The Escherichia coli O104: H4 epidemic which caused 40 deaths in Germany is perhaps not a problem confined to a German company, which for reasons still little known has sold contaminated sprouts to various restaurants.
Having encountered the same problem a month later in a small French village located hundreds of km away, in a batch of raw sprouts supplied by an English company requires some reflections.
The issue is becoming more serious than expected, so much so that the European Food Safety Authority (Efsa) has also activated a task force to investigate the issue and verify the causes. In a press release, EFSA specifies that the analyzes in France are still ongoing even if Escherichia coli O 104: H4 was found in two people affected by haemorrhagic dysentery.
Then there is the cultivation system of these sprouts which deserves attention because it is considered a system at risk, as it is described very well in an article by Aurelio Trevisi that we have taken up on our website. These are sprouts grown on a moist bed where the water and the environment reach critical temperatures around 30 ° C. The time-temperature combination favors the very rapid growth of any colonies of pathogenic bacteria present in the seeds or in the environment or in the water, which then remain on the sprouts if they are not sanitized correctly.
The last element concerns the reflection of some microbiologists who focus attention on the virulence of bacteria such as Escherichia coli O 157 (typically present in minced meat) or Escherichia coli O 104: H4 (found in raw sprouts) which gives habitual patrons of man have moved to the plant world.
These are microbes typical of the animal species, a part of which after some adaptations moved into plants assuming highly virulent forms for humans that cause very serious epidemics such as that of recent months in Germany.
The factors that characterize virulence are two : the production of toxins, called Shiga, capable of causing hemorrhagic diarrhea (which in some patients can degenerate into renal failure) and the ability to attach very well to the internal walls of the intestine, increasing the capacity of the bacterium to transfer toxins in the body.
A work on this topic was published a few days ago in the Lancet Infectious Diseases journal , which hypothesizes the transfer of Escherichia coli from humans (healthy carrier?) To the sprouts and then the multiplication and contamination by ingestion.
The scheme on the right proposed by the Göttingen Genomics Laboratory (right) summarizes the concept: the virulence of Escherichia coli O104: H4 derives from the combination of two strains, the first EHEC (enterohemorrhagic Escherichia coli) which produces Shiga toxins, and the second c eppo (EAEC enteroaggregative Escherichia coli) which adheres to the epithelial cells of the intestine.
Another fact to reflect on is the decision of some companies producing ready-made salads of the fourth range (intended to be eaten raw) to remove any type of sprouts from the ingredients, as a form of prevention.