Emergency Preparedness and Response: School Dismissals to Reduce Transmission of Pandemic Influenza

School dismissals during an influenza pandemic involve temporarily closing one or more educational facilities to students, and possibly staff, to reduce or delay transmission of pandemic influenza in schools and communities. School and public health officials decide whether to use school dismissals based on available information about the spread of infection, spectrum of illness, and perceived value of immediate action.

School dismissals can be categorized by the timing, coordination, and scale of the temporary closures in relationship to the pandemic.

• Timing describes when school dismissals are initiated. Pre-emptive dismissals take place before widespread transmission of pandemic flu has occurred either within the school system or the broader community. Reactive dismissals take place after considerable, if not widespread, transmission has occurred.
• Coordination refers to simultaneous or sequential closure of schools in a jurisdiction.
• Scale refers to the jurisdiction affected by the dismissal decision. Scale could be nation-wide, state-wide, region-wide, city- or county-wide, school district-wide, a cluster of schools, or a single school.

Summary of Task Force Recommendations & Findings

During an influenza pandemic, the coordinated closure of schools could be an important community-wide public health action. If implemented efficiently and maintained for an appropriate duration, school dismissals could reduce or delay transmission of infection; reduce the burden of illness on communities, health systems, and providers; provide time to implement additional public health actions (such as distribution of an effective vaccine); and reduce morbidity and mortality caused by the pandemic. The closure of educational facilities for the required duration, however, will involve costs to households and communities, due to social disruption and related economic effects. Against these costs, benefits from reduced morbidity and mortality (and related social and economic effects) could vary, depending on how easily the infection is spread, the severity of illness, and effectiveness of the overall public health response.

In conducting this review, the Community Preventive Services Task Force considered the available evidence regarding benefits and costs of coordinated school closures for an extended duration (weeks to months). The Task Force finding is an assessment of the overall value of coordinated school closures to the community during an influenza pandemic. Many dismissal decisions will be made locally, by school and public health officials who incorporate local considerations and information. Although the decision to close individual schools (especially schools with students at elevated risk for complications of influenza) during high or increasing rates of illness, absenteeism, or public concern remains a local option, such actions alone are unlikely to affect community-wide transmission of pandemic influenza.

The Community Preventive Services Task Force recommends pre-emptive, coordinated school dismissals during a severe influenza pandemic (a pandemic with high rates of severe illness such as that experienced in 1918) based on sufficient evidence of effectiveness in reducing or delaying the spread of infection and illness within communities. Evidence was considered sufficient based on findings from retrospective assessments of public health actions taken during the 1918 pandemic and results from modeled simulations indicating that the benefits of timely, coordinated, and sustained dismissals outweigh the expected societal and economic costs of these actions. Effectiveness of school closures during an influenza pandemic may vary with unique characteristics of the pandemic, and with the abilities of national, state, and local decision makers, health care providers, and the public to quickly implement and sustain a broader set of mitigation responses over an extended period of time (weeks to months).

The Community Preventive Services Task Force finds insufficient evidence to determine the balance of benefits and harms of pre-emptive, coordinated school dismissals in the event of an influenza pandemic of moderate or less severity (pandemics without high rates of severe illness). Evidence is considered insufficient because few studies provided information relevant to an overall assessment of potential benefits and costs of school dismissals for pandemics without high rates of severe illness. Although some studies evaluating school dismissals during the 2009 H1N1 pandemic observed lower rates of infection or illness, short term follow-up, and the absence of data on societal costs limit the interpretation of these results. In addition, level of public concern would be unlikely to support or sustain the extended duration of school dismissals (weeks to months) and the broader set of community actions necessary for meaningful reduction of levels of infection and illness within the community.

During an influenza pandemic with low rates of severe illness, social and economic costs of community-wide dismissals would likely exceed potential benefits, especially for some segments of the population, such as families in which both parents work and no other child care is available. Across pandemic scenarios with elevated rates of severe illness, the potential benefits of achievable (duration, combination, and coordination) school dismissals and community actions may be limited to slowing transmission of infection and reducing peak burden of illness on health care resources. Available evidence provides little information to inform current or future determinations of threshold parameters for school dismissal actions (characteristics of both the pandemic and the pandemic response which affect the balance of benefits to costs).

Task Force Finding & Rationale Statement

Publications

The findings and results of this systematic review have not been published.

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