Colloidal silver, at least according to this powerpoint.  I can’t find the actual research paper and the publishing journal isn’t listed.  Is it being suppressed?

http://www.thesilveredge.com/pdf/defense-threat-reduction-agency-silver-nanoparticles-neutralize-hemorrhagic-fever-viruses.pdf

Reprise: Ebola: Feds Blocked Shipments of Colloidal Silver to Africa

Ebola: The Source and the Solution