Nephrotic Syndrome in Adult Patients With COVID-19 Infection or Post COVID-19 Vaccine: A Systematic Review.

Nephrotic syndrome is a condition characterized by damage to podocytes that results in significant proteinuria, edema, hyperlipidemia, and hypercoagulability. Infections and malignancies are frequently associated with nephrotic syndrome. The COVID-19 virus has been associated with several atypical presentations of upper respiratory infections and acute kidney injury. Considering that COVID-19 causes systemic inflammatory changes, it seems plausible that it may also lead to nephrotic syndrome. This study aimed to investigate if an association between COVID-19 and the different types of nephrotic syndromes exists. Data were extracted into a spreadsheet. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS, IBM Corp., Armonk, NY, USA). We performed a systematic search of PubMed/Medline and Embase databases using both medical subject headings (MeSH) and regular keywords associated with COVID-19 and nephrotic syndrome, including different types of nephrotic syndromes. The search was performed on 17th December 2021. We included case reports and case series about adult patients who developed findings suggestive of nephrotic syndrome shortly after infection or vaccination. We excluded cases involving children, pregnant women, articles written in languages other than English, and those that were not retrievable. The relevance and quality of identified articles were assessed. We included 32 articles in the study, primarily case reports and case series. In our study, COVID-19 and the COVID-19 vaccine have been associated with the development of nephrotic syndrome, primarily a collapsing form of focal segmental glomerulosclerosis, although other forms have been observed as well. There was little consistency in patient histories, clinical presentations, clinical courses, or treatment regimens, although it appeared that most cases eventually resolved. More cases need to be reported and analyzed before more definitive conclusions can be reached. In conclusion, nephrotic syndrome is a possible complication of both COVID-19 infection and the COVD-19 vaccine and should be considered in patients exhibiting sudden onset edemas or deterioration in kidney function. While the majority of cases respond to standard treatment, clearer guidelines will need to be developed once more data is available.

Analysis on the research progress and prospect of novel coronavirus vaccine

The novel coronavirus disease 2019 (2019-NCOV), caused by the novel coronavirus (2019-NCOV), is raging around the world and has become an important global public health problem threatening human health. Since the outbreak in 2019, as of early October 2022, the cumulative confirmed cases of COVID-19 have reached 615, 689, 999 and the cumulative death cases have reached 6, 526, 739. The top five countries with the most confirmed cases are the United States, India, France, Brazil, and Germany. Currently, many people worldwide are still at risk of morbidity and mortality from SARS-CoV-2 and COVID-19. In the absence of specific drugs, vaccination is undoubtedly the most effective way to block the spread of the virus. As of July 2022, 16 vaccines have been approved for marketing or emergency use, and more than 250 vaccines are under development, among which 167 are in phase III clinical trials. By September 2022, nine vaccines had been conditionally marketed or approved for emergency use in China. This paper mainly reviews the specific characteristics and research and development status of various COVID-19 vaccines, as well as their safety and effectiveness. In addition, the future trends and challenges of vaccine research and development are analyzed based on the current situation. © 2023 SPIE.

Immunogenicity Characterization of COVID-19 Vaccines: A Systematic Review and Meta-analysis

Introduction: Immunogenicity has emerged as a challenge in the development of vaccines against coronavirus disease of 2019 (COVID-19). Immunogenicity is a determinant of the efficacy and safety of vaccines. This systematic review and associated meta-analysis summarized and characterized the immunogenicity of COVID-19 vaccines in randomized controlled trials (RCTs). Methods: Relevant RCTs were systematically sourced from different medical databases in August 2021. The risk ratios and mean differences with 95% confidence intervals were calculated. Results: Of 2,310 papers, 16 RCTs were eligible for review. These RCTs involved a total of 26,698 participants (15,292 males and 11,231 females). The pooled results showed a significant difference in the geometric mean titer between the vaccinated and control groups in favor of the vaccine group after 1 and 2 months of follow-up, for the young age group (18 -< 55y), and with different doses (P < 0.001). The difference in the older age group (>55y) was insignificant (P = 0.24). The seroconversion rate of spike neutralizing antibodies favored the vaccine groups 1 or 2 months after vaccination (P < 0.001). The seroconversion rate of the vaccine group was significantly different (P < 0.001) from that of the control group. Conclusions: Vaccination elicits immunogenicity in the follow-up period for all age groups and at low and large doses. Therefore, people should be encouraged to receive vaccines currently being offered. A boost dose has been asserted for the elderly.

