Navigation Links
When should flu trigger a school shutdown?

Boston, Mass. -- 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 (, 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.


Contact: James Newton
Children's Hospital Boston

Related medicine news :

1. Mark McGwires Message: Cheat, Do Drugs, Cover Up When Congress Investigates, Says Ex-White House Drug Spokesman Bob Weiner; World Series Should Test Both Teams During Games
2. Should noninvasive ventilation be considered a high-risk procedure during an epidemic?
3. How should mental, neurological and substance use disorders be treated where resources are scarce?
4. K-State Veterinarian Says Owners Should Count How Many Calories Their Obese Pets Take In And Consider Several Factors When Feeding Pets For Good Health
5. National Health Care Reformers Should Pay Attention to Lawsuit Alleging that Nations Largest Insurer Routinely Denies Liver Transplants
6. Nurses Should Be Included In Health Care Debate
7. World Vision Says Asian Disasters Should Be Wake-Up Call For Global Leaders
8. Mental Illness Awareness Week: What You Should Know, Including PBS Broadcasts, Oct. 4-10
9. Breast milk should be drunk at the same time of day that it is expressed
10. Researchers believe hormone therapy should not be stopped prior to mammograms
11. Medicinal products susceptible to dose dumping should be fully tested
Post Your Comments:
(Date:11/24/2015)... ... , ... Young patients with a wide variety of dental needs can now ... Lele, who are pediatric dentists in Tucson, AZ . Unlike traditional treatment options ... causes minimal discomfort and bleeding to the patient during treatment and the following recovery ...
(Date:11/24/2015)... ... November 24, 2015 , ... ... Black Friday sale a week early, offering 40% off select bras and underwear ... apparel industry through both mobile fit technology and the latest fashion, quickly becoming ...
(Date:11/24/2015)... ... November 25, 2015 , ... Catalent Pharma Solutions, the ... consumer health and global clinical supply services, today announced that Dr. Christine Milligan, ... East Asia Conference, to be held at the InterContinental Seoul COEX Hotel, Seoul, ...
(Date:11/24/2015)... ... November 24, 2015 , ... ... when it comes to several aspects of orthopedic care. They have received recognition ... surgeries and general orthopedic care. , Becker's Hospital Review selected hospitals for ...
(Date:11/24/2015)... , ... November 24, 2015 , ... It takes only ... a business, it is critical that the first impression be positive and reflects business ... not likely to buy anything or want to return. They will also share their ...
Breaking Medicine News(10 mins):
(Date:11/24/2015)... November 24, 2015   ... dietician deliver s advice and insights on ... More than 50% of Dubai ... healthy according to the DHA   femMED launches comprehensive solutions ...    Dubai residents are not consuming enough to ...
(Date:11/24/2015)... Nov. 24, 2015 Abaxis, Inc. (NasdaqGS: ... and consumables for the medical, research, and veterinary markets ... Financial Officer, will present at the 27 th ... 2015 at 11:30 a.m. ET. The conference will be ... New York City . Abaxis, ...
(Date:11/24/2015)... Edelris announce today that they have out-licensed to ... UCBL and ENS-Lyon on a new treatment to cure Hepatitis ... B virus (HBV) infection is a major public health problem ... to 40% of them being at risk of developing chronic ... an effective preventive vaccine, the HBV infection is still rampant ...
Breaking Medicine Technology: