Recent trends in new HIV infections and AIDS-related mortality can only show part of the story of the AIDS response. Epidemic transition metrics have been developed by UNAIDS and its partners as measures that countries can use to better track their progress towards ending AIDS as a public health threat.
One such metric, the incidence–prevalence ratio, uses the number of new HIV infections and the number of people living with HIV within a population. An epidemic transition benchmark of 3.0%—three HIV infections per 100 people living with HIV per year—corresponds to an average life expectancy after infection of 30 years. At this average life expectancy, the total population of people living with HIV will gradually fall if the country is below the 3% benchmark. The 3.0% benchmark thus combines two desirable conditions: long, healthy lives among people living with HIV and reductions in new infections.
The global incidence–prevalence ratio has declined from 11.2% in 2000 to 6.6% in 2010 to 4.6% in 2018, showing that important progress has been made against the HIV epidemic. Despite this, the world is not yet on track to end AIDS as a public health threat by 2030.
