Not If, But WhenWith two influenza pandemics in the 19th Century and three in the 20th Century, we’re due for next pandemic Peter A. Reinhardt, Director Department of Environment, Health & Safety
More than any other time in history, mankind faces a crossroads. One path leads to despair and utter hopelessness. The other, to total extinction. Let us pray we have the wisdom to choose correctly. —Woody Allen
3 October 2006 Should We Worry About Avian Flu?
I have been through some terrible things in my life, some of which actually happened. —Mark Twain
3 October 2006 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 Immediate effect Worried Likelihood judgment Exotic/new Severity judgment Catastrophic
3 October 2006 Avian influenza—situation in IndonesiaWHO update 34: 28 September 2006 The Ministry of Health in Indonesia has confirmed the country’s 52nd death from H5N1 avian influenza. The 20-year-old man, whose infection was announced on 27 September, died early in the morning of 28 September. Of the 68 cases confirmed to date in Indonesia, 52 have been fatal.
3 October 2006 H5N1 in Humans First cases (18) reported in Hong Kong in 1997. Six were fatal. Next outbreak occurred in December 2003 Initially cases were limited to Southeast Asia
3 October 2006 A = Public Health Agency of Canada B = American Veterinary Medical Assn. C = CDC
3 October 2006 H5N1 Avian Influenza in Humans
3 October 2006 Influenza Pandemics HHS Pandemic Influenza Plan, October 2005, WHO
3 October 2006 Timeline of Emergence of Influenza A Viruses in Humans Avian Influenza H9 H7 Russian Influenza H5 H5 H1 Asian Influenza H3 Spanish Influenza H2 Hong Kong Influenza H1 1918 1957 1968 1977 1997 2003 1998/9
H5N1 Is Mutating Continuously Evolution of H5N1 Avian Influenza Viruses in Asia: 2003-5. Phylogenetic relationships among N1 neuraminidase (NA) genes of H5N1 influenza viruses.
H5N1 Avian Influenza by Michael Specterpublic health issues staff writer NEW YORKER2006 Most viruses stick to a single species. This one (H5N1) has already affected a more diverse group than any other type of flu, and it has killed many animals previously thought to be resistant: blue pheasants, black swans, turtledoves, clouded leopards, mice, pigs, domestic cats, and tigers. Early in February (2006), nearly five hundred open billed storks were found dead in Thailand's largest freshwater swamp.
Decades-old Variety of Equine (Horse) Influenza has Emerged in DogsSummarized in HHMI BulletinDecember 2005 CDC staff recognized the pathogen as H3N8 equine influenza virus…[which has] occurred for at least 40 years in horses, this virus suddenly made a complete jump into greyhounds. Moreover, this newfound canine influenza…quickly began to spread. Since the winter of 2004 it has been confirmed in outbreaks at racetracks in at least 11 states, affecting thousands of greyhounds... "For scientists worried about interspecies transfer of influenza, this is a rare and striking example," says Ruben O. Donis, a CDC scientist… If the flu can jump from horses to dogs, why not from dogs to people? Donis notes, "…The reality is, we just don't know."
