Pandemic Influenza Preparedness & Response Occupational Safety and Health Course for Healthcare Professionals
Part 1: Impact of Pandemic Influenza • Part 2: Key Elements of a Preparedness Plan • Part 3: Strategies to Support Continuity of Operations • Part 4: Resources to Support Pandemic Influenza Preparedness Planning
What is our history with pandemics? • What are the potential hazards and risks associated with an influenza pandemic? • The current pandemic situation (2009 H1N1). • Differences between seasonal, avian, and pandemic influenza. • What are the signs and symptoms of seasonal, avian, and pandemic influenza? • What is the potential impact on your healthcare organization when a pandemic occurs?
The Reality “Those who cannot remember the past are condemned to repeat it.” G. Santayana
Pandemic Influenza • Is pandemic flu something we should be concerned about? • Most infectious disease experts have been predicting another influenza pandemic for years. • In June 2009 the WHO declared that the world was in the midst of a pandemic caused by the H1N1 virus. • The first wave of this pandemic occurred in the Spring, the second started in late summer/early Fall; there may be more waves. • Preparing for a pandemic is similar to having a fire prevention plan and a fire protection plan for your business, even though you do not plan to ever have a fire..
“ No one can be sure of the total losses ______ suffered, but when it comes to pandemics, there is no rational basis to believe that the early years of the 21st century will be different than the past. If a pandemic strikes, it will come to _________.” ( Secretary of Health and Human Services report/speech in just about every state in the US in 2006)
Pandemic Influenza • What is our history with influenza pandemics? The 1918-1919 Flu Pandemic • Over 50 million died in the world due to this pandemic. • Killed more people across the globe in the two significant waves,1918-1919, than AIDS has in 24 years. • Killed more people in one year than the bubonic plague (Black Death) did in 100 years in Middle Ages. ( The Great Influenza, John M. Barry)
http://www.youtube.com/watch?v=8NRTC1BlHg0 (Go to flu.gov)
Pandemic Influenza • When flu is not just the flu – the different viral strains: • 1918-1919 H1N1 (not the same as 2009 virus) • 1957-1958 H2N2 • 1968-1969 H3N2 • 2009 H1N1
Pandemic Influenza IMPACT • Years Deaths Affected • 1918-1919 500,000 young healthy adults • 1957-1958 70,000 infants & elderly • 1968-1969 34,000 infants & elderly • H1N1 (2009) children, young adults Seasonal 36,000 infants & elderly
What happened? • Where did this start? • 2009 H1N1: unique combination of swine, bird, and human influenza virus. • First cases reported in Mexico in April. • First case reported in US April 15th. • Spread to 33 countries by May, to over 213 countries by January 2010.
Number of cases across the globe: over 700,000 cases; over 16,713 deaths. (WHO 2/28/10) • Number of hospitalized cases in US: over 40,000 • Deaths reported in US: over 2500 • Pediatric deaths: 329 (4/26/09-2/27/10) • CDC Estimates? • Basic symptoms similar to seasonal influenza. • Mild, short duration, acute upper respiratory illness. • Recovery aided by current anti-viral medications.
Have experienced two waves - could have more waves. • The virus can mutate to a more virulent strain, a strain causing more severe illness. • Development and testing of the new vaccine has occurred, vaccine now being distributed and administered. As of November 30th ,“vaccine widely available”. • Up to this point, this is a mild influenza, easily spread human to human, with relatively short duration. • Case-fatality ratio of 0.4%. • Continued monitoring by state & local health departments, WHO and CDC, with frequent updates.
The Reality • WHO response: raised the Pandemic Alert level to 6. • CDC quickly distributed the special testing kits to all state health departments and other countries to support faster and more accurate testing of specimens. • Initially, large numbers of “worried well”. • Initial Focus : prevention of spread through careful hygiene practices, voluntary isolation of ill at their homes, use of appropriate PPE by health care workers, distribution of antiviral medications from the SNS. • Recognition that adults are infectious 1 day prior to symptoms – 5 days; children for up to 10 days.
What was the response of your community? • What was the response of your organization? • Reaction/impact on your employees? • If all businesses had a well-established Pandemic Preparedness Plan, how would we have reacted?
Absenteeism – up to 40-60% of employees affected • Sick employees • Caring for sick family members • Child care- schools closed/daycare closed • Afraid to come to work • Changes in Patterns of Services • Increased demand for some services • Decreased demand for other services • Home delivery, drive-through windows, expanded hours for convenience. • • Interrupted Supply/Delivery Chain
Major impact on all businesses and social processes, including our families. • Local efforts/strategies will be critically needed. • Federal and state agencies will be unable to meet all local needs.
Characteristic Moderate (1958/68-like) Severe (1918-like) Illness 90 million (30%) 90 million (30%) Outpatient medical care 45 million (50%) 45 million (50%) Hospitalization 865,000 (1%) 9,900,000 (11%) ICU care 128,750 1,485,000 Mechanical ventilation 64,875 745,500 Deaths 209,000(.23%) 1,903,000(2.1%) Estimates based on US population of 300,000,000; infection rate of 30%)
Definitions • Seasonal influenza: the “flu”- periodic outbreaks of acute onset viral respiratory infection, caused by circulating strains of human influenza A and B viruses. * in temperate regions the flu occurs in the winter months (Dec-April). * between 5-20% of the US population may be infected annually. * Each year, on average, 36,000 people die from the flu and associated complications. * most people have some immunity to the virus. * each year, the Flu Vaccine is prepared in advance to protect against viral strains that are expected to circulate that season.
Definitions • Avian influenza: “bird flu” – caused by type A viruses; infect water and shore birds and can spread to domestic poultry. • There are two groups of these viruses: * low pathogenic: naturally occurs in wild birds and can spread to domestic birds – pose little threat to humans. * highly pathogenic: spreads rapidly, high death rate in poultry; H5N1 strain is rapidly spreading in birds in some locations. H5N1: has crossed the species barrier to infect humans, is the most deadly of the viruses that has done this. Most of these cases have involved contact with infected poultry. * Avian influenza has not reached the level of a pandemic.
Definitions • Pandemic influenza: global disease outbreak. A flu pandemic occurs when a new virus or a mutated version of a current virus, emerges for which we have little or no immunity and for which we have no vaccine. So far, only “A” viruses have caused pandemics. * serious illness outcomes. * illness spreads easily and quickly person to person. * will sweep across a country and around the globe in a short time. * may occur in 2-3 waves, each lasting 8-12 weeks, spanning 12-18 months.
Seasonal Influenza: * abrupt onset * fever, chills, fatigue, muscle aches, headache, dry cough, upper respiratory congestion, sore throat * time from exposure to onset: 1-4 days * adults are infectious from 1-5 days after onset * children are infectious much longer: + 10 days * usual recovery time: 3-7 days * cough and weakness/aches: up to 2-3 weeks
Highly Pathogenic Avian Influenza (HPAI H5N1) in Humans * primarily in children and young adults * high fever and cough * lower respiratory tract symptoms * shortness of breath * development of viral pneumonia * diarrhea, abdominal pain, and vomiting frequently reported. * in many cases, death follows quickly after signs & symptoms noticed.
Prior Influenza Pandemics: * 1918, caused by H1N1 viruses – more severe signs and symptoms * predominantly affected young, healthy adults, ages 15-35. * occurred suddenly and with great severity. * death in just a few days. * in many of the cases, those that survived the initial illness, often died later of a secondary bacterial pneumonia.
Similar to seasonal flu • Fever • Cough or sore throat • Runny or stuffy nose • Body aches • Headaches • Chills • Fatigue • Diarrhea and vomiting in some individuals Concerns: Subsequent waves could be worse due to mutation of the virus.
If we understand the common, expected modes of transmission of an influenza virus, we can implement strategies with all employees and patients/ families to minimize exposure, prevent and control spread.
“…the proportional contribution and clinical importance of the possible modes of transmission of influenza (i.e., droplet, airborne, and contact) remains unclear and may depend on the strain of virus ultimately responsible for a pandemic.” HHS. Interim Guidance on Planning for the Use of Surgical Masks And Respirators in Health Care Settings during an Influenza Pandemic. October 2006.
Contact of the mucous membranes of the nose, mouth or eyes of a susceptible person with large particle droplets containing microorganisms expelled by an infected person during coughing, sneezing, or even breathing. • Major route of transmission of flu. • Droplets of > 50 - 100 µm. • Settle from air within 3 – 6 feet.
Occurs through direct contact with contaminated hands, skin, or fomites* followed by self-inoculation of mucosa. *Fomite - an inanimate object that is able to harbor pathogenic organisms and therefore may serve as a agent of transmission (phones, computer keyboards, etc.)
Concern exists about the possibility of short-range aerosol transmission as a possible route of spread, although research evidence is very limited. • Localized airborne transmission might occur over short distances (i.e., three to six feet) via droplet nuclei or particles that are small enough to be inhaled. • Relative contribution of short-range airborne transmission to influenza outbreaks is unknown.
