I'm sure I'll get flamed for this, but when using tongs to first put the chicken on the grill, I will stick them into the flames for a few seconds before laying them on the side board. Then after each turn of the chicken I'll stick them through the grates for a few more seconds to "hopefully" kill off any lingering bacteria. Can't say I have ever wiped down the tongs between use and have been doing this for now on 30 years and haven't gotten sick from it.