Hanoi - The UN's top health rights official called Tuesday for the decriminalization of drug use and an end to mandatory drug rehabilitation camps in Asia, which he said amounted to "keeping sick people jailed."

Anand Grover, the UN Special Rapporteur on the Right to Health, made the call at a conference on international health rights in Hanoi.

"The criminalization of these practices actually hinders the right to health of all persons," Grover said. He denounced the practice by many Asian states, including China, India, Malaysia and Vietnam, of compelling drug addicts to detoxify in mass treatment camps.

There are over 50,000 inmates of mandatory drug treatment camps in Vietnam, and up to 350,000 in China, according to the Open Society Institute.

Heroin addicts who detoxify in rehabilitation camps have relapse rates exceeding 90 per cent. Most scientific experts now advocate oral substitution therapy with drugs such as methadone and buprenorphine, which eliminate the craving for heroin.

But many countries are reluctant to embrace such therapy, which they consider substituting one drug dependency for another. In Vietnam, heroin addicts are sent to mandatory rehabilitation centers for up to four years.

Several Vietnamese experts at the conference said their country was gradually moving away from the treatment center approach and embracing substitution therapy. The country's 2007 law on AIDS adopted a so-called "harm reduction" approach to drug addiction, rather than focusing solely on detoxification.

A pilot program of Vietnamese methadone clinics began operating in April 2008. Six methadone clinics now serve 1600 former heroin addicts in Haiphong and Ho Chi Minh City, funded with grants from the US PEPFAR anti-AIDS program.

About 95 per cent of those receiving methadone have stuck with the program, said Dr Nguyen To Nhu, Vietnam program director of Family Health International, which helps run the clinics.

Dr Le Giang, a Vietnamese researcher who has studied the clinics, said the failure of detoxification at treatment camps often led to a fatalistic belief that quitting heroin was impossible.

"Many families, and even drug users themselves, completely lost their faith in treatment," Giang said. He said many users had been inspired by the ability of methadone to restore their "ownership of their own bodies and lives."

Giang said there was "much more openness, from the top level to the community level, to talk about [methadone treatment], but there's still a long way to go." (dpa)