"然后再过2,3年,就开始跟本地人一样容易过敏,眼角痒啊,打喷嚏,流鼻涕什么得毛病都出来了。" == Hay Fever
Most people end up taking medication, not 短期, this happens to many of my friends. No cure, unless ? or something different, then 做手术. "打预防针", never heard of this. Some Chinese doctor(s) claim they can cure it, I'm not sure.