avian influenza pandemic an ohs perspective

Avian Influenza PandemicAn OHS Perspective

Presentation to the

Commonwealth Safety Management Forum

23 November 2006

Brian Ewert

Presentation Overview

Part 1:• What is Avian Influenza?

• Avian Influenza within Australia

• 20th Century Pandemics

• 21st Century Epidemic

• H5N1 History & Epidemiology


Part 2:• The Key Facts

• What is the Risk?

• Antivirals

• Vaccines


Part 3:• Pandemic Preparedness

Part 4:• OHS Considerations

Part 5:• CSMF Assistance

Part 6:• Open Forum

Part 1

What is Avian Influenza?

Avian Influenza within Australia

20th Century Pandemics

21st Century Epidemic

H5N1 History & Epidemiology

What is Avian Influenza?An infectious viral disease that

primarily affects birds:• chickens• turkeys• pheasants• quail• pigeons• ducks• geese• guinea fowl• ostriches• sea birds• migratory waterfowl

& less commonly:• rats• ferrets• white rabbits• pigs• tigers• leopards• domestic cats

& rarely:• humans

What is Avian Influenza?

There are numerous strains and subtypes of the virus.

Strains vary from low to highly pathogenic.

Highly pathogenic avian influenza was first identified 1878.

4 strains are known to cause human infection.

Only H5N1 is currently linked to severe human infection and death (rare).

All human cases of avian influenza have coincided with outbreaks in poultry.


Historically Australia has experienced avian influenza ‘outbreaks’:

1976 Melbourne Suburbs, Victoria (H7N7 strain)1985 Bendigo, Victoria (H7N7 strain)1992 Bendigo, Victoria (H7N3 strain)1994 Lowood, Queensland (H7N3 strain)1997 Tamworth, New South Wales (H7N4 strain)

To date no human avian influenza cases have been reported within Australia.


Highly pathogenic avian influenza in humans is subject to quarantine control (Quarantine Act 1908).

Since February 2004:

• Australia’s ‘pandemic alert phase’ has remained unchanged (‘Australia 0’ – no circulating animal influenza subtypes in Australia that have caused human disease)

compared with

• the Global ‘pandemic alert phase’ has remained unchanged (‘Overseas 3’ – human infection overseas with new subtypes but no human to human spread or at most rare instances of spread to a close contact)


1918 – 1919 ‘Spanish Influenza’:• H1N1 strain• estimated 40 – 50 million deaths

1957 – 1958 ‘Asian Influenza’:• H2N2 strain• estimated 2 million deaths

1968 – 1969 ‘Hong Kong Influenza’:• H3N2 strain• estimated 1 million deaths


31 influenza pandemics have occurred since the middle ages.

On average an influenza pandemic occurs every 30 years.

21st Century Epidemic

2002 – 2003 ‘Severe Acute Respiratory Syndrome’:

• 26 countries (Western Pacific regional focus)

• coronavirus (not avian influenza)

• 8098 ‘probable’ cases (774 deaths)

• raised awareness of the social and economic impacts of epidemics


1997 ‘Avian Influenza’:• Hong Kong• 18 cases (6 deaths)• notably 1.5 million birds were culled within 3 days

2003 ‘Avian Influenza’:• China & Vietnam• 4 cases (4 deaths)


2004 ‘Avian Influenza’:• Thailand & Vietnam• 46 cases (32 deaths)

2005 ‘Avian Influenza’:• Cambodia, China, Indonesia, Thailand & Vietnam• 97 cases (42 deaths)


2006 (to 13 November 2006) ‘Avian Influenza’:• Azerbaijan, Cambodia, China, Djibouti, Egypt, Indonesia,

Iraq, Thailand & Turkey• 111 cases (75 deaths)

Since 2003, human H5N1 mortality rate approximates 60%.

Part 2

The Key Facts

What is the Risk?

Antivirals

Vaccines

The Key Facts

Avian influenza and human influenza are different diseases.

Type ‘A’ influenza viruses:• occur in birds and mammals (humans)• cause ‘flu’• can cause a pandemic (rare)

Avian influenza is a type ‘A’ virus.

The Key Facts

Type ‘B’ influenza viruses:• occur in humans and dogs• cause seasonal ‘flu’• do not cause pandemics

Type ‘C’ influenza viruses:• occur in humans only• cause the common ‘cold’• do not cause pandemics

The Key Facts

Human avian influenza (H5N1 crossing the species barrier) is primarily attributable to direct human contact with infected birds:

• slaughtering, defeathering, butchering and preparation of infected poultry for consumption

• children playing in areas frequented by infected poultry

• domestic utilisation of water contaminated by the carcasses of dead infected birds

• chickens/ducks/turkeys/geese… penned together in unhygienic conditions spreading infection

The Key Facts

The Key Facts

Human to human transmission:• is possible• in rare cases is suspected (2004 Thailand – ill child to

mother, and 2006 Indonesia – amongst 8 family members)

• has not been sustained

Importantly: • H5N1 has yet to acquire the ability to spread efficiently

amongst humans

The Key Facts

If avian influenza pandemic was to occur:

• it is most likely to occur overseas amongst poverty stricken rural and periurban communities

• any spread to Australia would most likely be attributable to international travellers

Avian influenza may not evolve into a pandemic virus.

