first and second injections, respectively, and compared with those of a healthy group. Results: Eight weeks after the first dose, the geometric mean antibody level was 1.02 binding antibody units (BAU)/mL in the patient group and 37.91 BAU/mL in the healthy volunteer group (p<0.01). Four weeks after the second dose, the geometric mean antibody level was 9.44 BAU/mL in patients and 641.6 BAU/mL in healthy volunteers (p<0.01). The seroconversion rates 8 weeks after the first dose were 27.27% and 98.86% in the patient and healthy volunteer groups, respectively (p<0.001). The seroconversion rate 4 weeks after the second dose was 47.73% in patients and 100% in healthy volunteers. Factors leading to lower seroconversion rates were rituximab therapy (p=0.002), steroid therapy (p<0.001), and ongoing chemotherapy (p=0.048). Factors that decreased antibody levels were hematologic cancer (p<0.001), ongoing chemotherapy (p=0.004), rituximab (p<0.001), steroid use (p<0.001), and absolute lymphocyte count <1,000/mm3 (p=0.009). Conclusion: Immune responses were impaired in individuals with hematologic malignancies, particularly patients undergoing ongoing therapy and B-cell-depleting therapy. Additional vaccinations should be considered for these patients, and further investigated.

Surveillance on Adverse Events Following COVISHIELD (ChAdOx1 nCoV-19) vaccination in Goa, India: An observational study.

BACKGROUND: COVISHIELD, ChAdOx1 nCoV- 19 Corona Virus Vaccine was granted emergency use authorization (EUA) as the first vaccine in India in January 2021. Knowing what to anticipate after vaccination will reduce vaccine hesitancy in the public. This study aimed to identify and measure the adverse events following COVID-19 vaccination. MATERIALS AND METHODS: A cross-sectional observational study was conducted at Goa Medical College, starting on February 21 till May 23, 2021. A total of 418 people were enrolled. We collected the data using the Microsoft Form and analyzed using Microsoft Excel and R-program. RESULTS: Of the 418 vaccine recipients, the incidence rate of AEFI (Adverse Events Following Immunization) was 54.31%. Fever, fatigue, and headache were the most commonly reported systemic AEFIs. Among these, 54.7% of AEFI were mild, 42.38% were of the moderate category, and only 2.96% were of grade 3 severity. None of the AEFIs were severe enough for hospitalization. Most of them developed symptoms within 24 hours of the first dose. Complete recovery from AEFIs took a median time of 24 hours. CONCLUSION: Most of our study findings were consistent with the phase 1, 2/3 trials findings of Oxford-AstraZeneca's ChAdOx1 vaccine. The AEFI symptoms were considered immune reactions to the vaccine. The AEFIs were more common among younger individuals and females. The chance of missing a serious adverse event like a thromboembolic phenomenon cannot be ruled out. We observed low AEFI rates with COVISHIELD in the Indian population compared to Oxford-AstraZeneca's ChAdOx1 vaccine in the UK-based population, which can be explained by pre-existing immunity against adenovirus in the Indian population. However, based on the study findings, we may interpret that the COVISHIELD, Serum Institute of India, carries a good safety profile overall.

The winding 12-month journey of the AstraZeneca COVID-19 vaccine since its first administration to humans.

The deficiently designed and conducted initial clinical development plan and the occurrence of thrombotic thrombocytopenia cases, have marked the 12-month journey of the AstraZeneca coronavirus disease 2019 (COVID-19) vaccine after it was first administered to humans. When it was authorized, there were no available efficacy data in the elderly. However, this age group was included in the product labelling based on immunogenicity data. The lack of safety and efficacy data in the elderly that was acknowledged in the product information, triggered most European Union (EU) countries to limit the administration of this vaccine to certain age groups. In February-March/2021, after the results of observational studies supported the vaccine effectiveness in the elderly, several countries broadened its use to this age group. When trust on the vaccine was ramping up, unusual blood clot cases were described in Europe, which led 24 countries around the world to temporarily halt its administration. These cases were first described as thrombotic thrombocytopenia in late March. In mid-April, the UK Medicines and Healthcare products Regulatory Agency (MHRA) and the European Medicines Agency (EMA) updated the product information and confirmed the positive benefit/risk ratio of the vaccine, recommending its use with no age restrictions. The World Health Organization (WHO) coincided with this approach. However, several countries decided to limit its use to certain age groups. The EMA listed thrombotic thrombocytopenia as a "very rare" adverse reaction. Although, the AstraZeneca vaccine was conceived in early 2020 to be a worldwide leader in the fight against COVID-19, its use was abandoned by the African Union, Denmark, and Israel. However, this vaccine has shown its usefulness in many settings across the world.

