How do you counter abilities that track and do damage?

i am talking about those stupid spider robots that run at you and take a big chunk of your hp everytime they hit you and about those other stupid bugs that run at you and on top of dealing dmg they drop a puddle of mud or oil on your feet, how do you even coutner that in cqc?? Like, the moment I see them I barely have time to shoot them and most of the times it means certain death cuz I am already low on hp