COVID-19 vaccine hesitancy among school children aged 12-14 years: A cross-sectional study from Bhubaneswar, Odisha, India.

INTRODUCTION: Universal coverage of COVID-19 vaccines is of paramount importance for the prevention and control of the pandemic. World Health Organization (WHO) in 2019 declared vaccine hesitancy as one of the top ten global health threats. The study aims to find out the COVID-19 vaccine hesitancy among school children along with their parent's perspectives. METHODOLOGY: A cross-sectional study was conducted among school children (aged 12-14 years) at two schools in Bhubaneswar, Odisha. Data were collected via web-based links using a semi-structured questionnaire among students and their parents. RESULTS: Of 343 children, 79% (271) showed a strong willingness to get vaccinated. Around 91.8% (315) of parents agreed to get their children vaccinated. Fear of side effects (65.2%) was the most common reason for unwillingness. CONCLUSIONS: With only 1/5th of the children not willing to get vaccinated, policymakers should create a multi-centric effort for the universal coverage of the COVID-19 vaccination.

Seroprevalence of human brucellosis among the tribal and non-tribal population residing in an eastern state of India: Findings from the state-wide serosurvey.

Background: Brucellosis is a neglected zoonotic disease found predominantly in lower- and middle-income countries (LMICs), causing significant public health concern in India. The objective of this study was to assess the prevalence of human brucellosis in Odisha, India among community members involved in animal husbandry as a common practice. Method: This cross-sectional study included 817 adult participants from 11 districts in Odisha. Four districts from the Northern division, four districts from the Central division, and three districts from the Southern division were selected for the study. Blood samples were collected during a COVID-19 serosurvey in Odisha conducted from 1st to 17th September 2021. Immunoglobulin-G (IgG) antibodies were measured against Brucella using a commercial ELISA kit. Point estimates at 95% confidence intervals (CIs) and adjusted odds ratio were calculated. Results: The overall prevalence of anti-Brucella IgG antibodies was calculated at 16.65% (95% CI: 14.19-19.42). The highest seropositivity was found in Sambalpur district (29.73%; 95% CI: 16.43-47.16) and the lowest was determined in Mayurbhanj district (4.44%; 95% CI: 0.99-15.60). Compared to males, females were more prone to contracting the disease (AOR: 1.13; 95% CI: 1.05-1.67). Participants from rural settings had higher prevalence of anti-Brucella IgG antibodies than urban dwellers (AOR: 4.53; 95% CI: 1.73-11.86). Conclusion: This study revealed that human brucellosis was associated with sociodemographic factors like gender, living settings, and household numbers. To prevent brucellosis, screening should be initiated, infected humans should be treated early, and the public should be educated about risk factors and preventive measures.

Hepatitis B virus infection among the tribal and particularly vulnerable tribal population from an eastern state of India: Findings from the serosurvey in seven tribal dominated districts, 2021-2022.

The Global Health Sector Strategy on viral hepatitis (2016-2021) endorsed by the World Health Assembly in 2016, called for the elimination of viral hepatitis as a public health threat by 2030. Odisha, an eastern state of India, has the third-highest percentage of tribal population in the country and limited information is available regarding the prevalence of HBsAg among them. The present study was undertaken to estimate the seroprevalence of hepatitis B surface antigen as well as HBV DNA almost after 12 years of the first prevalence study of HBsAg among the tribal community of Odisha. The present study attempted to estimate the prevalence of HBsAg among the 35 Scheduled tribal (ST) communities and 5 Particularly Vulnerable Tribal Group (PVTG) using the 2,737 number of sera collected as part of a statewide COVID-19 serosurvey, among the tribal populations of Odisha (residing in 7 districts) aged 6-75 years. HBsAg positivity ranged between 1.79 and 2.94% across various age groups. 42.9% of HBsAg positive individuals showed the presence of HBV DNA and the high viral load was 0.10 × 102-6.84 × 108 IU/mL, indicating a high potential to transmit the virus. The HBsAg positivity was 14.18 and 6.06% among the PVTGs, Kutia Khond and Paudi Bhuyan, who were first time surveyed for HBsAg prevalence. The present study documents the prevalence of HBsAg among the major tribal population residing in the eastern state of the country and highlights the need for a statewide survey of Hepatitis B infection and risk factors, coverage and impact of the Hepatitis B vaccination program introduced in 2010-2011 in Odisha among the ST and PVTG population of the state.