Safety Monitoring of Covid-19 Vaccine: In a Tertiary Care Hospital in Haryana

Objective: The present study aimed to ensure the safety and related potential adverse effects following ChAdOx1 nCoV-19 vaccination (AZD1222) in a scenario when numerous vaccines have been approved on an emergency basis by the WHO and other regulatory agencies to prevent the widespread of COVID-19 infection and to decrease the associated mortality and morbidity. Method(s): This study was an open, non-comparative, non-interventional, observational study conducted on healthcare workers of BPS Govt. medical college for women and elderly people who received the first dose of COVID-19 vaccinationChAdOx1 nCoV-19 vaccine (AZD1222) by conducting their interviews and recording the data Results: Between January and March 2021, a total of 1907 participants were enrolled in this study. Out of 1907 recipients, 70 recipients reports adverse drug events following vaccination. Myalgia (0.629%), headache (1.31%), fever >=(37.5 degreeC, 0.839%) and fever with chills (>= 37.5 degreeC, 1.048) were the most common adverse events after the first dose of vaccination of ChAdOx1 nCoV-19 vaccine (AZD1222. Throat irritation (0.209 %) and Generalised itching (0.262) were the least common adverse events. Conclusion(s): ChAdOx1 nCoV-19 (Astrazeneca) has an acceptable safety profile as observed in this study. To our knowledge, very few studies are done that review the safety of COVID-19 vaccines. Further safety data from a larger sample size and of longer duration are warranted to establish safetyCopyright © 2023 Innovare Academics Sciences Pvt. Ltd. All rights reserved.

Immunogenicity and reactogenicity of heterologous prime-boost vaccination with inactivated COVID-19 and ChAdOx1 nCoV-19 (AZD1222) vaccines, a quasi-experimental study.

The global supply of COVID-19 vaccines has been limited, and concerns have arisen about vaccine supply chain disruptions in developing countries. Heterologous prime-boost vaccination, which involves using different vaccines for the first and second doses, has been proposed to enhance the immune response. We aimed to compare the immunogenicity and safety of a heterologous prime-boost vaccination using an inactivated COVID-19 vaccine and AZD1222 vaccine with that of a homologous vaccination using AZD1222. This pilot involved 164 healthy volunteers without prior SARS-CoV-2 infection aged 18 years or older assigned to receive either the heterologous or homologous vaccination. The results showed that the heterologous approach was safe and well-tolerated, although the reactogenicity of the heterologous approach was higher. At 4 weeks after receiving the booster dose, the heterologous approach elicited a non-inferior immune response compared to the homologous approach in neutralizing antibody and cell-mediated immune response. The percentage of inhibition was 83.88 (79.72-88.03) in the heterologous and 79.88 (75.50-84.25) in the homologous group, a mean difference of 4.60 (-1.67-10.88). The geometric mean of interferon-gamma was 1072.53 mIU/mL (799.29-1439.18) in the heterologous group and 867.67 mIU/mL (671.94-1120.40) in the homologous group, a GMR of 1.24 (0.82-1.85). However, the binding antibody test of the heterologous group was inferior to the homologous group. Our findings suggest that the use of heterologous prime-boost vaccination with different types of COVID-19 vaccines is a viable strategy, especially in settings where vaccine supply is limited or where vaccine distribution is challenging.

Minimal change disease (MCD) following vaccination with ChAdOx1 nCoV-19 vaccine in a young Indian male: A case report.

Various vaccines against coronavirus disease 2019 (COVID-19) have been developed amidst the ongoing pandemic. Few cases of glomerulonephritis after COVID-19 vaccination have been reported globally. We present a case of nephrotic syndrome due to minimal change disease (MCD) most likely associated with the ChAdOx1 nCoV-19 vaccine. A 24-year-old male presented with anasarca and frothy urine after receiving the first dose of the COVID-19 vaccine. On admission, the patient had normal serum creatinine with 24-h urinary protein excretion of 4.1 g/day and severe hypoalbuminemia. Kidney biopsy revealed nonproliferative glomerular morphology with relatively unremarkable-appearing glomeruli on light microscopy and diffuse effacement of the odocyte foot processes on electron microscopy, consistent with diagnosis of MCD. This case highlights the risk of new-onset nephrotic syndrome due to MCD after COVID-19 vaccination.

