Do roaches bite yahoo. Why are most people more scared of roaches than ants? I had 3 marks, and 5 the next day NO I did not sleep in there the following days.!! The Boric acid killls them, the sugar attracts them to it, and the flour makes it thick. I had seen 2 really small one crawling and I called my dr,did some internet reading, and called the pest control people and all confirmed that they DO bite. Would it be ok if a swapped them sometimes? Roaches and spiders? Existing questions. Could it have been that? Hope this helps. We have since then been killing them and taking down their population!