You can have them in multiple rooms instead of a single one, but I'd forego this to avoid your entire house sounding like an annoying insect instead of just one room. You also need to keep them in your house so they can influence the HHA score... at LEAST until they stop having an effect in September. They get phased out as lucky HHA point influencers as of August 31st. Your score will literally drop close to 50,000 points overnight.
Your house gets assessed daily at 6am based on what's inside. If the bugs aren't there, you don't get your extra points.
Thanks for your answer. I think I'll just stay away from having them in my house. Knowing me, they will be gone before the day would be over lol.