The toilet, like the bathroom, is a humid area of the house due to the amount of water in the cistern, and as we know - germs love a humid environment to breed in.
Bacteria in the toilet absorb organic waste and release gases which smell - bad. Hence the importance of hygiene.
Bacteria can mostly be found in the toilet bowl but they're also lurking on the seat, the floor, the flush and the door handle. Bacteria can also be found in limescale deposits.
Every time you flush the toilet, they are projected into the air, up to 1.5m high, and then cover all the surrounding surfaces. If your toilet is in the bathroom, bacteria can even land on your toothbrush!
Shut that lid before you flush!
It is important to remember to clean the toilet brush which spreads bacteria in the same way as sponges, cloths, face cloths, etc.