How to bring an effect like this through particle simulation?

This is an image being updated in render viewport, while the actual render is just small particles with yellow emission. Unfortunately, I don’t have an image of it.

If you look closer
It looks like fog & smoke, along with particles. And the particle seems to be leaving a trail of smoke behind and around it as it travels.

How can this effect be achieved?
Through motion blur? Or is there a different way?

Render Engine: Cycles

This looks like a point density effect. I know nothing about them. Geometry nodes stuff.