510 likes | 630 Views
Pandemic Influenza. The Business Perspective Golub July 2006. Influenza A. Single stranded RNA Subtyped based on surface glycoproteins • 16 hemagglutinins (HA) • 9 neuraminidases (NA) 8 gene segments. Seasonal Flu.
E N D
Pandemic Influenza The Business Perspective Golub July 2006
Influenza A • Single stranded RNA • Subtyped based on surface • glycoproteins • • 16 hemagglutinins (HA) • • 9 neuraminidases (NA) • 8 gene segments
Seasonal Flu • Adults can infect others 1 day before symptoms & up to 7 days after (ave 5)-children infectious >10 days and young children shed virus 6 d pre onset • Incubation period 1- 4 days, ave 2 days. • Spread by coughing and sneezing (droplets, some airborne) and contact, watch debate on PPE (airborne vs droplet ) • Up to 50 % cases spread by asymptomatic individuals • Survives 12 -24 hr hard surface; 12 hr porous, longer if cold & dry, 5 minutes on hands • Reproductive Number (Ro): ave. number others infected by by 1 infected individual; influenza 2-10 • Spread a function of asymptomatic shedding, speed of transmission (serial interval) and Ro transmission
Asian H5N1 • Mostly a GI disease in birds -birds excrete virus at least 10 days in stool & secretions days in stool & secretions • Virus survives well in feces and water -35d in feces 4 C 6d 37 C, wks poultry house environ.; litter/feces 37 C, wks poultry house environ.; litter/feces • Has adapted wild birds to poultry and now back to wild birds from poultry • Broadening adaptation to mammals and high lethality –tigers, leopards, cats, ferrets, mice, pigs, humans • Incubation period up to 8 days in humans • Mainly back yard poultry, fighting cocks (Thailand) ; hard to get; watch lower PPE requirements HCWs , precaution levels • Significant likelihood of arrival in N America of current nonsustainable transmission H5N1 within 1 -2 yrs • Significant likelihood non Asian H5N1 (LPAI) will be identified in N America as screening efforts grow Have an avian influenza plan separate from pandemic plan
Antigenic Drift vs Shift • • Drift • Point mutations in viral RNA: copying error • • Continual process • • Causes yearly epidemics • • Requires annual update of vaccine • • Shift • • Replacement of H, or H&N (i.e. new subtype) • • Sporadic event • • Can result in a pandemic (not a given)
When is it a pandemic? • An influenza pandemic is a global outbreak of disease that occurs when: • • A new influenza A virus appears or “emerges” in the human population, and • • It causes serious illness in humans, and • • It spreads easily from person to person worldwide
What we know about Pandemics • Rare (1918-19, 1957, 1968) • • “SHIFT happens” • • Transmission is highly efficient among humans, • incubation is short • • EVERYONE is susceptible • • Virulence is variable • • Resistance to antiviral agents is variable • • Shedding precedes symptoms by ½ day
Importance of Good Match • We need to know what strains are most likely to occur each season (Mortality: 36,000 per year) • • We absolutely must know what strain is the cause of a new pandemic (Mortality: order of magnitude higher) • • Importance of international viral surveillance
Current Status • No Asian H5N1 strain in North America now • Human cases require close contact with ill/dead poultry/droppings/carcasses and is hard to get • No sustained human to human transmission • We have some time to plan • Planning efforts are ramping up • Intense watching to detect early transmission clusters and viral change
July 2006 • The number of new countries reporting human cases increased from 4 to 9 after October 2005, following the geographical extension of outbreaks among avian populations. • Half of the cases occurred in people under the age of 20 years; 90% of cases occurred in people under the age of 40 years. • The overall case-fatality rate was 56%. Case fatality was high in all age groups but was highest in persons aged 10 to 39 years. • The case-fatality profile by age group differs from that seen in seasonal influenza, where mortality is highest in the elderly. • The overall case-fatality rate was highest in 2004 (73%), followed by 63% to date in 2006, and 43% in 2005. • Assessment of mortality rates and the time intervals between symptom onset and hospitalization and between symptom onset and death suggests that the illness pattern has not changed substantially during the three years. • Cases have occurred all year round. However, the incidence of human cases peaked, in each of the three years in which cases have occurred, during the period roughly corresponding to winter and spring in the northern hemisphere. If this pattern continues, an upsurge in cases could be anticipated starting in late 2006 or early 2007.
