Abstract: Peptides of the general formula (I): I-A-B-C-D-E-F-G-H-II are disclosed as being active against Herpes virus infections in animals and human beings, wherein A is Ala, Gly, Val or absent; B is Ala, Gly, Val, Ser or absent; C is Ser, Thr or absent; D is Ser, Thr, Ans, Glu, Arg, Ile, Leu or absent; E is Ser, Thr, Asp or absent; F is Thr, Ser, Asn, Gln, Lys, Trp or absent; G is Tyr or absent; H is Thr, Gly, Met, Met(O), Cys, Thr or Gly; I is Cys or absent, and II is Cys, an amide group, substituted amide group, an ester group or absent, wherein the peptides comprise at least 4 amino acids and physiologically acceptable salts thereof.