We thought we had finished with hay fever … but allergy sufferers have not finished suffering, it seems. Summer is now rhymes with another threat: Ambroisie. This plant, described as “health nightmare” by Release 3 days ago, continues his disturbing progression in France, aggravating the allergic symptoms of millions of people.
An invasive plant with devastating effects
Originally from North America, Ambroisie à Sage d’Armoise (Ambrosia Artemisifolia) is today a major invasive species in Europe. Two other species – Trifide Ambroisy and Ringdom with smooth ears – are also the subject of close surveillance by the Observatoire des Ambroisies.
“Ambrosia grows on the roadside, the vague land, the projects and even the cultures. Its extremely allergenic pollen is released massively between August and October” Specifies Dr Gérald Kierzek, medical director of True Medical. And a single plant can produce several million pollen grains, capable of being transported by the wind over tens of kilometers. “”In other words, even in town, we are not immune. “
An explosion of allergy cases
According to Dr. Kierzek, the situation is only getting worse. “”Climate change, growing urbanization and pollution are all factors that promote the proliferation of this plant and worsen its effects. ” The repeated heat waves also extend the pollen season, and the ambrosia is gradually colonizing new regions.
Today, the most affected areas are:
- Auvergne-Rhône-Alpes;
- Bourgogne-Franche-Comté;
- Nouvelle-Aquitaine;
- Occitanie.
© Observatory of Ambroisies 2025
But the threat quickly extends to the whole territory.
Stronger symptoms, but also longer
Ambroisia allergy looks like a hay fever, but more intense, notes the doctor:
- Repeated sneezing;
- Blocked or flowing nose;
- Ocular itching, red eyes;
- Persistent cough;
- Asthma attacks, sometimes serious.
“These symptoms, which appear each year at the same period, must alert. An allergic test can confirm the diagnosis” underlines Dr. Kierzek
What to do to protect yourself?
If the plant proliferates it is however possible to fight against the ambrosia, by limiting its exposure maximum. The expert reminds us of the good gestures:
- Ventilate its accommodation early in the morning, when pollen is less present;
- Avoid outdoor activities on hot and windy days;
- Wash your hair and face after an outing;
- Wear a mask and glasses in the event of a Pollinic peak.
Fighting the Ambroisie can also take the form of an action on the ground:
- Report the plants on official platforms;
- Snatch the plants detected, with gloves to avoid direct contact;
- Inform its neighbors or the municipality if the plant is identified in public areas.
A major public health issue
Indeed, faced with the progression of ambrosia, local communities have a decisive role to play. “This involves active monitoring of risk areas, including construction sites, roads or wasteland, where the plant proliferates easily” Indicates the observatory of Ambroisies. It is also essential to set up preventive mowing operations before flowering, in order to prevent the release of allergenic pollen. Finally, information campaigns with citizens make it possible to raise awareness and encourage gestures of reporting or uprooting.
Actions to be carried out urgently. On a European scale, forecasts are worrying: by 2050, the number of people allergic to the Ambroisie could double. “This plant scourge is no longer just a threat to biodiversity: it is now established as a real public health issue” concludes our expert.
To find out more or report an Ambrosia plant: consult the observatory of Ambroisies (www.ambroisie.info))