Study: The Effects Of School Closures During A Pandemic

 

 

 

# 6125

 

 

Although not without its critics, extended school closures have been promoted as one of a list of NPIs (non pharmaceutical interventions) that might be used to slow the spread of illness during a severe influenza pandemic.

 

 

The chart above, taken from the PNAS journal article entitled Public Health Interventions and Pandemic Intensity During the 1918 Influenza Pandemic, shows the excess mortality in two American cities. The tall spike represents Philadelphia, while the lower curve represents St. Louis.

 

Many researchers believe the startling difference in attack rates, and mortality, in these two cities can be explained by the way each city dealt with the outbreak.

 

In St. Louis, the Health Department closed public venues such as schools, theatres and churches very early in the outbreak, while Philadelphia did not.

 

During the spring of 2009, when novel H1N1 first began to spread, schools closures were recommended by the CDC, and by other public health entities around the world.

 

By early May it became apparent that the severity of this particular influenza virus was less than originally feared, and many public health agencies moderated their recommendations (see CDC No Longer Recommending School Closures For A/H1N1).

 

Some school districts, in the U.S., and elsewhere around the world, continued to close schools on a case-by-case basis well into the fall of 2009.

 

School closings are controversial and they do not come without some social and economic costs (see The Debate Over School Closures).

 

Critics point out that working parents rely on schools to watch their kids for much of the year during the day, and many low income families benefit from the school lunch program.

 

And of course, when schools are closed during a pandemic, some kids may congregate elsewhere and spread the virus anyway.

 

While decisions on whether to close schools during a pandemic might well be trumped by parental concerns, it is important for policymakers to get some idea of the benefits that proactive school closings would generate. 

 

To that end we’ve seen a number of studies that came out of the most recent pandemic, and while the results have not all been in alignment, many have indicated substantial benefit from school closures.

 

In a report that appeared last year in the journal Eurosurveillance (see Eurosurveillance: New Research On Pandemic Influenza), we saw several studies that attempted to quantify the benefits of school closures:

 

• Three studies out of Japan found a beneficial effect during the 2009 pandemic by using antiviral drugs and/or school closure (of varying length and timing) to interrupt its transmission.

• Conversely, a fourth study suggested that early school closures could have adversely affected herd immunity in the school environment, with lower cumulative infection rates in schools that delayed closure.

 

Last May (see NIH: School Closings Effective In 2009 Pandemic) we saw a report indicating that school closings in Mexico reduced disease transmission by as much as 37%.

 

This from the NIH.

 

Tuesday, May 24, 2011
5 p.m. EDT

Mexican flu pandemic study supports social distancing

Fogarty research published in PLoS Medicine

Eighteen-day periods of mandatory school closures and other social distancing measures were associated with a 29 to 37 percent reduction in influenza transmission rates in Mexico during the 2009 pandemic. The research was carried out by scientists at the Fogarty International Center at the National Institutes of Health and published in PLoS Medicine.

 

(Continue . . .)

 

I’ve posted on a number of other studies of the effects of school closures over the past few years, including:

 

Study: Pandemic Mitigation by Early School Closure

Study: Student Behavior During Pandemic School Closings

School Closures Revisited

 

All of which serves as prelude and introduction for a new study, just out in the Annals of Internal Medicine, that looks at the effects of school closures in Canada during the 2009 pandemic.

 

Effects of School Closure on Incidence of Pandemic Influenza in Alberta, Canada

David J.D. Earn, PhD; Daihai He, PhD; Mark B. Loeb, MD, MSc; Kevin Fonseca, PhD; Bonita E. Lee, MD, MSc; and Jonathan Dushoff, PhD

Abstract (excerpts)

Background: Control of pandemic influenza by social-distancing measures, such as school closures, is a controversial aspect of pandemic planning. However, investigations of the extent to which these measures actually affect the progression of a pandemic have been limited.

 

<SNIP>

 

Results: The ending and restarting of school terms had a major effect in attenuating the first wave and starting the second wave of pandemic influenza cases. Mathematical models suggested that school closure reduced transmission among school-age children by more than 50% and that this was a key factor in interrupting transmission. The models also indicated that seasonal changes in weather had a significant effect on the temporal pattern of the epidemic.

