Rationale
The World Health Organisation has warned that there is a high risk of the avian influenza ("bird flu") becoming the next human influenza pandemic. The Ministry of Health (MoH) is constantly updating its pandemic influenza plan and leading whole of government work to prepare for a possible pandemic in New Zealand. All educational institutions must prepare in advance for the possibility of a pandemic
New Zealand Government preparing for an influenza pandemic?
New Zealand has been planning for an influenza pandemic for some time. The Ministry of Health is working with the health sector and other government agencies, including the Ministry of Education, to ensure New Zealand is as prepared as possible for a potential pandemic.
The Ministry of Health's National Health Emergency Plan: Infectious Diseases describes how Ministry of Health, health organisations and schools will function after a national health-related emergency is declared. District Health Boards, police, fire services and "lifeline utilities" are part of regionally-focused Civil Defence Emergency Management (CDEM) Groups.
National Emergency Plan / Alert Codes
The pandemic influenza section of theNational Health Emergency Plan is continually being updated and is available on the Ministry of Health website. The plan is based around "alert codes" which define the planning escalation steps for action in the event of a pandemic. Changes in alert codes will be widely publicised. Apart from alerting government agencies to action, the alert codes may provide your school with triggers to activate your own pandemic plans.
The Ministry of Health advises the potential effects of an influenza pandemic in New Zealand might be that:
· morbidity and mortality are unknown but may be very high
· full community mobilisation will be needed – all government and many community agencies are likely to be involved in the response
· health services may be unable to provide direct care (and the role of health care services may be to co-ordinate and support community mobilisation)
· periods of very high staff and student absence rates may be likely
· early childhood education services, schools and tertiary organisations may be closed to students for a period of weeks, impacting on the workforce and economy.
The following table shows the five stages of Ministry of Health pandemic influenza strategy and the "alert codes" that will signal a shift from one stage to the next.
New Zealand's Pandemic Plan
Table 1 Overall Influenza Pandemic Management Strategy and Associated Actions
Click to download the strategy table in word format[1] The transition from Code White to Red could be quite quick (that is, the Code Yellow stage could be short).
The decisions to move from Code White to Yellow, from Yellow to Red and from Red to Green, will be made by the Ministry of Health which will notify the public through its website and the media.
What are the powers of Medical Officers of Health in a pandemic emergency?
Activation of the National Health Emergency Plan begins when the Ministry of Health learns of a potential national health-related emergency, such as an influenza pandemic. Medical Officers of Health will be working as part of each district's and region's health response co-ordination team and have wide ranging powers designed to prevent the outbreak or spread of any infectious disease. These powers include the ability to:
· require people to submit themselves for medical examination
· require people, places, buildings, ships, animals, and things to be isolated, quarantined, or disinfected
· forbid persons, ships, animals, or things to be brought to any (air or sea) port or place in the health district from any port or place supposed to be infected
· forbid persons to leave a place or area until they have been medically examined and found to be free from infectious disease
· require theatres, churches, bars, clubs and other public gathering places to be closed
· prohibit the attendance of students under the age of 16 years in schools, Sunday schools, and other public places within the district have infected animals destroyed
Why prevent public gatherings and close schools?
During the 1957-1958 pandemic a World Health Organisation panel found that spread of the influenza within some countries followed public gatherings, such as conferences and festivals. This panel also observed that in many countries the pandemic broke out first in camps, army units and schools.
During the first wave of the Asian influenza pandemic of 1957-1958 the highest attack rates were in school-age students. A recently published study[2] found that during an influenza outbreak school closures were associated with significant decreases in the incidence of viral respiratory diseases and the need to access health care among students aged 6-12 years.
What does closure mean?
Closing schools to students would not necessarily mean that facilities would be closed in a quarantine sense. Staff may still go to work, work remotely, or carry out 'alternative duties' for other agencies with their board's pre-approval. Facilities may also be used for alternative purposes such as Community Based Assessment Centres (CBAC)[3].
The Education Act 1989 gives principals and boards powers to exclude particular students and staff or to close their school in certain circumstances:
· Section 19 provides that a principal may exclude a student who may have a communicable disease (communicable diseases are specified in the Schedule to the Act. Highly Pathogenic Avian Influenza or 'bird flu' (HPAI subtype H5N1) was added on 12 February 2004. In practice, schools would generally proceed subject to advice received from health authorities.
· Section 65E provides that a board may close a school in an emergency such as an epidemic.
· The Health (Infectious and Notifiable Diseases) Regulations place duties on schools, teachers and parents in the case of a pandemic.
· Regulation 14 provides that schools must exclude teachers and students who have an infectious disease.
Careful exercise of all these powers will be especially important in the "stamp it out" stage. Any decision by the board chair and principal to close the school should be based on advice from health authorities. Though schools in an affected area may be closed to students, schools in unaffected areas will be expected to maintain normal services. Ill-advised action such as an unnecessary closure would make life very difficult for the wider community.
