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InfluenzaInfluenza
Brian Svazas, MD, MPH, FACOEMMedical Director
Fermi National Accelerator Laboratory
Flu Theories Of OriginFlu Theories Of Origin
• China was the point of origin for the pandemics of 1889, 1957, and 1968.
• three major pandemics of the last 100 years began there
• Appears To Occur Where Pigs and/Or Fowl Cohabitate With Man
• Jump Across Species• Modified Via Person To Person
Spread
Three FlavorsThree Flavors
• Type A– Moderate to Severe Disease– All Age Groups– Humans and All Other
Animals
• Type B– Mild– Humans Only– Children Primarily
• Type C– Rare in Humans– No Epidemics
Influenza A: Influenza A: A Shifty CharacterA Shifty Character
The H an N Antigens can Shift or Drift• Shift results in a radically new antigen site
that almost no one living has seen before– Occurs every 10-40 years– Usually occurs with genetic swap with animal
based virus
• Drift is when the antigens alter slightly enough to warrant reclassification– About every 2-3 years one sees “second
wave”
Influenza Loves KidsInfluenza Loves Kids
• Children typically have far greater viral loads than adults
• Children typically have the poorest hygiene
1. Hall & Douglas, Pediatarics 1975;55:673
2. Evans & Kline PIDJ, 1995;14: 332 3. Klimov et al. JID 1995;172:1352
Kids and FluKids and FluViral SheddingViral Shedding
• Normal infants: up to 14 days• Nosocomial infection in infants : up to 21 days1
• HIV-infected child: up to 63 days2
• SCID patient: 5 months3
– Rapid development of antiviral resistance to rimantadine noted in both HIV-infected child and SCID patient; note that rimantadine-resistant virus can be spread to other patients
1. Hall & Douglas, Pediatarics 1975;55:673
2. Evans & Kline PIDJ, 1995;14: 332 3. Klimov et al. JID 1995;172:1352
SpreadSpread
• Droplets in a sneeze travel as fast as 150 ft/sec and as far as 12 feet
Discover Science Almanac August 2004, page 381
Virus’ VisitVirus’ Visit
• Infects Nasal Mucosa• Multiplies There For 48 Hr• At The 48 Hr Mark We Know
Something Is Wrong• Peak Replication at 72 Hr As Virus
Heads Deeper In Respiratory Tract
Signs: When to Suspect the Signs: When to Suspect the FluFlu
• Chills, fever, headache, and muscular pain mark the onset of influenza.
• Common Complaints of headache, pains in back, arms, legs and bones, sore throat, tightness in chest and cough.
• Constipation common, Other GI Complaints Not As Likely
• The initial temperature ranged from 99 degrees to 106 degrees, the average being about 102 degrees.
• The bar will likely be lower for screening: Airports and other venues in case of Pandemic. (100F 38C)
TreatmentTreatment• Rest• Stay ahead on fluids
– Fever– Rhinitis
• Avoid Tobacco & Alcohol• Medication to relieve symptoms
– Be Aware of Aspirin and Children
• Antivirals Tamiflu and Relenza– Decrease Severity– Decrease Duration– Reduce Viral Shedding (Your less contagious and for
less days)
Seasonal InfluenzaSeasonal InfluenzaVaccine SupplyVaccine Supply
• 2002-2003 Season Oversupply with 95 Million Doses Produced
• 2003-2004 Season Shortage with 87 Million Doses Produced
• 2004-2005 61 Million Doses (Chiron Shortage)
• 2005-2006 70 Million Doses est. (Chiron Retooled)
• 2006-2007 120 Million Doses
I’m <65I’m <65 + Healthy + Healthy
What’s in it for me?What’s in it for me?• 34-44% Reduction in
Physician Visits• 32-45% Reduction in Lost
Workdays (Includes your weekends!!!)
• 25% Reduction in Antibiotic Use (Co-Infections)
• Less chance of getting mislabeled as a SARS case or Avian Flu case.
