The 2026 Australian pollen season has started, with some people in the eastern states reporting their hay fever symptoms have begun earlier than normal.

Compared to last year, satellite imaging suggests eastern states have experienced more vegetation growth during late winter and early spring.

Meanwhile, Western Australia has lower levels of plant growth, likely due to lower than usual rainfall. This may mean a slower start to the pollen season.

Plant growth is an important predictor for pollen season severity, as greater growth can lead to earlier flowering and increased pollen production. Spring rainfall over the next few weeks will also be crucial in determining the severity of the pollen season.

How does pollen cause hay fever symptoms?

Pollen is produced as part of a plant’s annual reproductive cycle. Male flowers produce pollen, which is distributed to female flowers by insects, birds and the wind.

When the wind disperses pollen grains, they can travel great distances in the air, and when we breathe in, we can inhale them. Once in the nose, eyes and lungs, proteins on the surface of the pollen, and small pollen fragments, interact with our cells.

In people with pollen allergy, this can trigger an immune response that causes hay fever symptoms, including sore and itchy eyes, sneezing and coughing.

When pollen enters the lungs, it can also trigger asthma attacks. This is more likely to occur during thunderstorms, when changes in air pressure and humidity cause pollen grains to rupture. Fragments........

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