Anti-NMDA Receptor Encephalitis striking southeastern PA

This is weird:
CBS Philly: It’s a mysterious, newly discovered disease that strikes mainly young women, and it’s often misdiagnosed. Doctors who discovered it, here in Philadelphia, say it’s like your brain is on fire

More:

Young women dazed, restrained in hospital beds, acting possessed and then becoming catatonic. They’d been so normal, when suddenly their lives went haywire.

“One minute I’d be sobbing, crying hysterically, and the next minute I’d be laughing, said Susannah Cahalan, of New Jersey.

The other scary thing is that very often it may be completely misdiagnosed as a mental disorder .., or even in the religious world, as a satanic possession..





So…why the cluster?