Serological survey for SARS-CoV-2 antibodies among tribal communities of Odisha post-second wave.

Background & objectives: Serial national level serosurveys in India have provided valuable information regarding the spread of COVID-19 pandemic in the general population, but the impact of the ongoing pandemic on the tribal population in India is not well understood. In this study, we evaluated the seroprevalence of COVID-19 antibodies in the tribal population of Odisha post-second wave (September 2021). Methods: A population-based, age-stratified, cross-sectional study design was adopted for the survey, carried out in seven tribal districts of Odisha from 30th August to 16th September 2021. A multistage random sampling method was used where serum samples were tested for antibodies against the SARS-CoV-2 nucleocapsid (N) protein in each district, and a weighted seroprevalence with 95 per cent confidence interval (CI) was estimated for each district. Results: A total of 2855 study participants were included from the seven tribal districts of Odisha in the final analysis. The overall weighted seroprevalence was 72.8 per cent (95% CI: 70.1-75.3). Serological prevalence was the highest among 18-44 yr (74.4%, 95% CI: 71.3-77.3) and from Sambalpur district [75.90% (66.90-83.10)]. Among participants, 41.93 per cent had received at least one dose of any COVID-19 vaccine. Kandhamal district had the highest number of fully immunized participants (24.78%), and in Sundergarh district, most of the study participants (58.1%) were unimmunized. Interpretation & conclusions: This study found high seroprevalence against SARS-CoV-2 in the tribal population of Odisha. The vaccination coverage is at par with the general population, and efforts to address some knowledge gaps may be needed to improve the coverage in the future.

Trend in seroprevalence of SARS-CoV-2 (IgG antibody) among tribal-dominated population: Findings from Jharkhand, India.

Background & objectives: Serosurvey of COVID-19 provides a better estimation of people who have developed antibodies against the infection. Undertaking such a serosurvey in certain districts of India which are densely populated with prominent tribes can provide valuable information regarding seropravelance of SARS-CoV-2 antibodies among such indigenous populations. In this context, two rounds of population-based, cross-sectional serosurveys for SARS-CoV-2 IgG antibody were carried out in Jharkhand, a tribal-dominated State of India, to compare the seroprevalence of SARS-CoV-2 infection and to determine the associated demographic risk factors. Methods: The surveys were carried out in June 2020 and February 2021 in ten districts of the State of Jharkhand. Blood samples were collected from the residents of the selected districts by random sampling and tested for anti-SARS-CoV-2 antibodies using an automated chemiluminescence immunoassay platform. A total of 4761 and 3855 eligible participants were included in round 1 and round 2, respectively. Results: The age- and gender-standardized seroprevalence for COVID-19 during round 1 was 0.54 per cent (0.36-0.80) that increased to 41.69 per cent (40.16-43.22) during round 2 with a gap of eight months in between. The seropositivity among male and female participants was 0.73 and 0.45 per cent, respectively, during the first round and 51.35 and 33.70 per cent, respectively, during the second round. During the first round, 17.37 per cent of the participants were tribal with seropositivity of 0.24 per cent (0.02-0.87), and during the second round, 21.14 per cent were tribal with seropositivity of 39.14 per cent (35.77-42.59). Compared to tribal group, non-tribal participants had an adjusted odds of 1.24 (95% confidence interval=1.04-1.48) for SARS-CoV-2 seropositivity. Interpretation & conclusions: COVID-19 seroprevalence was found to be low during the first round (0.54%) of the survey, possibly due to the travel restrictions during lockdown better adherence to social distancing and wearing of face masks among the people. Understanding the dynamics of SARS-CoV-2 transmission and the susceptibility to infection at the individual as well as community level will inform decision and help policy makers to design and implement effective public health strategies to mitigate the pandemic in this State.

