Is it permissible to leave a gap between worshipers in congregational prayer to prevent an epidemic, and is that considered an innovation (bid‘ah)?

There is no harm in worshippers spacing themselves out in the rows to prevent the transmission of infection, and this is preferable to abandoning the establishment of Friday prayers and congregational prayers altogether. It is not permissible to abandon the establishment of Friday prayers and congregational prayers as long as spacing out is sufficient to repel the danger of the epidemic. This falls under the category of dispensation and exception to ward off harm.