This is a hyphenated name of a disease, and should not use an endash or emdash. --EncycloPetey (talk) 23:20, 22 January 2019 (UTC)

It's a disease named after two people, and so their names are joined by an en-dash. See MOS:DASH for detailed explanation. Cherkash (talk) 23:36, 22 January 2019 (UTC)
The WP:MOS applies only at the English Wikipedia, not anywhere else. Wikisource reproduces documents as they were printed, and the scan clearly has a hyphen, not an endash or emdash. --EncycloPetey (talk) 00:55, 23 January 2019 (UTC)