 

<SNIP>

 

Conclusion: Analysis of data from unrestricted virologic testing during an influenza pandemic provides compelling evidence that closing schools can have dramatic effects on transmission of pandemic influenza. School closure seems to be an effective strategy for slowing the spread of pandemic influenza in countries with social contact networks similar to those in Canada.

 

While the entire article is behind a pay wall, for more on this we can go to the press release from McMaster University.

 

School closures slow spread of pH1N1

Should be considered as a control measure during pandemic outbreaks

Hamilton, ON (Feb. 6, 2012) - Closing elementary and secondary schools can help slow the spread of infectious disease and should be considered as a control measure during pandemic outbreaks, according to a McMaster University led study.

 

Using high-quality data about the incidence of influenza infections in Alberta during the 2009 H1N1 flu pandemic, the researchers show that when schools closed for the summer, the transmission of infection from person to person was sharply reduced.

 

"Our study demonstrates that school-age children were important drivers of pH1N1 transmission in 2009," says David Earn, lead author of the study published in Annals of Internal Medicine. Earn is professor in the Department of Mathematics and Statistics and member of McMaster's Michael G. DeGroote Institute for Infectious Disease Research (IIDR).

 

Alberta was the only Canadian province to continue extensive virologic testing throughout the first wave and continuously to the middle of the second wave of the 2009 pandemic, allowing researchers to identify the causes of changes in incidence as the pandemic progressed.

"The data that we obtained were so good that our plots immediately revealed a huge drop in incidence when schools were closed for the summer," says Earn. "Using state-of-the-art modeling, we then demonstrated that transmission was reduced by at least 50 per cent."

(Continue . . . )

 

 

Although the severity of any novel pandemic virus will no doubt figure into the equation (as will the social and economic costs of shuttering schools), today’s study adds considerable weight to the notion that school closures could be an effective intervention during the next influenza pandemic.

NIH: School Closings Effective In 2009 Pandemic

 

 

 

# 5573

 

One of the most contentious issues during the opening days and weeks of the 2009 novel H1N1 outbreak was the wisdom of closing schools to reduce transmission of the virus.

 

Since the virulence of the virus was largely unknown during those opening weeks, school closures were recommended by the CDC, and by other public health entities around the world.  

 

The closing of schools, and other venues where people gather (sporting events, restaurants, shopping malls), has long been argued as being potentially an important mitigation strategy during a pandemic.

 

By early May (2009), however, it was apparent that the severity of this particular influenza virus was less than originally feared, and many public health agencies moderated their recommendations  (see CDC No Longer Recommending School Closures For A/H1N1).

 

Some school districts, in the U.S., and elsewhere around the world, continued to close schools on a case-by-case basis well into the fall of 2009.

 

In a future, more severe pandemic, the extended closing of schools will once again likely be considered to help reduce the spread of the virus.

 

It isn’t an easy decision, however.  School closings are controversial, and the issues are complex  (see The Debate Over School Closures).

 

Critics point out that working parents rely on schools to watch their kids for much of the year during the day, and many low income families benefit from the school lunch program.

 

And of course, when schools are closed during a pandemic, some kids may congregate elsewhere and spread the virus anyway.

 

 

It is important, therefore, to get some idea of the benefits that school closings would generate. To that end we’ve seen several studies over the past two years that have produced varying estimates.

 

Study: Pandemic Mitigation by Early School Closure

Study: Student Behavior During Pandemic School Closings

School Closures Revisited

Study: Effect Of School Closures On Viral Transmission

Today we’ve a new study by the NIH’s Fogarty International Center, Arizona State University and colleagues at the Mexican Institute for Social Security that appears in PLoS Medicine that looks at the epidemiology of the H1N1 outbreak in Mexico, and the effects of school closings and social distancing on its transmission.

 

Our first stop are a few excerpts (slightly reformatted) from NIH press release, which summarizes this research article nicely.

 

 

Embargoed for Release
Tuesday, May 24, 2011
5 p.m. EDT

Mexican flu pandemic study supports social distancing

Fogarty research published in PLoS Medicine

Eighteen-day periods of mandatory school closures and other social distancing measures were associated with a 29 to 37 percent reduction in influenza transmission rates in Mexico during the 2009 pandemic. The research was carried out by scientists at the Fogarty International Center at the National Institutes of Health and published in PLoS Medicine.

 

The social distancing measures implemented by the Mexican health authorities in spring 2009 were effective in reducing disease transmission by more than one-third, the study found.