Dynamicity and persistence of severe acute respiratory syndrome coronavirus-2 antibody response after double dose and the third dose with BBV-152 and AZD1222 vaccines: A prospective, longitudinal cohort study.

Introduction: Vaccines are available worldwide to combat coronavirus disease-19 (COVID-19). However, the long-term kinetics of the vaccine-induced antibodies against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have not been sufficiently evaluated. This study was performed to investigate the persistence and dynamicity of BBV-152 (Covaxin)- and AZD1222 (Covishield)-induced immunoglobulin-G (IgG) antibodies over the year and neutralizing antibodies' status after 1-month of booster dose. Materials and methods: This 52-week longitudinal cohort study documented antibody persistence and neutralizing antibodies status among 304 healthcare workers (HCWs) from six hospitals and research facilities in Odisha, enrolled during January 2021 and continued till March 2022. IgG antibodies against spike receptor-binding domain (RBD) of SARS-CoV-2 were quantified in an automated chemiluminescence immune assay-based (CLIA) platform and a surrogate virus neutralization test (sVNT) was performed by enzyme-linked immunosorbent assay (ELISA). Results: Among these 304 HCWs vaccinated with double doses, 154 HCWs (50.66%) were Covaxin recipients and the remaining 150 (49.34%) were Covishield recipients. During the follow-ups for seven times, a total of 114 participants were identified as vaccine breakthrough cases. In 190 non-infected HCWs, the median antibody titer was significantly waned from DD2 to DD10, both for Covaxin (231.8 vs. 42.7 AU/ml) and Covishield (1,884.6 vs. 369.2 AU/ml). No statistically significant differences in antibody titers were observed based on age, gender, comorbidities, and blood groups. The median inhibition activity of sVNT increased from 23.8 to 91.3% for Covaxin booster recipients and from 41.2 to 96.0% for Covishield booster recipients. Among 146 booster dose recipients, 48 were breakthrough cases after booster and all were contracted by the omicron variant. Conclusion: This year-long follow-up study found a 7- and 5-fold antibody waning in Covaxin and Covishield recipients, respectively, without any breakthrough infection history. However, individuals with booster breakthrough had mild symptoms and did not require hospital admission. The data also indicate the possible escape of omicron variants despite the presence of vaccine-induced neutralizing antibodies.

Temporal dynamics of oropharyngeal microbiome among SARS-CoV-2 patients reveals continued dysbiosis even after Viral Clearance.

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic has posed multiple challenges to global public health. Clinical features and sequela of SARS-CoV-2 infection include long-term and short-term complications often clinically indistinguishable from bacterial sepsis and acute lung infection. Post-hoc studies of previous SARS outbreaks postulate secondary bacterial infections with microbial dysbiosis. Oral microbial dysbiosis, particularly the altered proportion of Firmicutes and Proteobacteria, observed in other respiratory virus infection, like influenza, has shown to be associated with increased morbidity and mortality. Oropharynx and lung share similar kinds of bacterial species. We hypothesized that alteration in the Human Oropharyngeal Microbiome in SARS-CoV-2 patients can be a clinical indicator of bacterial infection related complications. We made a longitudinal comparison of oropharyngeal microbiome of 20 SARS-CoV-2 patients over a period of 30 days; at three time points, with a 15 days interval; contrasting them with a matched group of 10 healthy controls. Present observation indicates that posterior segment of the oropharyngeal microbiome is a key reservoir for bacteria causing pneumonia and chronic lung infection on SARS-CoV-2 infection. Oropharyngeal microbiome is indeed altered and its α-diversity decreases, indicating reduced stability, in all SARS-CoV-2 positive individuals right at Day-1; i.e. within ~24 h of post clinical diagnosis. The dysbiosis persists long-term (30 days) irrespective of viral clearance and/or administration of antibiotics. There is a severe depletion of commensal bacteria phyla like Firmicutes among the patients and that depletion is compensated by higher proportion of bacteria associated with sepsis and severe lung infection from phyla Proteobacteria. We also found elevated proportions of certain genus that have previously been shown to be causal for lung pneumonia in studies of model organisms and human autopsies' including Stenotrophomonas, Acenetobactor, Enterobactor, Klebsiella and Chryseobacterium that were to be elevated among the cases. We also show that responses to the antibiotics (Azithromycin and Doxycycline) are not uniform for all individuals.

