In a consensus statement presented Friday at the Canadian Conference on HIV/AIDS Research in St. John's, the six HIV experts said the latest scientific evidence shows the risk of sexually transmitting the virus varies from low to zero in many cases.
"We thought it was really important to provide the criminal justice system with a very concise statement about what we view as the risk of transmission and how HIV has really become a chronic, manageable disease," co-author Dr. Mark Tyndall said in an interview.
There have been more than 150 cases in Canada in which people with HIV have been charged, mostly with aggravated sexual assault, for not disclosing their infection — sometimes years after the initial sexual encounter occurred.
"The vast majority of the convictions ... have not resulted in any HIV transmission," said Tyndall, head of infectious diseases at Ottawa Hospital, pointing out that in Canada, even a possibility of transmission can lead to prosecution.
In 1998, the Supreme Court of Canada ruled that people with HIV must inform their sex partners of their condition or face a charge of aggravated sexual assault, which carries a 14-year prison sentence on conviction and can lead to a potentially lifelong designation as a sex offender.
That decision was updated in October 2012, when the high court considered two separate cases from Manitoba and Quebec, both dealing with heterosexual interactions.
The justices ruled 9-0 that anyone infected with HIV is not legally obligated to inform sex partners about their condition — as long as they have a low level of the virus in their body due to treatment and they also use a condom.
"Many of the cases are really domestic disputes. Some of the more egregious cases are people (charged) 10 years after the fact. And even in long-term relationships, where they've known that their partner is positive, they go back and charge them for the very first time they had sex," Tyndall said.
While he doesn't have exact figures, Tyndall estimated that about 75 per cent of the cases involve heterosexual interactions, although the law also applies to men who have sex with men.
The doctors say that having sex using a condom or with effective antiretroviral therapy poses a negligible possibility of passing on the virus.
"With heterosexual transmission, it's about one in a thousand per contact. So I think people have a false impression that if you have sex with somebody who's HIV-positive you're going to get HIV, and that rarely occurs," Tyndall said.
"A lot of these cases are people who are on treatment or cases where a condom's been used — and people have been convicted for aggravated sexual assault when the risk of them transmitting the HIV virus was essentially zero."
In their statement, the doctors say that being spat on by an HIV-positive person poses no possibility of transmission, and being bitten by an infected person can't spread the virus unless the skin is broken and the person's saliva contains blood. But even in those instances, the possibility of contracting HIV is negligible, they say.
"We have seen that the criminal law is being used in an overly broad fashion against people living with HIV in Canada, in part because the science is not well understood or communicated," co-author Dr. Mona Loutfy, a clinician-scientist at Women's College Hospital in Toronto, said in a release.
"It was time for experts to let the justice system know, clearly and concisely, what science tells us about HIV and its transmission."
The physicians also stress that dramatic treatment advances — primarily the advent of antiretroviral therapy — have transformed HIV into a chronic but manageable condition, no longer the automatic death sentence that it once was.
Their statement, endorsed by the Association of Medical Microbiology and Infectious Disease Canada, was welcomed by a number of advocacy organizations, including the Canadian HIV/AIDS Legal Network.
Executive director Richard Elliott said the law as it stands "really needs to be reined in" because it treats people as rapists — one of the most serious offences in the criminal code — for not disclosing their HIV status.
"We say this is a wild overreach and a misuse of the criminal law because what you see is people who had no harmful intent, who posed no realistic possibility of transmitting HIV, being convicted of aggravated sexual assault and sentenced in some cases to years in prison and designated for life a sex offender.
"That is not right. The law needs to be pulled back," said Elliott, adding that Crown prosecutors should exercise more restraint in pursuing cases where the circumstances aren't warranted.
"And we need to see judges have a better understanding, including obviously our Supreme Court judges, of the science and of the importance of drawing the line in a more conservative and restrained place."
That's not to say that there is never a case for laying charges for non-disclosure.
UNAIDS and other international bodies have said that if someone transmits HIV intentionally, "that's a circumstance in which criminal prosecution could be legitimate," he said, noting there have been a handful of such cases in Canada.
Tyndall said the issue of non-disclosure between sexual partners is mostly a public health issue, but the current law has "wreaked havoc" with efforts that encourage people at increased risk of infection, such as those in the gay community, to get tested for HIV.
Fear of possible prosecution has meant some people have chosen not to learn their HIV status, "because if they don't know, then they can't get charged," he said.
"The basic idea is that this is a public health problem and it's not a criminal justice problem. And I don't think it belongs in the court system at all."
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