Daily Press, Aug 5, 2014 (emphasis added): MYSTERY ILLNESS — Alyssa Langel['s] three-year-old horse [...] has large patches of skin exposed. [Owners] remain unsure what caused many horses to manifest swollen eyes and lips, as well as blisters [...] They heard of a similar outbreak affecting other horse communities in California.
CBS, Aug 6, 2014 (h/t Anonymous tip): There’s a mystery about what’s making dozens of horses sick here in Southern California. >> Watch it here
Kendall Melline, owner of sick horses: “It’s devastating… I’ve got my national champion, who her entire body, her entire first layer of skin is going to fall off.” [...] She’s not seen any improvement in Bunny and is very concerned.
Melline: “Her eyes are swollen almost completely shut… I’ve heard about 70 other horses have come down with something like this.”