The largest study of the current outbreak found that in nearly 13% of "confirmed and probable" cases in Liberia, Sierra Leone, Guinea and elsewhere, those infected did not have fevers. The study, sponsored by the World Health Organization and published online late last month by the New England Journal of Medicine, analyzed data on 3,343 confirmed and 667 probable cases of Ebola.  87.1% of those infected exhibited fever — but 12.9% did not.  more at url