Myocarditis following Coronavirus vaccination

Introduction: Myocarditis is an adverse reaction discovered after the marketing of SARS-CoV-2 mRNA vaccines. Nevertheless, this effect is not mentioned as an adverse reaction in the summary of product characteristics of other types of vaccines against this disease. Objective(s): In this work, we aim to present the cases of myocarditis after vaccination against COVID-19 reported to the national Tunisian centre of pharmacovigilance. Method(s): We present the cases of myocarditis reported after the COVID-19 vaccination. All cases are diagnosed according to Brighton's case definition of myocarditis. The vaccines causality assessment was estimated by the French imputability updated method of Begaud et al. Result(s): We included five patients. The sex ratio (M/F) was 4. The mean age was 30 years. All patients had no notable cardiovascular history and did not report any significant past medical history. The onset of symptoms was two days post-vaccination in three patients. The predominant reported symptoms are chest pain and dyspnea in the five cases. Cardiac magnetic resonance imaging (MRI) confirmed the myocarditis diagnosis in four patients (not performed for one patient). All cases were classified as definitive cases according to the Brighton case definition of myocarditis. No patient required hospitalization in a cardiac intensive care unit. All the patients recovered from acute myocarditis within a few days. Conclusion(s): Reported cases of myocarditis post-COVID-19 vaccination in our population are rare, not severe, and have a quick favorable outcome.Copyright © 2022

Insight into women with dermal fillers perceptions in Riyadh to uptake the Coronavirus vaccine.

Background: Vaccination is considered to be the ideal way for population immunity, and willingness in taking the COVID-19 vaccine has been a controversial issue worldwide. The commonly reported adverse events of the COVID-19 vaccination have made people question the safety of the vaccine, especially for women with dermal filler and using cosmetics injections. It has been reported that some COVID-19 vaccines can cause side effects in women with dermal filler injections. In this study, we aimed to assess the perception and attitude of females with dermal fillers in Riyadh towards the COVID-19 vaccine using a self-answered questionnaire. Methods: A total of 352 females participated in the study of different ages and nationalities. our study findings indicate that the mean knowledge and attitude scores of females with dermal fillers regarding the COVID-19 vaccine are sub-optimal. Results: Knowledge is significantly related to factors such as educational level, and chronic disease status, while attitude scores are significantly associated with nationality, educational level, COVID-19 vaccination status, previous history of taking the seasonal flu vaccine, and source of information related to COVID-19. Conclusion: These findings suggest the need to increase awareness regarding the COVID-19 vaccine and improve the attitude toward it.

Fc-mediated pan-sarbecovirus protection after alphavirus vector vaccination.

Group 2B ß-coronaviruses (sarbecoviruses) have caused regional and global epidemics in modern history. Here, we evaluate the mechanisms of cross-sarbecovirus protective immunity, currently less clear yet important for pan-sarbecovirus vaccine development, using a panel of alphavirus-vectored vaccines covering bat to human strains. While vaccination does not prevent virus replication, it protects against lethal heterologous disease outcomes in both severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and clade 2 bat sarbecovirus challenge models. The spike vaccines tested primarily elicit a highly S1-specific homologous neutralizing antibody response with no detectable cross-virus neutralization. Rather, non-neutralizing antibody functions, mechanistically linked to FcgR4 and spike S2, mediate cross-protection in wild-type mice. Protection is lost in FcR knockout mice, further supporting a model for non-neutralizing, protective antibodies. These data highlight the importance of FcR-mediated cross-protective immune responses in universal pan-sarbecovirus vaccine designs.

Pro or Anti? A Social Influence Model of Online Stance Flipping

Social influence characterizes the change of an individual's stances in a complex social environment towards a topic. Two factors often govern the influence of stances in an online social network: endogenous influences driven by an individual's innate beliefs through the agent's past stances and exogenous influences formed by social network influence between users. Both endogenous and exogenous influences offer important cues to user susceptibility, thereby enhancing the predictive performance on stance changes or flipping. In this work, we propose a stance flipping prediction problem to identify Twitter agents that are susceptible to stance flipping towards the coronavirus vaccine (i.e., from pro-vaccine to anti-vaccine). Specifically, we design a social influence model where each agent has some fixed innate stance and a conviction of the stance that reflects the resistance to change;agents influence each other through the social network structure. From data collected between April 2020 to May 2021, our model achieves 86% accuracy in predicting agents that flip stances. Further analysis identifies that agents that flip stances have significantly more neighbors engaging in collective expression of the opposite stance, and 53.7% of the agents that flip stances are bots and bot agents require lesser social influence to flip stances. © 2013 IEEE.

