Analysis fails to back HIV sex charges, court told

An international expert on HIV transmission has told a trial scientific analysis does not prove a man infected his sexual partners with HIV.

Stuart McDonald is accused of deliberately infecting his sexual partners with HIV in Adelaide in 2005.

The South Australian Supreme Court trial has previously heard he lied to the men or tricked them into having unprotected sex.

He had been accused of infecting eight men, but the judge directed the jury to find him not guilty on one count because the evidence showed the alleged victim had HIV before the time he said he had sex with McDonald.

The defence told the jury it would call one witness, Professor Anne Vandamme.

She said phylogenetic analysis of the virus could not be used to prove transmission, only to exclude it.

Professor Vandamme said it was unlikely McDonald infected five of the alleged victims, but she needed more analysis to reach conclusions about the others.