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

BMC Medicine

Pedro A. Piedra¹  Timothy Farinholt¹  Joseph Petrosino¹  Vasanthi Avadhanula¹  Paige Farinholt²  Charu Agrawal²  Xiang Qin³  Qingchang Meng³  Richard A. Gibbs³  Ginger Metcalf³  Hsu Chao³  Harsha Doddapaneni³  Vipin Menon³  Marie-Claude Gingras³  Donna M. Muzny³ 

[1] Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA;Department of Medicine, Baylor College of Medicine, Houston, TX, USA;Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA;Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA;

关键词: SARS-CoV-2;    Delta variant;    B.1.617.2;    COVID-19;    Infectious disease;   

DOI  :  10.1186/s12916-021-02103-4

来源: Springer

【 摘 要 】

BackgroundThis 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.MethodsNasopharyngeal 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.ResultsViral 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.ConclusionsDelta 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.FundingParts of this work was supported by the National Institute of Allergy and Infectious Diseases (1U19AI144297) and Baylor College of Medicine internal funding.

【 授权许可】

CC BY