The National Immunization Programme (at the time known as the Expanded Programme on Immunization - EPI) was initiated in 1979 in three districts with only two antigens (BCG and DPT) and was rapidly expanded to include all 75 districts with all six recommended antigens (BCG, DTP, OPV, and measles) by 1988. In 2003, with the support of the GAVI Alliance, monovalent Hepatitis B (HepB) vaccine was introduced, which was later administered as a single tetravalent (DPT-HepB) injection. In 2009, vaccination against Haemophilus influenzae type b was introduced through out the nation in a phase wise manner starting in Far Western (FWDR) and Western (WDR) Development Regions. Also in 2009, Japanese encephalitis (JE) vaccine was introduced into the routine immunizationprogramme in 16 JE endemic districts following JE mass vaccination campaigns. The National Immunization schedule of Nepal has included Rota viral vaccine over existing 11 Antigens.