Even more basic and critical - do NOT use a grocery cart flip down/out section to put food items in. I never use the big carts. Always the ones without child seats.
I always grab my carts from the cart corral outside. I take the ones that have been sitting in the sun the longest.
UV disinfects wonderfully.
i use the ones with the flip down section but i wipe it on both sides, and i wipe the bar you push the cart with.
Otherwise who knows between baby diapers and small doggies asses.