So sorry for the late reply!
There's definitely a way to do it (though it may be easier with a mouse than a trackpad). For the FPS portion, I recommend trying to keep your back against the wall, and moving along the walls as you shoot the pathogens. You can get them to kinda bunch up together and take them out more quickly. If your back is always exposed, it's easier for the faster pathogens to kill you.
I hope this helps!