Thanks for the invitation. Generally speaking, when spring comes, all kinds of flowers, plants and trees bloom, and about 30% of people are allergic to these pollens. Some people have mild symptoms and do not need treatment, and they will be fine as soon as the spring passes, while some people have more severe symptoms, and appear to be unable to keep their eyes open, and have a runny nose all the time, and sneeze. The human body generally does not develop resistance, and it happens every year, which is very painful. Currently it is treated only when there are symptoms, or you can take medication to prevent it when there are no symptoms. There are also biologics that can be injected for 2 months a year and can be discontinued past the season. I hope this helps!