There is a non-chemical way to control them:

The lead researcher also examined vacuum bags for toxicity and exposed fleas to churning air in separate tests to further explore potential causes of flea death. He and a colleague believed that the damaging effects of the brushes, fans and powerful air currents in vacuum cleaners combine to kill the fleas. The study used a single model of an upright vacuum, but researchers don't think the vacuum design has much bearing on the results.

What I don't get, though, is how you get the cat to lie still while you run the Hoover over her. I know that Jessica wouldn't stand for it for a microsecond. And it would be tough to do a good job on the tail. Maybe they'll do some further research.