It is well known that bed bugs excrete a black liquid after a blood meal. The evidence is often noted in black spots on mattress edges or other areas close to where bed bugs harbour. When bed bugs are well fed they become elongated and quite fat with the blood volume. In starvation settings the bugs lose the elongated shape and gain a more stereotypical appearance. If starved long enough they become paper thin and eventually die. We have noted that some adult bed bugs can appear almost translucent because of starvation and fluid loss.
I have been experimenting with bed bugs for several years and have noted that bed bugs continue excreting the black dots weeks after feeding. As such each blood meal might have several excretions. Given that bed bugs contain very little mass and are subject to dehydration and death I wonder if we could not attack that vulnerability. If a bed bug could be given diarrhoea they would continually lose their moisture and die due to dehydration.