You Can Correctly Have You Can Correctly Have Second Thoughts About Flu Second Thoughts About Flu Immunization By Any Route Immunization By Any Route
If:If:• Egg Allergy• Thimerosol Allergy (Local Reaction)
CDC contends only those with life threatening reactions should avoid the flu vaccine
• Prior Episode of GBS-Peak Age 20-50-1 Additional Case Per Million
Flu Shot Safety InFlu Shot Safety InPregnancy and BreastfeedingPregnancy and Breastfeeding• Case Series of
2000 Pregnant Women Immunized-No Birth Defects
• No Issues With Any Trimester
• Breast Feeding Does Not Interfere With ImmunityNo Adverse Effects For Child
All this based on non-live vaccine!!!
LAIV=FluMistLAIV=FluMistLLive ive AAttenuated ttenuated IInfluenza nfluenza VVaccineaccine
• Replicates in Nose - Very Poorly in Lower Airways
• Hen Embryo Derived• Trivalent (Three Viruses Targeted)• Shedding For About 2 Days• Probability Of Transmission 0.58-
2.4%• Suitable For Age 5-49
LAIV Helps ChildrenLAIV Helps Children
• 87% effective against culture confirmed influenza in children 5-7 years
• 27% reduction in febrile Otitis Media (OM)
• 28% Reduction in OM with concomitant Antibiotic Use
• Decreased Fever and OM in those that did develop Flu
LAIV Helps AdultsLAIV Helps Adults
• Adults 18-49• 20% less Febrile Episodes• 24% Less Febrile Upper Respiratory
Illness Episodes• 27%Fewer Lost Work Days due to
Febrile Upper Respiratory Illness• 18-37% Fewer Days Of HealthCare
Provider Visits Due To Febrile Illness• 41-45% Fewer Days Of Antibiotic Use
LAIV Not For EverybodyLAIV Not For Everybody
• Specific Age Range
• Non-Pregnant• Not For ASA Users
(5-17 y.o.)• Immune Disorders• All The Other
Issues in “Second Thoughts” slide
Vaccine Roll OutVaccine Roll Out
August September
October November
December+
Vaccine release from manufacturer.
Vaccine release from manufacturer. High risk individuals that desire vaccine should get it to avoid missed opportunity
Prime season for vaccination. Health Care Workers and High Risk Individuals
General Population
General Population. Still Beneficial.Flu struck Alaska as late as August one recent season.
Avian Flu ContingenciesAvian Flu Contingencies
• Travel-Surveillance-Recalls-Travel Bans
• Anticipate Public Health Measures-Mass Transit-Schools-Roadways
• Employee Health-Emphasis on not increasing risk
• Prevention-Begins with Annual Vaccination-Scaled response with risk
Avian FluAvian Flu• An Influenza Type A virus• Normally infects Domesticated Poultry,
Shore Birds and Water Fowl, rarely humans and not usually spread human to human
• Different than the Circulating Human Influenza
• Possibly infects those with extensive contact with birds
• Since its not a viral type typically encountered by humans the potential for spread is greater (less immunity in humans)
Avian FluAvian Flu
• Birds that are infected with avian influenza viruses can shed virus in saliva, nasal secretions, and feces.
• Contact with feces or respiratory secretions is important in the transmission of infection among poultry.
• Between flocks, infection usually spreads due to movement of infected birds and the actions of humans in moving feedstuff, personnel, equipment, and vehicles into and from premises that are contaminated with infected feces or respiratory secretions.
• The duration that these viruses can survive in the environment depends on temperature and humidity conditions, but they may survive up to weeks in cooler and moister conditions (droppings.) 48 hr infectivity on smooth surfaces.
http://www.cdc.gov/flu/avian/professional/protect-guid.htm
Flu Pandemics: The TollFlu Pandemics: The Toll
• 1918-19 Spanish Flu 500K Dead in US 20-50M Worldwide
• 1957-58 Asian Flu 70K deaths US
• 1968-69 Hong Kong Flu 34K deaths US
Play DefensePlay Defense
• The Avian Flu Virus physically resembles the “common” Human Flu virus.– There are ways to block the virus’ attack– There are ways to avoid picking up the virus– A certain amount of Virus needs to get into you
to cause illness
What happens if you do What happens if you do not wash your hands not wash your hands
frequently?frequently?You pick up germs from objects and surfaces and then you infect yourself when you: -Touch your eyes -Or your nose -Or your mouth
When should you wash your When should you wash your hands?hands?
