Updated

British health authorities have warned that contaminated heroin being sold in London may cause anthrax, after one addict was hospitalized with the potentially fatal disease.

The warning follows a similar outbreak in Scotland that has infected 19 heroin addicts since December, including nine deaths. Authorities suspect the heroin or an agent mixed with the drug was likely contaminated.

"All heroin in London carries the risk of anthrax contamination," said Brian McCloskey of London's Health Protection Agency.

Anthrax is a bacterial disease that can be treated with antibiotics if caught early.

Heroin can easily become contaminated with anthrax spores while being manufactured in poor countries in Africa and Asia where the disease often infects people.