Salmon, being a fresh water fish, often carry parasites. When a good sushi maker prepares salmon sushi (raw), he must carefully examine each salmon fillet for parasites. Usually, Japanese are reluctant to eat salmon sashimi or sushi for this reason.
I believe what you are seeing, is a parasite from the raw salmon. If the salmon is well cooked, the parasite will be killed and it is safe to eat. However, anything that touches raw salmon {such as your dish) is potentially contaminated with these parasites. Please be careful about washing your hands, dishes, etc.
Other fresh water fish (e.g. catfish. etc) also have a possibility of these parasites, and must also be eaten well cooked. Hopefully you also know about the risk of parasites in pork.
As long as you are careful about cleanliness of preparation, and make sure you cook fresh water fish, pork, etc. well, you should be able to kill all the parasites that come with the fish or pork.
ETA: +1 on previous post. You are GTG just make sure you maintain good hygiene, and cook the salmon well.