Disclosed is the use of poly(I:C12U) in the manufacture of a medicament for the treatment of a subject infected with a virus, wherein: said medicament comprises poly(I:C12U) in an amount sufficient to bind to Toll-Like Receptor 3 (TLR3) without activating other Toll-like receptors or RNA helicases, to reduce or eliminate infection of the subject by the virus, and said amount of poly(I:C12U) in the medicament is between 2.85mg/kg and 5.71mg/kg body weight of the subject. Further disclosed is the use of poly(I:C12U) in the manufacture of a medicament for the vaccination of a subject against a virus, wherein: said medicament is formulated for administration with a vaccine which induces an immune response against the virus, said medicament comprises poly(I:C12U) in an amount sufficient to bind to Toll-Like Receptor 3 (TLR3) without activating other Toll-like receptors or RNA helicases and to stimulate the immune response against a viral antigen of the vaccine in a subject, and said amount of poly(I:C12U) in the medicament is between 2.85mg/kg and 5.71mg/kg body weight of the subject.