 

Social distancing interventions can be implemented during unusual infectious diseases outbreaks and include school closing, closure of movie theaters and restaurants, and the cancellation of large public gatherings. Mexico implemented a nationwide mandatory school closure policy during an 18-day period in late April and early May 2011.

 

The United States implemented school closure interventions on a local basis during the 2009 pandemic, but the impact of these interventions has yet to be evaluated.

(Continue . . .)

 

 

During a particularly severe pandemic, it has been suggested that schools could be closed for up to 12 weeks. While drastic, that strategy is based – in part – on some of the experiences from the last great pandemic in 1918.

 

 

The chart above, taken from the PNAS journal article entitled Public Health Interventions and Pandemic Intensity During the 1918 Influenza Pandemic , shows the excess mortality in two American cities.

 

The tall spike represents Philadelphia, while the lower curve represents St. Louis.

 

Many researchers believe the startling difference in attack rates, and mortality, in these two cities can be explained by the way each city dealt with the outbreak.

 

In St. Louis, the Health Department closed public venues such as schools, theatres and churches very early in the outbreak, while Philadelphia did not.

 

While are societal costs to closing schools and other public venues, studies continue to show that during a severe pandemic it might very well be worth doing. 

 

Here are some excerpts from the open access article in Plos Medicine.  Follow the link to read it in its entirety.

 

 

 

Characterizing the Epidemiology of the 2009 Influenza A/H1N1 Pandemic in Mexico

Gerardo Chowell, Santiago Echevarría-Zuno Cécile Viboud, Lone Simonsen, James Tamerius, Mark A. Miller, Víctor H. Borja-Aburto

Abstract  (Excerpts)

Background

Mexico's local and national authorities initiated an intense public health response during the early stages of the 2009 A/H1N1 pandemic. In this study we analyzed the epidemiological patterns of the pandemic during April–December 2009 in Mexico and evaluated the impact of nonmedical interventions, school cycles, and demographic factors on influenza transmission.

 

Methods and Findings

. . .   We estimate that the 18-day period of mandatory school closures and other social distancing measures implemented in the greater Mexico City area was associated with a 29%–37% reduction in influenza transmission in spring 2009. In addition, an increase in R was observed in late May and early June in the southeast states, after mandatory school suspension resumed and before summer vacation started. State-specific fall pandemic waves began 2–5 weeks after school reopened for the fall term, coinciding with an age shift in influenza cases.

Conclusions

We documented three spatially heterogeneous waves of the 2009 A/H1N1 pandemic virus in Mexico, which were characterized by a relatively young age distribution of cases. Our study highlights the importance of school cycles on the transmission dynamics of this pandemic influenza strain and suggests that school closure and other mitigation measures could be useful to mitigate future influenza pandemics.

Study: Pandemic Mitigation by Early School Closure

 

 

# 4758

 

 

One of the first steps taken by many countries to reduce the spread of novel H1N1 last year was the closing of schools in affected communities.

 

By early May (2009) it was apparent that the severity of this particular influenza virus was less than originally feared, and many public health agencies moderated their recommendations  (see CDC No Longer Recommending School Closures For A/H1N1).

 

But a future, more severe pandemic, the extended closing of schools will once again likely be considered to help reduce the spread of the virus.

 

It isn’t an easy decision, however.  School closings are controversial, and the issues complex  (see The Debate Over School Closures).

 

Working parents rely on schools to watch their kids for much of the year during the day, and many low income families benefit from the school lunch program.  And of course, when schools are closed during a pandemic, some kids may congregate elsewhere and spread the virus anyway.

 

Many parents, however, would take exception to the notion of sending their kids to school during a pandemic.  Not only would it, in their estimation - endanger their children – it increases the odds of them bringing the virus home to the rest of the family as well.

 

So it is important to get some approximation of the benefits that school closings would generate.  To that end we’ve seen several studies over the past year that have produced varying estimates.

 

Study: Student Behavior During Pandemic School Closings

School Closures Revisited

Study: Effect Of School Closures On Viral Transmission

 

Today we’ve another study appearing in BMC Infectious Diseases, this time from the School of Computer Science and Software Engineering at the the University of Western Australia.

 

Here is the abstract (slightly reformatted for readability).

