Featured Research

from universities, journals, and other organizations

When Should Flu Trigger A School Shutdown?

Date:
November 6, 2009
Source:
Children's Hospital Boston
Summary:
As flu season approaches, parents around the country are starting to face school closures. But how bad should an influenza outbreak be for a school to shut down? A study by epidemiologists tapped a set of Japanese data to help guide decision making by schools and government agencies.

As flu season approaches, parents around the country are starting to face school closures. But how bad should an influenza outbreak be for a school to shut down?

A study led by epidemiologists John Brownstein, PhD, and Anne Gatewood Hoen, PhD of the Children's Hospital Boston Informatics Program, in collaboration Asami Sasaki of the University of Niigata Prefecture (Niigata, Japan), tapped a detailed set of Japanese data to help guide decision making by schools and government agencies. The analysis was published by the Centers for Disease Control and Prevention in the November issue of Emerging Infectious Diseases.

"Currently many U.S. schools don't have specific or consistent algorithms for deciding whether to shut down," says Brownstein. "They don't always use quantitative data, and it may be a political or fear-based decision rather than a data-based one."

Sasaki, Hoen and Brownstein analyzed flu absenteeism data from a Japanese school district with 54 elementary schools. Tracking four consecutive flu seasons (2004-2008), they asked what pattern of flu absenteeism was best for detecting a true school outbreak -- balanced against the practical need to keep schools open if possible.

"You'd want get a school closed before an epidemic peaks, to prevent transmission of the virus, but you also don't want to close a school unnecessarily," explains Brownstein. "We also wanted an algorithm that's not too complex, that could be easily implemented by schools."

A school outbreak was defined as a daily flu absentee rate of more than 10 percent of students. After comparing more than two dozen possible scenarios for closing a school, the analysis suggested three optimal scenarios:

  1. A single-day influenza-related absentee rate of 5 percent
  2. Absenteeism of 4 percent or more on two consecutive days
  3. Absenteeism of 3 percent or more on three consecutive days

The scenarios #2 and #3 performed similarly, with the greatest sensitivity and specificity for predicting a flu outbreak (i.e., the fewest missed predictions and the fewest "false positives.") Both gave better results than the single-day scenario (#1). The researchers suggest that scenario #2 (with a sensitivity of 0.84 and a specificity of 0.77) might be the preferred early warning trigger, balancing the need to prevent transmission with the need to minimize unnecessary closures.

"Our method would give school administrators or government agencies a basis for timely closure decisions, by allowing them to predict the escalation of an outbreak using past absenteeism data," says Hoen. "It could be used with data from schools in other communities to provide predictions. It would leave decision-making in the hands of local officials, but provide them with a data-driven basis for making those decisions."

Japan makes a good model for studying influenza in schools because it closely monitors school absenteeism due to flu, requires testing for the flu virus in students who become ill, and has a track record of instituting partial or complete school closures during outbreaks. However, Brownstein cautions that the scenarios might play out differently in the U.S. than they would in Japan, mainly because students here aren't required to be tested for influenza as they are in Japan, so it's less certain whether they actually have the flu. Also, the vaccination status of students in this study was unknown.

Last spring, during the early days of the H1N1 influenza pandemic, the CDC recommended first a 7-day school closure, then a 14-day closure after appearance of the first suspected case. Later, as more became known about the extent of community spread and disease severity, the CDC changed the recommendation to advise against school closure unless absentee rates interfered with school function. CDC's current guidelines (http://www.cdc.gov/h1n1flu/schools/schoolguidance.htm, 10/21/09) don't provide a specific algorithm, but state that "the decision to selectively dismiss a school should be made locally," in conjunction with local and state health officials, "and should balance the risks of keeping the students in school with the social disruption that school dismissal can cause." When the decision is made to dismiss students, CDC recommends doing so for 5 to 7 calendar days.

Researchers at the Harvard School of Public Health, the Boston University School of Public Health, and Niigata University were coauthors on the study. The study was funded by the Takemi Program, the Japan Foundation for the Promotion of International Medical Research Cooperation, the National Institute of Allergy and Infectious Disease, the National Institutes of Health Research and the Canadian Institutes of Health Research.


Story Source:

The above story is based on materials provided by Children's Hospital Boston. Note: Materials may be edited for content and length.


Journal Reference:

  1. Sasaki A, et al. Evidenced-based tool for triggering school closures during influenza outbreaks. Emerging Infectious Diseases, November 2009 [link]

Cite This Page:

Children's Hospital Boston. "When Should Flu Trigger A School Shutdown?." ScienceDaily. ScienceDaily, 6 November 2009. <www.sciencedaily.com/releases/2009/11/091104152302.htm>.
Children's Hospital Boston. (2009, November 6). When Should Flu Trigger A School Shutdown?. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2009/11/091104152302.htm
Children's Hospital Boston. "When Should Flu Trigger A School Shutdown?." ScienceDaily. www.sciencedaily.com/releases/2009/11/091104152302.htm (accessed September 17, 2014).

Share This



More Science & Society News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
President To Send 3,000 Military Personnel To Fight Ebola

President To Send 3,000 Military Personnel To Fight Ebola

Newsy (Sep. 16, 2014) President Obama is expected to send 3,000 troops to West Africa as part of the effort to contain Ebola's spread. Video provided by Newsy
Powered by NewsLook.com
EU Ministers and Experts Meet to Discuss Ebola Reponse

EU Ministers and Experts Meet to Discuss Ebola Reponse

AFP (Sep. 15, 2014) The European Commission met on Monday to coordinate aid that the EU can offer to African countries affected by the Ebola outbreak. Duration: 00:58 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins