Pneumonia of atypical measles.

Infection with rubeola virus after previous immunization with killed measles virus vaccine produced abnormal chest radiographs in 9 patients. Variable pneumonic consolidation occurred in all cases and was mainly lobar or segmental in distribution. Four patients had hilar adenopathy, 3 pleural effusion, and in 1 instance a pulmonary nodule remained 9 months after clearing of the acute pneumonia. Atypical measles pneumonia is a presumed hypersensitivity response in incompletely immunized patients.