If I remember correctly from historic accounts the symptoms also include “coffee ground” vomit. I think it is the Jacksonville cemetery that has a section of yellow fever graves.
A lot of older cemeteries here in Florida have yellow fever sections. People died very quickly, nobody knew how it was spread, and it really set off panics when it appeared (which it did fairly often). Jacksonville had a particularly bad outbreak in the 1880s.
Vomito negro...black vomit.