Avian Influenza - Bird Flu

H5N1 Avian Influenza
  • Influenza Facts
    • Influenza is the result of a viral infection
    • Influenza mutates easily and rapidly
    • 5 - 20% of the US population is infected each year
    • There are 200,000 infections and 36,000 deaths annually in US
    • The influenza virus is sub-micron in size

  • Three Classifications
    • Type B - Circulates widely in human population
    • Type C - Found in humans, pigs & dogs
      • Causes mild respiratory infections
      • Does not cause epidemics
    • Type A - Found in many kinds of animals, including ducks, chickens, pigs, whales, and also humans.
      • Birds only get type A
      • Most frightening of the three
      • Believed to have caused the 1918, 1957 and 1968 Pandemics
      • H5N1 Avian influenza is a type A flu

Influenza Classifications
Antigenic Shift

The genetic change that enables a flu to jump from one animal species to another, including humans, is called antigenic shift.

Modes of Transmission

  • Droplet Transmission 
    • Typically occurs within one meter of patient
    • Not a facility wide problem
  • Airborne Transmission
    • Droplet nuclei may travel through out facility
    • Airborne infectiousness may vary by patient




SARS - Severe Acute Repiratory Syndrome

Frequently asked SARS questions

Q:        What is SARS?

A:         The World Health Organization announced that a new pathogen, a member of the coronavirus family never before seen in humans, is the cause of Severe Acute Respiratory Syndrome (SARS).

Q:        How is SARS spread?

A:            According to the CDC the primary way that SARS appears to spread is by close person-to-person contact. Potential ways in which SARS can be spread include touching the skin of other people or objects that are contaminated with infectious droplets and then touching your eye(s), nose, or mouth. This can happen when someone who is sick with SARS coughs or sneezes droplets onto themselves, other people, or nearby surfaces. It also is possible that SARS can be spread more broadly through the air or by other ways that are currently not known.

Q:        What is a coronavirus?

A:            According to the Penn State Aerobiological Engineering pathogen database, Coronaviruses are one of the causes of the common cold. They account for about 15% of cases of the common cold. Coronaviruses can infect other animals besides humans but strains are general specific to one host.  Coronaviruses have an incubation period of 1 – 4 days and are 0.06-0.22 microns in diameter.

Q:        How is the spread of SARS prevented in healthcare settings?

A:         The CDC recommends that staff use standard precautions (e.g. Hand washing), contact precautions (e.g., use of gown and gloves for contact with the patient or their environment) and airborne precautions (e.g., an isolation room with negative pressure relative to the surrounding area).

Q:        Should patients suspected of having SARS undergo aerosol generating procedures?

A:         The CDC recommends that “aerosol-inducing procedures should be performed on patients who may have SARS only when such procedures are deemed medically necessary. These procedures should be performed using airborne precautions as previously described for other infectious agents, such as Mycobacterium tuberculosis; Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Health-Care Facilities.”

 Q:        Can airborne Coronaviruses be removed from the air by HEPA air purifiers?

A:         HEPA filters are 99.97% efficient removing particles 0.3 microns in size from the air.  Theoretically, 0.3 microns is the most penetrating particle size for HEPA filters.  Therefore, HEPA filters can be expected to be even more efficient on particles both larger and smaller than 0.3 microns in size.  We should expect then that HEPA filters would be effective in removing particles the size of Coronaviruses.

Click on the links to the right to download additional information regarding SARS.
Updated Interim Domestic Infection Control Guidance in the Health-Care and Community Setting for Patients with Suspected SARS
Infection Control Precautions for Aerosol-Generating Procedures on Patients who have Suspected Severe Acute Respiratory Syndrome (SARS)
Interim Domestic Guidance for Management of Exposures to
The products to the right may be useful in preventing the spread of SARS in your healthcare facility!
AeroMed 625W - Wall Mounted HEPA Exhaust Unit for Negative Pressure
AeroMed 625D - Ducted HEPA Air Purifier for Negative Pressure
AeroMed 625P - Portable HEPA Air Purifier (for recirculation or exhaust applications)