Socioeconomic and demographic characteristics influencing the hesitancy and refusal of COVID-19 vaccine in Ghana.

Background: Ghana was the first country to receive the coronavirus vaccination in West Africa from AstraZeneca or Oxford. Ghana plans to vaccinate 20 million out of the 32 million population and provide the necessary doses utilizing multilateral and bilateral agreements. As Ghana begins vaccinating its citizens, there is some skepticism about administering the coronavirus vaccine (CVV). This research aimed to analyze the socioeconomic and demographic characteristics influencing vaccine hesitancy (VH) and refusal among Ghanaians. Methods: The multinomial logistics regression model was employed to investigate the relationship between respondents' socio-demographic characteristics and VH. The research data were gathered between March to June 2021 through an online survey. Findings: The findings of this study indicated that approximately 92.75% of the 400 respondents have heard about CVV. The study suggests that less than 5% of the participants have so far received the CVV. Most of the respondents (36.8%) indicated rejecting the CVV. Interestingly, male participants [adjusted odds ratio (AOR) = 1.048; 95% confidence interval (CI): 0.532-2.063] with higher educational backgrounds (AOR = 2.11; 95% CI: 0.870-5.121) had higher odds of being CVV hesitant or refusers. Low economic class, rural settlers, unmarried individuals, and unemployed people also had higher odds of being VH or refusers. The survey also shows that most Ghanaians refused to receive the CVV because they did not trust the system to track the vaccine's side or adverse effects. Conclusion: Government can use social media platforms and other media platforms to effectively provide relevant information regarding the full benefit and risks of taking the virus.

Evaluation of the Effect of Infection and Immunity on the Tear Film by Scheimpflug-Placido Disc Topography- A Case Control Study.

PURPOSE: We aimed to compare the tear film stability of individuals who had recovered from coronavirus disease (COVID-19), that of individuals vaccinated against COVID-19 and that of healthy individuals in a control group. METHODS: This study included 61 eyes of 61 post-COVID-19 patients, 63 eyes of 63 participants who had received at least two doses of the SARS-CoV-2 mRNA BNT162b2 (Pfizer-BioNTech) vaccine, and 57 eyes of healthy individuals in a control group. We compared the groups' tear film stability. RESULTS: The mean non-invasive first tear break-up time (NIF-BUT) value was 4.1±2.7 seconds in the post-COVID-19 group, 4.7±2.9 seconds in the vaccinated group, and 5.8±2.8 seconds in the control group. This value was statistically significantly lower in the post-COVID-19 and vaccinated groups than in the control group (p= 0.007). The rate of superotemporal (ST) quadrant breakup, statistically significantly higher in the vaccinated group than in the other two groups (p=0.001). According to a qualitative examination of the results, at least one breakup occurred in 47 (77%) of the post-COVID-19 participants' eyes, 50 (79.4%) of the vaccinated group's eyes, and 33 (57.9%) of the control group's eyes. In terms of this qualitative value, the post-COVID-19 and vaccinated groups had significantly higher breakup rates than the control group (p=0.018). CONCLUSIONS: Destabilization in the tear film was more common in both the post covid group and the vaccinated group. In addition to individuals who have post-Covid, we think that post-vaccination individuals should be followed closely in terms of ocular surface diseases.

Coronavirus Vaccination Hesitancy: Early Education to Counter Vaccine Hesitancy/Refusal.

The coronavirus infection has resulted in more than 1 million deaths in the United States. The momentary enthusiasm that came with introducing the coronavirus disease (COVID) vaccine soon faded away due to the public's hesitant reaction toward the coronavirus vaccine. COVID vaccine hesitancy creates an enormous problem in the fight to eradicate the coronavirus infection. This hesitancy highlights gaps in knowledge between public health organizations, educational institutions, and public perception of COVID vaccines. Therefore, these stakeholders should consider a collaborative action to introduce vaccine education in grade school. Such a curriculum could facilitate a better understanding of how vaccines prevent infectious diseases.

Decision-making on childhood vaccination against COVID-19 by nurses in Cyprus: A cross-sectional online survey.

