In the spring of 2004, the Chinese health authorities gave ALK-Abelló the approval to market its injection-based vaccine Alutard SQ^® against house dust mite allergy in China. So far, more than 30 allergy centers have been opened at hospitals in the largest Chinese cities, and in September 2005, ALK-Abelló opened a research center in Guangzhou. These centers have been warmly welcomed by specialists, patients and the authorities. House dust mites are the main cause of allergy in China.