However… • H5N1 established in birds, spreading, not going away, becoming more lethal and broadening adaptation in mammals and birds • 50%+ human case fatality rate • Vaccine and antivirals will not help in early pandemic • Manu transmission unknowns when becomes transmissible • Very short time to identify and ring clusters
Challenges • Pandemic of some sort will return eventually • Preparations are and immense undertaking • Uncertain and incomplete information • Balance: • Too much-too early-sky is falling attitude, risk liberty and economy, pandemic fatigue • Too little-to late- miss chances to contain, mistrust, unrest, lives • Truth communicated quickly, even if incomplete is most effective
Planning Parameters • Ro = approx. 2 • Targets children and young adults • 25-35 % world infected • CFR 1-20% • 15 % absent 8 weeks above background and absence rates up to 50% at peak • 2-3 waves 4-8 weeks each 12-24-36 months to move through • Intense efforts to keep out early and to ring clusters • If these don’t work, social distancing and measures to reduce illness center stage
Early Measures • Travel restrictions, screening, quarantines Intense information need • Public health measures • • intense surveillance: cases, source, contacts • • isolation & quarantine of individuals • Antivirals have a role here-treatment and prophylaxis prophylaxis • Demand for masks, alcohol gel, antivirals • Policy issues -telecommuting, ill at work, stay home if ill, travel
Planning Stages • ID critical products, services, functions, suppliers, contractors, employees • Reduced workforce operations • ID ways to increase social distancing • Purchase contingency supplies masks, tissues, alcohol gel, surface sanitizers • Employee training on hand washing/gel, resp. etiquette, stay at home if ill . • Establish triggers to activate plan stages • Succession plans • Exercises and refinement of plans
Prep work • Influenza team-members (health and safety executives, HR, Marcom, OPS, business continuity planning, Security), • Leadership, rotation, succession • Communications: processes and parties-employees, suppliers, customers, • Solid two way UTD info and liaisons with medical & govt. public health resources • Modify ICS -rolling shifts 4 rolling shifts 4-8-12 wks • Policies -travel, telecommuting, LOA, ill at work, ees quarantined
Cluster control • Communications • Intensify employee training on hand washing, Resp etiquette, stay home if ill • Ready for intense public health investigations and orders, movement & travel restrictions as attempt to ring • Deal with medication prioritization/availability issues • Dealing with isolation of ill and quarantine of well exposed, employees , employees-worried, ill, RTW, LOA Effects on plants, products, services, suppliers, vendors, customers-demand up/down • Ready for crowd restrictions -school closures and other gatherings including work potential closure
Later pandemic scenario • If cluster control fails • Health care system overwhelmed-not enough regular beds, ICU beds, ICU Beds, antivirals • Alternative care sites-schools, home, isolation/care, hotels, tents, gyms • Essential services may break down - delivery, transportation, utilities • Just in time inventories impacted – food, raw materials, deliveries • Contractors and subcontractors
Social distancing measures, snow days, work at home, cancellation of gatherings • School closures add to worker absences • Absences, supply chain and infrastructure issues cause shift to only essential services and products • Plant closure issues • Support for those at home, ill • Mental health issues
Pandemic Management • Influenza & ICS team rotation • Communications • Reduced workforce, essential products & services, scale back -demand may be up or down • Managing ill employees, medical evacuations • Cluster ringing less useful; medication shortages • Social distance measures • Work area cleaning • Adequate supplies of tissues, masks, cleansers • Closures • Support for those at home, ill, recovering, helping Support for those at home • Mental health • Monitoring ees; preparing/encouraging return of those recovered
Recovery • Survivors in demand at work • Mental health issues • Decedent affairs issues continue • Preparation for additional waves • Staging re-openings capability/demand • Variable recovery of different sectors, suppliers, contractors • Many unknowns
Pandemic Recovery • Communications • Scaling up services and products • production down but demand may down or up • Reopening facilities, or not Reopening facilities, • Recovering workers and families • Mental health • Possibility of returning waves • Succession plans • Manage return to new status