Dynamicity and persistence of severe acute respiratory syndrome coronavirus-2 antibody response after double dose and the third dose with BBV-152 and AZD1222 vaccines: A prospective, longitudinal cohort study

Introduction Vaccines are available worldwide to combat coronavirus disease-19 (COVID-19). However, the long-term kinetics of the vaccine-induced antibodies against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have not been sufficiently evaluated. This study was performed to investigate the persistence and dynamicity of BBV-152 (Covaxin)- and AZD1222 (Covishield)-induced immunoglobulin-G (IgG) antibodies over the year and neutralizing antibodies’ status after 1-month of booster dose. Materials and methods This 52-week longitudinal cohort study documented antibody persistence and neutralizing antibodies status among 304 healthcare workers (HCWs) from six hospitals and research facilities in Odisha, enrolled during January 2021 and continued till March 2022. IgG antibodies against spike receptor-binding domain (RBD) of SARS-CoV-2 were quantified in an automated chemiluminescence immune assay-based (CLIA) platform and a surrogate virus neutralization test (sVNT) was performed by enzyme-linked immunosorbent assay (ELISA). Results Among these 304 HCWs vaccinated with double doses, 154 HCWs (50.66%) were Covaxin recipients and the remaining 150 (49.34%) were Covishield recipients. During the follow-ups for seven times, a total of 114 participants were identified as vaccine breakthrough cases. In 190 non-infected HCWs, the median antibody titer was significantly waned from DD2 to DD10, both for Covaxin (231.8 vs. 42.7 AU/ml) and Covishield (1,884.6 vs. 369.2 AU/ml). No statistically significant differences in antibody titers were observed based on age, gender, comorbidities, and blood groups. The median inhibition activity of sVNT increased from 23.8 to 91.3% for Covaxin booster recipients and from 41.2 to 96.0% for Covishield booster recipients. Among 146 booster dose recipients, 48 were breakthrough cases after booster and all were contracted by the omicron variant. Conclusion This year-long follow-up study found a 7- and 5-fold antibody waning in Covaxin and Covishield recipients, respectively, without any breakthrough infection history. However, individuals with booster breakthrough had mild symptoms and did not require hospital admission. The data also indicate the possible escape of omicron variants despite the presence of vaccine-induced neutralizing antibodies.

Persistence of Antibodies Against Spike Glycoprotein of SARS-CoV-2 in Healthcare Workers Post Double Dose of BBV-152 and AZD1222 Vaccines.

Purpose: We investigated the persistence of the vaccine-induced immunoglobulin G (IgG) antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among healthcare workers (HCWs) in Odisha who received a complete dose of either Covaxin or Covishield vaccine. Methods: This 24-week longitudinal cohort study was conducted from January to July 2021 with participants from 6 healthcare and research facilities of Odisha to understand the dynamicity of the vaccine-induced IgG antibodies against SARS-CoV-2 after the complete dose of vaccines. Results: Serum samples were collected from 614 participants during each follow-up and were tested in two chemiluminescent microparticle immunoassay (CLIA)-based platforms to detect SARS-CoV-2 antibodies both qualitatively and quantitatively. Among these participants, 308 (50.2%) participants were Covishield recipients and the rest 306 (49.8%) participants took Covaxin. A total of 81 breakthrough cases were recorded and the rest 533 HCWs without any history of postvaccination infection showed significant antibody waning either from T3 (Covaxin recipient) or T4 (Covishield recipient). The production of vaccine-induced IgG antibodies is significantly higher (p < 0.001) in Covishield compared with Covaxin. Covishield recipients produced higher median anti-S IgG titer than Covaxin. No statistically significant differences in antibody titers were observed based on age, gender, comorbidities, and blood groups. Conclusion: This 6-month follow-up study documents a 2-fold and 4-fold decrease in spike antibody titer among Covishield and Covaxin recipients, respectively. The clinical implications of antibody waning after vaccination are not well understood. It also highlights the need for further data to understand the long-term persistence of vaccine-induced antibody and threshold antibody titer required for protection against reinfection.

