The prevalence of hay fever has been surging for decades and this is likely to continue—a change so fast that genetic and health changes can’t be solely responsible. Improved hygiene, the widespread use of antibiotics and antiseptics, lifestyle changes, diet, pollution, and the climate crisis are also thought to play a major role in this increase.

But now there is new hope for sufferers. As proof-of-principle, researchers have engineered an antibody from mice, which, when applied to the inside of the nose, stops mice from developing hay fever and asthma symptoms in response to mugwort pollen. Mugwort is the most common cause of pollen allergies in central Asia and parts of Europe, where between 10% and 15% of people with hay fever are allergic to it.

The study has been published in Frontiers in Immunology.