Uganda-born Johnson Aziga, 52, a former research analyst with Ontario's Ministry of the Attorney General, is also accused of 13 counts of aggravated sexual assault. Those charges include the cases of 11 other women he is alleged to have had sex with and to whom he did not disclose he was HIV positive. He has pleaded not guilty on all counts.
The trial by jury is expected to last about six weeks.
The Supreme Court of Canada has previously ruled that one partner cannot give true consent for sexual relations if the other partner fails to disclose an HIV infection.
As a result, Aziga's trial could find that the two women's deaths resulted from sexual assaults, calling for a first-degree murder conviction, which carries an automatic life sentence.
The aggravated sexual assault charges carry a maximum sentence of 14 years in prison.
Aziga's lawyer, Davies Bagambiire, called it a landmark case.
"This is the first time that a Canadian is prosecuted for alleged murder through the alleged dissemination or transmission of the HIV virus," Bagambiire said. "I look forward to the evidence unfolding so I can shake it up, cross-examine and demonstrate the holes in the evidence that I believe exist."
Aziga has been held in custody for the five years since his August 2003 arrest. His trial has been delayed many times due to adjournments sought by the defence. Aziga has fired three legal teams leading up to the trial.
The criminal charges will do little to protect the public, said Alison Symington, spokeswoman with the Canadian HIV/AIDS Legal Network. The best way to protect the public is to promote education about the illness and to encourage disclosure and the use of condoms to prevent transmission, she said.
"These are very rare cases indeed, but there's so much attention to them and so much misinformation and panic around them that it really kind of increases stigma and discrimination, which ultimately may be counterproductive," Symington said.
The Canadian HIV/AIDS Legal Network estimates about 60,000 people are living with HIV in Canada.
There has been a notable increase in criminal charges for HIV transmission since 2000, Symington said.
Clato Mabior, an HIV-positive man in Winnipeg, was sentenced earlier this month to 14 years in prison on six counts of aggravated sexual assault, as well as one count each of invitation to sexual touching and sexual interference.
Carl Leone was handed an 18-year sentence on April 4 after pleading guilty in Windsor, Ont., to 15 counts of aggravated sexual assault after failing to inform his sexual partners of his HIV status. Five of the 15 women are now HIV positive.
Former Saskatchewan Roughrider Trevis Smith, who is HIV positive, was sentenced Feb. 26, 2007, to 5― years in prison for aggravated sexual assault. He was found guilty for knowingly exposing two women to the virus that causes AIDS.
Adrian Betts, acting executive director of the Hamilton AIDS Network, said many HIV/AIDS groups will be watching Aziga's trial closely.
Betts said in many HIV/AIDS cases the evidence comes down to a discussion of "he said, she said" regarding if disclosure occurred.
Betts said he believes the onus should really be on individuals to protect themselves.