Transmission event of SARS-CoV-2 delta variant reveals multiple vaccine breakthrough infections.

TitleTransmission event of SARS-CoV-2 delta variant reveals multiple vaccine breakthrough infections.
Publication TypeJournal Article
Year of Publication2021
AuthorsFarinholt, T, Doddapaneni, H, Qin, X, Menon, V, Meng, Q, Metcalf, G, Chao, H, Gingras, M-C, Avadhanula, V, Farinholt, P, Agrawal, C, Muzny, DM, Piedra, PA, Gibbs, RA, Petrosino, J
JournalBMC Med
Volume19
Issue1
Pagination255
Date Published2021 10 01
ISSN1741-7015
KeywordsBNT162 Vaccine, COVID-19, COVID-19 Vaccines, Humans, Immune Evasion, SARS-CoV-2
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.

DOI10.1186/s12916-021-02103-4
Alternate JournalBMC Med
PubMed ID34593004
PubMed Central IDPMC8483940
Grant ListU19 AI144297 / AI / NIAID NIH HHS / United States
1U19AI144297 / / national institute of allergy and infectious diseases /