In a follow-up to an earlier story, the Norwegian Institute of Public Health, or Folkehelseinstituttet, announced additional cases of botulism among intravenous drug users in the Oslo area (computer translated).

Public domain photo/Psychonaught
Public domain photo/Psychonaught

Health officials were notified of two additional cases of clinically probable botulism in people who had injected heroin outside the veins. This follows the first case, which was reported at Christmas time. It is important to increase awareness of possible contaminated heroin may be in circulation.

This brings the total to 3 cases since late December. In all cases the heroin obtained in the drug environment in Oslo, health officials note.

Related: Scotland health officials investigate two additional heroin-linked botulism cases

Most people with injection drug-associated botulism are users of so-called “black tar heroin”, a specific preparation of heroin.  Risk is also higher for those who inject the drug directly into tissues, as opposed to veins (skin popping).

Black tar heroin is a thick gummy substance and because of this it needs to be diluted. Many experts believe the source of the botulism is in the “cutting agent” which is believed to be things like dirt and honey.

Wound botulism is one of five types of botulism (foodborne, infant, Adult intestinal toxemia and  iatrogenic botulism are the other four).

Related: Oslo woman dies from Naegleria fowleri, linked to daily nasal washing with tap water

Wound botulism occurs when spores of Clostridium botulinum contaminate a wound, germinate and produce botulinum neurotoxin in the body. Most wound botulism cases have been among intravenous drug users.

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