Anthrax outbreak in injecting drug users

Since December 2009 there has been an ongoing outbreak of anthrax among heroin users in the UK, a number of whom have died. The anthrax is thought to be acquired from contaminated heroin.

To date, 26 cases including ten deaths have been identified; 23 in Scotland, two in England and one in Germany (which has been shown to be genetically related to the UK infections). Nine of the deaths have been reported from Scotland with the majority of Scottish cases and deaths occurring in the Greater Glasgow and Clyde region. One death from anthrax has also been confirmed in an injecting heroin user from Blackpool in North West England. The other case in England was in an injecting drug user from London. To date, no cases have been reported in Wales.

 

Anthrax is a bacterial infection caused by the organism Bacillus anthracis. The disease occurs most often in wild and domestic animals in Asia, Africa and parts of Europe although humans are rarely infected. The organism can exist as spores that allow survival in the environment, e.g. in soil, for many years. Humans generally acquire the disease through contact with infected animals or contaminated animal products. In practice anthrax almost never spreads from person-to-person.

 

There are three forms of human disease depending on how infection is acquired: cutaneous (skin), inhalation and ingestion. In over 95% of cases the infection is cutaneous, generally caught by direct contact with the skins or tissues of infected animals. Inhalation anthrax is rare and is caught by breathing in anthrax spores. Intestinal anthrax is very rare, and occurs from ingestion of contaminated meat.

 

Cutaneous anthrax can be treated and cured with antibiotics. Fatalities are often high with inhalation and gastrointestinal anthrax, since successful treatment depends on early recognition of the disease.

 

Anthrax in drug users appears to be very rare; prior to the current outbreak, only one previous case had been reported in Norway in 2000. Drug users may become infected with anthrax when heroin or the cutting agent mixed with heroin has become contaminated with anthrax spores. This could cause infection if injected, smoked or snorted.

 

More information about this outbreak for health professionals, including clinical presentation and case definitions, is available from the website of the Health Protection Agency at: http://www.hpa.org.uk/web/HPAweb&Page&HPAwebAutoListName/Page/1265637164350  and the website of Health Protection Scotland at: http://www.hps.scot.nhs.uk/anthrax/resources.aspx

 

Clinicians in Wales who suspect anthrax in any patient presenting to them should speak with their local microbiologist and contact their local Public Health Wales Health Protection Team, during office hours, or the relevant Public Health Wales on-call telephone number out of hours. Out of hours numbers are: