ZERO-TOLERANCE policing in the US has failed to stem HIV infection, drug-related deaths and increased purity of heroin, new research reveals.

A joint study between New York and Sydney researchers shows HIV-infection rates among drug users and their children are much higher in the US than Australia.

The study tracked 16 drug users in New York and Sydney over three years. Half of the 16 New York participants had died by the end of the study but only one Sydney participant, which was attributed to an overdose.

"HIV infection in IDUs, their sexual partners and children is now the driving force behind the epidemic in North America," researchers Lisa Maher, from the University of NSW, and Bruce Johnson, director of the Institute for Special Populations Research, said in the Medical Journal of Australia, released today.

"Despite adopting a hardline 'zero-tolerance' approach to illicit drug use . . . the US has experienced increases in heroin purity, drug-related deaths, drug-related hospital emergency room presentations and AIDS cases relating to injecting-drug use.

"By contrast, Australia's approach, characterised by pragmatism, tolerance and bipartisan support for harm reduction, has achieved considerably better outcomes."