It can be hard to relax on vacation when you imagine that your hotel room is a petri dish of previous guests’ germy discards, even if there aren’t the usual telltale signs of uncleanliness.

Here, germ experts give us all the grody details — and the best ways to protect yourself while hitting the road this summer.

Shower surfaces

The hotel tub is teeming with existing bacteria, so it’s best to skip the bath and limit exposure by showering. “Keep in mind there’s a [film] that forms over time in the tub and that holds organisms,” says Philip Tierno, a microbiologist and clinical professor of microbiology and pathology at NYU School of Medicine.

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