Discuss as:

Visualizing hay fever

Everett Kennedy Brown / EPA

A photograph made available on April 18 shows plumes of pollen from cedar trees being carried by a gust of wind in Hanamaki city, Iwate prefecture, Japan on April 12. The pollen from cedar trees is the major cause of hay fever in Japan, a malady that affects 29.8 per cent of the Japanese population each spring.

See our slideshow of Micropollen: The beauty behind your allergy misery and follow our coverage of allergies and asthma.