It is not possible to predict if/when a pandemic may occur.

What is the Risk?

If the avian influenza mutates (emergence of a ‘new’ strain) there is a risk of:

• human to human transmission

• virus rapidly spreading

• severe infection persisting and recurring in waves

• from ‘status quo’ to influenza epidemic and possibly a pandemic within 20 – 30 day window

Antivirals

Clinical data supporting the effectiveness of antivirals as a treatment of avian influenza is limited.

Antivirals may shorten the duration and lessen the symptoms of avian influenza.

Timing of administration appears critical (48 hour ‘window’).

Unnecessary antiviral use is linked with drug resistance.

Antivirals are currently available by prescription only.

Vaccines

Vaccines trigger an immune response bolstering the body’s ability to ‘fight’ an infection.

Vaccine production cannot usually commence until a virus ‘outbreak’ (the virus strain must first be identified).

Large scale vaccine availability is unlikely until after the first wave of infections.

Part 3

Pandemic Preparedness


8 steps to preparing for a pandemic:

1. Obtain senior management commitment and secure allocation of resources.

2. Form a pandemic planning team.

3. Develop pandemic business continuity plans.

4. Form a ‘crisis’ pandemic management team (with requisite delegations).


5. Undertake workforce planning (skills inventory).

6. Develop and implement an employee communication strategy.

7. Test the effectiveness of preparations.

8. Test employee confidence.

Part 4

OHS Considerations:

Employer’s Duty of Care

Employees’ Duty of Care

Consultation

Risk Management and Hierarchy of Controls

OHS Considerations

Under Part 2 ‘OHS Act’, employers are required to:• take all reasonably practicable steps to protect the health and

safety at work of their employees.

Therefore:• employers should anticipate risks associated with a potential

influenza pandemic (ie: risk management)• health and safety of employees should be integrated into

business continuity planning for pandemic influenza

However, in a pandemic scenario what constitutes ‘reasonably practicable’?

OHS Considerations

Under Part 2 ‘OHS Act’, employees are required to:

• cooperate with their employer’s reasonable instructions and policies (including risk control)

• take all reasonably practicable steps to ensure any action or omission does not create or increase a risk to health and safety

Therefore:

• employees should comply with the pandemic health advice and emergency directives issued by their employer and employers should ensure directives comply with public health advice/emergency measures

OHS Considerations

Under Part 3 ‘OHS Act’, employers are required to:• consult employees when assessing risks to health and

safety

Therefore:• employers should consult widely utilising existing

workplace arrangements (HSR and OHS Committees)• employers should provide accurate and current

information and education to employees addressing how a pandemic influenza may affect their work arrangements

OHS Considerations

Risks associated with an influenza pandemic can be categorised into:

• the direct risks of infection (contact, airborne droplet and aerosol transmission)

• indirect risks arising from changes to usual work arrangements

Question: How useful is the traditional ‘hierarchy of controls’ when planning for a pandemic (where do antivirals/vaccines ‘fit’)?

OHS ConsiderationsElimination – ?

Substitution – ?

Isolation – ‘clinical’ quarantine

Engineering – improve ‘natural’ ventilation of enclosed workplaces

Administration – cough etiquette, promotion of personal hygiene, additional workplace cleaning, home quarantine

PPE – mask/goggles/gloves/gowns

Part 5

Commonwealth

Safety

Management

Forum:

How can you assist?

CSMF

Challenge:• integrating OHS risk management into business

continuity plans (an employer responsibility)

Objectives:• assist with across-government consultation (emphasis

on health, safety and welfare of employees)

• develop consistent whole-of-government OHS ‘people management’ influenza pandemic guidelines

CSMF

Scope:• social distancing• cough etiquette• personal hygiene• cleaning/disinfecting the

workplace• managing workplace

entry• teleworking• contract management • minimising unnecessary

absenteeism

• managing staff who become ill at work

• provision & utilisation of PPE

• home quarantine• managing psychological

anxiety• emergency HR

delegations• training & communication• …

Open Forum

Questions & Answers

Discussion

Nominations – CSMF AIP Sub-Committee

Enquiries:

Brian Ewert

6225 8963

[email protected]

mailto:[email protected]

avian influenza pandemic an ohs perspective

Documents

avian influenza outbreaks

human cases of avian

human avian influenza

deaths2005 avian influenza

avian influenza pandemican

days2003 avian influenza

spanish influenza

asian influenza