The bottom line is that you need a new carpet (or other flooring).

What is happening is that your vaccuum cleaner is loosening up all the bacteria that has settled onto/into your carpet, and that bacteria is staying in the air for hours before settling back down onto your carpet again.

The dirt in carpets will accumulate over time and will include dead skin cells, hair, cellulose fibers from toilet paper and newsprint, all of which are organic and all of which will provide food for bacteria.

Please don't shampoo your carpet. If you do, then getting it wet will create a bacteria's idea of heaven; plenty of food for the bacteria to eat, and plenty of moisture for the bacteria to move around in the carpet. The result will be that your carpet will stink just like the fragrance "Wet Dog".

If I wuz you, I would vaccum the carpet multiple times with a bagged vaccuum cleaner to remove the bacteria from the carpet. And, I would also start budgeting to buy a new carpet.

While every carpet vaccuum cleaner and shampoo'er manufacturer will brag about how clean his machine will get your carpet, the truth is that, with time, organic materials will penetrate deep into your carpet so deeply that they won't be removed by vaccuuming or shampoo-ing. When carpet cleaning contractors are asked to clean carpets like that, they add a biocide to their solution tank. This biocide kills all the bacteria it comes into contact with, thereby preventing those bacteria from multiplying and creating that "wet dog" smell in the room. That's not the correct fix. The correct fix is to replace the carpet, but carpet cleaning contractors would much prefer to do the work, get paid and get out than argue with the customer over the age and condition of their carpet. So, they add the biocide to ensure they don't get "My carpet stinks now!" phone calls from their customers; do the cleaning and get out. It's me that's telling you the truth cuz you're not paying me nothing.

What you need is to try cleaning your carpet with a bagged vaccuum cleaner that's fitted with the MANUFACTURER'S filter bag. No Chinese knock-off filter bags. Get a Hoover filter bag if you're going to use a Hoover. Vaccuum your carpet every weekend for a month, and throw the filter bag in the garbage.

Then see if your carpet stinks after vaccuuming it with your bagless vaccuum cleaner.

- Nestor