A systematic review of effectiveness of BNT162b2 mRNA and ChAdOx1 adenoviral vector COVID-19 vaccines in the general population

Abstract

Background High effectiveness of COVID-19 vaccines is essential for the pandemic control. This study systematically reviewed available evidence on effectiveness of ChAdOx1 and BNT162b2 vaccines in the general population, for improved vaccine policies and strategies. Main body of the abstract Using several keywords, a search of Scopus, PubMed, Google scholar and Hinari databases was conducted from December 1, 2020 to June 9, 2021. Eligible studies comprising original studies reporting effectiveness of the vaccines, were included following PRISMA guidelines. Individual studies were assessed for quality using National Heart, Lung and Blood Institute quality assessment tool. A total of 1766 titles were retrieved and 11 were included, out of which only 5 were peer-reviewed. Although data availability was limited, studies suggest equivalent effectiveness of BNT162b2 and ChAdOx1 COVID-19 vaccine against SARS-CoV-2 infection and COVID-19 related morbidity and mortality. Vaccine effectiveness increased steadily to about 35 days, with an enhanced effectiveness following the second dose. Short conclusion BNT162 and ChAdOx1 vaccines were associated with equivalent and high effectiveness which increased with time and a second dose in the general population. This encourages continued practice of other preventive measures, particularly during the first week of vaccination, and reinforces the need for a second dose.

COVID-19 Vaccine Rollouts and the Reproduction of Urban Spatial Inequality: Disparities Within Large US Cities in March and April 2021 by Racial/Ethnic and Socioeconomic Composition

“…[1] Vaccination curbed viral infection and transmission and reduced illness, hospitalization, and death from COVID-19. [2,3,4,5,6,7,8] Vaccines were free countrywide regardless of health insurance coverage. Eligibility progressed in stages per state and local policy.…”

COVID-19 Vaccine Effectiveness: A Review of the First 6 Months of COVID-19 Vaccine Availability (1 January–30 June 2021)

“…Of the 23 preprints initially identified, 12 were published prior to submission of this article, and in only a few instances were minor updates to the VE results required. While other VE reviews have been published [ 10 , 11 , 12 , 13 , 14 ], our review was unique in that we (1) provided VE results for the first 6 months of global vaccine use and for only fully vaccinated participants, (2) examined VE for three population groups separately, and (3) plotted VE results to allow for direct comparison across disease presentation and disease severity categories by vaccine and by days after full vaccination. For a global population that was immunologically naïve to SARS-CoV-2, our focus on VE among fully vaccinated persons aged 16 years and older is valuable because it provides a baseline to compare the effectiveness of full vaccination in various populations around the world without having to factor in the influence of waning immunity [ 68 , 69 ], novel variants [ 70 ], or subsequent vaccine doses.…”

“…We conducted a review of published (i.e., peer-reviewed) SARS-CoV-2 VE articles, supplemented by preprints posted on preprint servers and reports published on websites of public health agencies during the first 6 months of COVID-19 vaccine availability. While other VE reviews have been published [ 10 , 11 , 12 , 13 , 14 ], our review is unique in that we (1) provided VE results for the first 6 months of global vaccine use and for only fully vaccinated participants, (2) examined VE for three population groups separately, and (3) plotted VE results to allow for direct comparison across disease presentation and disease severity categories by vaccine and by days after full vaccination.…”

Immunogenicity and clinical features relating to BNT162b2 messenger RNA COVID-19 vaccine, Ad26.COV2.S and ChAdOx1 adenoviral vector COVID-19 vaccines: a systematic review of non-interventional studies

“…Similarly, the mRNA 1273 vaccine was also associated to a familial thrombocytopenia flare-up in a 36-year-old female [ 31 ]. However, high COVID-19 vaccines effectiveness has been previously reported in the general population [ 32 ] and associated risks appear to outweigh potential risks.…”