Clusters of SARS-CoV-2 Lineage B.1.1.7 Infection after Vaccination with Adenovirus-Vectored and Inactivated Vaccines

Abstract

A SARS-CoV-2 B.1.1.7 variant of concern (VOC) has been associated with increased transmissibility, hospitalization, and mortality. This study aimed to explore the factors associated with B.1.1.7 VOC infection in the context of vaccination. On March 2021, we detected SARS-CoV-2 RNA in nasopharyngeal samples from 14 of 22 individuals vaccinated with a single-dose of ChAdOx1 (outbreak A, n = 26), and 22 of 42 of individuals with two doses of the CoronaVac vaccine (outbreak B, n = 52) for breakthrough infection rates for ChAdOx1 of 63.6% and 52.4% for CoronaVac. The outbreaks were caused by two independent clusters of the B.1.1.7 VOC. The serum of PCR-positive symptomatic SARS-CoV-2-infected individuals had ~1.8–3.4-fold more neutralizing capacity against B.1.1.7 compared to the serum of asymptomatic individuals. These data based on exploratory analysis suggest that the B.1.1.7 variant can infect individuals partially immunized with a single dose of an adenovirus-vectored vaccine or fully immunized with two doses of an inactivated vaccine, although the vaccines were able to reduce the risk of severe disease and death caused by this VOC, even in the elderly.

A global epidemiological analysis of COVID-19 vaccine types and clinical outcomes

“…These observations persisted after adjustment for country-specific population size, age structure, and GDP distributions, as well as time-varying nonpharmaceutical interventions measured with the Stringency Index, and the dominant circulating SARS-CoV-2 variants. These large-scale epidemiological observations from geographically diverse countries place into a real-world context the existing data from clinical trials and ex vivo functional assays, which suggest that IVV does not confer as robust and durable clinical protection against SARS-CoV-2 as do genetic vaccines, particularly mRNAbased COVID-19 vaccines (Chen et al, 2021, Cheng et al, 2021, de Souza et al, 2021, Earle et al, 2021, Fernandez et al, 2022, Rotshild et al, 2021.…”

“…On the other hand, IVV are protein-based vaccines purified from chemically inactivated whole viruses that contain spike proteins in both pre-and post-fusion conformations that may impact effectiveness (Heinz and Stiasny, 2021). Antibodies against IVV may wane rapidly (Azak et al, 2021, Saure et al, 2022, especially in the elderly with immune senescence (Karamese and Tutuncu, 2022), and may have significantly reduced neutralization potency against specific SARS-CoV-2 variants of concern (Chen et al, 2021, de Souza et al, 2021, Fernandez et al, 2022.…”

Characteristics of COVID-19 Breakthrough Infections among Vaccinated Individuals and Associated Risk Factors: A Systematic Review

“…The N501Y mutation predominantly seen in the studies yielded by our review also lowers the neutralization capacity of the vaccines [ 25 , 69 ]. Infections with the N501Y mutation in the Alpha variant led to low neutralizing antibodies against the AZD1222 vaccine compared to non-Alpha variants [ 14 ].…”

SARS-CoV-2’s Variants of Concern: A Brief Characterization

“…In Brazil, the effectiveness of ChAdOx1 and CoronaVac/Sinovac was evaluated in two outbreaks of the alpha variant, in a convent and a Long Term Care Facility for the elderly. They observed that vaccination did not prevent people from becoming infected, but there was a reduction in the number of deaths, symptoms and severe cases of the disease, even in this population whose average age was around 77 years, with 1 dose of ChAdOx1 or two from CoronaVac/Sinovac ( 29 ).…”