 

Developing guidelines for school closure interventions to be used during a future influenza pandemic

Nilimesh Halder , Joel K Kelso  and George J Milne

BMC Infectious Diseases 2010, 10:221doi:10.1186/1471-2334-10-221

Published: 27 July 2010

Abstract (provisional)

Background

The A/H1N1 2009 influenza pandemic revealed that operational issues of school closure interventions, such as when school closure should be initiated (activation trigger), how long schools should be closed (duration) and what type of school closure should be adopted, varied greatly between and within countries. Computer simulation can be used to examine school closure intervention strategies in order to inform public health authorities as they refine school closure guidelines in the light of experience with A/H1N1 2009 pandemic.

Methods

An individual-based simulation model was used to investigate the effectiveness of school closure interventions for influenza pandemics with R0 of 1.5, 2.0 and 2.5. The effectiveness of individual school closure and simultaneous school closure were analyzed for 2, 4 and 8 weeks closure duration with a daily diagnosed case based intervention activation trigger scheme. The effectiveness of combining antiviral drugs with school closure was also investigated.

Results

Attack rate was reduced from 33% to 19% (14% reduction in overall attack rate) by 8 weeks school closure activating at 30 daily diagnosed cases in a community for an influenza pandemic with R0 = 1.5; whereas combined with antivirals, 19% (from 33% to 14%) reduction in attack rate was obtained.

 

For R0 >= 2.0, school closure would be less effective. An 8 weeks school closure strategy gives 9% (from 50% to 41%) and 4% (from 59% to 55%) reduction in attack rate for R0 = 2.0 and 2.5 respectively; however, school closure plus antivirals would give a significant reduction (~15%) in over all attack rate. The results also suggest that an individual school closure strategy would be more effective than simultaneous school closure.

Conclusions

Our results indicate that the particular school closure strategy to be adopted depends both on the disease severity, which will determine the duration of school closure deemed acceptable, and its transmissibility.

 

For epidemics with a low transmissibility (R0 < 2.0) and/or mild severity, individual school closures should begin once a daily community case count is exceeded. For a severe, highly transmissible epidemic (R0 >= 2.0), long duration school closure should begin as soon as possible and be combined with other interventions.

 

 

George E. P. Box, Professor Emeritus of Statistics at the University of Wisconsin, is often credited with coining the familiar adage:

 

“All models are wrong, but some models are useful.”

 

While imperfect, we use computer models every day to try to mathematically simulate real-life events;  everything from highway traffic flow to weather forecasting.

 

The authors describe some of the limitations to their study, including:

 

As the model is based on a population in a developed country the outcomes may not be applicable to populations in a developing country, where populations may be less mobile and have higher population densities.

 

We have focused on the reduction in the number of daily symptomatic cases and the cumulative illness attack rate as they are used for determining intervention effectiveness rather than focusing on influenza-related adverse events such as hospitalizations and deaths.

 

We also do not take account of possible antiviral drug resistance [40] [41] that may arise due to the implementation of antiviral drug strategies, as our main goal is to suggest refinements to policy guidelines for school closure.

  

In this case, the authors based their modeling on a medium sized (pop. 30,000) town in Western Australia. 

 

They find a substantial reduction in the spread of a future pandemic influenza can be achieved by the (extended) closing of schools at the optimum point in the local spread of the virus.

 

Gauging when and how long to close schools, however, may require information that isn’t always immediately available.  Such as the R0 (basic reproductive number) of the virus, the CFR (Case Fatality Ratio) or, the number of people actually infected in a community. 

 

Despite the fact that life is messy, and computer models aren’t perfect at depicting it, the entire report is worth reading.

 

This is how the authors sum up their study.

Conclusions 

Our simulation results give guidance as to public health policy decisions in the refinement of school closure strategies to be used in a future influenza pandemic. We have systematically evaluated school closure operational issues to determine when schools should be closed and re-opened to achieve the maximum reduction in influenza spread.

 

We found that the optimal timing of school closure depends both on the duration of school closure (which we assume will depend on the severity of the influenza strain, with strains that are more severe in terms of serious infection outcomes making longer periods of school closure acceptable) and on the transmissibility of the influenza strain (which influences the rate of growth and spread of the epidemic).

 

Accurate early estimates of epidemic characteristics such as the basic reproduction number and disease severity are thus necessary to achieve the maximum case reduction from school closure.

