2009 pandemic h1n1 influenza virus
1 / 31

2009 (Pandemic) H1N1 Influenza Virus - PowerPoint PPT Presentation

  • Uploaded on

2009 (Pandemic) H1N1 Influenza Virus. Washington State Department of Health Based on slides from: Anthony A Marfin Marcia Goldoft. Outline. Influenza, the illness Seasonal vs. pandemic influenza Current pandemic situation reports What to expect this fall / winter Public health response.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' 2009 (Pandemic) H1N1 Influenza Virus' - imogene-pennington

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
2009 pandemic h1n1 influenza virus

2009 (Pandemic) H1N1 Influenza Virus

Washington State Department of Health

Based on slides from:

Anthony A Marfin

Marcia Goldoft


  • Influenza, the illness

  • Seasonal vs. pandemic influenza

  • Current pandemic situation reports

  • What to expect this fall / winter

  • Public health response

What is influenza like illness ili
What Is “Influenza-like Illness” (ILI)?

  • Virus causing two respiratory disease syndromes

    • ILI (upper respiratory tract)

      • Fever plus cough or sore throat

      • Lots of other symptoms

    • Severe acute respiratory illness (SARI)

      • ILI plus SOB, tachypnea, hypoxia

      • Lower lung involvement

  • ILI or SARI not only from influenza

You can have a mild case of influenza but influenza is not a mild illness
You can have a mild case of influenza,but influenza is not a mild illness.

Seasonal influenza viruses
Seasonal Influenza Viruses

  • Seasonal A H3N2, A H1N1, and B viruses spread by respiratory secretions

  • Toddlers, children, and adolescents transmit readily

    • Most cases in these age groups

  • Very young/old persons at risk forsevere illness

    • Most deaths in these age groups

  • Vaccine is the best and most cost-effective control

Each year seasonal flu accounts for
Each year, seasonal flu accounts for:

36,000 deaths

200,000 hospitalizations

20,000,000 ILIs

(may or may not be medically attended)

? Asymptomatic infections

Seasonal vs pandemic influenza
Seasonal vs. Pandemic Influenza

  • Every year, viruses change a little (“drift”)

    • Seasonal flu epidemics each winter

    • Quickly adjust vaccine annually

  • Rarely, viruses change a lot (“shift”)

    • Entirely new viruses so nobody immune

    • Spread easily among non-immune humans

    • Worldwide epidemic transmission (pandemic)

    • Develop new vaccine over many months

Pandemic influenza 1918
Pandemic Influenza 1918

Estimated 675,000 deaths / 105 million US population (0.6%)

Public health challenges compared to now: war troop transport, lack of health care, lack of public health planning, interrupted public services (garbage, mail, telegraph, telephone)

Deaths due to infectious diseases,

United States 1900-1994

Philadelphia was overwhelmed by the number of dead. Burials were done without coffins, eventually in mass graves dug by steam shovels.

1918 influenza pandemic

Influenza deaths 1918 compared to 1915
Influenza Deaths, 1918 Compared to 1915


Current situation united states and washington beginning april 2009
Current Situation United States and Washington Beginning April 2009

2009 pandemic h1n1 influenza virus

H1N1 2009 Influenza Virus Pedigree

2009 Human



Eurasian swine




Human “seasonal”




influenza viruses

“Triple reassortant”

Swine A/H1N2


North American swine



Human seasonal



2009 h1n1 influenza
2009 H1N1 Influenza

  • Entirely new virus so nobody immune

  • First identified in California and Mexico, April 2009

  • Initial investigations → virus found in many states

  • Summer 2009, worldwide spread

    • Globally, most flu cases due to 2009 H1N1

    • Flu pandemic declared by WHO June 2009

  • Flu cases in U.S. and Washington continued through summer into fall (unusual)

    • Severe cases and deaths

2009 pandemic h1n1 influenza virus

Risk for severe infections with 2009 H1N1

Lung disease (asthma, smoking, COPD)



Heart disease

Other chronic medical conditions

Neuro-developmental disease in children

2009 H1N1 Influenza

2009 pandemic h1n1 influenza virus

Flu virus testing in typical flu season in early 2009 with mix of seasonal H1N1, H3N2, Anot typed, and B viruses.

2009 pandemic h1n1 influenza virus

New mix of seasonal H1N1 virus in April.

