Yellow fever virus 17D strain (YFV-17D)

The Yellow fever virus (YFV) 17D strain is a live-attenuated variant of the wild-type Asibi strain, belonging to the Flaviviridae family. It is an enveloped virus containing a positive-sense single-stranded RNA genome that encodes a single polyprotein, which is subsequently cleaved into three structural proteins (C, prM, E) and seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, NS5). The 17D strain is the basis for the highly effective yellow fever vaccines, such as YF-VAX and Stamaril, which induce long-term immunity through the production of neutralizing antibodies and robust T-cell activation. In a therapeutic context, the virion and its components serve as targets for the development of antiviral agents and monoclonal antibodies aimed at treating severe infections or managing rare vaccine-associated adverse events. While generally safe, the 17D strain can occasionally cause serious viscerotropic or neurotropic complications, particularly in individuals with underlying thymus disorders or those who are immunocompromised.

Other names

Yellow fever virus vaccine strain 17DYF-17D17D-20417DDYellow fever virus (strain 17D-204)

The 17D strain acts primarily as a live-attenuated vaccine that triggers a potent, polygenic immune response involving neutralizing antibodies and cytotoxic T cells. Experimental antiviral drugs target the virion by inhibiting the viral RNA-dependent RNA polymerase (NS5) or preventing viral entry by targeting the envelope (E) protein.