Botulism cases in Europe following medical interventions with botulinum neurotoxin
Since late February 2023 and as of 10 March 2023, 67 cases of botulism linked to intragastric injection of the botulism neurotoxin (BoNT) have been reported in Germany (12), Austria (1), Switzerland (1) and Türkiye (53).
The information currently available indicates that all patients had medical interventions aimed at helping them lose weight, performed between 22 February and 1 March 2023. Among 63 cases with available information, 60 cases are linked to a private hospital in Istanbul while three cases are linked to a private hospital in Izmir, Türkiye.
The symptoms have ranged from mild to severe and several cases have been hospitalised. Among those hospitalised, a number are reported to have been admitted to Intensive Care Units (ICU) and received treatment with botulinum anti-toxin.
Individuals who have travelled to Istanbul and Izmir for intragastric BoNT treatment between 22 February and 1 March 2023 are encouraged to seek medical advice from their healthcare provider, particularly if they experience symptoms such as weakness, difficulty in breathing and/or swallowing.
ECDC strongly encourages EU/EEA citizens to avoid intragastric treatments with BoNT for obesity in Türkiye as this is currently associated with a significant risk of developing botulism. At this time, it is unclear whether this event represents a therapeutic or procedural issue in the involved hospitals, or whether there is a problem with the product administered.
Investigations carried out by Turkish authorities revealed that licensed BoNT products were administered in the treatments but that these products are not approved for the treatment of obesity by intragastric injection. Consequently, the relevant departments of both hospitals have had their activities suspended, and investigations have been launched against the parties involved.
Botulism is a serious neuroparalytic illness caused by BoNTs mainly produced by the bacterium Clostridium botulinum. The disease naturally occurs in four different forms:
- food-borne botulism, caused by eating food containing BoNTs
- intestinal botulism, when botulinum spores germinate within the intestine of adult persons
- within the intestine of babies under one year of age (infant botulism)
- wound botulism, when a wound gets infected by botulinum spores.
There are two other forms of botulism which do not occur naturally: inhalation botulism and iatrogenic botulism, of which the latter may occur as an adverse event following the administration of BoNTs for therapeutic or cosmetic reasons.
While it is considered rare, individuals receiving BoNT injections for cosmetic purposes (for example, for facial wrinkle lines) or therapeutic treatments (for example, management of muscle spasticity), may develop botulism if they are injected with an excessive dose of the BoNTs.
Symptoms of iatrogenic botulism include weakness and fatigue. Toxicities following cosmetic treatment can include blurred vision, drooping eyelids, difficulty in swallowing, and dry mouth, while toxicities following therapeutic treatments include difficulty in breathing, indicating an administration of an overdose.
The symptoms of botulism can be very severe requiring intensive-care treatment as well as the administration of botulinum anti-toxin. Even when such treatments are available, complete recovery usually takes weeks to months. Limited information is available quantifying mortality in botulism cases caused by medical interventions. For food-borne botulism, 5–10% of cases are fatal.
Further information about botulism can be found on the websites of ECDC, US CDC, and WHO.
