“My husband was the first one on the street to get sick.” Françoise Gamain’s husband, who worked for a tire manufacturer, died in 2009, at the age of 67, from Charcot disease. “With the second patient we said it was a coincidence.”
“But after several cases, we began to tell ourselves that there were many coincidences,” he testifies to BFMTV.com.
Because in a dozen years, five people living on the same street in Saint-Vaast-en-Chaussée, a town of just over 500 inhabitants, located about fifteen kilometers from Amiens, were affected by the same disease.
Charcot disease, or amyotrophic lateral sclerosis (ALS), is a serious and severely disabling degenerative disease that causes progressive muscle paralysis. It causes the death of the patient between three and five years after diagnosis, recalls Inserm (National Institute of Medical and Health Research).
“Everything happened very quickly,” recalls Françoise Gamain. “We were diagnosed in October 2008. By the following March, he had already died.”
“A high number of cases”
The other four patients They also lived on the same street in this Somme town. A figure that draws attention: ALS affects about 8,000 patients in France, indicates the Association for Research in ALS (ARSLA). The annual incidence is 2.7 new cases per year per 100,000 inhabitants, according to the Hospices Civils de Lyon.
How to explain so many sick people in Saint-Vaast-en-Chaussée? The mayor of the town contacted the Altos de Francia Regional Health Agency (ARS). He corroborates all five cases. “The study of the report allowed ARS to confirm a high number of ALS cases in this city,” he explains to BFMTV.com.
Thus, Public Health France, responsible for ensuring health monitoring and epidemiological surveillance, was contacted. “Investigations are underway,” he assures BFMTV.com.
The agency explains that the principle of investigating “a cluster report” is to verify “whether there really is a statistical excess of diseases in the observed population.” And “if this excess exists”, to “determine if there are one or more local causes for this grouping of cases, other than random.” At the moment, no cause has been formally identified in the Saint-Vaast-en-Chaussée cases.
“The neighbors know it, the new neighbors ask me questions, I no longer know anything,” concludes the mayor, Marc Vignolle, to Courrier Picard.
“Why doesn’t this affect the other streets?”
Françoise Gamain, who has lived in Saint-Vaast-en-Chaussée since 1976, wonders. “There are fields around the house, could it come from there? From phytosanitary products? From what we ate? But if it is in the water or in the air, why? Doesn’t it affect the other streets of the town? “.
François Pradat, neurologist at the Pitié-Salpêtrière hospital (APHP) and co-president of the ARSLA scientific council, wants to be reassuring. If the situation in Saint-Vaast-en-Chaussée is “unusual”, he acknowledges, it is “statistically possible”: “ALS is a rare but not exceptional disease”.
“I have three patients who suffer from ALS and who are part of the same cycling club,” says the neurologist. “I also have couples where both partners develop ALS. This does not mean there is a link.” And he adds:
“If I had five people with ALS living on my street, I wouldn’t panic.”
A “complex” origin to be determined
The origin of the disease is “complex” to determine, reminds Inserm. The appearance of the disease would be “multifactorial”, “subject to the influence of genetics and the environment”.
In addition to the 10% of ALS with a family history, “as with all neurodegenerative diseases, there is a genetic susceptibility,” points out François Pradat. Especially because not all the genes involved in the disease have yet been identified.
“It is very likely that environmental factors influence ALS,” acknowledges François Pradat. “But you need a favorable genetic background.”
Regarding the role of the environment, “no triggering factor has been clearly identified”, although tobacco, high-level sport, exposure to pesticides, heavy metals or even a toxin present in certain algae are suspected.
In 2021, a French-American study implicated the giant gyromiter, also called false morel, in a Charcot disease cluster in Savoy. Between 1991 and 2013, some 14 cases of ALS were identified in the La Plagne-Tarentaise sector. Everyone would have eaten this mushroom.
An avenue that is being explored by François Pradat, neurologist at the Pitié-Salpêtrière hospital (APHP) and co-president of the ARSLA scientific council. “In Savoy, this cluster has not been tested,” he explains to BFMTV.com. “It didn’t really make statistical sense.”
He points out that it is still difficult to establish a group for this disease. “There are a lot of biases: the age of the population, the duration of possible exposure… We often have stories of ALS clusters, but they are rarely confirmed.”
“Where can it come from?”
In 2013, an epidemiological study published in the scientific journal Plos One on 381 patients who developed ALS in Hérault showed that the number of patients was higher in the municipalities near the Thau pond, a mussel and oyster production area, Medscape recalls.
The study implicated a toxin – BMAA – produced by cyanobacteria found in the pond. This neurotoxin had already been implicated in cases of ALS on the island of Guam, in the Pacific: BMAA was present in cycad seeds consumed by natives.
“Therefore, there is a link between BMAA and ALS,” says neurologist William Camu, head of the national competence center for (ALS) at the University Hospital of Montpellier and author of the study. By specifying that “the consumption of seafood is not the cause of the excessive incidence of ALS” and pointing out the inhalation of the toxin during sports activities around the lake, the products used by the logging industries or heavy metals contained in organisms.
In Saint-Vaast-en-Chaussée, the investigation is still ongoing. “They don’t tell us anything, we don’t have any explanation, no one has contacted us, we have the impression that no investigation is being done,” laments the daughter of one of the patients, an ambulance driver and then a secretary, who died. in 2022. at the age of 70.
“We feel completely helpless,” he continues.
Especially since his father, his aunt and his cousin still live on this street. “Where could this come from? What’s intriguing is that all of these cases occurred within a few years, or even a few months, of each other.”
Source: BFM TV
