Main Article Content
Abstract
BACKGROUND
Efficacy of COVID vaccines has been evaluated in various studies. The interim analysis from four randomized controlled trials in UK, Brazil, and south Africa regarding efficacy of two doses of the vaccine was found to be 70.4% (95·8% CI 54·8–80·6). There is a limited data on follow-up Ab titer post vaccination. Hence, the current study is first of its kind with the objective to determine vaccine long term efficacy and its determinants.
METHODS
Health Care Workers (HCW) from Apollo Multispeciality Hospitals, Kolkata who underwent Covishield vaccination from January 2021 to April 2021 were included in the study. Serological testing was done prior to first and second dose of vaccinations, and additionally around six months post second dose.
RESULTS
Between January 2021 to April 2021, 2032 HCW, with predominant age of less than 30 years (44.83%) and male gender (61.96%) undergoing Covishield vaccination were enrolled. Antibodies were detected in 953 (46.9%) individuals prior to first dose, 1449 out of 1495 (96.9%) remained positive prior to second dose and 465 out of 504 (92.3%) HCW after 6 months and remaining 39 (7.7%) either had lost or never had antibodies in their blood. The mean ± SD value of first, second and third antibodies were 2.35 ± 3.10, 10.46 ± 4.84 and 8.75 ± 4.88 respectively.
CONCLUSIONS
This study provides long observation period, covering the complete progress of the pandemic which provides a “real-life” picture of the antibody level dynamics over time, and after vaccination.
Keywords
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References
- WHO. WHO Director-General’s opening remarks at the media briefing on COVID-19-11 March 2020. Geneva, Switzerland: World Health Organization 2020.
- Changotra R, Rajput H, Rajput P, et al. Largest democracy in the world crippled by COVID-19: current perspective and experience from India. Environ Dev Sustain 2021;23(5):6623-41.
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- Kunal S, Sakthivel P, Gupta N, et al. Mix and match COVID-19 vaccines: potential benefit and perspective from India. Postgrad Med J 2021;2021:140648.
- Voysey M, Clemens SAC, Madhi SA. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. Lancet 2021;397(10269):99-111.
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- Folegatti PM, Ewer KJ, Aley PK, et al. Safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2: a preliminary report of a phase 1/2, single-blind, randomised controlled trial. Lancet 2020;396(10249):467-78.
- Wajnberg A, Amanat F, Firpo A, et al. Robust neutralizing antibodies to SARS-CoV-2 infection persist for months. Science 2020;370(6521):1227-30.
- GeurtsvanKessel CH, Okba NM, Igloi Z, et al. An evaluation of COVID-19 serological assays informs future diagnostics and exposure assessment. Nat Commun 2020;11(1):3436.
- Eyre DW, Lumley SF, Wei J, et al. Quantitative SARS-CoV-2 anti-spike responses to Pfizer-BioNTech and Oxford-AstraZeneca vaccines by previous infection status. Clin Microbiol Infect 2021;27(10):1516.e7-14.
- Voysey M, Clemens SAC, Madhi SA, et al. Single-dose administration and the influence of the timing of the booster dose on immunogenicity and efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine: a pooled analysis of four randomised trials. Lancet 2021;397(10277):881-91.
- Huang AT, Garcia-Carreras B, Hitchings MD, et al. A systematic review of antibody mediated immunity to coronaviruses: kinetics, correlates of protection, and association with severity. Nat Commun 2020;11(1):1-16.
- Den Hartog G, Vos ERA, van den Hoogen LL, et al. Persistence of antibodies to SARS-CoV-2 in relation to symptoms in a nationwide prospective study. Clin Infect Dis 2021;73(12):2155-62.
- Poon MM, Rybkina K, Kato Y, et al. SARS-CoV-2 infection generates tissue-localized immunological memory in humans. Sci Immunol 2021;6(65):eabl9105.
- Lumley SF, Wei J, O’Donnell D, et al. The duration, dynamics, and determinants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses in individual healthcare workers. Clin Infect Dis 2021;73(3):e699-709.
- Vanshylla K, Di Cristanziano V, Kleipass F, et al. Kinetics and correlates of the neutralizing antibody response to SARS-CoV-2 infection in humans. Cell Host Microbe 2021;29(6):917-29.