Individuals with high health literacy, such as healthcare workers, are expected to appreciate vaccination benefits and ensure the vaccination of their children. The objective of this study was to examine the factors influencing nurses' decision to vaccinate their children against COVID-19. An online cross-sectional study was conducted in December 2020 (8th-28th), before COVID-19 vaccine availability in Cyprus, and employed an anonymous self-administered survey with questions related to socio-demographic characteristics, general vaccine knowledge, and COVID-19 vaccination. Three hundred five nurses with at least one minor child completed the online questionnaire. A small proportion of participants (15.2%) planned to get their children vaccinated against COVID-19. Interestingly, a higher level of vaccination knowledge score was linked with increased likelihood of vaccination intention (OR = 1.35, 95% CI:1.08-1.68), which remained statistically significant after adjusting for age and gender (OR = 1.33, 95% CI:1.06-1.66), socioeconomic (OR = 1.35, 95% CI:1.07-1.70), and demographic characteristics (OR = 1.38, 95% CI:1.07-1.77). Specific characteristics such as older age and being married/in cohabitation status were linked to higher odds of accepting the childhood vaccination against COVID-19. Acceptance of childhood vaccination against COVID-19 is linked with nurses' vaccination knowledge, therefore, public health authorities may focus on educational campaigns to promote childhood vaccination.

Pro or Anti? A Social Influence Model of Online Stance Flipping

Social influence characterizes the change of an individual's stances in a complex social environment towards a topic. Two factors often govern the influence of stances in an online social network: endogenous influences driven by an individual's innate beliefs through the agent's past stances and exogenous influences formed by social network influence between users. Both endogenous and exogenous influences offer important cues to user susceptibility, thereby enhancing the predictive performance on stance changes or flipping. In this work, we propose a stance flipping prediction problem to identify Twitter agents that are susceptible to stance flipping towards the coronavirus vaccine (i.e., from pro-vaccine to anti-vaccine). Specifically, we design a social influence model where each agent has some fixed innate stance and a conviction of the stance that reflects the resistance to change;agents influence each other through the social network structure. From data collected between April 2020 to May 2021, our model achieves 86% accuracy in predicting agents that flip stances. Further analysis identifies that agents that flip stances have significantly more neighbors engaging in collective expression of the opposite stance, and 53.7% of the agents that flip stances are bots and bot agents require lesser social influence to flip stances.

COVID-19 Vaccination-Associated Myocarditis: A Literature Review.

Myocarditis is defined as a non-ischemic inflammation of the middle layer of the heart. It ensues changes that can lead to acute heart failure, dilated cardiomyopathy, and sudden death. Myocarditis is caused by several infectious and non-infectious agents. Vaccines are also known to cause myocarditis. The use of the coronavirus disease (COVID-19) vaccination was started to combat the severity of the COVID-19 infection and reduce the mortality and morbidity associated with it. The vaccination, however, caused side effects like myocarditis, among others. In order to investigate the association between the COVID-19 vaccination and myocarditis in adults and adolescents, we conducted a literature review by searching three databases: Google Scholar, PubMed, and ScienceDirect. From the published literature, we found that, though it is rare, the various vaccinations available can cause symptoms of myocarditis as a side effect more commonly in patients who have received both doses of a particular vaccine and that there are significant changes in cardiac magnetic resonance imaging (CMRI) and other biochemical markers, with young males being more commonly affected. Further prospective trial-based studies are required to establish a concrete relationship between myocarditis and the COVID-19 vaccine.

Factors impacting COVID-19 vaccine decision making in older adults and people with underlying conditions in Victoria, Australia: A cross-sectional survey.

Australia's COVID-19 vaccine rollout included prioritizing older adults and those with underlying conditions. However, little was known around the factors impacting their decision to accept the vaccine. This study aimed to assess vaccine intentions, information needs, and preferences of people prioritized to receive the COVID-19 vaccine at the start of the Australian vaccine rollout. A cross-sectional online survey of people aged ≥70 years or 18-69 with chronic or underlying conditions was conducted between 12 February and 26 March 2021 in Victoria, Australia. The World Health Organization Behavioural and Social Drivers of COVID-19 vaccination framework and items informed the survey design and framing of results. Bivariate logistic regression was used to investigate the association between intention to accept a COVID-19 vaccine and demographic characteristics. In total, 1828 eligible people completed the survey. Intention to vaccinate was highest among those ≥70 years (89.6%, n = 824/920) versus those aged 18-69 years (83.8%, n = 761/908), with 91% (n = 1641/1803) of respondents agreeing that getting a COVID-19 vaccine was important to their health. Reported vaccine safety (aOR 1.4, 95% CI 1.1 to 1.8) and efficacy (aOR 1.9, 95% CI 1.5 to 2.3) were associated with intention to accept a COVID-19 vaccine. Concerns around serious illness, long-term effects, and insufficient vaccine testing were factors for not accepting a COVID-19 vaccine. Preferred communication methods included discussion with healthcare providers, with primary care providers identified as the most trusted information source. This study identified factors influencing the prioritized public's COVID-19 vaccine decision-making, including information preferences. These details can support future vaccination rollouts.

