IMHO, all live foods for our fishes caught in the wild harbour diseases. No matter how clean the habitat where they come from, the risk of unknown diseases are there. So feed them to your fishes cautiously.
As a treat, my guppies and angels they will have live tubis once or twice a week. Of course, after rinsing them several times in a plastic container and ensure no other foreign particles are seen, only then I feed to my fishes. To prolong the life span, the tubis are kept in plastic container with some amount of tank's water that will be left floating on top of the fish tank. The tubis will be kept no more than 2 days.
Unless you hatched or raised the live foods by yourself, then only you can be sure of their cleanliness. I hatched BBS myself and fed my guppies and angels almost daily, touch wood, without any problem.