SARS-CoV-2 IgG antibody responses in rt-PCR-positive cases: first report from India.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses remain poorly understood and the clinical utility of serological testing is still unclear. AIM: To understand the relationship between the antibody response to SARS-CoV-2 infection and the demographics and cycle threshold (C t) values of confirmed RT-PCR patients. METHODOLOGY: A total of 384 serum samples were collected from individuals between 4-6 weeks after confirmed SARS-CoV-2 infection and tested for the development of immunoglobulin class G (IgG) against SARS-CoV-2. The C t values, age, gender and symptoms of the patients were correlated with the development of antibodies. RESULTS: IgG positivity was found to be 80.2 % (95 % CI, 76.2-84.2). Positivity increased with a decrease in the C t value, with the highest (87.6 %) positivity observed in individuals with C t values <20. The mean (±sd) C t values for IgG positives and negatives were 23.34 (±6.09) and 26.72 (±7.031), respectively. No significant difference was found for demographic characteristics such as age and sex and symptoms and antibody response. The current study is the first of its kind wherein we have assessed the correlation of the RT-PCR C t with the development of IgG against SARS-CoV-2. CONCLUSION: Although C t values might not have any relation with the development of symptoms, they are associated with the antibody response among SARS-CoV-2-infected individuals.

COVID-19 in children in Odisha state, India: a retrospective review.

We retrospectively analysed the swab samples tested for COVID-19 from 7 March 2020 to 17 August 2021 at the Indian Council of Medical Research-Regional Medical Research Centre, Bhubaneswar, Odisha. 553 763 nasopharyngeal swabs were collected from individuals suspected with COVID-19 in Odisha state. 75 190 (13.6%) samples were positive by reverse transcription-PCR. There were 5988 (8%) cases in children and young people under 18 years old. Odisha reported 996 153 COVID-19 cases which resulted in 6985 deaths in adults and 36 in children and young people under 18 years old.

Breakthrough SARS-CoV-2 infections among BBV-152 (COVAXIN®) and AZD1222 (COVISHIELDTM ) recipients: Report from the eastern state of India.

In this study, we attempted to record the breakthrough cases reported through passive and voluntary reporting at various healthcare facilities from different districts of Odisha, their clinical presentation, requirement of hospitalization postinfection, and antibody titer against spike antigen. Nasopharyngeal swab and serum samples alongwith demographic, clinical presentation and requirement of hospitalization postinfection were collected from vaccinated individuals through passive and voluntary reporting to various healthcare facilities of Odisha state to detect the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus infection and quantitative estimation of antibody titers. A total of 274 samples were found to be positive after 14 days of receiving complete doses of the vaccines. More than 83.2% of the individuals were found to be symptomatic with 9.9% of those required hospitalization. The seropositivity in individuals receiving Covishield (96.7%) was significantly higher than in Covaxin (77.1%). Hospitalized patients were having less median antibody titers than individuals in home isolation. The median age for breakthrough infection among the referred cases was 47.0 years (interquartile range [IQR]: 28.0) with a significantly older age group among Covishield recipients. The median spike receptor binding domain IgG titer values for Covaxin and Covishield recipients were 213.5 AU/ml (IQR: 537.5) and 647.5 AU/ml (IQR: 1645.1), respectively. The results reported here highlight the need for systematic data capture for the breakthrough infections to monitor the emergence of any vaccine escape variants and to plan the next steps in the coronavirus disease-19 (COVID-19) vaccine development by understanding the link between clinical protection and measured immunity against SARS-CoV-2 infection.

IgG antibody response against nucleocapsid and spike protein post-SARS-CoV-2 infection.