How likely is an influenza pandemic?
The World Health Organisation (WHO) and Ministry of Health advise that it is certain there will be an influenza pandemic at some time in the future, but no-one can say when.
On average, influenza pandemics occur three times every century, but with no recognisable pattern in timing. In the last century, pandemics occurred in 1918-1919 (the "Spanish flu"), 1957-1958 (the "Asian flu"), and 1968-1969 (the "Hong Kong flu").
The WHO considers the risk of avian influenza morphing into the next pandemic to be very high. The H5N1 virus has recently expanded its geographical area: originally it had affected several east and Southeast Asian countries, central Asia, Europe and Africa[4]. Even if the risk from avian influenza goes away, another influenza virus can be expected to come along months or years later.
The WHO is advising Governments worldwide to take precautionary measures and develop pandemic influenza response plans.
What is avian influenza ("bird flu")?
"Bird flu" or avian influenza is a contagious viral infection that can affect all species of birds. Migratory waterfowl (ducks and geese) are a natural reservoir for avian influenza virus overseas and may carry the viruses without becoming ill.
Fortunately, New Zealand is not on the regular migratory pathways of any waterfowl and only very occasionally do waterfowl reach our shores, generally originating from southern Australia.
"Bird flu" outbreaks among chickens and other birds occur from time to time around the world due to a variety of strains of avian influenza virus.
The current outbreak of highly pathogenic avian influenza (HPAI) due to the H5N1 strain is of concern because of the size of the outbreaks, the number of countries becoming affected and the fact that humans have become infected.
The H5N1 virus is highly infectious among birds and in a number of species it can be rapidly fatal. Because of their living conditions domestic poultry flocks are particularly vulnerable to the rapid spread of the disease. The disease is not normally spread to humans but some cases have been reported. Most cases to date appear to have resulted from close direct contact with infected birds. There is no suggestion yet that the virus is easily spreadable from person to person.
Clinical experts are, however, concerned at the potential for H5N1 to adapt to humans and thereby acquire the ability to spread readily from human to human. If this happens there could be a worldwide influenza pandemic. The WHO considers the current risk to be high and is advising governments worldwide to take precautionary measures and develop pandemic influenza response plans.
Why should New Zealanders be concerned?
Beginning in late July 2005, official reports to the World Animal Health Organisation from government authorities indicated that the H5N1 virus had expanded its geographical range. Russia and Kazakhstan reported outbreaks of avian influenza in poultry in late July and confirmed H5N1 as the causative agent in early August. Deaths in migratory birds infected with the virus have also been reported. Outbreaks in both countries have been attributed to contact between domestic birds and wild waterfowl via shared water sources. These are the first outbreaks of HPAI recorded in the two countries. Both countries were previously considered free of the virus.
In mid-October, Turkey, Rumania and Greece reported outbreaks of avian influenza and confirmed H5N1 as the causative agent.
Experience in south-east Asia (Viet Nam, Thailand, Cambodia, and Indonesia) indicates that human cases of infection are rare but that there is a high mortality rate (there have been 218 laboratory-confirmed human cases of avian influenza since December 2003, of which 124 were fatal). Most, but not all, human cases have been linked to direct exposure to dead or diseased poultry, notably during slaughtering, de-feathering, and food preparation.
Influenza viruses are highly unstable. This means that over time viruses change and may develop the ability to readily infect humans. Also, when animal influenza viruses are circulating at the same time as human viruses there is potential for the two to "meet" and create a new influenza virus to which humans would have little, if any, protective immunity, and which can spread easily from person to person.
H5N1 is showing signs of changing and the expanding geographical presence of the virus creates expanded opportunities for human exposure. The emergence of an HPAI strain that is readily transmitted among humans would mark the start of a pandemic.
[1] The transition from Code White to Red could be quite quick (that is, the Code Yellow stage could be short).
[2] Heyman, A., Chodick, G., Reichman, B., Kokia, E., Laufer, J. (2004). Influence of school closure on the incidence of viral respiratory diseases among students and on health care utilization. The Paediatric Infectious Disease Journal. 23 (7), July 2004. This study is available on this website.
[3] In a pandemic emergency people with influenza symptoms will be encouraged to stay away from hospitals and doctors' surgeries, and to seek assistance at a Community Based Assessment Centre (CBAC). Some District Health Boards may consult with boards of some schools about using their school for this purpose.
[4] As at May 2006, the East Asian and South East Asian countries which have been affected are Japan, China, Korea, Laos, Vietnam, Thailand, Cambodia, Indonesia and Mongolia. The central Asian countries affected are Russia and Kazakhstan. European countries affected include Turkey, Palestine, Rumania and Greece. African countries include Egypt and Sudan.