The Semliki Forest virus is an alphavirus found in central, eastern, and southern Africa.

The outermost surface of the virus is almost entirely covered by heterodimers of glycoproteins E1 and E2, arranged in interconnective trimers, which form an outer shell.

Replication occurs via a negative strand intermediate giving rise to a full-length genomic RNA for export in new virions and a subgenomic message that is translated into the structural proteins.

In this one case, the patient was speculated to be immunodeficient and potentially had been exposed to large amounts of virus in the laboratory.

[9] The modified virus was also found to efficiently kill human glioblastoma tumour cell lines.