Animating Red Blood Cells for VR

Hiya guys,
I need some advice. I am wanting to animate a number of gameobj (red&white blood cells + platelets) probably 30-40 in number. I am wanting to animate them along a path, I'm thinking a circle, where only part of the animation is ever visible to the user. I need them to remain alone standing gameobj as the user has to be able to interact with the physics properties when the animation is suspended (aka time is stopped). I don't know what the best route is in terms of performance. I looked at particle systems but it didn't seem appropriate as i need the game objects to all be interactable with?
a) animate a parent object
b) animate the blood cell in 3Ds max and bring into unity with it's own animation
c) solution I have not considered yet?

Many thanks in advance, any tips or routes to research would be great
Attached my storyboard for the scene, maybe helps visualize what I'm trying to achieve.

 

Hi,

How about pooling some individual game objects, each starting at a slightly random position somewhere behind the player, then following a path to where they loops around and starts all over again behind the player?

 

@artfish, I think maybe I found a solution
Thank you