Inactivated West Nile Virus Lineage 2 (NY 2001-6263)

West Nile virus (WNV), a member of the Flaviviridae family, is a mosquito-borne pathogen primarily transmitted between avian hosts and mosquito vectors, occasionally to humans and other mammals. The genetic diversity of WNV has led to its classification into multiple lineages, of which lineages 1 and 2 are of greatest clinical significance. Lineage 1 has historically been associated with large outbreaks in Europe, the Americas, and Africa, while lineage 2 has emerged as a significant pathogenic strain, particularly in sub-Saharan Africa and, more recently, in Europe.

Genetically, lineage 2 differs from lineage 1 in structural and nonstructural proteins, potentially impacting transmission efficiency and disease severity. While both lineages can cause neuroinvasive disease (e.g., encephalitis, meningitis), lineage 2 has demonstrated rapid spread and increased virulence in some outbreaks. Notably, mutations in the NS3 and E proteins have been associated with enhanced West Nile virus replication in mammalian hosts.