Transmission Event of SARS-CoV-2 Delta Variant Reveals Multiple Vaccine Breakthrough Infections

Authors

Timothy Farinholt
Harsha Doddapaneni
Xiang Qin
Vipin Menon
Qingchang Meng
Ginger Metcalf
Hsu Chao
Marie-Claude Gingras
Vasanthi Avadhanula
Paige Farinholt
Charu Agrawal
Donna M Muzny
Pedro A Piedra
Richard A Gibbs
Joseph Petrosino

Language

English

Publication Date

10-1-2021

Journal

BMC Medicine

DOI

10.1186/s12916-021-02103-4

PMID

34593004

PMCID

PMC8483940

PubMedCentral® Posted Date

10-1-2021

PubMedCentral® Full Text Version

Post-Print

Abstract

BACKGROUND: This study aims to identify the causative strain of SARS-CoV-2 in a cluster of vaccine breakthroughs. Vaccine breakthrough by a highly transmissible SARS-CoV-2 strain is a risk to global public health.

METHODS: Nasopharyngeal swabs from suspected vaccine breakthrough cases were tested for SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) by qPCR (quantitative polymerase chain reaction) for Wuhan-Hu1 and alpha variant. Positive samples were then sequenced by Swift Normalase Amplicon Panels to determine the causal variant. GATK (genome analysis toolkit) variants were filtered with allele fraction ≥80 and min read depth 30x.

RESULTS: Viral sequencing revealed an infection cluster of 6 vaccinated patients infected with the delta (B.1.617.2) SARS-CoV-2 variant. With no history of vaccine breakthrough, this suggests the delta variant may possess immune evasion in patients that received the Pfizer BNT162b2, Moderna mRNA-1273, and Covaxin BBV152.

CONCLUSIONS: Delta variant may pose the highest risk out of any currently circulating SARS-CoV-2 variants, with previously described increased transmissibility over alpha variant and now, possible vaccine breakthrough.

FUNDING: Parts of this work was supported by the National Institute of Allergy and Infectious Diseases (1U19AI144297) and Baylor College of Medicine internal funding.

Keywords

BNT162 Vaccine, COVID-19, COVID-19 Vaccines, Humans, Immune Evasion, SARS-CoV-2, SARS-CoV-2, Delta variant, B.1.617.2, COVID-19, Infectious disease

Published Open-Access

yes

Recommended Citation

Farinholt, Timothy; Doddapaneni, Harsha; Qin, Xiang; et al., "Transmission Event of SARS-CoV-2 Delta Variant Reveals Multiple Vaccine Breakthrough Infections" (2021). Faculty and Staff Publications. 1540.
https://digitalcommons.library.tmc.edu/baylor_docs/1540