An Analysis of the COVID-19 Situation in India in Terms of Testing, Treatment, Vaccine Acceptance and National Economic Performance.

Objectives: This study aims to provide a comprehensive review on the analysis of COVID-19 pandemic in India and address economic impact, diagnosis approaches, and vaccine acceptance and hesitation. Method: We retrieved articles published in 2020 and 2021 and current data from official websites that narrate the strategy for COVID-19 testing, issues, and challenges, healthcare system insufficiency, statistics of cases, deaths, vaccination, and vaccine acceptance barriers, and beliefs. Results: India being the 2nd largest populated country with a population of 1.4 billion faced massive difficulty in controlling the transmission of SARS-CoV-2. This crisis dramatically impeded the economy of the nation. India witnessed 2nd highest number (43,019,453) of confirmed cases and 3rd highest number of deaths (521,004) across the world. Conclusion: The major cause of the collapse of COVID-19 is the high population of India, pre-existing weak healthcare system, and the lack of awareness among the people. The fall, rise, and statistics provided in the review will help in comparing the current status with other countries and in making strong strategies to combat future calamities.

Myocarditis following Coronavirus vaccination

Introduction Myocarditis is an adverse reaction discovered after the marketing of SARS-CoV-2 mRNA vaccines. Nevertheless, this effect is not mentioned as an adverse reaction in the summary of product characteristics of other types of vaccines against this disease. Objective In this work, we aim to present the cases of myocarditis after vaccination against COVID-19 reported to the national Tunisian centre of pharmacovigilance. Method We present the cases of myocarditis reported after the COVID-19 vaccination. All cases are diagnosed according to Brighton's case definition of myocarditis. The vaccines causality assessment was estimated by the French imputability updated method of Bégaud et al. Results We included five patients. The sex ratio (M/F) was 4. The mean age was 30 years. All patients had no notable cardiovascular history and did not report any significant past medical history. The onset of symptoms was two days post-vaccination in three patients. The predominant reported symptoms are chest pain and dyspnea in the five cases. Cardiac magnetic resonance imaging (MRI) confirmed the myocarditis diagnosis in four patients (not performed for one patient). All cases were classified as definitive cases according to the Brighton case definition of myocarditis. No patient required hospitalization in a cardiac intensive care unit. All the patients recovered from acute myocarditis within a few days. Conclusion Reported cases of myocarditis post-COVID-19 vaccination in our population are rare, not severe, and have a quick favorable outcome.

Spectrum of Neurological Complications Following COVID-19 Vaccination in India.

BACKGROUND AND PURPOSE: According to WHO statistics, approximately 6.9 billion people worldwide had been vaccinated against SARS-CoV-2 as at October 27, 2021, including around 1.0 billion people in India. Most Indian recipients received the Covishield (ChAdOx1-S/nCoV-19) vaccine, followed by the Covaxin (an inactivated SARS-CoV-2 antigen) vaccine. This study was conducted to characterize the neurological phenotypic spectrum of patients with adverse events following immunization with any of the available COVID-19 vaccines in India (Covishield or Covaxin) during the study period and their temporal relationship with vaccination. METHODS: This ambispective multicenter hospital-based cohort study covered the period from March to October 2021. The study included all cases suspected of having neurological complications following COVID-19 vaccination. RESULTS: We report a spectrum of serious postvaccination neurological complications comprising primary central nervous system demyelination (4 cases), cerebral venous thrombosis (3 cases), Guillain-Barre syndrome (2 cases), vaccine-induced prothrombotic immune thrombocytopenia syndrome (2 cases), cranial nerve palsies (2 cases), primary cerebral hemorrhage (1 case), vestibular neuronitis (1 case), chronic inflammatory demyelinating polyneuropathy (1 case), generalized myasthenia (1 case), and seizures (1 case). CONCLUSIONS: Although the benefits of vaccination far outweigh its risks, clinicians must be aware of possible serious adverse events associated with COVID-19 vaccinations.

