A corrupted JPEG file will not normally damage other JPEGs in the same folder. Each image is a separate file. The bigger risk is the faulty card or software crashing while reading bad files.

To check the files that seem OK, use an image-integrity or batch-processing tool that will read every file and report errors. A practical approach is to batch-open or convert all images with a tool such as ImageMagick; files that fail to decode or convert are likely damaged.

If you still have the card, try copying the files again to a different folder rather than overwriting your first copy. Sometimes a file that failed once may copy successfully on another attempt, and keeping separate copies lets you compare results.

To minimize further loss:

• stop using the faulty SD card immediately
• make multiple copies of what you can recover
• use software that verifies files as it copies or processes them
• if one program crashes on bad files, try a different one

In short: damaged JPEGs won’t infect good ones, but you should verify all files with a batch read/convert tool and avoid any further use of the bad card.