Seems the most natural translation to me - other phrases used are "a 2-day course of [symptoms]", "a clinical picture characterized by ...", but the "más o menos" makes putting it all together sound unnatural to me :).

Spanish term (edited): con un cuadro de mas o menos 2 dias de evolucion

"Clinical picture" is correct, but I think an argument can be made for plain language.

"Most physicians, if asked to distinguish between signs and symptoms, would reply in a fashion something like this:

A symptom is a manifestation of disease apparent to the patient himself, while a sign is a manifestation of disease that the physician perceives. The sign is objective evidence of disease; a symptom, subjective. Symptoms represent the complaints of the patient, and if severe, they drive him to the doctor's office. If not severe, they may come to light only after suitable questions. The patient perceives, for example, subjective pains and discomforts [Doctor, I have a bad headache], or disturbances of function [Doctor, I can't move my arm the way I used to], or some simple appearance [Doctor, I have had this rash for the past ten days and I'm worried about it]."