9 Pandemic Influenza Reinhardt

What If…?When planning for pandemic influenza, so much depends on what we assume. How can we make those assumptions smarter?: 

What If…? When planning for pandemic influenza, so much depends on what we assume. How can we make those assumptions smarter? Peter A. Reinhardt, Director Dept. of Environment, Health & Safety

Should You Worry About Avian Flu?: 

Should You Worry About Avian Flu?

So Why Are We So Worried About Pandemic Influenza?Because it follows the laws of risk perception!: 

So Why Are We So Worried About Pandemic Influenza? Because it follows the laws of risk perception! High Perceived Risk Not knowable/uncertain Controlled by others Coerced Catastrophic Dreaded Immediate effect Exotic/new

Slide4: 

Timeline of Emergence of Influenza A Viruses in Humans 1918 1957 1968 1977 1997 1998/9 2003 H1 H1 H3 H2 H7 H5 H5 H9 Spanish Influenza Asian Influenza Russian Influenza Avian Influenza Hong Kong Influenza

Influenza Pandemics: 

Influenza Pandemics HHS Pandemic Influenza Plan, October 2005, WHO

H5N1 in Humans: 

H5N1 in Humans Current outbreak began December 2003 Initially cases were limited to Southeast Asia

Global Pandemic Watch: 

Global Pandemic Watch Good news No evidence of sustained human-to-human transmission No reported cases of H5N1 in the U.S. in migratory birds, poultry or humans Bad news H5N1 virus continues to circulate widely in Asia, Europe and Africa Eradication of H5N1 in birds is difficult Other avian influenza viruses detected in poultry in 2004 (H5N2 in Texas and H7N2 in Maryland)

Is it pandemic yet?: 

Is it pandemic yet? Pandemic influenza occurs when a new, novel virus appears, to which population has little or no immunity And the novel virus is able to cause severe illness in humans And the virus is capable of sustained human-to-human transmission

Defining a Pandemic: WHO Phases: 

Defining a Pandemic: WHO Phases Phase 1: No new influenza virus subtypes detected in humans. If animals are infected, risk to humans is low. Phase 2: No new influenza virus subtypes detected in humans. However, a circulating animal influenza virus subtype poses a substantial risk of human disease. Phase 3: Isolated human infections, no human-to-human spread except rare close contacts.

Defining a Pandemic: WHO Phases: 

Defining a Pandemic: WHO Phases Phase 4: Small, highly localized cluster(s), limited human-to-human transmission. Phase 5: Larger localized cluster(s) limited human-to-human spread. Substantial pandemic risk. Phase 6: Pandemic phase: Sustained transmission among humans occurs.

Do we close?Or do we stay open and “weather the storm?”: 

Do we close? Or do we stay open and “weather the storm?” It depends. The severity of an influenza pandemic depends on the transmissibility, morbidity and mortality of the influenza. Influenza caused by the H5N1 strain appears to have a high rate of mortality, but we cannot predict the severity of the next human pandemic. Will it look like 1918 or 1957?

UNC-Chapel Hill Population: 

UNC-Chapel Hill Population 10,264 Full time employees (Fall 2005) 772 Part time employees 27,267 Students (Fall 2005) 1,777 International students 3,000 Students from > 600 miles 7,400 Students in residence halls (2005-6) 1,000 Students & family members in family housing

Our Cloudy Crystal Ball: 

Our Cloudy Crystal Ball

CDC FluAid 2.0 Model Estimates: 

CDC FluAid 2.0 Model Estimates Assuming 35% gross attack rate; student population split 50:50 among 0-18 and 19-64 yrs age groups; using 0.3% mortality rate (maximum) estimates. See http://www2.cdc.gov/od/fluaid/

Our Greatest Risk: 

Our Greatest Risk Our greatest risk is an easily transmissible virus + 7,400 students in residence halls living in close proximity and sharing facilities. Caring for a large number of ill students would strain resources of Housing and Residential Education, Campus Health Service and the UNC Healthcare System, especially if the community is similarly impacted and staff resources are similarly depleted.

Our Greatest Risk: 

Our Greatest Risk We will want to make the class suspension decision early in the period of contagion to allow residential students to return to a less-risky home environment. (We hope to be able to resume the session after the wave has passed.) Therefore, if a severe pandemic were to occur in North Carolina, we should suspend classes for 7-10 weeks.

Pandemic Influenza Epidemic Curve: 

Pandemic Influenza Epidemic Curve Assume that “Epidemics will last 6 to 8 weeks in affected communities.” National Strategy for Pandemic Influenza: Implementation Plan, Homeland Security Council, May 2006 Epi curve

Multiple Community Outbreaks = Wave: 

Multiple Community Outbreaks = Wave Assume that each wave—during which community outbreaks occur across the country—will last 2 to 3 months. National Strategy for Pandemic Influenza: Implementation Plan, Homeland Security Council, May 2006 Community outbreaks (epi curves) are dynamic

Draft UNC-Chapel Hill Criteria for Suspending Classes: 

Draft UNC-Chapel Hill Criteria for Suspending Classes WHO Phase 6—Pandemic period: Increased and sustained transmission in the general U.S. population. Confirmation of a high rate of transmissibility, morbidity and/or mortality. Local public health recommendations to curtail/cancel public activities in North Carolina. Immediately preceded by falling class attendance, students leaving campus. Rising employee absenteeism.

