A new study says that reduced access to HIV services during the early COVID-19 lockdowns in British Columbia was linked to a "sharp increase" in HIV transmission among some drug users.

The study conducted by researchers at the University of British Columbia says that while low social interaction during the March and May 2020 lockdown helped limit HIV transmission, it probably did not "outweigh" the increase caused by reduced access to services.

The study, published in The Lancet Regional Health journal, found that fewer people started antiretroviral therapy or took viral load testing under lockdown, while visits to overdose prevention services and safe consumption sites also declined.

The total number of new HIV diagnoses in British Columbia has been declining for decades. But Dr. Jeffrey Joy, the lead author of the report published on Friday, said he found a "surprising" increase in transmission among some drug users during the lockdown.

Joy added that transmission rates for such individuals had been relatively stable for about a decade before.

The researchers said that the sudden rise among "selected groups" could be attributed to a combination of factors, including housing instability and declining trust, which increase barriers for many people who usually receive HIV services.