Warthin Finkeldey giant cells are seen in:

c. Measles(Ref: Nelson's 20/e p 1542-1547, Ghai 8/e p 213-214)Fusion of infected cells results in multinucleated giant cells, the Warthin-Finkeldey giant cells that are pathognomonic for measles, with up to 100 nuclei and intracytoplasmic and intranuclear inclusions.