While Classes Are Suspended: 

While Classes Are Suspended 700 students (e.g., international students) will remain in residence halls scattered in various locations (no longer living in close proximity). They will need support. 1,000 people in family housing will be in close quarters and at relatively high risk. 4,000 students will remain in off-campus housing, including fraternities and sororities. 5,700 students and student families will likely remain in Chapel Hill because of international travel restrictions, other travel difficulties, or because they do not have a suitable alternative living option.

While Classes Are Suspended: 

While Classes Are Suspended Assuming 35% gross attack rate; student and family population split 50:50 among 0-18 and 19-64 yrs age groups; using 0.2% mortality rate (most likely) estimates for employees. See http://www2.cdc.gov/od/fluaid/

Issues While Classes Are Suspended: 

Issues While Classes Are Suspended Housing and Residential Education, and Campus Health Service need to care for remaining ill students and their families. What activities can continue? What activities should we postpone? What essential functions will need to continue even when classes are suspended?

Will Distance Learning Help?Not much: total distance learning credit hours at UNC: : 

Will Distance Learning Help? Not much: total distance learning credit hours at UNC: Some instruction might continue using a less formal form of distance learning.

Employee Absenteeism: 

Employee Absenteeism “[Assume] that up to 40 percent of [staff] may be absent for periods of about 2 weeks at the height of a pandemic wave, with lower levels of staff absent for a few weeks on either side of the peak. Absenteeism will increase not only because of personal illness…but also because employees may be caring for ill family members, under voluntary home quarantine due to an ill household member, minding children dismissed from school, following public health guidance, or simply staying at home out of safety concerns.” National Strategy for Pandemic Influenza: Implementation Plan, Homeland Security Council, May 2006

Isolation and Quarantine: 

Isolation and Quarantine When the influenza pandemic first arrives in Chapel Hill, Public Health authorities will immediately ask daycare facilities and K-12 schools to close. Students, faculty and staff will not be subject to quarantine. Instead, public health officials will rely on voluntary social distancing measures. Initial clusters will be subject to voluntary isolation; quarantine orders will be issued only if that doesn’t work. VERY UNLIKELY: “An extremely contagious outbreak could force us to quarantine students.”

Quenching PlanPublic health officials are actively planning to slow (or quench) the spread of pandemic influenza: 

Quenching Plan Public health officials are actively planning to slow (or quench) the spread of pandemic influenza Public health officials are closely surveilling suspected cases via doctors’ offices, clinics, hospitals and local public health departments. Public health officials will attempt to isolate the first clusters to prevent the first cases from exposing others.

Quenching Plan: 

Quenching Plan As soon as the first cases appear locally, health officials will close daycare facilities and K-12 schools for those locales. Public health officials will recommend that the local population take other social distancing and self-shielding measures. Antiviral drugs—although in short supply—will quickly be distributed to those exposed to the first cases, as well as local susceptible populations

Quenching Plan: 

Quenching Plan A vaccine based on H5N1—although of limited effectiveness and in very short supply—will be rushed into use for people near the first clusters, and for local susceptible populations

Alternate Answers: 

Alternate Answers

Quenching and Its Affects: 

Quenching and Its Affects

Epidemic Curves With Quenching: 

Epidemic Curves With Quenching

After the Wave Has Passed: 

After the Wave Has Passed After the wave has passed, recovery will be slow and difficult. Grieving and adjustment for those who have lost loved ones, friends and coworkers. Those who became ill and survived may take months to fully recover. Exhausted caregivers will need rest, time off to get their affairs in order, and mental health support.

After the Wave Has Passed: 

After the Wave Has Passed Business will be slow to recover, slow to replenish inventories, and slow to replace labor. Economic loss will cause business to contract, cut costs, and layoff workers. Worry and fear of the next wave.

Stepwise Preparations: 

Stepwise Preparations

Key Factors in Planning: 

Key Factors in Planning Risk Probability Consequence (severity of pandemic) Strengths Business resiliency External support Internal response capabilities Weaknesses Business vulnerability External vulnerabilities

If We’re Too Pessimistic: 

If We’re Too Pessimistic Waste resources that could have been allocated to other risks Economic impact: air travel, poultry sales; life insurance For most people, planning for the extreme worst case is boundless, too abstract, too complex, too time-consuming and too frightening. More people participate and cooperate if we are reasonable. “The only thing we have to fear is fear itself—nameless, unreasoning, unjustified terror which paralyzes needed efforts to convert retreat into advance.” —Franklin Delano Roosevelt

Recommendations: 

Recommendations The next flu pandemic may not happen in our lifetimes, but some other type of disaster most assuredly will. Take this as an opportunity to improve: All-hazard emergency plans and preparedness The structure and processes for emergency command, management & decisionmaking Continuity of Operation (COOP)/Business Continuity Plans On-campus mass dispensing/vaccination procedures Tornado in Miami, 12 May 1997

Questions?: 

Questions? Peter A. Reinhardt, Director Department of Environment, Health & Safety University of North Carolina 1120 Estes Drive Extension., CB# 1650 Chapel Hill, NC 27599-1650 http://ehs.unc.edu pareinhardt@ehs.unc.edu 919-843-5913