February 29 is the 17th International Rare Disease Day. The World Health Organization defines rare diseases as diseases affecting 0.065% to 0.1% of the total population.

In China, the "China Rare Disease Definition Research Report 2021" lists "diseases with an incidence rate of neonates less than 1/10,000" Gu Qinglong, deputy director of the Capital Institute of Pediatrics, said rare diseases in China are being diagnosed earlier and with higher detection rates. Only with early detection, early diagnosis, and early treatment can the prognosis of patients get better.