The cocoliztli epidemic of 1576 and the record kept of it

The epidemic that halved what was left of the indigenous population of central Mexico in two years, and the paper trail it left. The crown's protomédico wrote down the clinical picture; bodies were opened and the organ findings written up; tribute counts were taken in 1570 and 1580 on either side of it. Modern epidemiology still works from those documents and still cannot say what the disease was. The record is the contribution; the thing recorded is the catastrophe.