Which age group is targeted in the catch up vaccination strategy of WHO for elimination of measles?

WHO'S measles elimination strategy comprises three prong approach to vaccination: catch up, keep up and follow up. Catch up is defined as one time nation-wide vaccination of all children between 9 months to 14 years regardless of history of measles or vaccination status. Keep up is defined as as routine services aimed as vaccination of more than 955 of successive bih cohos. Follow up is defined as subsequent nationwide vaccination campaign conducted every 2 to 4 years targeting all children born after the catch up campaign. Ref: Park 21st edition, page 137 Chapter: Epidemiology in communicable diseases.