• You should wash your hands often. Probably more often than you do now because you can't see germs with the naked eye or smell them, so you do not really know where they are hiding.
• It is especially important to wash your hands – Before, during, and after you prepare food – Before and after you eat, and use the bathroom – After handling animals or animal waste – When your hands are dirty, and – More frequently when someone in your home is sick.
What is the correct way to What is the correct way to wash your hands?wash your hands?
• First wet your hands and apply liquid or clean bar soap. Place the bar soap on a rack and allow it to drain.
• Next rub your hands vigorously together and scrub all surfaces.
• Continue for 10 - 15 seconds or about the length of a little tune. It is the soap combined with the scrubbing action that helps dislodge and remove germs.
• Rinse well and dry your hands.
RememberRemember
• It is estimated that one out of three people do not wash their hands after using the restroom. So these tips are also important when you are out in public
Alcohol BasedAlcohol Based“Waterless” Hand Cleaner“Waterless” Hand Cleaner
• Useful if your hands are not visibly soiled
• Apply liberally and spread it as thoroughly and as long as possible.– Don’t wipe it off– Allow it to air dry
• Convenient, but can cause hand drying if overused.
Alcohol in Moderation?Alcohol in Moderation?
• A CDC Study Points Out That The Most Effective Concentration of Alcohol in a “Dry” Hand Sanitizer is 62% or More.
• Reynolds SA, Levy F, Walker ES. Hand sanitizer alert [letter]. Emerg Infect Dis. 2006 Mar. Available from http://www.cdc.gov/ncidod/EID/vol12no03/05-0955.htm
Creativity in Shared Surface Creativity in Shared Surface Handling Handling
• When it comes to entering the restroom:Make like a surgeon turn your back to the door and press in backwards
• When using the faucetTurn on with a clean towelTurn off with a clean towel
• When leaving the restroomUse a towel to open the door (there will be a receptacle outside the restroom)
• Use an elbow to press the elevator call button
GlovesGloves
• Nitrile gloves present a good barrier but you don’t want what’s outside to get on you.
• Taking off (doffing) PPE1)Gloves
Outside of gloves is contaminated!Grasp outside of glove at the wrist with opposite gloved hand; peel
offHold removed glove in gloved handSlide fingers of ungloved hand under remaining glove at wristPeel glove off over first gloveDiscard gloves in waste container
MasksMasks• The Flu virus is
suspended on some very small droplets.– Generated by talking, laughing,
sneezing or coughing.
• A surgeon’s mask helps keep out the larger droplets
• A N-95 mask will keep out the smaller particles
• Really no need for masks if 3 ft separation maintained
Surface CleaningSurface Cleaning
• As with hand washing time is an important factor.
• Match the cleaner with the surface.– Alcohol or baby wipes on vertical and odd shaped
surfaces (phones, push plates, computer keys/mouse etc.)
– Allow cleaner (Windex or Spectrasol) to pool on desk tops or tables
– Increased contact time helps!
Cough/Sneeze EtiquetteCough/Sneeze Etiquette
• Stop droplet spread at the source!– Cover your mouth and nose during a sneeze– Contain droplets in a tissue– Discard the tissue promptly– Wash your hands after the sneeze, cough or
“allergic salute.”
The MedicationsThe Medications
• Antivirals: TamiFlu and Relenza– Prevent Virus from exiting cells
• Vaccine – Trains your body to recognize and fight that
one variety of flu (or one that looks similar).– Need a best approximation of the current model
of virus.
TamifluTamiflu
• Oral capsule• >age 1 y• Once a day for prevention• Twice a day for treatment• Reduce dose in kidney failure• Level at same dose higher if taking
Benemid (a drug for Gout)• Adjusted dose for renal failure
RelenzaRelenza• Inhaled• Not for asthmatics other chronic lung disease• No track record for elderly and chronically ill
and those with hepatic failure.• Advice against use by those with renal failure• > age 5 y• Two puffs twice a day dosing for treatment• Two puffs once a day for prevention• Some lower airway spasm - deaths
Personal PreparationPersonal Preparation• Keep a supply of prescription meds current• Think Blizzard!