What can we expect this winter
What Can We Expect This Winter? Washington 2009

More cases of flu than in typical years, particularly in younger ages

Absenteeism due to own or family illness

More deaths because more cases

More deaths in younger ages because more cases in younger ages

With seasonal flu, 90+ % deaths are ≥ 65 years

With H1N1 flu, 90+ % death are < 65 years

Public health response
Public Health Response Washington 2009

Components of response
Components of Response Washington 2009

  • Surveillance

  • Community Mitigation

  • Healthcare Planning

  • Communication

  • Continuity of Operations Planning

Influenza surveillance in washington
Influenza Surveillance in Washington Washington 2009

Mandatory reporting in Washington



Sentinel physicians, aggregate lab data, syndromic surveillance

Medically attended ILI

Community survey, school absenteeism

ILI cared for at home


Community mitigation
Community Mitigation Washington 2009

Interventions that lessen the impact of a pandemic

Community mitigation can include:

Non-pharmaceutical interventions

Isolation (ill)

Quarantine (exposed to ill)

School Closure

Community Social Distancing

Community Infection control

Pharmaceutical Interventions



Goals of community mitigation

2 Washington 2009



Goals of Community Mitigation

Delay outbreak peak

Pandemic Outbreak:

No Intervention

Decompress peak burden on hospitals/infrastructure

Diminish overall cases and health impacts

Daily Cases

Pandemic Outbreak:

With Intervention

Days Since First Case

What you can do
What you can do Washington 2009

  • Wash your hands.

  • Cover your cough.

  • Don’t touch your eyes, nose and mouth

  • Try to avoid contact with sick people.

  • Make a family plan.

  • Stay home if you’re sick.

  • Get vaccinated (flu and maybe pneumococcal).

Current cdc and doh community mitigation strategy for 2009 h1n1
Current CDC and DOH Community Mitigation Strategy for 2009 H1N1

  • H1N1 not severe enough for widespread community social distancing (e.g., school closures)

  • Protect overall public health by:

    • Reducing community transmission

    • Minimizing severe cases

    • Preventing social disruption

  • May change – influenza is unpredictable!

  • Still need to prepare for a major epidemic like 1918

Antiviral and vaccine distribution
Antiviral and Vaccine Distribution H1N1

  • DOH received antivirals and N95 masks from the Strategic National Stockpile (SNS) this spring

  • DOH receiving H1N1 vaccine this fall as available

  • DOH distributed antivirals and vaccine to LHJs

  • Monitoring the usage of antiviral medications

    • Usage has rapidly increased over the past few weeks

Acip target populations for h1n1 vaccination
ACIP Target Populations for H1N1 Vaccination* H1N1

  • Pregnant women

  • Household contacts and caregivers for children younger than 6 months of age

  • Healthcare and emergency medical services personnel

  • All people from 6 months through 24 years of age

  • Persons aged 25 through 64 years who have health conditions associated with higher risk of medical complications from influenza

*MMWR 2009;58:1-8

2009 pandemic h1n1 influenza virus

Dell Children's Medical Center in Austin is seeing hundreds of patients a day with flu-like symptoms and is preparing triage tents to handle the volume.

Hospitals are screening and limiting visitors.


Communication of patients a day with flu-like symptoms and is preparing triage tents to handle the volume.

  • Complex messages need to be communicated to the public and healthcare providers

  • Complex public messages

    • Disease severity

    • Seeking medical care

    • Vaccine safety

  • Complex healthcare provider messages

    • Purpose of the Public Health Laboratories

    • Treatment recommendations

2009 pandemic h1n1 influenza virus
COOP of patients a day with flu-like symptoms and is preparing triage tents to handle the volume.

Identify who will be affected

Plan for workforce reduction and support of workers

Cross-training for critical jobs

Consider flexible work schedules

Reduce spread of influenza

Promote cough etiquette and hand cleaning

Promote vaccination (flu and pneumococcal)

Provide routine environmental cleaning

Encourage use of sick leave for self-isolation at home

More information
More information of patients a day with flu-like symptoms and is preparing triage tents to handle the volume.

Washington State Department of Health


Local public health departments


Federal government


2009 pandemic h1n1 influenza virus

Thank you. of patients a day with flu-like symptoms and is preparing triage tents to handle the volume.