[jlgaddis]

> ... but they would only accept mail or fax.

It's because the USPS (and FedEx, UPS, et al.) and fax are considered "secure" methods of transmission for confidential or private information (including PHI).

E-mail is not, because it travels over the public Internet.

[Rjevski]

But technically it’s just as insecure, if not more - email has opportunistic encryption, fax doesn’t.