Kafunshō

is a type of hay fever that has specific causes and effects in Japan. Shortly after World War II, reforestation policies resulted in large forests of only "sugi" trees. These trees become competitive with each other and produce large amounts of pollen. This pollen is a major source of this allergy for people in Japan. Some people in Japan get medical laser therapy to stop the parts of their nose that are sensitive to pollen.

Sources

* [http://blues-tea-cha.blogspot.com/search/label/health Revenge of the Trees]
* [http://www.whatreallyworks.co.uk/start/articles.asp?article_ID=1318 What Really Works - Hay Fever]