Pets have died, fleas have not
We have a very messy house, lots of accumulated clothing and some upholstered furniture, severe flea infestation left behind from one cat in one room, moderate to few in other rooms / areas. Wife in hospital for at least another week, no pets or people in house. Flea bombed extensively Sunday, I've been out of house 4 straight days; stopped in house last night; some are still there, about 5 or 6 in total during my 10 minutes in the house jumped on my slacks, I picked off or sprayed. Was a dozen or 2 last week when I went in the one worst room. Am I gaining ground? Will they die off without animal hosts? Should I bomb againA before serious vacuum cleaning? Does baking soda really work?
Do not use a flea bomb again. It will spread pesticide over everything in the house, not just the target areas where the fleas are. You, and especially your wife, should not be contacting pesticides.
Remove everything you can on the floor so that it is as clear as possible. Vacuum floors and upholstered furniture. Reach into cracks and crevices. Then spray as described in our flea webpage: https://extension.umd.edu/hgic/fleas
When you pick off a flea, kill it by crushing between your fingernails. Wash your hands. Wash old pet bedding. Wash any clothes that were on the floor.
As you'll read, flea sprays will kill most flea life stages, but some life stages can survive for a year. If you follow the above recommendations, most fleas will be gone in a few weeks. Be vigilant. Respray when necessary.
Fleas like moist environments, so when the weather gets cold, if you have forced hot air heat, that will help discourage the fleas.
When you are vacuuming up live fleas, be careful about how you dispose of the vacuum contents or bag. Don't leave them around where the fleas can hop out!