Outbreaks of 2009 pandemic influenza A (H1N1) among long-term-care facility residents - three states, 2009

Abstract

Hospitalization and death from seasonal influenza are more common among older adults and in long-term--care facilities (LTCFs). Early data from the 2009 pandemic influenza A (H1N1) outbreak indicated that attack rates among persons aged >or=65 years were lower than in other age groups, and anti-influenza A antibodies that cross-react with 2009 H1N1 could be detected in up to one third of healthy adults aged >60 years. Based on these early data and anticipation of limited initial supplies of 2009 H1N1 vaccine, the Advisory Committee on Immunization Practices (ACIP) identified priority groups for vaccination, which did not include persons aged >or=65 years who did not have higher risk for influenza or its complications. During October and November 2009, CDC received reports of 2009 H1N1 outbreaks in LTCFs in Colorado, Maine, and New York. This report summarizes the three outbreaks, which involved facilities primarily housing older patients. These outbreaks illustrate that, despite the lower risk for infection with 2009 H1N1 among persons aged >or=65 years compared with seasonal influenza, 2009 H1N1 outbreaks still can occur in LTCFs. These outbreaks also underscore the importance of respiratory illness surveillance and recommended infection-control procedures in LTCFs. All health-care personnel should be vaccinated against seasonal influenza and 2009 H1N1. LTCF residents should receive seasonal influenza vaccination, and should be vaccinated against 2009 H1N1 after assessment of vaccine availability at the local level indicates that demand for vaccine among younger age groups is being met.