Finding "Flea Dirt"...Confused

Hello all!! When I adopted my kitty, she showed no signs of fleas but I started her on Frontline and noticed that some dead fleas fell off her a day or two later. No big deal, I thought hey at least it wasnt an infestation, and whatever was there is gone now.

Fast forward 3 weeks...and I'm finding flea dirt on her. Out of the clear blue. She is strictly an indoor cat and has shown no signs in the past few weeks. I got home from work tonight and was holding her, looked down and it was all over me!

Luckily I have a very tolerant kitty, so shes let me pick over every inch of her fur searching. She has a short white coat, and the flea dirt seems to only be on the outer coat, no sign of any dirt (or fleas for that matter) on her skin.

So - 2 questions....

1. Is there any chance that this is residual dirt from the few fleas that were on her 3 weeks ago? I just think its strange I've seen nothing until today.

2. Should I go on and give her another dose of Frontline on her? I don't think she's technically due for it for another week or so. Couldnt hurt right?? It just makes me itch thinking about it!! 

Thank you!

Are you sure she didn't roll on dirt someplace? Possibly a potted plant? Since you say the dirt is only on her outer coat and not next to the skin, I'm wondering if she got into something.

If it's flea dirt it will turn red when wet. Put some of the dirt on a white paper towel and sprinkle some water on it. Does it turn red, like blood? And it will be deep in the fur, and on the skin, not on the surface of the coat. I agree with the above poster, sounds like she's been rolling in something.

I did the water test last night...definitely turned red. I went on and put some flea dropper on her. Huge mistake. I used Seargent Silvers that I had purchased as backup since I normally receive samples of Frontline from the vet. I had no idea the information that was out there on that poison. I felt horrible, and immediately gave her a bath to try to get every bit of it off of her. She hasnt experienced any adverse effects from it...after reading the horror stories online, I'm more than thankful. It was a long, sleepless night though.

If by chance anyone reading this has not heard about the ill effects of using Sergeant Silver (or Hartz Brand) please take a moment to google it. Hundreds, if not thousands of animals have died leaving pet owners with horrible guilt. The fact this stuff remains on the market is disgusting!!!
 

Don't beat yourself up about it.  I hope that she continues to feel okay.