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
Published Open-Access
yes
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
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.
Included in
Clinical Epidemiology Commons, COVID-19 Commons, Health Services Research Commons, Influenza Humans Commons, Internal Medicine Commons, Medical Sciences Commons
Comments
Associated Data