I would first like to say thank you for the information (and sanity) you provide.
I first noticed fleas on my indoor cat 12 weeks ago, at which point our house was already infested. I vacuum constantly but have old pine floorboards with 1/4 inch gaps between them (the perfect place for fleas to nestle in). I immediately applied Advantage and have done so every 3 weeks. After 4 weeks, I noticed a drop in adult fleas in the house and by 8 weeks thought we were out of the woods; however, this week (week 12) I have noticed a surge of adult fleas (I picked 5 off my ankles within 1 hour). Like I said, I have been continukng to treat the cat with advantage and allowing her free access to the house. when she gets up from her bed I see dead fleas, so I hope that means the advantage is doing its job.
Is this still within a “normal” time frame to see adult fleas emerge that were laid BEFORE I did the first Advantage treatment? First treatment was October 26. Apartment is kept between 58 and 68 degrees which I know can have an impact of how long it takes fleas hatch, pupate, etc… Is it normal for the adult fleas to emerge is a “wave” like this?
I thought we were in the am now I’m beginning to wonder if somehow they’re laying eggs, or if this is hopefully the final emergence. I don’t want to get rid of my cat but this has caused so much stress in the house…I’m at my wits end!
Most infestations end in around 8 weeks after treatment begins. However, sometimes they can last longer, especially in severe infestations. If your cat has been consistently treated with Advantage, then the fleas shouldn’t be able to lay eggs. So, the current generation of fleas you are seeing should be last.
What can make infestations last longer is the cocooned adult stage. After becoming adults, fleas can stay inside their cocoon and enter into a quiescent (dormant-like) state for up to 5 months. However, they will rapidly wake up and emerge when they detect a host resting on the cocoons (heat and pressure). Vacuuming can help simulate these host cues and force emergence.
Have you been vacuuming regularly, especially using the nozzle attachment for the gaps in the hardwood? Another option would be to steam clean those gaps.
It takes new eggs 17-26 days to become adults in homes. And, as mentioned, the pre-emerge adult state can last 5 months. So, it’s possible to continue seeing fleas for up to 6 months after treatment begins. However, the population should be diminishing. Perhaps the surge you saw was cocooned adults waking up. But if you notice consistently more fleas, or the infestation continues for longer than 6 months, something fishy is going on. It may be a good idea to hire professional pest control at that point.
I hope this helps.