Health authorities in Scotland have confirmed that a second heroin user, who tested positive for anthrax, has died.
The man was being treated at Glasgow Royal Infirmary. Last week, another man with the infection died in the city's Victoria Infirmary. A woman who also tested positive is being treated at the hospital.
A fourth case of anthrax has been confirmed in Lanarkshire. The patient, who is a drug-injecting heroin user, is being treated at Monklands District General Hospital.
Anthrax is a deadly bacterial infection which occurs mostly in animals in Asia and Africa. Humans are seldom infected and it is extremely rare for anthrax to be spread from person to person.
Health specialists across the country have been reviewing recent cases of injecting drug users who have infections but no new cases have been identified.
Public health consultant Dr Syed Ahmed said: “Drug injecting is extremely risky and dangerous.
The health service deals continually with people who have suffered very serious infections due to dirty needles or contaminated drugs.
“The possible presence of a batch of heroin contaminated with anthrax makes drug injecting even riskier and even more dangerous.
“Once again, I urge injecting drug users to be on their guard and to seek urgent medical advice if they have experienced an infection or other serious symptoms.”
NHS Greater Glasgow and Clyde, the Procurator Fiscal and Strathclyde Police are trying to identify the source of the anthrax.
One possibility is that contaminated heroin, or a contaminated agent used to cut the drug, is to blame.
Heroin often comes from countries where anthrax is more prevalent in animals and bone meal, an animal product, is sometimes used as a cutting agent.
The last two known anthrax-related deaths in the UK are both of men who made drums.
In 2006 Christopher Norris (50) from the Scottish Borders, died from handling anthrax-contaminated West African drums.
Last November, 35-year-old Fernando Gomez, who is thought to have inhaled anthrax spores while handling imported animal skins, died in hospital in London.
PA