 KTL was merged on 1 January 2009 with STAKES, the National Research and Development Centre for Welfare and Health, to form a new research and development institute, the National Institute for Health and Welfare (THL).The last Director General of KTL was Pekka Puska, who was also appointed Director General of the THL.Initially the institute was founded to combat infectious diseases and to make and distribute serum preparations and vaccines.