HIV in Canada: A primer for service providers
The HIV treatment cascade
- The treatment cascade reflects the different services someone living with HIV needs to achieve optimal health outcomes.
- The treatment cascade is based on the successive steps that are needed for a person living with HIV to achieve an undetectable viral load.
- There are no national estimates of engagement in the HIV treatment cascade for Canada.
The HIV treatment cascade is a subcomponent of a framework for integrated approaches to HIV prevention and treatment. The treatment cascade reflects the different services someone living with HIV needs to achieve optimal health outcomes, including HIV testing and diagnosis, linkage to appropriate medical care (and other health services), support while in care, access to HIV treatment if and when the individual is ready, and support on treatment. While enhanced engagement in the cascade may have a secondary benefit of reducing HIV transmission (as a result of lower community viral load), the HIV treatment cascade does not include services for people who are HIV negative; these services are an additional component of an integrated framework.
The HIV treatment cascade has emerged as a convenient tool for assessing integrated health service delivery for people living with HIV. It is based on the successive steps that are needed for a person living with HIV to achieve an undetectable viral load. Research shows that people living with HIV who have an undetectable viral load are more likely to live long, healthy lives and are less likely to pass HIV to others. Starting from the total number of people living with HIV in a specific region (both diagnosed and undiagnosed), the successive indicators in the stages of engagement in the HIV treatment cascade are:
- total number of people living with HIV
- number of people diagnosed with HIV
- number of people linked to HIV care
- number of people retained in care
- number of people on HIV treatment
- number of people with undetectable viral load
At each stage of the cascade people may be lost to engagement and care as a result of many types of barriers, such as poor access to services; stigma and discrimination; poverty, food security and homelessness; and mental health and addictions issues. Typically only a small proportion of people living with HIV are engaged in all the steps needed to achieve an undetectable viral load. There are no national estimates of engagement in the HIV treatment cascade for Canada. In British Columbia it is estimated that 35% of people living with HIV in 2011 had made it through all of the steps in the cascade and achieved an undetectable viral load.
The HIV treatment cascade – patching the leaks to improve HIV prevention – Prevention in Focus
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