Guidance

Food botulism: outbreak in France involving British nationals

Urgent public health message: UKHSA has been notified about an outbreak of food botulism in France involving a small number of British nationals.

The outbreak has been traced to home-prepared sardines in oil served at a restaurant in Bordeaux, France, called the Tchin Tchin Wine Bar. French public health authorities have identified at least 29 people who ate the implicated food, which was served to customers between 4 and 10 September.

Contact has been made with several individuals across various countries in Europe, the US and Canada. Cases range from being asymptomatic to more severe illness and there has been one death so far. The French reference laboratory has identified the sardines as the source of C. botulinum neurotoxin type B and several clinical cases have been microbiologically confirmed with C. botulinum type B.

Three individuals have returned to England and are being treated here.

However, there may be more people now in the UK who ate at the restaurant whom the French authorities have not been able to trace. Warnings to the public have been issued advising any individual who ate at the Tchin Tchin Wine Bar in Bordeaux, France, between 4 and 10 September to contact their local emergency department urgently and let them know that they have visited a restaurant with a food botulism outbreak.

Food botulism is rare in the UK but is a very severe illness that can be fatal if not treated early. Foodborne botulism is an intoxication caused by ingestion of pre-formed toxin in food or a beverage. It usually occurs after ingestion of foods stored in airtight (that is, anaerobic) containers such as canned foods and homemade pickles. In foodborne botulism, vomiting and diarrhoea, followed by constipation, might precede neurological symptoms.

Incubation period

The incubation period is typically 12 to 36 hours but can be up to 7 days.

Symptoms

In foodborne botulism, gastrointestinal symptoms such as nausea, vomiting, and diarrhoea may precede neurological symptoms but are not always present.

Neurological symptoms can include:

  • disturbances to vision: blurred vision, double vision, drooping eyelids, dilated pupils
  • difficulty in swallowing and talking, slurred speech, dry mouth
  • descending muscle weakness
  • respiratory difficulty or failure due to respiratory muscle paralysis

Botulism is a toxin mediated clinical syndrome which is characterised by an acute afebrile descending bilateral symmetrical paralysis, commencing with ophthalmoplegia, bulbar and facial weakness, progressing to respiratory paralysis.

Urgent clinical actions

Patients who present with any of these gastrointestinal or neurological signs and/or symptoms and who have eaten at the Tchin Tchin Wine Bar in Bordeaux, France, between 4 and 10 September should be assessed as a suspected case of botulism.

Suspected cases should be discussed in and out of hours with the Colindale Duty Doctor via 020 8200 4400 to consider the need for treatment with botulinum antitoxin (BAT).

Diagnostic samples should be taken from symptomatic cases as below. Samples (all or any) should be sent to the Gastrointestinal Bacteria Reference Unit at Colindale by urgent courier:

  • at least 1g stool in a pot
  • at least 1g stool inoculated into Cooked Meat Broth (CMB) or other anaerobic medium
  • at least 5ml of serum taken prior to antitoxin (EDTA or haemolysed specimens cannot be tested)

Note: faeces may be difficult to obtain due to constipation, in which case 1 ml of high rectal washout in pot and 1ml inoculated into CMB can be sent.

Diagnostic laboratories should be aware that they may receive samples from patients being investigated for botulism and should ensure these are sent as soon as possible by urgent courier to the Gastrointestinal Bacteria Reference Unit at Colindale.

Transmission

Food botulism does not spread from person to person and there is no risk to the general population.

More information

For more information, see:

Earlier updates were published by Public Health England.

Published 14 September 2023