Put tile floors on the buses with a center drain down to the street. Then hose down the riders to wash the bedbugs away
Yeah, I can see it all now:
Overhead plumbing with an onboard water supply. A constant flow of water for the first couple of minutes. A smattering of writhing bedbugs on the street, in the bus's wake.
Obviously some stops would have a higher delousing yield than others.
Remember, public transportation. It's their duty to preserve your health and safety.