Prevention of influenza in long-term-care facilities

Influenza is a frequent cause of epidemic and endemic respiratory illness in long-term-care facilities (LTCFs), resulting in considerable morbidity and mortality. Detection of influenza outbreaks in this setting can be difficult, because the clinical presentation in older adults is atypical and other pathogens also cause influenza-like illness (ILI) during the influenza season. Use of the standard case definition for influenza has not been effective in detecting episodes in residents of LTCFs. Alternative case-definitions that reflect the atypical presentation of influenza in this population have been recommended but not validated. The use of rapid tests for the detection of influenza in conjunction with more sensitive case definitions of ILI may lead to the earlier detection of influenza outbreaks in LTCFs, earlier initiation of infection control measures, and reduction in transmission. The definition of outbreak, eg, the number of episodes of ILI or episodes of confirmed influenza A that would result in the initiation of antiviral chemoprophylaxis, remains controversial in this setting. The use of newer antivirals could limit the side effects seen in older adults in LTCFs. However, annual Vaccination of residents and staff remains the most effective way to prevent the introduction of influenza A or influenza B into LTCFs. In addition, vaccination of LTCF residents reduces rates of illness and pneumonia due to influenza, as well as cardiopulmonary exacerbation, hospitalization, and death (Infect Control Hosp Epidemiol 1999;20:629-637).