The best control is to keep your premises clean and vacuumed to get rid of eggs and larvae. Launder pet bedding frequently. In heavily infested areas treatment with flea control products may be necessary. The orange trees have yellowing leaves that are dropping. There are small insects present.
Various insects can cause yellowing foliage.
They could be sucking insects called scale, which can cover the branches in severe infestations. They can be difficult to control once they reach adult size. Natural predators can control scale. Supreme oil can be effective if applied at the right time. My redwoods look stressed and the ends of the branches are dying.