My card turned to be not readable on my Mac after I inserted it into a PC

I have been using my SanDisk Extrem 480G for my camera and I can read it on my mac laotop, however, after I interted it into a friend’s PC ( I did nothing after I interted it and the PC coudn’t recognize it), I connect the card to my mac laptop to get the footage just like I usually do, and the my mac says “the card is not readable” and there are three options: ignore, initialize, eject. 

Is there a way to fix it? The footage in the card is valuable to me!

Thanks

It could be infected by a virus. Try a full scan on that and see what it got. 

@hirsche wrote:

It could be infected by a virus.

Extremely doubtful.

A common problem. (Did you eject the disk from the pc before removing it?) You need to run a photo/file recovery program on your Mac. Launch the program first, then insert the stick or card. I use Prosoft Tools for this. They make several programs, I use Picture Rescue for photos. Most pc users do not understand the file directory can be corrupted very easily. That is probably what happened.