if you are worried about any of the strips running you can test those strips- but not wash them all- if you do have a bleeder you can rinse it until it stops- then hang to dry- or wrap in a towel to absorb as much water as possible- then press -
if you decide you need to pre-wash them using a mesh laundry bag helps keep the tangling and fraying to a minimum.
it is a personal choice- but normally the manufacturers do not intend their pre-cuts to be pre-washed.