CONCORD (CBS SF) — A Costco customer in Concord posted video of what they say was a parasite squirming around inside a package of salmon from the store.

The video was posted to Facebook three days ago, after the customer saw what he called a “living parasite” in the first package of fish he picked up.

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A Costco employee said the parasite-looking animals are not uncommon, and are typically roundworms.

Shoppers in the market for fresh fish can expect that they may be part of the package deal.

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Kenny Kim is a caterer with four decades of experience, and says it isn’t anything unusual.

“All the fish have a little worm in them for sure, most of them, but you have to cook the fish, and then it’s okay,” Kim said.

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