This past weekend, Lana Del Rey held a surprise book signing for her new poetry book Violet Bent Backwards Over The Grass at a Los Angeles Barnes & Noble. Photos from the signing went viral, mostly because Del Rey wore a sheer mesh see-through face mask that didn’t seem to cover her face at all. Now Billboard has spoken with an infectious disease specialist who confirms what most people already guessed: That mask isn’t doing anything to prevent any diseases getting in or out.

Speaking to Billboard’s Rania Aniftos, Dr. Peter Chin-Hong said, “I am not very confident that [Del Rey’s face mask] would prevent any spread of COVID… It looks interesting, but you don’t need to be a smart virus to get through that mesh. You could be the dumbest virus, and it would be easy to get through that mesh.”

Chin-Hong is a medical educator at the University Of California, San Francisco, and he names Lady Gaga as someone who is “still able to be fashionable and have an effective mask.” Del Rey’s mask, on the other hand, isn’t even remotely effective: “The holes are so big in the mesh that you might as well be wearing nothing. I can draw a mask on my face with a magic marker, and it would have the same efficiency as a mesh mask.”

Some people have wondered whether Del Rey could’ve had some kind of clear, invisible layer under the mesh. Chin-Hong says that one option, the ClearMask, does make the user’s lips visible, something necessary for people who read lips. But Del Rey wasn’t wearing one of those: “The clear part [of the ClearMask] is just around the mouth, because plastic blocks the virus, so you can still breathe through fabric from the nose.”

Chin-Hong also points out that “mask shaming” is not the way to get Del Rey, or anyone else, to change habits: “If somebody said, ‘Hey, Lana, I wonder why you wore that mesh mask’ — and said it in a nice, kind, curious way — she might say, ‘Oh, I didn’t really know. You’re right, maybe this isn’t the best mask.’ Then Lana Del Rey could be the next Lady Gaga and go out there and promote masks.”

A couple of days after the signing, Del Rey posted a video of herself reading a poem while wearing a more conventional and effective cloth mask.

Maybe she’s learning!