A number of deaths due to heroin use in Dublin have been linked to deaths in Glasgow, where 11 heroin users have died recently.
The Eastern Regional Health Authority confirmed that four of the five deaths in Dublin "fit the case definition" of "an as yet unidentified severe illness occurring in heroin users in Glasgow".
A total of 25 users were admitted to hospitals in Glasgow, including 17 women, the Glasgow health board said. Of the 11 who died, eight were women. Five additional people were admitted to hospitals in Stirling, Lanarkshire and Grampian.
A spokeswoman for the health board said the unidentified illness may have been brought about by injecting heroin into muscle or tissue which may have caused damage and infection, rather than into veins.
The spokeswoman said heroin users in Glasgow had been reporting unusually strong heroin which needed a large amount of acid to dissolve it. Injecting such heroin into tissue or muscle, coupled with infection, may have caused illness and death.
The Glasgow health board said tests had been carried out for possible anthrax infection but this had been ruled out almost entirely after they had shown up negative.
An article in the latest edition of New Scientist suggested the deaths in Scotland may have been due to anthrax infection after signs of such infection had been shown on the bodies of the deceased heroin users. Tests carried out in Norway on a drug addict showed up similar signs, according to the report.
The anthrax contamination could have occurred if the heroin was cut with a powder which included some material from infected animals.
The Eastern Regional Health Authority in Dublin said a European-wide alert had been issued in relation to the heroin deaths.