Gene therapy is being investigated as an alternative treatment for a w
ide range of infectious diseases that are not amenable to standard cli
nical management. Approaches to gene therapy for infectious diseases c
an be divided into thr ee broad categories: (i) gene therapies based o
n nucleic acid moieties, including antisense DNA or RNA, RNA decoys, a
nd catalytic RNA moieties (ribozymes); (ii) protein approaches such as
transdominant negative proteins and single-chain antibodies; and (iii
) immunotherapeutic approaches involving generic vaccines or. pathogen
-specific lymphocytes. It is further possible that combinations of the
afore mentioned approaches will be used simultaneously to inhibit mul
tiple stages of the life cycle of the infectious agent.