Study on quantitative detection of bacterial endotoxin in recombinant novel coronavirus vaccine (CHO cell) by micro-dynamic chromogenic

Aim To explore the feasibility of the micro- dynamic chromogenic method for quantitative detection of bacterial endotoxin in recombinant novel coronavirus vaccine ( CHO cell).Methods The micro-dynamic color method of Limulus reagent was used to establish a bacterial endotoxin standard curve.The dilution factor was determined through interference pre -experiment, the recoverv rate of the endotoxin added to the test so- J lution was determined, and the interference test to complete the quantitative detection test of the bacterial endotoxin content in the test product was performed, and the results were compared with those of the gel-clot method.Results Hie linear range of the concentration of the standard curve was 0.02 to 2.0 EU * mL 1 , and the regression equation of the standard curve was lgT =-0.302 7 lgC +2.858 7( r = 0.998 9).When recombinant novel coronavirus vaccine ( CHO cell) was cliluted 40 times or below, the micro -dynamic chromogenic reagent did not interfere with the bacterial endotoxin agglutination reaction, and the recovery rate was 50% to 200%.The test results were consistent with the gel- clot method.Conclusions The micro-dynamic chromogenic method can be used for the quantitative detection of bacterial endotoxins in recombinant novel coronavirus vaccine ( CHO cell) with accurate results, high sensitivity, and process monitoring. Copyright © 2022 Publication Centre of Anhui Medical University. All rights reserved.

Effectiveness of ChAdOx1 nCoV-19 coronavius vaccine in preventing severe disease and mortality during the second wave of pandemic: A case-case analysis from a tertiary care center in South India

Objective: To determine the real-world effectiveness of the ChAdOx1 nCoV-19 coronavirus vaccine in preventing severe disease and mortality due to COVID-19. Methods: A case-case design was used to estimate the effect of the ChAdOx1 nCoV-19 coronavirus vaccine on severe SARS-CoV-2 outcomes in individuals aged 40 years and above. Cases (n=200) were COVID-19 patients admitted to intensive care unit (ICU) or who died. Controls (n=223) were those with mild COVID-19, fit for home isolation. The logistic regression model was used to estimate adjusted vaccine effectiveness for full vaccination (two doses >= 14 d) and partial vaccination status (one dose >= 14 d or two doses < 14 d). Results: The proportion of fully vaccinated individuals was significantly lower among cases (12, 6.0%) compared to controls (30, 13.5%). The adjusted effectiveness of a full dose of ChAdOx1 nCoV-19 coronavirus vaccine in preventing ICU admission or death was 81.9% (95% CI: 61.3%-91.6%, P=0.001). Subgroup analysis restricted to age group, sex, and comorbidities found that ChAdOx1 nCoV-19 coronavirus vaccine had a significant positive effect in all subgroups and categories. Conclusion: COVID-19 vaccination reduces ICU admissions or death. Therefore, increased vaccine uptake may reduce the severity of the pandemic, more so in the elderly and those with comorbidities.

Neutralising Antibodies in Healthcare Workers after Two Doses of Covishield Vaccine at Three Months and Six Months: A Single-centre Observational Study

Introduction: The emergence of Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) as a pandemic has put the global population at risk for its infection. It has also led to an accelerated effort to develop vaccines that can mitigate progression to severe infections at a minimum. The ambiguity about existence of antibodies in the human serum poses problem in formulating public health policies like suitable interval between doses of vaccines, appropriate time for vaccinating population, post natural infection, necessity of booster doses along with single dose. Aim: To estimate neutralising antibody level following vaccination of Healthcare Workers (HCWs) after three months and six months respectively. Materials and Methods: This was a prospective observational study performed in Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bengaluru, Karnataka, India after Institutional Ethics Committee (IEC) approval from January 2021 to February 2022. The study was conducted in 304 HCWs in the institute who had received two doses of Recombinant ChAdOx1 nCoV- 19 Corona Virus Vaccine (Covishield). 41 HCWs who were naturally infected with SARS-CoV-2 either before or after vaccination were also included. These participants were then subjected to IgG neutralising antibody titer estimation at three months and six months, postvaccination. Results: The study included 304 eligible HCWs. Majority of the participants belonged to the age group of 31-40 years (35.9%). Majority of the study participants were females (51%). Of the 304 participants, 263 were uninfected and 41 participants had been infected before and after vaccination. At the six month follow-up, it was observed that all but one HCW had seroconverted with majority of the participants showing more than 60% antibody level. Participants in the age group of 31-40 years showed the highest level and this observation was found to be statistically significant. Conclusion: Neutralising antibody response in HCWs is a key indicator of the efficacy of the vaccination program for Coronavirus Disease-2019 (COVID-19) in India.