-Food -Water-Batteries
• Anticipate-Child Care Issues-Transportation/Commute Changes
• Cleaning Supplies-Alcohol Wipes-Dry Hand Cleaner (Purell)-Surface Wipes/Cleaner (Chlorox,Spectrasol)
Other Things You May Want Other Things You May Want To KnowTo Know
• Due to limited time I provide the following in note form….
FAQ on Flu VaccineFAQ on Flu Vaccine• I’m Sick Now Should I Get The Shot?
– Efficacy Not Affected By Illness– If you Do Have A Fever Or Other Problems It May Be Hard
To Sort Out If The Shot Or The Illness Caused The Problem
• I Had The Shot In The Early 80s It Made Me Feel Bad For 2-3 Days– Filtration Techniques Have Improved Over Time. In The
Early 80s There Were A Significant Amount Of Impurities That Made It Through Which Could Explain Feeling Out Of Sorts For a Few Days.
– Further Advances Post 1993 Have Greatly Reduced The Amount Of Reactions Seen.
FAQ ContinuedFAQ Continued• Last Year I Managed To Get The Flu Even
Though I Had The Flu Shot– I Would Argue That Your Course Was Shortened And Of Less
Severity Because Of The Vaccine– The Vaccine Makers Are Really In The Business Of Saving
Lives
• What About That Avian Flu-Will The Vaccine Help?– The Avian Strains Of Flu Are Often Different Than The Ones
The Vaccine Is Aimed Against– CDC Advises Those At Risk For Avian Flu To Get The Vaccine
Anyhow As It Could Make It Clearer What Illness Is At Work
The 2006-07 ModelsThe 2006-07 Models
Type A– Wisconsin 67/2005
(H3N2-Like)– New Caledonia 20/99
(H1N1-Like)
Alternate– Substitute for
Wisconsin:Hiroshima/52/2005 (H3N2-Like)
Type B– Malaysia/2506/2004
Alternate– Substitute for Malaysia
Ohio/1/2005
MasterMaster of of
Disguise Disguise
The characteristic "spikes" of the influenza virus are haemagglutinin. They radiate all over the surface and are interspersed (in some types) by clusters of neuraminidase. These (HA and NA) molecules are thought to pass through the envelope and interact with the underlying matrix protein, M1.The HA and NA are the targets for each year’s Flu Vaccine. These sites are under constant change.
Reyes SyndromeReyes Syndrome• Cause Unknown. • Link To Viral Illness + Aspirin• Children Under 16 • Severe increase of pressure in the brain• Abnormal accumulations of fat in the liver• Typically Intractable Nausea and Vomiting• Lethargy, Drowsiness's, Irritability, Disorientation.• Seizures Coma Respiratory Arrest • 60% Fatality Rate If Not Caught Early.
Gullain Barre SyndromeGullain Barre Syndrome• Literary Reference: The Character Faria in The
Count Of Monte Cristo -Alexander Dumas• Ascending Paralysis• Affects Mylein Sheath (Insulator) around
Nerves• 1-4/100,000 In US Annually• Onset Typically days to weeks after a viral
illness• Full recovery in 50-90% of people• Many cases coincident with 1976-77 Flu
Vaccine Campaign
Risk StrataRisk Strata
“Front of the Line”• Existing Conditions (Increased Risk)• Caregivers• Health Care Workers• Good Idea• General Population
“Back of the Line”
Increased RiskIncreased Risk
• > Age 65• Chronic-Care Facilities Resident• Chronic Disorders Pulmonary Or CV• Regular Medical
Follow-up/Hospitalizations Required • Age 6mo-18y On ASA (Reyes)• Pregnant During Flu Season• Children 6-23 mo.
Age>65Age>65
• 30% Effective in Preventing Flu Illness
• 30-70% Effective in Preventing Hospitalization
• 80% Effective in Preventing Death
Potential CarriersPotential Carriers
• Medical System• Nursing Home Employees• Assisted Living• Care Givers To Those At Risk• Household Contacts Of High Risk
Groups