Potential mechanisms of vaccine-induced thrombosis.

Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is a rare syndrome characterized by high-titer anti-platelet factor 4 (PF4) antibodies, thrombocytopenia and arterial and venous thrombosis in unusual sites, as cerebral venous sinuses and splanchnic veins. VITT has been described to occur almost exclusively after administration of ChAdOx1 nCoV-19 and Ad26.COV2.S adenovirus vector- based COVID-19 vaccines. Clinical and laboratory features of VITT resemble those of heparin-induced thrombocytopenia (HIT). It has been hypothesized that negatively charged polyadenylated hexone proteins of the AdV vectors could act as heparin to induce the conformational changes of PF4 molecule that lead to the formation of anti-PF4/polyanion antibodies. The anti-PF4 immune response in VITT is fostered by the presence of a proinflammatory milieu, elicited by some impurities found in ChAdOx1 nCoV-19 vaccine, as well as by soluble spike protein resulting from alternative splice events. Anti-PF4 antibodies bind PF4, forming immune complexes which activate platelets, monocytes and granulocytes, resulting in the VITT's immunothrombosis. The reason why only a tiny minority of patents receiving AdV-based COVID-19 vaccines develop VITT is still unknown. It has been hypothesized that individual intrinsic factors, either acquired (i.e., pre-priming of B cells to produce anti-PF4 antibodies by previous contacts with bacteria or viruses) or inherited (i.e., differences in platelet T-cell ubiquitin ligand-2 [TULA-2] expression) can predispose a few subjects to develop VITT. A better knowledge of the mechanistic basis of VITT is essential to improve the safety and the effectiveness of future vaccines and gene therapies using adenovirus vectors.

Covid-19 vaccine (covishield) heralding Moyamoya angiopathy

Indroduction: Thrombotic complications leading to cerebrovascular events occuring in conjunction with Covid-19 vaccination though rare, is well-documented. Moyamoya Angiopathy is a progressive intracranial vasculopathy leading to recurrent strokes. Case presentation: We present two index cases of young patient presenting with stroke and TIA following Covid-19 vaccination (COVISHIELD) leading to unmasking of Moyamoya Angiopathy. Conclusion(s): Arterial stroke following Covid-19 vaccination is documented, but uncommon. However, in the background of a vasculopathy, it may not be so rare. Moyamoya Angiopathy has been closely studied in the model of inflammatory pathophysiology in genetically predisposed patients leading to progressive vaso-occlusive disease. Few reports of Covid-19 infection potentiating Moyamoya Angiopathy symptoms are also documented. Thus, as an extrapolation of the inflammatory etiopathogenesis of Moyamoya Angiopathy, Covid-19 vaccination can similarly affect the Moyamoya symptomatology. These two index cases open new lines of enquiry regarding the interplay of Covid-19 vaccination and neurological destabilization in patients with underlying vasculopathy of inflammatory pathophysiology.Copyright © 2022

Acute hemorrhagic leukoencephalitis after administration of the first dose of ChAdOx1 nCoV-19 SARS-CoV-2 (COVISHIELDTM) vaccine

Background: Many central and peripheral nervous system complications, following COVID-19 vaccination, have been described. We report an unusual case of central demyelinating disorder, following the administration of the ChAdOx1 nCoV-19 SARS-CoV-2 (COVISHIELDTM) vaccine. Case-report: The 28-year female developed sudden onset headache followed by weakness of the left upper and lower limbs, and gait ataxia. Neurological symptoms developed two weeks after administration of the first dose of the ChAdOx1 nCoV-19 SARS-CoV-2 (COVISHIELDTM) vaccine. Magnetic resonance imaging brain revealed T2/FLAIR hyperintense lesions involving bilateral subcortical white matter, splenium of the corpus callosum, and both cerebellar hemispheres. Few lesions showed blooming on gradient echo sequence suggestive of a hemorrhagic component. Post-contrast T1 images showed mild enhancement of demyelinating lesions. The patient was treated intravenously with methylprednisolone. After 12 weeks of follow-up, there was a substantial improvement in her symptoms. She became independent in all her activities of daily living. Conclusion(s): In conclusion, this is an unusual case of acute hemorrhagic leukoencephalitis following ChAdOx1 nCoV-19 SARS-CoV-2 (COVISHIELDTM) vaccination.Copyright © 2022 The Author(s)

