Nosocomial transmission of influenza.

Influenza is a common nosocomial infection. Serious outbreaks occur typically in elderly long-term patients, but have also been reported in renal, transplant and oncology units, neonatal intensive care and paediatrics. It is likely that staff-patient cross-infection is common. Prompt diagnosis of an outbreak lies at the heart of an effective influenza control programme. This requires effective virological surveillance. There are a variety of strategies that can help to prevent spread of influenza in health care settings. Basic infection control should include isolating infected residents, restricting circulation of nursing staff between patients, and restriction of visitors. Annual influenza immunization should be offered to elderly patients, subjects with chronic disease, and those in long-term residential or nursing home care. Vaccination of health care workers has been shown to be effective in protecting elderly patients in long-term care. Use of oral amantadine or rimantadine is an additional possible strategy for prophylaxis or treatment during an outbreak.