Understanding the science of HIV is crucial for shifting HIV prevention from a criminal justice-centric to a public health approach, University of Manitoba assistant professor Dr. Davinder Singh told seminar participants at Robson Hall on October 16, 2019.

Human immunodeficiency virus is transmitted when a person comes in contact with body fluids from an infected person. This can be through exposure to their blood, mother-to-infant transmission and, most commonly, sexual intercourse. The risk of transmission during penile-vaginal sex is 1 in 1,250 and for penile-oral sex it’s 0-4 in 10,000, which is negligible. The risk of transmission in penile-vaginal sex is dependent on the viral load, which is the concentration of the virus measured by the number of copies of the virus per millilitre of blood. Anti-retroviral therapy (ART) can effectively reduce viral load to an undetectable level after six months of therapy. For every ten-fold decrease in the concentration of virus, the risk of transmission drops by 2.5%. An HIV-positive person with a viral load of less than 200 copies per millilitre of blood presents no risk of transmission.

In R v. Cuerrier, the Supreme Court ruled that the defendant’s failure to disclose his HIV status constituted fraud. The only science considered by the court was condom use, no consideration was given to ART and viral load. This decision laid down the rules that non-disclosure may result in “significant risk” to an HIV-negative partner and that actual transmission was not required for the charge of non-disclosure to succeed. In R v. Mabior, the Manitoba Court of Appeal ruled that there was no obligation to disclose if viral load is undetectable or a condom was carefully used. The court considered research on condom use having an 80 per cent success rate and that having an undetectable viral load eliminates the risk of transmission. On appeal, the Supreme Court adopted a different position and stated that disclosure is required where there is “possibility” of transmission. The justices misunderstood the science – they misinterpreted a scientific research paper and the expert testimony of a doctor regarding viral load and condom use. The court therefore raised the threshold of non-disclosure to a compound requirement of undetectable viral load and condom use. “There was a fundamental lack of understanding regarding the significance of undetectable viral load in HIV transmission,” Singh said. Subsequent cases have wrongly relied on the compound requirement set out in Mabior.

Criminalization should be restricted to intentional and actual transmission of the virus, Singh said. Addressing HIV as a public health issue would reduce the discrimination and stigmatization of HIV-positive people. A public health approach using the Upshur principles for justification of public health intervention would ensure that criminal and other laws are built on these four conditions:

  • preventing harm;
  • adopting the least restrictive means;
  • imposing the burden of reciprocity on the state to cover medication and transportation costs, ensure access to immediate counselling and free condoms etc.; and
  • transparency such that all stakeholders participated in the decision-making process.

Singh concluded that “we need to stop treating HIV differently than other sexually transmitted infections with similarly significant risks and consequences.”



Are there instances where ART is not effective?

In some instances, the virus is resistant but there are strategies to counter resistant strains.

What do you think should be done to curb HIV discrimination and stigmatization?  

Efforts should be targeted at improving the conditions of people living with HIV and eradicating stigmatization tied to knowing one’s HIV status. The perception of HIV as a death sentence must also be eradicated and the public should be educated that sexual intercourse with HIV-positive partners is possible.

Should there be a role for the criminal justice system in HIV prevention?

A public health approach is more effective. The role of the criminal justice system should be de-emphasized although there is still the need to have some framework in extreme cases where a person maliciously transmits the virus.

Listen to podcasts from seminars in this series.