Wu Hong / EPA

Moxibustion boxes are fixed on children's heads as they receive a traditional Chinese medical treatment as part of a 'Winter Diseases Treated in Summer' event at a hospital in Qingdao, Shandong province on July 18, 2012.

The European Pressphoto Agency reports — Moxibustion, a form of traditional Chinese medicine also called 'dong bing xia zhi', is a treatment that usually takes place during the 30 hottest days of summer. The idea is to build up hot energy (yang) at this time of year when it is at its peak in the human body; this is believed to prevent or reduce winter ailments such as tracheitis, asthma, rhinitis and rheumatoid arthritis which are said to be caused by the invasion of cold energy (yin) when yang is at a low level.

Read more about moxibustion from the American Cancer Society.

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Wu Hong / EPA

A woman blows on a moxibustion box fixed on her daughter's head in Qingdao on July 18, 2012.