 

We found that a policy of allowing schools to close individually was much less sensitive to the precise timing of the intervention than a policy of simultaneous community-wide school closure, a valuable observation given the difficulty in determining the true degree of epidemic spread in the early stages of an outbreak.

Study: Student Behavior During Pandemic School Closings

 

 

 

# 4555

 

 

One of the commonly cited concerns over closing schools during a pandemic has been the assertion that students would simply find other places to congregate, such as the mall.  

 

Gains in reducing transmission of the virus due to `social distancing’, many have felt, were over-estimated due to non-compliance to advice to stay home.

 

We’ve a study today that appears in PLoS One, which looks at the self-reported behavior of students at private girls' school in Boston that closed for a week towards the end of the school year. 

 

Grades 9-12 and grades 5-8 were sampled.   This was a small study, and subject to a number of limitations (which are enumerated in the article).  

 

Also, the severity of novel H1N1 wasn’t generally perceived by the public as a `deadly flu’.   Behaviors observed during this last pandemic may not accurately reflect behavior in future, potentially more virulent, outbreaks.

 

 

That said, here is the abstract, followed by a couple of excerpts from the discussion area of the study. 

 

The results, as you will see, are a mixed bag.

 

Social contacts continued, albeit at a lower level, once schools closed and disturbingly, many students failed to follow the advice to stay home if sick in the days leading up to the school’s closure.

 

 

Student Behavior during a School Closure Caused by Pandemic Influenza A/H1N1

 

 

Joel C. Miller, Leon Danon, Justin J. O'Hagan, Edward Goldstein, Martin Lajous, Marc Lipsitch

Abstract

Background

Many schools were temporarily closed in response to outbreaks of the recently emerged pandemic influenza A/H1N1 virus. The effectiveness of closing schools to reduce transmission depends largely on student/family behavior during the closure. We sought to improve our understanding of these behaviors.

Methodology/Principal Findings

To characterize this behavior, we surveyed students in grades 9–12 and parents of students in grades 5–8 about student activities during a weeklong closure of a school during the first months after the disease emerged. We found significant interaction with the community and other students–though less interaction with other students than during school–with the level of interaction increasing with grade.

Conclusions

Our results are useful for the future design of social distancing policies and to improving the ability of modeling studies to accurately predict their impact.

 

 

Discussion (Excerpts)

Surprisingly, interaction with other students was lower at the end of the closure than at the beginning, particularly in grades 9–11. We had anticipated that there would be an initial period of fear-based isolation followed by increased contacts as complacency grew. An explanation for the actual observations could be that families were initially unprepared for the closure and students had little to do except visit friends, but as the week progressed families planned additional activities. Alternately, the low level of contacts could represent studying at home for exams that occurred soon after returning to school.

 

The data suggest students did not closely adhere to advice from the school about behavior to control the spread of infection. Prior to the closure, students were advised to remain home for one week following onset of fever with respiratory symptoms. This was not followed, and some students attended school the day after symptom onset.

 

During the closure, students were advised to avoid contacts with other students and with the community, but our surveys show that they remained active, unless they became symptomatic. Whether it is important for apparently healthy students to avoid social contact for the entire closure is unclear: although direct evidence for or against significant presymptomatic transmission of influenza is weak [11], it is frequently assumed that a significant fraction of infections happen in the presymptomatic stage [12].

School Closures Revisited

 

 

 

#4328

 

In case anyone had any doubts beforehand, the pandemic of 2009 demonstrated that NPIs (non-pharmaceutical interventions) such as school closures, hand washing, and staying home when sick are our first line of defense during a disease outbreak. 

Vaccines take months to manufacture, and would likely remain in short supply for months beyond that.  

 

While novel H1N1 proved to be a moderate pandemic virus, with a low CFR (Case Fatality Ratio), the next global health challenge may prove far more daunting.

 

The good news is novel H1n1 afforded us an excellent opportunity to try various mitigation strategies around the world, and we can now begin to compare their relative efficacies.

 

School closures were already part of the US government’s NPI plans for a severe pandemic, and were instituted in the early days of the swine flu outbreak.   But school closures have a cost in terms of social and economic impacts, and must be balanced against the benefits.

 

Although the assumption has been that school closures would reduce transmission of a pandemic virus, the question has always been: How much?

We now have a study, based on school closures in Hong Kong last summer, that give us at least a partial answer to that question.

