Nosocomial versus iatrogenic. Doctors may aggravate illness. But ancillary caregivers can also cause a lot of trouble. Some efficiency expert in hospital where I worked had idea that labor would be saved by no longer washing sheets on medical and surgical wards. So heavily fecally soiled sheets were thrown down the laundry chutes, and it was several years before some genius discovered that fecally coated laundry chutes were blasting bacterial aerosols into wards every time chutes were used.