Find Specific Value (Zeros) in .csv Files

I'm using the following to error-check directories below the current location to find files with a "0" value on a single line. The grep string I'm using finds all the zeros but I need to find any files with a single "0" on a line in files ending with SPD-daily.csv. I'm using this - grep -R --include "*SPD-daily.csv" 0 ./ and I get just about everything with a 0 in it. Thanks,