 

Of course, the old saw that `If you’ve seen one pandemic, you’ve seen one pandemic’ still holds. Methods and rates of transmission can vary from one virus to another, and quite frankly, from one region or society to another. 

 

That said, researchers in Hong Kong have come up with a number they feel illustrates the benefits of early and sustained school closures during this past summer.  

 

Their work appears in this month’s CDC’s Journal of Emerging Infectious Diseases.

 

DOI: 10.3201/eid1603.091216

Wu JT, Cowling BJ, Lau EHY, Ip DKM, Ho L-M, Tsang T, et al. School closure and mitigation of pandemic (H1N1) 2009, Hong Kong. Emerg Infect Dis. 2010 Mar; [Epub ahead of print]

School Closure and Mitigation of Pandemic (H1N1) 2009, Hong Kong

In Hong Kong, kindergartens and primary schools were closed when local transmission of pandemic (H1N1) 2009 was identified. Secondary schools closed for summer vacation shortly afterwards. By fitting a model of reporting and transmission to case data, we estimated that transmission was reduced ≈25% when secondary schools closed

 

A 25% reduction in transmission is actually better than some previous studies had suggested, and as the authors point out below, the benefits of school closures probably extended into the greater community as well.

 

Furthermore, assuming that children are responsible for up to half of all community transmission (8), it is likely that protection of younger children had substantial indirect benefits. Previous studies have suggested that sustained school closures during a pandemic could reduce peak attack rates and prevent 13%–17% of total cases in France (8) or <20% of total cases in the United Kingdom (3).

 

Our finding that the reproductive number declined from 1.5 during the kindergarten and primary school closures to 1.1 during summer vacation suggests that a much more substantial drop in attack rates would result from sustained school closures.

 

 

This study, when combined with others that will no doubt arise from the pandemic, should give public health officials better data to base their school closing decisions on for the next pandemic.

 

It still remains a judgment call, of course.   You still have to balance the severity of the illness against the impact of closing schools.

But at least now we are getting a better idea of what might be gained by such measures.

Study: Effect Of School Closures On Viral Transmission

 

 

# 4087

 

 

You don’t have to be an epidemiologist to know that schools are hotbeds of respiratory illness each winter, and that kids are very efficient spreaders of viruses. 

 

It was for that reason that in early pandemic planning – particularly when considering a high mortality virus such as H5N1 – school closures for up to 12 weeks were prominently featured.

 

Once it was established that the novel H1N1 virus was nowhere near as virulent as bird flu, social policy in most countries was to try to keep schools open as much as possible.

While it has been assumed that closing schools would help curb the spread of a pandemic virus, until now there has been very little research that quantifies the benefit. 

 

Something that we really ought to know before the next pandemic virus emerges.

 

Today we get a study, published in the open access journal BMC Infectious Diseases, that finds that forced school closures can reduce secondary infections by roughly 20%.

 

This study makes the assumption that social mixing and interaction during a pandemic induced school closure would mimic social contacts currently seen during routine weekend and holiday school closures.  

 

Their estimates, therefore, are probably conservative.  Social distancing beyond just the closure of schools would likely be taking place, and large social gatherings probably discouraged. 

 

School closings have costs, both economic and social, and those have to be taken into account as well.  Forced school closings are not something to be done lightly.

 

During a severe pandemic wave, however, this study makes a pretty good case for the closing of schools to significantly lower the attack rate.

 

 

Estimating the impact of school closure on social mixing behaviour and the transmission of close contact infections in eight European countries

 

Niel Hens , Girma Minalu Ayele , Nele Goeyvaerts , Marc Aerts , Joel Mossong , John W Edmunds  and Philippe Beutels

 

BMC Infectious Diseases 2009, 9:187doi:10.1186/1471-2334-9-187

Published:
27 November 2009

Background

Mathematical modelling of infectious disease is increasingly used to help guide public health policy. As directly transmitted infections, such as influenza and tuberculosis, require contact between individuals, knowledge about contact patterns is a necessary pre-requisite of accurate model predictions. Of particular interest is the potential impact of school closure as a means of controlling pandemic influenza (and potentially other pathogens).