OBJECTIVES: Coronavirus disease-19 (COVID-19) pandemic became the greatest public health challenge globally. Study of dynamicity and durability of naturally developed antibodies against SARS-CoV-2 are of great importance from an epidemiological viewpoint. METHODS: In this observational cohort study, we have followed up the 76 individuals who tested positive for SARS-CoV-2 infection by real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) for 16 weeks (post-enrolment) to record the periodic changes in titre, concentration, clinical growth and persistence of naturally developed SARS-CoV-2 antibodies. We collected serum samples from these individuals for 16 weeks with a frequency of weekly and fortnightly during each follow-up and tested them in two CLIA-based platforms (Abbott Architect i1000SR and Roche Cobas e411) for testing SARS-CoV-2 antibodies both qualitatively and quantitatively. RESULTS: We recorded the antibody magnitude of these individuals 10 times between September 2020 and February 2021. We found a waning of antibodies against nucleocapsid antigen protein but not a complete disappearance by the end of 16 weeks. Out of 76 cases, 30 cases (39.47%) became seronegative in qualitative assay, although all the sera samples (100%) remained positive when tested in quantitative assay. CONCLUSION: The lower persistence of anti-nucleocapsid SARS-CoV-2 antibody may not be the exact phenomenon as those cases were still seropositive against spike protein and help in neutralising the virus.

Pooled testing for SARS-CoV-2 infection in an automated high-throughput platform.

BACKGROUND: Active detection of SARS-CoV-2 infection through testing is elementary for the control of COVID-19 pandemic. The implementation of large-scale RT-PCR testing has led to a rise in the demand for testing kits whose availability is always a concern. OBJECTIVE: To find out the feasibility of pooled testing in a high-throughput platform. METHODOLOGY: Pooled testing was conducted in Roche cobas 6800 in 2 methods. Firstly, the simple two-stage testing algorithm was conducted for 1410 samples individually and then as pooled samples. Secondly, we evaluated the sensitivity of cobas 6800 for the detection of a single positive sample within a pool of negative samples. RESULTS: Implementing the five-sample Dorfman pooling to test 1410 samples, we identified 42 (2.9%) individual SARS-CoV-2-positive samples and 27 (9.5%) positive pool samples. The pooling strategy precisely identified all the positive samples. All individually negative samples were also accurately determined by pooling. There was 100% sensitivity of detecting positive samples in a pool of negative samples even up to 1:64 dilution. There was a threefold increase in total throughput in one-third of the cost per day. CONCLUSION: A high-throughput platform such as Cobas 6800 can effectively increase the testing capacity by twofold to threefold by adopting the pooled testing strategy for successful management of SARS-CoV-2 and helping in the containment of community transmission.

Seroprevalence of SARS-CoV-2 in Bhubaneswar, India: findings from three rounds of community surveys.

The study aims to estimate and compare the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence, the fraction of asymptomatic or subclinical infections in the population, determine the demographic risk factors and analyse the antibody development at different time points among adults in Bhubaneswar city, India. This was a serial three-round cross-sectional, community-based study where participants were selected from the residents of Bhubaneswar city using multi-stage random sampling. Blood samples were collected during household visits along with demographic and clinical data from every participant. Total anti-SARS-CoV-2 antibody present in serum was assessed using the electro-chemiluminescence immunoassay platform. Temporal comparisons of the community seroprevalence were performed against the detected number of cumulative cases, active cases, recoveries and deaths. A total of 3693 participants were enrolled in this study with a cumulative non-response rate of 18.33% in all the three rounds. The gender-weighted seroprevalence for the city in the first round was 1.55% (95% confidence interval (CI) 0.84-2.58), second round was 5.27% (95% CI 4.13-6.59) and in the third round was 49.04% (95% CI 46.39-51.68). In the first round, the seroprevalence was found to be highest in the elderly population, whereas the seroprevalence for the second and third phases was highest in the age group of 30-39 years. Seroprevalence showed an increasing trend over the three time periods, with the highest seropositivity rates among individuals sampled between 16 and 18 September 2020. By the third round, 93.93% of those who had previously been tested positive by real-time reverse transcription polymerase chain reaction had seroconversion and 46.57% of those who had been tested negative also showed seroconversion. Infection to case ratio during first round was 27.05, for second round and third round it was 5.62 and 17.91, respectively.

Serological surveys to inform SARS-CoV-2 epidemic curve: a cross-sectional study from Odisha, India.

