TWiV reviews evidence that symptomatic adenovirus infection leads to thrombocytopenia, thrombosis, and production of anti-platelet factor 4 antibodies similar to the rare disorder seen after immunization with adenoviral vectored COVID-19 vaccines, and a monoclonal antibody isolated from a SARS survivor, following vaccination with a SARS-CoV-2 spike mRNA vaccine, that neutralizes a broad collection of ACE2-binding sarbecoviruses..

TWiV reviews the results of serum neutralization assays which show that a third vaccine dose restores neutralization of the Omicron variant, and interaction of platelet factor 4 with the adenovirus capsid, suggesting a mechanism for thrombosis with thrombocytopenia syndrome.