Methods

This paper uses a population-based prospective survey of mixing patterns in eight European countries to study the relative change in the basic reproduction number (R0 - the average number of secondary cases from a typical primary case in a fully susceptible population) on weekdays versus weekends and during regular versus holiday periods. The relative change in R0 during holiday periods and weekends gives an indication of the impact collective school closures (and prophylactic absenteeism) may have during a pandemic.

Results

Social contact patterns differ substantially when comparing weekdays to the weekend and regular to holiday periods mainly due to the reduction in work and/or school contacts. For most countries the basic reproduction number decreases from the week to weekends and regular to holiday periods by about 21% and 17%, respectively. However for other countries no significant decrease was observed.

Conclusions

We use a large-scale social contact survey in eight different European countries to gain insights in the relative change in the basic reproduction number on weekdays versus weekends and during regular versus holiday periods. The resulting estimates indicate that school closure can have a substantial impact on the spread of a newly emerging infectious disease that is transmitted via close (non sexual) contacts.

The complete article is available as a provisional PDF. The fully formatted PDF and HTML versions are in production.

Afghanistan Closes Schools Due To H1N1

 

# 3974

 

 

Six days ago Afghanistan declared the pandemic to be an emergency (see Afghanistan Declares H1N1 Emergency), warning that 1 infected person in 80 die from the pandemic virus.  As many as 70,000 deaths.

While those estimates may turn out to be high, there is no doubt that developing nations have graver concerns with this pandemic virus than do countries with access to antivirals, antibiotics, and hospital care.

The challenges facing developing nations in this pandemic are many and very serious (see A Tale of Two Pandemics).   In order to stem the spread of the virus, Afghanistan has now decided to close schools for most of the month of November.

This report from the VOA.

 

Afghanistan Closes Schools Due to Increasing H1N1 Cases

By Sean Maroney

Kabul
08 November 2009

The Afghan government has closed the country's schools and universities for most of November in response to an increased number of H1N1 flu cases. Since July, officials have diagnosed nearly 350 people with the virus. There have been a total of 772 confirmed cases, and 10 people have died.

 

Afghan officials say most of the flu cases have been in Kabul, Parwan and the provinces of Herot, Kandahar, Ningrahar and Bamayan.

 

Afghanistan's Health Minister Dr. Sayed Mohammad Amin Fatemi says only Afghans so far have died from the virus.
He says the basic reason for the deaths has been because the victims went to treatment centers too late. He says most of the foreigners with the virus have been with the NATO forces, and they were able to start their treatments early, which helped their chances for survival.

 

The United Nations World Health Organization representative for Afghanistan, Peter Graass, says that despite the last eight years of medical improvements in the country, there is still a lot more work left to do.

 

"Somewhere between 60 and 70 percent of all Afghans have access within two hours of walking or traveling to basic health services, so that means that under the best of circumstances we have a very sizable - still very sizable - proportion of the population that is basically missing out," he said.

 

He says the Afghan health services are reasonably prepared to deal with the H1N1 outbreak. But he adds that officials believe the actual number of cases is much higher and are preparing for scenarios in which a fourth of the country contracts the flu virus.

 

(Continue . . . )

Japan: Nearly 14,000 Schools Closed Due To Flu

 

# 3901

 

In Japan, concerns over the Shingata Influ  (New strain influenza) run higher than here in the United States.  They are much quicker to don masks, close schools, and to take other steps to slow the spread of the virus.

 

At the start of October, only a little over 3,000 schools were closed in Japan.  That number has quadrupled to nearly 14,000  this week.

 

By contrast, in the United States -  with 2.5 times the population - only about 600 schools have closed this fall.

 

US school closures are rapidly approaching the level seen last spring, when 700 schools were closed during the initial outbreaks of the H1N1 virus.

 

A hat tip to Pathfinder on FluTrackers for this link.

 

 

Nearly 14,000 schools closed due to influenza

Thursday 29th October, 08:36 AM JST

TOKYO —

The health ministry said Wednesday that 13,964 educational facilities, including schools and kindergartens, canceled some or all of their classes due to influenza infections in the week from Oct. 18 to 24, up sharply from 8,534 reported a week earlier. Most of the facilities were hit by the new influenza, according to the Health, Labor and Welfare Ministry.

 

In the week through Sunday, 380 group infections involving more than 10 people have been reported on a preliminary basis, with Hokkaido leading other prefectures with 77 cases, followed by 58 in Tokyo, 36 in Osaka and 33 in Aichi.