Acuna-Soto also had access to exhaustive diaries kept by Francisco Hernandez, the surgeon general of New Spain who witnessed the second catastrophic epidemic in 1576.
He described a highly contagious and lethal scourge that killed within a few days, causing raging fevers, jaundice, tremors, dysentery, abdominal and chest pains, enormous thirst, delirium and seizures.
Most recently, scientists have turned their work towards the possibility of disease. The climate was humid and would have supported a host of parasitic activity. As the Mayan civilization grew and spread, disturbances would have occurred which could have placed the people in contact with parasites that would promote disease and death.
If this were the case no member of the Mayans would have been spared. As with many diseases that attacked the human body, death can be a slow process dependent upon the strength and health of the individual attacked.