3 October 2006 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)
3 October 2006 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
3 October 2006 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.
3 October 2006 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.
3 October 2006 Impact of a Mild Influenza Pandemic in the United States 75 – 100 million become ill 18 - 45 million outpatient visits 300,000 - 800,000 hospitalizations 88,000 - 300,000 deaths WHO and CDC, Pandemic Influenza Planning Guide for State and Local Officials, 1999
3 October 2006 Characteristics Of An Influenza Pandemic • Simultaneous outbreaks throughout the U.S. limits ability of a jurisdiction to assist others • Many people may be asymptomatic while infectious • Enormous demands on the healthcare system • Potential disruption of national and community infrastructures including transportation, commerce, utilities and public safety due to illness and death among workers and their families • Delays, shortages & unavailability of vaccines & antivirals
“…a pandemic is a local crisis worldwide. It can happen in every state and every city and every town at almost the same time. A pandemic is not like a hurricane or an earthquake, where resources and help can be shifted from one area to another…every community will need to rely on its own planning and its own resources as it fights the outbreak.“ –HHS Secretary Michael O. Leavitt, 13 March 2006
3 October 2006 Chancellor’s Advisory Committee on Pandemic Influenza Preparedness Subcommittees: Closure/Suspension/Academic Continuity Human Resources Fiscal Issues/Business Continuity Communications International Emergency Committee Information Technology Research and Research Animals
3 October 2006 UNC’s Avian Flu/Pandemic Flu Web Site Provide facts; dispel myths Tell people what they can do to prepare and protect themselves Start to discuss international travel—a pandemic’s first impact to UNC Let people know what UNC is doing to prepare and plan for pandemic influenza; reassure and calm
3 October 2006 Start The Mantra of Flu Prevention Get a flu shot Wash your hands Avoid touching your eyes, nose or mouth Cover your mouth with tissue when sneezing Stay away from others if you are sick; don't go to class or work Avoid close contact with people who are sick Get help if you are sick
Emergency Planning Crisis Communi-cations Plan Response Plan Continuity Of Operations Plan Individual and Family Plans
Pandemic Emergency Planning Crisis Communi-cations Plan Response Plan Continuity Of Operations Plans Individual and Family Plans Pandemic Influenza Response Plan Pandemic Influenza COOPs
3 October 2006 Planning Objectives • Minimize the risk of pandemic influenza to students, faculty and staff. • Support students who remain in Chapel Hill. • Continue functions essential to university and hospital operations during a pandemic. • After the pandemic, resume normal teaching, research and service operations as soon as possible.
3 October 2006 Key Factors in Emergency Planning • Risk • Probability • Consequence (severity of pandemic) • Strengths • Business resiliency • External support • Internal response capabilities • Weaknesses • Business vulnerability • External vulnerabilities
3 October 2006 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 case fatality rate, but we cannot predict the severity of the next human pandemic. Will it look like 1918 or 1957?
3 October 2006 U.S. Influenza Burden—Typical Year Deaths 25,000 - 72,000 Hospitalizations 114,000 - 257,500 Physician visits ~ 25 million Infections and illnesses 50 - 60 million Thompson WW et al. JAMA. 2003;289:179-86. Couch RB. Ann Intern Med. 2000;133:992-8. Patriarca PA. JAMA. 1999;282:75-7. ACIP. MMWR. 2004;53(RR06):1-40.
3 October 2006 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 U.S. students from > 600 mi. 7,400 Students in residence halls (2005-6) 1,000 Students & family members in family housing
3 October 2006 Our Cloudy Crystal Ball
3 October 2006 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% case fatality rate (maximum) estimates. See http://www2.cdc.gov/od/fluaid/
3 October 2006 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.
3 October 2006 Our Greatest Risk Therefore, if a severe pandemic were to occur in North Carolina, we should suspend on-campus classes for 7-10 weeks. 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.)
Epi 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
Multiple Community Outbreaks = Wave Community outbreaks (epi curves) are dynamic 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
3 October 2006 Draft UNC-Chapel Hill Criteria for Suspending On-Campus 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.
3 October 2006 Quarantine and Isolation When the influenza pandemic first arrives in Chapel Hill, Public Health authorities will ask daycare facilities and K-12 (or K-6) schools to close. UNC students, faculty and staff will not be subject to quarantine.Instead, public health officials will recommend voluntary social distancing measures. Initial clusters in the world (and U.S.) will be asked to isolate voluntarily; orders will be issued only if they do not. VERY UNLIKELY: “An extremely contagious outbreak could force us to quarantine students.”
3 October 2006 While Classes Are Suspended 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. • 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.
3 October 2006 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% case fatality rate (most likely) estimates for employees. See http://www2.cdc.gov/od/fluaid/
3 October 2006 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 [isolation] 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