TWiV discusses the finding that the envelope (E) protein of SARS-CoV-2 is sensed by toll-like receptor 2 on cells, leading to the production of inflammatory cytokines that cause damage to cells and tissues in COVID-19.

TWiV revisits Brazil’s rejection of Sputnik vaccine, examines influenza transmission via the air from the nasal epithelium of ferrets, and a history of accidental releases of polioviruses and their relevance for eradication of poliomyelitis.

In COVID-19 clinical update #61, Daniel Griffin reviews a modeling of future hospitalizations and deaths by vaccination rates and non pharmaceutical intervention scenarios, performance evaluation of rapid antigen tests, children making up a growing share of new cases, antibody response to mRNA vaccine in solid organ transplant recipients, and outcomes in hospitalized patients treated with tocilizumab.

TWiV examines the claim by Brazil’s ANVISA that the Sputnik vaccine contains replication-competent adenovirus, and a role for the furin cleavage site in SARS-CoV-2 spike for efficient reproduction in the respiratory tract, evasion of antiviral IFITM proteins, and transmission in ferrets.

The TWiVmeisters discuss how copy-back defective viral genomes might modulate the clinical outcome of respiratory syncytial virus infection, and detection of antibodies to henipa- and filo-like viruses in Trinidad bats.

A TWiV trio explains a method for sequencing single genomes of SARS-CoV-2 and its use to explore in-host evolution drive by antibody responses, and incidence of cerebral venous thrombosis in COVID-19 patients and vaccine recipients.

In COVID-19 clinical update #59, Daniel Griffin discusses a front-line health care worker survey, pre-exposure seropositivity and subsequent infection in healthy young adults, fitted filtration efficiency of double masking, BinaxNow rapid in-home antigen test, postvaccination infections in a nursing facility, safety of mRNA vaccine in pregnant women, case control study of Bamlanivimab, no evidence for brain infection in patients with neurolgical symptoms, and mortality among US patients hospitalized with COVID-19.