Evaluation of humoral immune response after ChAdOx1 nCoV-19 vaccination among health care workers

We assessed the immunogenicity of ChAdOx1 nCoV-19 vaccination by evaluating the levels of SARS-CoV-2 IgG after vaccination and investigated the effect of diverse factors such as gender, age, and adverse reactions after vaccination. The study included a total of 1028 serum samples from 452 healthcare workers. SARS-CoV-2 IgG levels were assessed using the SARS-CoV-2 IgG II Quant assay. Participants completed a questionnaire regarding the intensity and duration of adverse reactions after vaccination. The seropositive rates after the first and second doses were 95.5% and 100%, respectively. The median antibody levels after the second dose showed a 4.2-fold increase compared with the first. Five months after the second dose, the median antibody levels decreased by 3.5-fold. The antibody levels in men were lower than those in women after the first dose and were higher after the second dose. There was no difference according to age groups after the first dose, but after the second dose, in subjects aged 50 and above, the rise in antibody levels was less than that in other age groups. The antibody levels among participants with moderate or severe symptoms were significantly higher than those among participants with mild symptoms after the first dose. There were no statistically significant differences according to the duration of symptoms. We could assume that different age groups and genders might have different immunogenicity following vaccination. The intensity of adverse symptoms was positively correlated with the antibody levels, implying that higher immunogenicity is related to the intensity of adverse symptoms after vaccination. © 2023 The Scandinavian Foundation for Immunology.

Immunogenicity Differences of the ChAdOx1 nCoV-19 Vaccine According to Pre-Existing Adenovirus Immunity.

This study investigated the immunogenicity of, and reactogenicity to, the ChAdOx1 nCoV-19 vaccine according to pre-existing adenovirus immunity. Individuals scheduled for COVID-19 vaccination were prospectively enrolled in a tertiary hospital with 2400 beds from March 2020 onwards. Pre-existing adenovirus immunity data was obtained before ChAdOx1 nCoV-19 vaccination. A total of 68 adult patients administered two doses of the ChAdOx1 nCoV-19 vaccine were enrolled. Pre-existing adenovirus immunity was identified in 49 patients (72.1%), but not in the remaining 19 patients (27.9%). The geometric mean titer of S-specific IgG antibodies was statistically higher in individuals without pre-existing adenovirus immunity at several time points: before the second ChAdOx1 nCoV-19 dose (56.4 (36.6-125.0) vs. 51.0 (17.9-122.3), p = 0.024), 2-3 weeks after the second ChAdOx1 nCoV-19 dose (629.5 (451.5-926.5) vs. 555.0 (287.3-926.0), p = 0.049), and 3 months after the second ChAdOx1 nCoV-19 dose (274.5 (160.5-655.3) vs. 176.0 (94.3-255.3), p = 0.033). In the absence of pre-existing adenovirus immunity, systemic events were observed with higher frequency, especially chills (73.7% vs. 31.9%, p = 0.002). In conclusion, individuals without pre-existing adenovirus immunity showed a higher immune response to ChAdOx1 nCoV-19 vaccination and a higher frequency of reactogenicity to ChAdOx1 nCoV-19 vaccination was observed.

Differential T-cell and antibody responses induced by mRNA versus adenoviral vectored COVID-19 vaccines in patients with immunodeficiencies.

Background: Immunodeficient patients (IDPs) are at higher risk of contracting severe coronavirus disease 2019 (COVID-19). Targeted vaccination strategies have been implemented to enhance vaccine-induced protection. In this population, however, clinical effectiveness is variable and the duration of protection unknown. Objective: We sought to better understand the cellular and humoral immune responses to mRNA and adenoviral vectored COVID-19 vaccines in patients with immunodeficiency. Methods: Immune responses to severe acute respiratory syndrome coronavirus 2 spike were assessed after 2 doses of homologous ChAdOx1-nCoV-19 or BNT162b2 vaccines in 112 infection-naive IDPs and 131 healthy health care workers as controls. Predictors of vaccine responsiveness were investigated. Results: Immune responses to vaccination were low, and virus neutralization by antibody was not detected despite high titer binding responses in many IDPs. In those exhibiting response, the frequency of specific T-cell responses in IDPs was similar to controls, while antibody responses were lower. Sustained vaccine specific differences were identified: T-cell responses were greater in ChAdOx1-nCoV-19- compared to BNT162b2-immunized IDPs, and antibody binding and neutralization were greater in all cohorts immunized with BNT162b2. The positive correlation between T-cell and antibody responses was weak and increased with subsequent vaccination. Conclusion: Immunodeficient patients have impaired immune responses to mRNA and viral vector COVID-19 vaccines that appear to be influenced by vaccine formulation. Understanding the relative roles of T-cell- and antibody-mediated protection as well as the potential of heterologous prime and boost immunization protocols is needed to optimize the vaccination approach in these high-risk groups.

