claim: mva vector vaccines enhance sars cov-2 replication in upper and lower respiratory tracts of transgenic mice and prevent lethal disease.
evidence_1: in a transgenic mouse model, one or two injections of recombinant mvas that express modified forms of s inhibited cov-2 replication in the upper and lower respiratory tracts and prevented severe disease.", "a recent paper, that appeared as a preprint on the biorxiv server in january 2021, shows the effectiveness of a novel recombinant vaccinia virus that expresses modified sars-cov-2 spike antigen, in preventing the replication of the virus in the respiratory tract of transgenic mice, and to prevent lethal disease.", 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  "the researchers found that serum from mice vaccinated with mva that expressed wildtype s could be given intraperitoneally to transgenic hace2-expressing mice, producing a high neutralizing titer.", "weight loss and lethality following intranasal infection of transgenic hace2 mice with cov-2 was prevented by one or two immunizations with rmvas or by passive transfer of serum from vaccinated mice.")