Mites thrive in bp conditions. They could hitchhiked from a pet store and it took until now to spot them. I don't think you have to worry about them infecting everything in your house but you will need to do proper cleaning in order for them to not come back.
I used Provent A Mite (PAM) and Natural chemistry Reptile Spray when I had mites. PAM is used for in enclosure, you remove animal and water sources then spray enclosure and wait at least a half hour to air out before placing animal and water dish back in, substrate and everything can stay in cage but water bowl and snake need to be removed. Make sure to read directions and follow exactly as this stuff can be deadly if used improperly! Reptile spary is used on your snake (can be used for enclosure also but IMO PAM works better), while the PAM airs out of the enclosure spray some reptile spray on paper towel and let the snake run through it a few times and it will give relief to your snakes and kill the mites on them. Read directions and use properly. Then your going to want to clean the outside of cages, stands, carpet, everything in that room. I repeat PAM and Reptile Spray once every 7 days for a month and then every 14 days for another month and clean room completely every 2 weeks for 2 months, I have not had mites since.
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