Covid vaccine, ok to mix mRna even for third dose. “The ‘mix-and-match’ approach or heterologous vaccination with an mRna vaccine can be used both for the first doses and for the boosters”, according to the new recommendations of the EMA and the Ecdc. Several experts had already expressed themselves on the subject. “For the third dose” of the anti-Covid vaccine “only mRna vaccines are administered and there is no problem in combining these types of vaccines for the booster”, clarified the virologist Fabrizio Pregliasco, professor at the State University of Milan “There is no problem switching vaccines because they all target the ‘spike’ and many people have already been vaccinated with a heterologous combination of different vaccines. Pfizer or Moderna are both fine regardless of what you received during the first round.” had written on Twitter in the days of the immunologist of the Universi di Padova Antonella Viola.