What are the causes of allergic rhinitis with asthma?

Rhinitis is a common disease, and the onset of allergic rhinitis is often related to some allergic factors in life. Therefore, the specific causes of allergic rhinitis accompanied by asthma in people can be understood from the following aspects.

1. Pollen

There are different kinds of pollen in the air in each season. Pollen can be wind-borne or insect-borne. Wind-borne pollen is the main cause of asthma, and the particle diameter is between 17 and 58 microns. The allergenic pollen in North America is mainly ragweed pollen, and about 20 different allergen components have been found in this pollen. In northern China, autumn pollinosis is caused by plants of the Asteraceae family, and there is a high probability of cross-allergens. In Shanghai, China, spring pollinosis is mainly caused by pollen from poplar, mulberry, French sycamore, maple, etc., while in autumn it is caused by pollen from ragweed, castor, and Artemisia.

2. House dust

House dust is composed of many components, including animal dander, fungi, bacteria, pollen, animal and plant fibers, etc. It is generally believed that the main allergen in house dust is dust mites. For those who have respiratory allergy symptoms in all seasons, the allergic effect of house dust should be paid more attention.

3. Mites

There are more than 5,000 species, and the main allergens are house dust mites and air dust mites. Dust mites are distributed all over the world and mostly breed in human living environments. The optimal temperature for dust mites to survive is around 25°C and the relative humidity is 75% to 80%. Asthma often occurs in spring and autumn, which is consistent with the seasonal changes of dust mites. The incidence of allergies to dust mites is higher in children than in adults, and higher in men than in women.