In both the developed and developing worlds, it's estimated that, on average, nearly 20 % of people are affected by allergies. And in the US, asthma has become the top cause of both child and adult absence from school or work.
根據估計，無論在已開發或開發中國家，平均都有將近 2 成的人生活受到過敏疾病的影響，哮喘（氣喘）甚至已成為美國兒童無法上學和成人無法工作的最大原因。