Vaccine-induced immune thrombotic thrombocytopenia post dose 2 ChAdOx1 nCoV19 vaccination: Less severe but remains a problem.

BACKGROUND: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but established complication of 1st dose ChAdOx1 nCoV19 vaccination (AZD1222), however this complication after dose 2 remains controversial. OBJECTIVES: To describe the clinicopathological features of confirmed cases of VITT post dose 2 AZD1222 vaccination in Australia, and to compare this cohort to confirmed cases of VITT post 1st dose. METHODS: Sequential cases of clinically suspected VITT (thrombocytopenia, D-Dimer > 5x upper limit normal and thrombosis) within 4-42 days of dose 2 AZD1222 referred to Australia's centralised testing centre underwent platelet activation confirmatory testing in keeping with the national diagnostic algorithm. Final classification was assigned after adjudication by an expert advisory committee. Descriptive statistics were performed on this cohort and comparative analyses carried out on confirmed cases of VITT after 1st and 2nd dose AZD1222. RESULTS: Of 62 patients referred, 15 demonstrated presence of antibody mediated platelet activation consistent with VITT after dose 2 AZD1222. Four were immunoassay positive. Median time to presentation was 13 days (range 1-53) platelet count 116x10^9/L (range 63-139) and D-dimer elevation 14.5xULN (IQR 11, 26). Two fatalities occurred. In each, the dosing interval was less than 30 days. In comparison to 1st dose, dose 2 cases were more likely to be male (OR 4.6, 95% CI 1.3-15.8, p = 0.03), present with higher platelet counts (p = 0.05), lower D-Dimer (p = 01) and less likely to have unusual site thromboses (OR 0.14, 95% CI 0.04-0.28, p = 0.02). CONCLUSIONS: VITT is a complication of dose 2 AZD1222 vaccination. Whilst clinicopathological features are less severe, fatalities occurred in patients with concomitant factors.

Safety, immunogenecity and effectiveness of ChAdOx1 nCoV-19 vaccine during the second wave of pandemic in India: a real-world study.

OBJECTIVES: This real-world study was conducted to assess the adverse effects following immunization (AEFI) and immunogenicity of ChAdO×1 nCoV-19 vaccine in terms of neutralising antibody titers and to study the effects of covariates such as age, sex, comorbidities and prior COVID status on these outcomes. Also, the effectiveness of the vaccine based on interval between the two doses was also investigated. METHODS: A total of 512 participants (M/F=274/238) aged 35(18-87) years comprising a mixed population of healthcare workers, other frontline workers and general public were enrolled between March and May 2021. Records for adverse events if any were collected telephonically by following up with participants up to 6 months post first dose and graded as per Common Terminology Criteria for Adverse Events (CTCAE) version 5. Blood samples for measuring antibody titers against the receptor binding domain (RBD) were collected serially using a convenient sampling strategy up to 6 months after the first dose. Data on breakthrough COVID infection was collected telephonically till December 2021. RESULTS: Incidence of local reactions was higher after first dose at 33.4 % (171/512) compared to those after second dose at 12.9 % (66/512). Commonest side effect observed was injection site pain after the first (87.1 %; 149/171) and second (87.9 %; 56/66) dose respectively. Among systemic reactions, fever was the most common manifestation followed by myalgia and headache. Female sex (p<0⸱001) and age less than 60 years (p<0⸱001) had significantly higher predilection for systemic toxicities. Age ≤60 years (p=0.024) and prior-COVID (p<0.001) were found to be significantly associated with higher antibody titers, however, no association was found between these variables and breakthrough COVID infection. Longer spacing between the doses (≥6 weeks) was found to offer better protection against breakthrough infection compared to a spacing of 4 weeks. All breakthroughs were mild-moderate in severity, not requiring hospitalization. CONCLUSIONS: The ChAdOx1 nCov-19 vaccine is apparently safe and effective against SARS-CoV-2 virus infection. Prior COVID infection and younger age group achieve higher antibody titers, but no additional protection. Delaying the second dose up to at least 6 weeks is more effective compared to shorter spacing between doses.