400 likes | 662 Views
Community Mitigation of Pandemic Influenza. What Key Stakeholders Need to Know Poudre School District Board of Education November 13, 2007. What is a flu pandemic?.
E N D
Community Mitigation of Pandemic Influenza What Key Stakeholders Need to Know Poudre School District Board of Education November 13, 2007
What is a flu pandemic? • Influenza pandemics occur when an animal flu virus—usually a bird flu virus—that has never infected people alive today changes in ways that it can • Infect humans • Spreads easily between them, causing illness throughout the world.
What is a flu pandemic? • Pandemics are natural events that happen about 3 times per century (in 1918, 1957, and 1968) • They can be mild (not much worse than a bad seasonal flu outbreak) or severe (killing millions all over the world)
Infectious Disease Deaths in the 20th century Deaths per 100,000 per year United States, 1900-1996 1957 1968 1918 JAMA.1999; 281: 61-66.
Currently we can’t stop a pandemic • We can’t stop a pandemic, but we can lessen the harm through control measures Without control measures Impact With control measures Weeks
What actions should we take in a pandemic? • Mandatory or voluntary? • Which combinations of actions? • At what point in the outbreak? • What evidence is there that these actions will work?
Potential Tools in Our Toolbox • Our best countermeasure – vaccine – will probably be unavailable during the first wave of a pandemic • Antiviral treatment may not be available in sufficient quantities. • The effectiveness of antiviral treatment is not clear.
Recent CDC guidance • Community strategies recommended for pandemic flu when vaccines and antivirals are not available http://www.pandemicflu.gov/plan/community/community_mitigation.pdf
4 Key Community tools • Asking those who are ill to remain at home • Asking household members of ill persons to remain at home • Child “social distancing” – closure of schools and places children gather • Workplace/community Adult “social distancing
Control measures will be based on pandemic severity • Severity measured by case-fatality rate (# that die / # that become ill) as determined in region where a pandemic begins (likely not CO, nor even USA) • Pandemic Severity Index created to help communicate level of danger to the public, similar to the well-known hurricane index.
For comparison, the case-fatality rate of the 1918 pandemic was 2.5% in the U.S. the case-fatality rate of H5N1 in 2006 was 69%
Mild Moderate Severe Category 1 Category 2-3 Category 4-5 Case Fatality Rate < 0.1% 0.1 - <1% 1%-2% or higher Voluntary Isolation Recommended Recommended Recommended Voluntary Quarantine Not recommended Consider Recommended Dismissing classes Not recommended Consider Recommended Community social distancing Not recommended Consider Recommended Workplace protections Encourage good hygiene Social distancing Aggressive social distancing Severity Index will drive actions
Two approaches to look at effectivenessof control measures • Looking back at data from 1918 to look for evidence that certain interventions worked • Modeling influenza outbreak using mathematical tools
Weekly mortality data provided by Marc Lipsitch (personal communication)
Timing is everything • Not just whatwas done but when it was done made a big difference • Trigger to implement school closure in current guidance is when first cases occur anywhere in state • Could be very controversial decision
#1 Pandemic outbreak: No intervention #2 Daily Cases Pandemic outbreak: With intervention #3 Days since First Case Purpose of Community-Based Interventions 1. Delay outbreak peak 2. Decrease peak burden on hospitals/ infrastructure 3. Diminish overall cases and health impacts Health care capacity
What models tell usabout actions to reducepandemic flu spread
Why does closing schools (dismissing students) make such a difference?
Evidence to Support Dismissing Students • Children are more susceptible to flu and more contagious than adults • Children are believed to be the main introducers of influenza into households. • School closure during influenza epidemics has resulted in significant decreases in the diagnoses of respiratory infections, visits to physicians, and emergency departments. • Reducing infection in children (via vaccines) has reduced flu rates in all ages in community
Workplace / Classroom Social Density Offices Hospitals 7.8 feet Elementary Schools 16.2 feet 11.7 feet 3.9 feet http://buildingsdatabook.eren.doe.gov/docs/7.4.4.xls Residences
What can be done to reduce adverse impacts of dismissing students?
Adverse impacts • Difficulties of working parents with no child care provider for younger students; impact on other workplaces. • Loss of children’s learning • Loss of school meal programs for low-income children • Loss of state funding for school districts
Labor Status of Households (U.S.) 66 million – No children 18 million >= age12 5 million 9 million Non-working adult 8 million Source: U.S. Census Bureau, Population Division, Current Population Survey, 2003 Annual Social and Economic Supplement http://www.census.gov/population/www/socdemo/hh-fam/cps2003.html
Possible solutions for working parents • Family or friends to provide care • Volunteers to provide care to small numbers of children (no more than 6) • Teleworking option for parents • Shift changes allowing parents to be home at different times
Possible solutions for child instruction • Use email, web lessons, mailed assignments, cable TV, phone calls to continue learning • Provide parents with home- schooling materials appropriate for their child
Possible solutions of loss of school meals • Weekly parent pick-up or home delivery of food items for child • Other community food providers
Possible solutions for state funding of schools • Governor has the power to waive state statutes and regulations in emergency • School districts should work now with legislators and governor to ensure funding of school operations if severe pandemic sends children home
Community Mitigation Summary • Ill persons should be isolated • Voluntary home quarantine for household contacts • Social distancing measures • Dismissing students may have profound impact • Workplace social distancing and liberal leave NOT closure (for most) • Cancellation of public events, closure of entertainment venues (movies, sports,etc.), even church services may be cancelled
Key Stakeholders must • Understand reasons for public health recommendations • Participate in discussions about such interventions with a goal of reaching consensus • Work together to do what need to be done to save lives.
Charlie, 45 Jessie, 40 Florence, 19 Tommy, 16 Harry, 10 Bobbie, 8 Davie, 6 Willie, 4 A Larimer County family -- all 8 died in a 10-day period, Oct – Nov. 1918