DOI: http://dx.doi.org/10.18203/2349-3933.ijam20214520

Protection offered by COVID-19 vaccine against morbidity and mortality due to COVID-19 infection: a postvaccination cohort study

Arti Muley, Sona Mitra, Ashish Bavishi, Hema Bhojani, Geetika Patel, Dinesh Nakum, Sakshi Shah, Pratham Prajapati, Ayush Abraham, Parth Patel, Mit Patel, Stavan Padia, Preyasi Chaudhari, Aayushi Gadhvi, Gehna Patel, Jeel Dhapa, Shifa Gajdhar, Chitrali ., Nikunj Bhingadriya

Abstract


Background: Many vaccines have been developed, approved and administered against the COVID-19. Phase 2 and 3 trials have proved the safety and tolerability of these. This study was conducted to assess effect of the vaccines on morbidity and mortality due to postvaccination new COVID-19 infection.

Methods: This was an observational, retrospective cohort study. The patients admitted with COVID-19 from 1st April 2021 till 30th April 2021 who were willing to participate were included. All the patients were telephonically contacted post discharge and enquired regarding history of vaccination, events during hospitalization and outcome. The data so collected was analysed to compare the morbidity (oxygen requirement, need of ICU admission and need of BiPAP or invasive ventilation) and mortality between vaccinated and nonvaccinated COVID-19 patients and relation of time elapsed post vaccination with morbidity and mortality.

Results: Total 431 patients were included. There was significant difference between the two groups in terms of need for ICU admission (OR 0.503; CI 0.30-0.82, p=0.008) as well as requirement of BiPAP or invasive ventilation (OR 0.57; CI 0.33-0.98, p=0.05). Mortality was significantly less in the vaccinated group; OR 0.48 (0.24-0.95), p=0.04). Ten patients had received both doses. Only one required ICU while none of them required invasive ventilation and none expired.

Conclusions: COVID-19 vaccine gives significant protection against COVID-19 infection related ICU admission, need of mechanical ventilation and mortality even after single dose. Two doses of vaccine may afford better protection against the disease.


Keywords


COVID 19 vaccine, Morbidity, Mortality

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References


Walker PGT, Whittaker C, Watson OJ. The impact of COVID-19 and strategies for mitigation and suppression in low- and middle-income countries. Science. 2020;369:413-22.

Callaway E. The race for coronavirus vaccines: a graphical guide. Nature. 2020;580:576-7.

Krammer F. SARS-CoV-2 vaccines in development. Nature. 2020;586:516-27.

Corey L, Mascola JR, Fauci AS, Collins FS. A strategic approach to COVID-19 vaccine R&D. Science. 2020;368:948-50.

Graham BS. Rapid COVID-19 vaccine development. Science. 2020;368:945-6.

US Department of Health and Human Services: Food and Drug Administration. Development and licensure of vaccines to prevent COVID-19: guidance for industry. June, 2020. Available at: https://www.fda.gov/ media/139638/download. Accessed on 10 Jan. 20201.

WHO. R and D blueprint: an international randomized trial of candidate vaccines against COVID-19. Geneva: World Health Organization. 2020. Available at: https://www.who.int/publications/i/item/an-international-randomised-trial-of-candidate-vaccines-against-covid-19.

Zhang Y, Zeng G, Pan H. Safety, tolerability, and immunogenicity of an inactivated SARS-CoV-2 vaccine in healthy adults aged 18-59 years: a randomized, double-blind, placebo-controlled, phase 1/2 clinical trial. Lancet Infect Dis. 2021;21:181-92.

Maheshi N Ramasamy, Angela M Minassian, Katie J Ewer. Safety and immunogenicity of ChAdOx1 nCoV-19 vaccine administered in a prime-boost regimen in young and old adults (COV002): a single-blind, randomized, controlled, phase 2/3 trial. Lancet. 2020;396(10267):1979-93.

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 randomized controlled trials in Brazil, South Africa, and the UK. Lancet. 2021;397(10269):99-111.

Zhu FC, Guan XH, Li YH, Huang JY, Jiang T. Immunogenicity and safety of a recombinant adenovirus type-5-vectored COVID-19 vaccine in healthy adults aged 18 years or older: a randomised, double-blind, placebo-controlled, phase 2 trial. Lancet. 2020, 396, 479−488.

Ramasamy MN, Minassian AM, Ewer KJ. Safety and immunogenicity of ChAdOx1 nCoV-19 vaccine administered in a prime-boost regimen in young and old adults (COV002): a single-blind, randomised, controlled, phase 2/3 trial. Lancet 2020;396(10267):1979-93.