Alphavirus

Alphaviruses are a genus of enveloped, positive-sense single-stranded RNA viruses within the Togaviridae family, primarily transmitted by mosquito vectors (Wikipedia, 2024; NCBI Taxonomy). They are globally distributed and categorized into Old World alphaviruses, such as Chikungunya virus (CHIKV), which cause debilitating polyarthritis and fever, and New World alphaviruses, such as Eastern Equine Encephalitis virus (EEEV), which can lead to severe, often fatal, encephalitis (Nature Reviews Microbiology, 2017; CDC, 2023). The viral genome encodes non-structural proteins (nsP1–nsP4) essential for RNA replication and structural proteins (C, E3, E2, 6K, E1) required for virion assembly and host cell entry (UniProt, 2024). Therapeutic development focuses on inhibiting key viral enzymes like the nsP2 protease or the nsP4 RNA-dependent RNA polymerase, as well as blocking viral entry mediated by the E1/E2 glycoproteins (Journal of Virology, 2020; PubMed, 2021). While several broad-spectrum antivirals like ribavirin and favipiravir show in vitro activity, the lack of highly specific, approved treatments remains a significant challenge in managing outbreaks and chronic sequelae (NIH, 2023; PubMed, 2022). Additionally, the high mutation rate of RNA viruses poses a constant threat of drug resistance, necessitating the development of combination therapies or highly conserved targets (Nature Communications, 2021).

Other names

TogavirusAlphavirus genusGroup IV virus

Inhibition of RNA-dependent RNA polymerase (nsP4), inhibition of viral protease (nsP2), inhibition of viral methyltransferase (nsP1), and inhibition of viral entry/fusion mediated by E1/E2 glycoproteins.