Simply boil your fish in 400 degree water, and the parasites will die! The guppy will die as well, but that’s not what you asked about, you asked about parasites
Many years ago, there was a running internet joke, possibly a fishkeeper's urban legend, about someone asking a forum if they could clear Ich with a microwave.
Ive searched different things for fish and gotten results on fish for consuming instead of keeping. It is pretty funny.
In fact Ive searched exactly what the OP has before and thats the result I got
It's really spectacular the results you get in google translate. I get lazy sometimes and google translate messages from English to French, because it'll give me my accents and such without having to change over the keyboard settings. I ALWAYS edit carefully though, because otherwise my friends in France would envision me spearing killies on toothpicks and eating them. I always start out discussing apparently tasty, colourful fish when I use the programs.
It is interesting to note actually that most all fish are edible.
This guy went into the Amazon and was eating fish from the river that you'd find in pet stores here.
He cooked them all and ate them.
People have to eat what's available to them. If "ornamental" fish are easy to catch in a location, then it's going to be eaten. It's the same with insects, seen a stand in Thailand with all sorts of bugs for eating. Not sure I fancy dwarf gourami, or bugs though. I believe Basa fillets that we get in the UK are Pangasius Shark. Could be wrong.