Abstract: The present disclosure relates to the determination of the complete genomic nucleic acid sequence of a new simian immunodeficiency virus (SIVcpzTAN1) isolated from a wild chimpanzee (Ch-06) from the Gombe National Park in Tanzania and to the nucleic acids derived therefrom. The disclosure also relates to the peptides encoded by and/or derived from the SIVcpzTAN1 nucleic acid sequence, to host cells containing the nucleic acids sequences and/or peptides, to diagnostic kits, immunogens and methods which employ the nucleic acids, peptides and/or host cells of the present disclosure, and to non-invasive methods for the detection of SIVcpz and related viruses from animal species in the wild.