Fewer people worldwide are getting HIV — so why are rates going up in Canada?

Fewer people are being diagnosed with and dying of HIV/AIDS around the world. But progress is uneven, and only a few countries are on track to meet global targets set by the United Nations to end HIV as a public health threat by 2030, suggests a new study from The Lancet HIV medical journal.

Between 2010 and 2021, new HIV infections decreased globally by almost 22 per cent, a decline largely driven by the progress in sub-Saharan Africa. But in Canada, the opposite is happening. In 2023, there were 2,434 new diagnoses of HIV here: a 35 per cent increase compared to the year before. The number of new cases had been on the decline between 2016 and 2020. Despite the increase in infections, fewer people are dying of HIV in Canada.

Globally, HIV-related deaths have also declined between 2010 and 2021 by almost 40 per cent, say the authors of the Lancet report, noting that's thanks to antiretroviral treatment — usually a combination of drugs that stop the virus from reproducing. Most people who take the medications daily for a few months have so little virus in their blood it doesn't show up in tests and can't be transmitted to others.

"The biggest takeaway is, progress is possible, but it will require sustained focus," said Austin Carter, a research scientist at the Institute for Health Metrics and Evaluation at the University of Washington and one of the authors of the study.

The most dramatic improvements in both diagnoses and deaths were in sub-Saharan Africa. But the region still leads the world in mortality rates. "Some patients get tested too late, and HIV testing is not free countrywide," said Dr. Gertrude Komoyo, who works with Doctors Without Borders to care for patients with advanced HIV in Bangui, Central African Republic.

Canada is not the only country experiencing increasing HIV infections. It's a pattern other wealthy countries are also seeing, say researchers. 

"The story in high-income countries is that it's challenging to eliminate HIV," said Carter.

He says the numbers reflect a growth in high-risk populations — including men who have sex with men and those who inject drugs — as well as a declining interest in HIV care. 

Almost 40 per cent of the new diagnoses in Canada were after exposure to heterosexual contact; 36 per cent involved exposure to male-to-male sexual contact; 18 per cent involved injection drug use.

"The problem is that we forgot," said Dr. Rejean Thomas, who saw the worst ravages of the AIDS crisis in the 1980s at his clinic in Montreal's Gay Village.

At that time, he says, most of the patients with AIDS that he saw died within a year. Now, he's following patients who are growing old with the virus.

"I say some days, I'm doing geriatrics," Thomas said.

"In the '80s, it was a new disease killing people. No treatment. Now we have treatment. It's a chronic disease, but it's more difficult to do education and prevention." 

Prevention includes self-testing, and taking a daily pill — known as PrEP, or pre-exposure prophylaxis — which substantially lowers the risk of contracting HIV.