ABSTRACT
Background: The plaque reduction neutralization test (PRNT) is the gold standard to detect the neutralizing capacity of serum antibodies. Neutralizing antibodies confer protection against further infection. The present study measured the antibody level against SARS-CoV-2 among laboratory-confirmed COVID-19 cases and evaluated whether the presence of anti-SARS-CoV-2 antibodies indicates virus neutralizing capacity. Methods: One hundred COVID-19 confirmed cases were recruited. Their sociodemographic details and history of COVID-19 vaccination, contact with positive COVID-19 cases, and symptoms were ascertained using a self-developed semi-structured interview schedule. Serum samples of the participants were collected within three months from the date of the positive report of COVID-19. The presence of anti-SARS-CoV-2 antibodies (IgA, IgG and IgM antibodies), receptor binding domain antibodies (anti-RBD), and neutralizing antibodies were measured. Findings: Almost all the participants had anti-SARS-CoV-2 antibodies (IgA, IgG and IgM) (99%) and anti-RBD IgG antibodies (97%). However, only 69% had neutralizing antibodies against SARS-CoV-2. Anti-RBD antibody levels were significantly higher among participants having neutralizing antibodies compared with those who did not. Interpretation: The present study highlights that the presence of antibodies against SARS-CoV-2, or the presence of anti-RBD antibodies does not necessarily imply the presence of neutralizing antibodies.
ABSTRACT
OBJECTIVES: India introduced BBV152/Covaxin and AZD1222/Covishield vaccines in January 2021. We estimated the effectiveness of these vaccines against severe COVID-19 among individuals aged ≥45 years. METHODS: We did a multi-centric, hospital-based, case-control study between May and July 2021. Cases were severe COVID-19 patients, and controls were COVID-19 negative individuals from 11 hospitals. Vaccine effectiveness (VE) was estimated for complete (2 doses ≥ 14 days) and partial (1 dose ≥ 21 days) vaccination; interval between two vaccine doses and vaccination against the Delta variant. We used the random effects logistic regression model to calculate the adjusted odds ratios (aOR) with a 95% confidence interval (CI) after adjusting for relevant known confounders. RESULTS: We enrolled 1143 cases and 2541 control patients. The VE of complete vaccination was 85% (95% CI: 79-89%) with AZD1222/Covishield and 71% (95% CI: 57-81%) with BBV152/Covaxin. The VE was highest for 6-8 weeks between two doses of AZD1222/Covishield (94%, 95% CI: 86-97%) and BBV152/Covaxin (93%, 95% CI: 34-99%). The VE estimates were similar against the Delta strain and sub-lineages. CONCLUSION: BBV152/Covaxin and AZD1222/Covishield were effective against severe COVID-19 among the Indian population during the period of dominance of the highly transmissible Delta variant in the second wave of the pandemic. An escalation of two-dose coverage with COVID-19 vaccines is critical to reduce severe COVID-19 and further mitigate the pandemic in the country.
Subject(s)
COVID-19 , Influenza Vaccines , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , Case-Control Studies , ChAdOx1 nCoV-19 , Hospitals , Humans , SARS-CoV-2ABSTRACT
Background: Estimating seroepidemiolgical prevalence of SARS-CoV-2 antibody is an essential public health strategy. There is insufficient evidence of prevalence among those belonging to young age population in India. Objective: To compare the SARS-CoV-2 seropositivity rate between children and adults in selected sites from India. Materials and Methods: This was a multicentric population-based seroepidemiological study conducted in selected urban and rural areas of five sites selected from four states (Delhi, Odisha, Uttar Pradesh, Tripura) of India. Participants aged ≥1 year were included from different clusters of each area. Total serum antibody against SARS-CoV-2 virus was assessed qualitatively by using a standard enzyme-linked immunosorbent assay (ELISA) kit. Results: Data collection period was from 15 March 2021 to 10 June 2021. Total available data was of 4509 participants, of whom 700 were <18 years of age and 3809 were ≥18 years of age. The site-wise number of available data among those aged 2-17 years was 92, 189, 165, 146 and 108 for the sites of Delhi urban, Delhi rural, Bhubaneswar rural, Gorakhpur rural and Agartala rural area, respectively. The seroprevalence was 55.7% in the <18 years age group and 63.5% in the ≥18 years age group. The prevalence among female children was 58% and among male children was 53%. Conclusion: SARS-CoV-2 seropositivity rate among children was high and comparable to that of the adult population. Hence, it is unlikely that any future third wave by prevailing SARS-CoV-2 variant would disproportionately infect children 2 years or older.
ABSTRACT
Background: About 10% of patients with type 2 diabetes mellitus at the time of diagnosis have more than one risk factor for developing foot ulceration, and it increases to 15% in a lifetime. The risk of development of Diabetic foot ulcers/gangrene can be prevented by the patient's self-foot care practice at home. The present study aimed to determine the prevalence of awareness of self-foot care practice among diabetic patients in a rural setting. The study also aimed to identify the factors preventing dry or wet diabetic gangrene development and subsequent amputation. Methods: A hospital-based cross-sectional study was carried out among 1687 people with diabetes mellitus (DM) who attended orthopedic and diabetic OPD in a tertiary care hospital in Kamrup, Assam, India. An appropriate self-explanatory questionnaire about knowledge of self-foot care practice was given to all study participants. Foot examination was performed by authors participated in the study on all patients. The observations and results were categorized according to the International Diabetes Federation foot risk categories. Results: Of 1687 patients included in this study, 298 (17.7%) had foot ulcers of various grades, 164 (9.76%) had peripheral vascular disease, and 484 (28.7%), had peripheral neuropathy of different grades. After multivariate analysis, patients on insulin and combination therapy and peripheral neuropathy were significantly associated with the presence of foot ulcers. The mean knowledge score was as low as 9.7 ± 4.8 out of a total score of 23. Low awareness and knowledge were associated with low mean scores due to a lack of formal education (8.3 ± 6.1). Among the 1687 patients, only 381 (22.5%) are aware and have some knowledge about self-foot care, and 686 (40.6%) had their feet examined by a doctor only once since their initial diagnosis. The incidence of development of diabetic-related complications was significantly low in those who know about foot self-care as well as those whose feet had been inspected by a physician at least once. Conclusion: The incidence of development of diabetic-related complications was significantly low in those who know about foot self-care as well as those whose feet had been examined by a physician of family doctors at least once. There is a need to educate all patients of diabetes about self-foot care. It is prudent to establish an integrated foot care services within primary care centers and in the diabetic clinic to identify feet at risk, institute early preventive measures, and provide continuous foot care education through images videos on WhatsApp to patients and primary health care givers.