Transmission to humans Avian virus Avian virus Reassortment in humans Avian virus Human virus Reassortment in swine
HPAI H5N1 and other avian viruses – of greatest concern. • Transmission modes may include contact, airborne, and blood, CSF, and fecal contact transmission, as well as to mucous membranes of the eye. • Mutated or reassorted viruses may behave differently. .
What would need to happen: • Susceptible population. • Transmission from birds/poultry to human. • Mutation of the virus. • Easy transmission human to human. • Sustained human to human transmission.
Treatment Options • Seasonal Influenza: * Influenza A (for treatment and prophylaxis) may include: a. amantadine and rimantadine (not recommended due to resistance) b. zanamivir and oseltamivir * Prescription drugs – should be started within 2 days of symptom onset.
Treatment Options • Pandemic Influenza: * Use of antiviral drugs has been shown to reduce mortality and morbidity. * Can shorten duration and severity. * Because of availability, such drugs are suggested for high-risk, priority groups.
With high risk groups: seeking medical attention early is critical. • Staying home if ill is very important. • Serious post-influenza infections can occur and require aggressive treatment. • High risk groups: pregnant women, caregivers of young children, healthcare workers and emergency responders, young people (6 mo. to 24 yrs), medically compromised adults(25-64 yrs.).
Much has been done to prepare for a pandemic. • There are some guidelines that are in use at the international and our national level. • Need to be aware of these “risk classification structures”.
Who’s Who: World Health Organization(Phases1-6) US Government (Stages 1-6) Centers for Disease Controland Prevention — CDC (Pandemic Severity Index, 1-5) OSHA Occupational Exposure Risk Pyramid
Working with all countries to secure latest information, share information, support medical testing and care, and develop preventive and intervention strategies. • Many, many challenges across the globe in terms of information sharing.
WHO Phases of Pandemic Alert • INTERPANDEMIC PERIOD • Phase 1: no viruses circulating among animals have been reported to cause infections in humans. • Phase 2: an animal influenza virus circulating among domesticated or wild animals is known to have caused infection in humans, and is therefore considered a potential pandemic threat.
WHO Phases of Pandemic Alert • PANDEMIC ALERT PERIOD • Phase 3: an animal or human-animal influenza reassortant virus has caused sporadic cases or small clusters of disease in people, but has not resulted in human-to-human transmission sufficient to sustain community-level outbreaks. Limited human-to-human transmission may occur under some circumstances, for example, when there is close contact between an infected person and an unprotected caregiver. However, limited transmission under such restricted circumstances does not indicate that the virus has gained the level of transmissibility among humans necessary to cause a pandemic.
WHO Phases of Pandemic Alert • PANDEMIC ALERT PERIOD • Phase 4: characterized by verified human-to-human transmission of an animal or human-animal influenza reassortant virus able to cause “community-level outbreaks.” The ability to cause sustained disease outbreaks in a community marks a significant upwards shift in the risk for a pandemic. Any country that suspects or has verified such an event should urgently consult with WHO so that the situation can be jointly assessed and a decision made by the affected country if implementation of a rapid pandemic containment operation is warranted. Phase 4 indicates a significant increase in risk of a pandemic but does not necessarily mean that a pandemic is a forgone conclusion. 45
WHO Phases of Pandemic Alert • PANDEMIC ALERT PERIOD • Phase 5: characterized by human-to-human spread of the virus into at least two countries in one WHO region. While most countries will not be affected at this stage, the declaration of Phase 5 is a strong signal that a pandemic is imminent and that the time to finalize the organization, communication, and implementation of the planned mitigation measures is short. 46
WHO Phases of Pandemic Alert PANDEMIC PERIODS • Phase 6:characterized by community level outbreaks in at least one other country in a different WHO region in addition to the criteria defined in Phase 5. Designation of this phase will indicate that a global pandemic is under way. • POST-PEAK PERIOD: pandemic disease levels in most countries with adequate surveillance will have dropped below peak observed levels. The post-peak period signifies that pandemic activity appears to be decreasing; however, it is uncertain if additional waves will occur and countries will need to be prepared for a second wave.
Very High Exposure Risk: • Performing aerosol-generating procedures on known/suspected pandemic patients. • HCW/lab staff collecting or handling specimens from known or suspected pandemic patients. • High Exposure Risk: • HCW and support staff exposed to known or suspected pandemic patients. • Medical transport of known or suspected pandemic patients in enclosed vehicles. • Performing autopsies on known or suspected pandemic patient(s). • Medium Exposure Risk: • Employees with high-frequency close contact with the general population (e.g., schools, high-volume retail). • Lower Exposure Risk (Caution): • Employees who have minimal close contact with the general public and other coworkers (e.g., office workers).