The medical cost of ragweed allergies is skyrocketing: between 59 million and 186 million euros per year. The authorities are now trying to contain this invasive and highly allergenic exotic plant, imported into France in the 19th century.
Auvergne-Rhône-Alpes is particularly affected by this scourge, whose massive arrival of pollen took place on August 11 this year. It extends over “a period of one month, that is to say until the first half of September”, indicates Hervé Bertrand, environmental health technician at ARS Auvergne-Rhône-Alpes and regional referent on ambrosia.
Rhinitis, conjunctivitis and itching
“The problem is that it’s a plant that is in the process of flowering and if we don’t cut before, there will be pollen, seeds, so the ideal is to cut to prevent the pollen becomes allergenic (makes you allergic)”, explains Gabriel Freire, team leader in the road department of the Rhône department, in charge of mowing.
Rhinitis, conjunctivitis, itching: “What is typical of ragweed allergy is that it generates a much higher risk of asthma. We are not on a little hay fever, ”warns Hervé Bertrand. Allergist at the Clermont-Ferrand University Hospital, Daniela Muti explains that her pollen “even at low concentrations, gives significant symptoms”. Symptoms that would degrade the quality of life of patients, even putting that of asthmatics in danger if nothing is done.
10% of the population allergic to ragweed
Hervé Bertrand reports 10% of the population allergic to ambrosia in infested areas. The latter can even reach more than 25%, and the number of allergic people could still grow with the increase in CO2 in the atmosphere, reaching up to 10 million in 2041-2060, according to scientists.
The departments most affected by the problem of allergies to ragweed pollen are Rhône, Ain, Drôme and Isère: “It is a plant which has spread via road works and which has a great ability to settle in field crops. The east of Lyon met all the conditions that facilitated its installation,” says Hervé Bertrand. Less infested but closely monitored, other departments are called “front areas”, such as Haute-Loire, Cantal, Charentes or Côte d’Or. “The objective is twofold: to limit the quantities of pollen for the areas of infestation, rather by crushing or mowing, and to prevent its spread in the front areas by uprooting”, affirms Hervé Bertrand, assuring that this fight is of interest to everyone. the world: communities, businesses and individuals.
Prefectural decrees to force its destruction
From the beginning of spring until the end of July, before flowering, uprooting campaigns are organised. Certain prefectural decrees make its destruction mandatory and a reporting platform has been set up. An uprooting operation that has proven its worth since the president of the association Les Jardiniers du Bourbonnais located in Vendat in the Allier department welcomes it: “We have been practicing definitive uprooting for eight years and it works, we ‘have almost more’. Only regret for Claude Grollet: that the surrounding municipalities do not do the same.
The only interest that ambrosia could represent? It is edible for sheep and goats. Eco-grazing experiments have been carried out. “It can be one of the ways of management, but it will not be enough to eradicate it”, deplores André Coppard, vice-president of the chamber of agriculture of Isère.