i always use a 1/10 bleach water combination when cleaning. stronger for things i collect out doors. if outdoors i wash in soap and water first then bleach. this should kill off all the stuff you don't want. after that rinse really well. after i wash it in the bleach i let it soak for several hours and rise again. want to make sure you get all the bleach out.
alcohol could be used too, but bleach gives the best results. this kills everything. however one drawback is that it can change the color of wood. i have found it has lightened up many logs i have.
I am sure some people may not like the idea of bleach, but as long as it is rinsed well it should not be a problem.