Chance or fungus, five deaths in a village in Mon raise questions

Mystery or chance? Between 2007 and 2022, five residents of two streets in a village in Somme contracted Charcot disease. A situation echoing the excessive mortality of a village in Montchavin, Savoie, observed in 2009. The enigma was finally solved in 2021 after ten years of investigation.

In the medical world, a concentration of pathology is called a cluster – an epidemic focus in French – if Charcot disease, also called amyotrophic lateral sclerosis (ALS), is not an epidemic. In fact, it is a neurological disease that causes progressive paralysis of the muscles and usually causes death within three years.

“It’s the law of probability”

This cluster, in any case, has been much talked about ever since Picard Courier Presented the concern of the mayor of the community of Saint-Vast-en-Chaussy, a village of less than 500 inhabitants located near Amiens. After the deaths of these five people, Public Health France was contacted by the Hauts-de-France Regional Health Agency (ARS) to “determine whether there was a statistically significant excess of diseases in the observed population”.

If this excess exists, then, as “AFP, Public Health” suggested, “it will be a question of determining whether there are one or more local causes for this group of cases, other than chance, on which it is possible to act”. . France. According to Public Health France, other “unusual” conditions of grouped cases of ALS “have been reported in Public Health France over the last ten years, at this stage it is not possible to hypothesize a common cause of the various cases”.

For Pierre-François Pradat, neurologist at Pitié-Salpêtrière Hospital (APHP) and co-president of the Scientific Council of the Association for Research on ALS (ARSLA), “the cluster phenomenon is the same. It is more common. ” “It’s the law of probability,” he explains 20 minutes. If you throw a handful of matches on the ground, some may end up in a small pile. »

Beware of false morals

“The concentration in this village is not statistically significant,” adds Pierre-François Pradat, who nevertheless clarifies that the causes of this rare disease (about 8,000 new cases per year in France) are still very little known. “We know that 10% of cases are linked to genes that are now well known, but research continues on possible environmental and behavioral factors. »

In 2018, suspicions of doping were particularly raised after the announcement in Italy of the deaths of several former football players, suffering from Charcot disease. But no hypothesis could be shown on the actual causes of these additional incidences of pathology. On the other hand, some studies have actually proven that external factors can be triggers.

“In the island of Guam, for example, cases of ALS were linked to cyanobacteria,” says Professor Gwendal Le Masson, a neurologist at Bordeaux University Hospital and head of the ALS Center. And also reported a study conducted in a village in Savoie, about twelve cases of Charcot disease over twenty years: “We discovered that the culprit was the consumption of false morel, a poisonous mushroom. Here too a cyanobacteria was involved. »

For the Bordeaux professor, “the presence of the BMAA cyanotoxin in the water is an avenue to consider” in the case of the Picardy village. “Scientific studies show that pesticides, which are not used today, play a role in the appearance of this disease,” continues Gwendal Le Masson. Maybe we have to wait another ten years to get a definitive answer in Sant-Wast-en-Chausi?

Gilles Durand