Remember that the invae in general have grown more canny in interacting with humanity. Subtlety is the name of the game now. As always, consider the nature of the insect itself.
A smart Locust queen might actually send her workers ranging much farther afield (50-100 miles) to locate and pluck new, useful targets. Lower-caste people to become true forms; more 'installed' individual to try to make good-merge flesh-forms, and be able to move the swarm from location to location. Never sticking with more than two or three people together at once as they move; they 'land' in a new field, stay there long enough to brood a couple/three more spirits, then move onto the next location. A really good Queen like this might manage to have two or three lesser queens under her control, building a serious swarm ...