What season is prone to hay fever
USB portable air purifier can stay with us in pollen season. In northern China, there are two high seasons of hay fever every year. The first is spring, usually from early March to late May. Allergies are mainly a result of pollen from trees such as cypress and mulberry.
The second is summer and autumn, from the end of July and the beginning of August until the end of September and the beginning of October. The allergies are weed pollen, such as Artemisia japonica (Artemisia genus), Humulus japonicus (also known as Lala seedling, mulberry). In fact, autumn pollen allergies last longer and have more severe symptoms.

What does hay fever look like
Typical hay fever, the most common manifestation is allergic rhinoconjunctivitis. Its earliest symptoms are itchy eyes and red eyes, which we call conjunctival hyperemia. Then, symptoms of rhinitis soon follow, runny nose, sneezing, itchy nose, and blocked nose. In addition, sometimes itchy ears, itchy throat (that is, itchy throat), and even itchy palate may occur.
Relatively speaking, spring hay fever symptoms are milder, and the probability of asthma is only about 5%. While summer and autumn last longer (up to two months), the symptoms are more severe. Asthma may occur in 50% of patients.
How is pollen allergy different from general asthma
Asthma caused by pollen allergy is a part of typical allergic asthma. Its cause is very clear. That is allergy to pollen. The biggest difference between it and general asthma is that it has a very distinct seasonality and regionality.
Distinctive seasonality For example, asthma caused by dust mite allergy is generally perennial. But allergic asthma caused by pollen is mainly summer and autumn in Beijing. The seasonality is very obvious. While it will be “offended” when it arrives. After this period, it can be “healed without treatment”.