This was a population based cross-sectional study carried out to estimate and compare the seroprevalence, hidden prevalence and determine the demographic risk factors associated with SARS-CoV-2 infection among adults in the three largest cities of Odisha, India, and ascertain the association with the progression of the epidemic. The survey carried out in August 2020 in the three largest cities of the state of Odisha, India. Blood samples were collected from the residents using random sampling methods and tested for anti- SARS CoV-2 antibodies using an automated CLIA platform. A total of 4146 participants from the 3 cities of Bhubaneswar (BBS), Berhampur (BAM) and Rourkela (RKL) participated. The female to male participation ratio was 5.9:10 across the three cities. The gender weighted seroprevalence across the three cities was 20.78% (95% CI 19.56-22.05%). While females reported a higher seroprevalence (22.8%) as compared to males (18.8%), there was no significant difference in seroprevalence across age groups. A majority of the seropositive participants were asymptomatic (90.49%). The case to infection ratio on the date of serosurvey was 1:6.6 in BBS, 1:61 in BAM and 1:29.8 in RKL. The study found a high seroprevalence against COVID-19 in urban Odisha as well as high numbers of asymptomatic infections. The epidemic curves had a correlation with the seroprevalence.

Saliva for diagnosis of SARS-CoV-2: First report from India.

There are very few studies in search of an alternate and convenient diagnostic tool which can substitute nasopharyngeal swab (NPS) specimen for detection of SARS-CoV-2. In the study we analyzed, the comparison and agreement between the feasibility of using the saliva in comparison to NPS for diagnosis of SARS-CoV-2. A total number of 74 patients were enrolled for this study. We analyzed and compared the NPS and saliva specimen collected within 48 h after the symptom onset. We carried out real-time quantitative polymerase chain reaction, gene sequencing for the detection and determination SARS-CoV-2 specific genes. Phylogenetic tree was constructed to establish the isolation of viral RNA from saliva. We used the Bland-Altman model to identify the agreement between two specimens. This study showed a lower cycle threshold (CT ) mean value for the detection of SARS-CoV-2 ORF1 gene (mean, 27.07; 95% confidence interval [CI], 25.62 to 28.52) in saliva methods than that of NPS (mean 28.24; 95% CI, 26.62 to 29.85) specimen although the difference is statistically nonsignificant (p > .05). Bland-Altman analysis produced relatively smaller bias and high agreement between these two clinical specimens. Phylogenetic analysis with the RdRp and S gene confirmed the presence of SARS-CoV-2 in the saliva samples. Saliva represented a promising tool in COVID-19 diagnosis and the collection method would reduce the exposure risk of frontline health workers which is one of the major concerns in primary healthcare settings.

Diagnostic accuracy comparison of three fully automated chemiluminescent immunoassay platforms for the detection of SARS-CoV-2 antibodies.

BACKGROUND: Serological test is an essential surveillance tool to track down the extensiveness of SARS-CoV-2 transmission and subsequently to move out from the enforced lockdown stage. OBJECTIVE: The study measures the diagnostic accuracy of three popular chemiluminescent immunoassay (CLIA) based automated platforms for the detection of anti-SARS-CoV-2 antibodies and compares their agreements. STUDY DESIGN: Serum samples of 594 COVID-19 positive patients and 100 samples from pre-COVID cases were tested by three CLIA based automated platforms: Abbott architect i2000SR, Roche cobas e411 and Yhlo iFlash 1800 and their diagnostic accuracy were compared by the area under the curves (AUC) value obtained from receiver operator characteristic (ROC) curves. Cohen's kappa statistic and McNemar's test were used to interpret the agreement between the platforms. RESULTS: All three platforms showed high specificity as claimed by the manufacturer. Sensitivity was calculated as 64.48 % (58.67-70.3) for Abbott, 80.48 % (76.62-84.34) for Roche and 76.94 % (72.65-81.23) for Yhlo. AUC was maximum for Roche (0.929). The Cohen's kappa value was determined in between 0.69-0.89 as the inter-rater agreements. CONCLUSION: The overall statistical analysis demonstrated cobas e411 as the diagnostically most accurate platform among the three.