- Lange T, Dimitrov S, Bollinger T, et al. Sleep after vaccination boosts immunological memory. J Immunol. 2011;187(1):283–90.
- Spiegel K, Sheridan JF, Van Cauter E. Effect of sleep deprivation on response to immunizaton. JAMA 2002;288(12):1471-2.
- Lange T, Perras B, Fehm HL, et al. Sleep enhances the human antibody response to hepatitis A vaccination. Psychosom Med 2003;65(5):831-5.
References
WHO. WHO Director-General’s opening remarks at the media briefing on COVID-19-11 March 2020. Geneva, Switzerland: World Health Organization 2020.
Changotra R, Rajput H, Rajput P, et al. Largest democracy in the world crippled by COVID-19: current perspective and experience from India. Environ Dev Sustain 2021;23(5):6623-41.
WHO. Interim recommendations for use of the ChAdOx1-S [recombinant] vaccine against COVID-19 (AstraZeneca COVID-19 vaccine AZD1222 VaxzevriaTM, SII COVISHIELDTM). World Health Organization 2021.
Kunal S, Sakthivel P, Gupta N, et al. Mix and match COVID-19 vaccines: potential benefit and perspective from India. Postgrad Med J 2021;2021:140648.
Voysey M, Clemens SAC, Madhi SA. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. Lancet 2021;397(10269):99-111.
Pramod S, Govindan D, Ramasubramani P, et al. Effectiveness of Covishield vaccine in preventing Covid–19-A test–negative case–control study. medRxiv 2021: doi: 10.1016/j.vaccine.2022.02.014
Folegatti PM, Ewer KJ, Aley PK, et al. Safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2: a preliminary report of a phase 1/2, single-blind, randomised controlled trial. Lancet 2020;396(10249):467-78.
Wajnberg A, Amanat F, Firpo A, et al. Robust neutralizing antibodies to SARS-CoV-2 infection persist for months. Science 2020;370(6521):1227-30.
GeurtsvanKessel CH, Okba NM, Igloi Z, et al. An evaluation of COVID-19 serological assays informs future diagnostics and exposure assessment. Nat Commun 2020;11(1):3436.
Eyre DW, Lumley SF, Wei J, et al. Quantitative SARS-CoV-2 anti-spike responses to Pfizer-BioNTech and Oxford-AstraZeneca vaccines by previous infection status. Clin Microbiol Infect 2021;27(10):1516.e7-14.
Voysey M, Clemens SAC, Madhi SA, et al. Single-dose administration and the influence of the timing of the booster dose on immunogenicity and efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine: a pooled analysis of four randomised trials. Lancet 2021;397(10277):881-91.
Huang AT, Garcia-Carreras B, Hitchings MD, et al. A systematic review of antibody mediated immunity to coronaviruses: kinetics, correlates of protection, and association with severity. Nat Commun 2020;11(1):1-16.
Den Hartog G, Vos ERA, van den Hoogen LL, et al. Persistence of antibodies to SARS-CoV-2 in relation to symptoms in a nationwide prospective study. Clin Infect Dis 2021;73(12):2155-62.
Poon MM, Rybkina K, Kato Y, et al. SARS-CoV-2 infection generates tissue-localized immunological memory in humans. Sci Immunol 2021;6(65):eabl9105.
Lumley SF, Wei J, O’Donnell D, et al. The duration, dynamics, and determinants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses in individual healthcare workers. Clin Infect Dis 2021;73(3):e699-709.
Vanshylla K, Di Cristanziano V, Kleipass F, et al. Kinetics and correlates of the neutralizing antibody response to SARS-CoV-2 infection in humans. Cell Host Microbe 2021;29(6):917-29.
Lange T, Dimitrov S, Bollinger T, et al. Sleep after vaccination boosts immunological memory. J Immunol. 2011;187(1):283–90.
Spiegel K, Sheridan JF, Van Cauter E. Effect of sleep deprivation on response to immunizaton. JAMA 2002;288(12):1471-2.
Lange T, Perras B, Fehm HL, et al. Sleep enhances the human antibody response to hepatitis A vaccination. Psychosom Med 2003;65(5):831-5.