What kind of mites could these be?

[Ratmosphere]

So my sister watched over her friends hamster while she was away. After a while of keeping the hamster, my sister and her roommates started to get bit by mites. What kind of mite could hop on a hamster and reproduce like that?

 

[sdsnybny]

Sounds more like fleas than mites

 

[Ratmosphere]

You think?