Abstract: A paratransgenesis system is disclosed to kill targeted social insects such as termites and cockroaches, for example the Formosan subterranean termite. A genetically modified yeast can be effectively used to express and deliver lytic peptides directly within the termite gut. Some highly lytic peptides directly damage the insect gut itself, leading to the death of the insect within about three days. Other lytic peptides kill all (or at least most) species of protozoa in the termite gut. The protozoa provide wood-digesting enzymes (cellulases) to the termite. Without these protozoa (and their cellulases) the insect dies within about six weeks. The system is completely free from conventional neurotoxins and other organic pesticides.