It would depend on how infectious the bodies would be after death, I think. That would be a lot easier to clean up than living beings. I'd imagine it would also be far, far easier in smaller towns than London - but I can see British pride demanding London be reclaimed first.Manchester is also an example of slow recovery would be; even if the Ragers die out within 28 weeks, then it is going to take ages for a proper clear up. Even starting from military bases every cellar, cupboard, attic, sewer, car, truck, shop, floor of a skyscraper needs to be checked for surviving Ragers, or disease carrying survivors. It would never be quick, never be clean, and never be nice. Ten years might even be too short a timescale.
Also, I always had trouble with them dying of hunger - they would have died of thirst long before that. Still a great film, though.