We rent rooms in a private residence which is infested with bed bugs that the owner/landlord refuses to do anything about it. Who can help us?

Perhaps your attitude is one more reason the landlord won't do anything that encourages you to stay. Good luck, and when you have to move out be sure to clean up or get rid of anything that might be infested.

vegaslady: don't you think we would do that uf we could? Keep your rude, no-help comments to yourself and people like you shouldn't be allowed to post DUMB answers like YOU did!!

You didn't state where this is. The landlord/tenant laws are different for each state.

Begin by looking up and reading the state law...
Go to this website and scroll down the list till you find your state.

Carefully read. You should be able to figure out what your options are...

https://www.thelpa.com/lpa/lllaw.html

Move out