Any food still left after leftovers have been reheated once, should be thrown out. Dishwashing brushes can also be put into the dishwasher. If washing dishes by hand, leave them to drain rather than using a tea towel. If you must use a tea towel, change it often. Dishcloths are a prime spot for bacteria to multiply.
Paper towels are a better option.
If you do use dishcloths, have several available and put them regularly through the washing machine, using the hot cycle. Antibacterial products may help fight bacteria, but should be used in addition to regular cleaning, not instead of it.