Avian Flu
(updated 31st August 2007)
Keywords: simulating people, simulating crowds, simulating crowd dynamics
Resilience During Influenza Pandemic
By Lol Foster
Introduction
Although there have been a number of health scares in recent years (SARS, West Nile, etc.), and whilst those affected by these have been seriously traumatised, it has to be accepted that these outbreaks haven’t threatened our societies or lifestyles to the extent suggested by some. That we continue to survive the various threats which appear in the media can endow us with a false sense of security. Like the farmers in the “Boy that Cried Wolf” story, we stop to react with speed and alarm because we feel that we have experienced it all before, so why go through the anguish and panic for nothing?
In addition to this, many people feel that their life-style, culture, society etc. protect them from most of the worlds more destructive illnesses, and given the high-health standards and hygienic food preparation expected in developed countries this is an understandable perception.
However, very few people have escaped the discomfort of a common cold, and most have suffered the pain and weakness brought about by influenza. The term ‘flu’ is so commonly misused that many people don’t consider it a serious threat, and is often used to describe a cold or minor virus.
With this in mind, it can be suggested that the health authorities will have a significant task ahead of them when they endeavour to breakthrough the complacency and confidence to declare to society that there is a flu virus imminent which could seriously impact on many societies and cultures (hence the title ‘Pandemic’; an illness which could affect the world).
This document is an attempt to provide its readers with a few of the tools you and your organisation may require to survive the ‘Pandemic’ influenza.
Origins
Most people will have heard of the Avian (or bird) flu which has been present in the Far East for some time, and has previously been responsible for serious disruption to the Chinese poultry industry. Recent reports have indicated how poultry farmers in Europe are taking measures to prevent their flocks being infected, and it now appears that the virus has travelled to Turkey and Russia.
Initially, this infection could only be transmitted from bird to bird, but there is now significant evidence that it is mutating so that the infection can be passed from bird to human. There have been quite a number of human deaths in the Far East that have been attributed to the Avian flu virus.
It is predicted by many of the worlds leading health authorities that this virus will mutate again so that the infection could be passed from human to human.
It is not possible to predict when this mutation could occur, but it is anticipated that with the world being such a small place, given the high-speed, frequent transport links, the resulting virus will begin to infect Asia, Europe and North America in a matter of days.
Severity & Impact
In a typical year, influenza affects 5 – 10% of the population over a 6 to 8 week period during the winter months, and it is the elderly who are mainly at risk (it is estimated that 12,000 people die each year in England and Wales from influenza, the majority of these being elderly).
Working on the available information and from examining previous pandemics, health authorities, including the World Health Organisation (WHO), suspect that the infection rate could be much higher, and could be significantly different from the usual types of influenza we suffer:
It will not be seasonal
The existing flu vaccine is unlikely to be of much protection
The flu could attack our communities in one or more waves of between 12 to16 weeks each.
The second wave could be more severe.
Children and the working population could be at greater risk than the elderly population.
The elderly may have some immunity which they built up during exposure to a similar virus earlier in their lives.
There could be over 50,000 deaths in the UK alone
The WHO suggests that 25% of the population could be affected, although it could be higher or lower. Similarly, the mortality rate of those affected could vary between 0.37% to 2.5%. The estimate of over 50,000 deaths is based on 0.37% of fatalities where 25% of the population has been infected.
The accuracy of these figures very much depends on how the virus mutates and how infectious it becomes. Whilst these facts remain unknown the health authorities have been advised to plan for a 25% attack rate over a single wave.
Twenty five percent – It’s necessary to give that figure some thought in order to recognise the potential of the impact upon your home and your work.
25% of your work-force
25% of your family
25% of nurses
25% of doctors
25% of teachers
25% of drivers
25% pharmacists
25% of waste disposal operatives
25% of service and store workers
25% of IT engineers
25% of emergency staff
25% of utility workers
25% of bank staff
So twenty-five percent could have a significant impact on our daily routines, and individuals and organisations should consider their resilience against this illness.
It is unlikely that a vaccine will be available for quite some time, (possibly up to 6 months) as it cannot be developed until the full details of the virus have been discovered and analysed.
The Health Services could be heavily inundated, and may only be able to handle urgent and critical cases.
Consequential Absence
Planning for 25% absenteeism may not, however, be sufficient. It is estimated that Consequential Absence could take the absence rate to between 40 & 50%. Consequential absence occurs when employees:
Falsely report sick in order to care for infected relatives and children;
Falsely report sick in order to keep children at home to protect them from becoming infected at school;
Falsely report sick to reduce their own chances of being infected at work;
Falsely report sick to avoid the excess work-pressure caused by high absenteeism.
Increasing Resilience
Families and organisations should aim towards a level of self-sufficiency wherever possible. How this can be achieved depends upon their individual circumstances, but it is recommended that a close and critical examination takes place of those things that people take for granted, those facilities that people will assume will always be there.
The following examples are included to display what life could be like when these facilities are removed, and may encourage people to seek alternatives in order to increase their independence and self-sufficiency.
Example A:
The infection can be spread by touching a person or surface contaminated by infectious droplets.
Therefore one of the methods to prevent the spread of the illness is to regularly wash ones hands.
This is a simple and common task, which we do almost sub-consciously, but in order to consider your resilience examine the various assumptions involved:
Preventative Method – Wash your hands:
Assumption – water will be readily available, hot and clean:
Assumption – soap will be available, and remain available for delivery / replacement.
Assumption - Towels will be available.
Assumption – Towels will be cleaned and replaced to assist prevention of infection.
Assumption – Water will be available to launder towels.
Alternative – Hot-air hand-dryers
Assumption – Electricity will be available to power hand-dryers.
Alternative – Use of paper towels.
Assumption – Paper towels will remain available for delivery / replacement.
Assumption – Soiled paper towels will be hygienically disposed of.
Alternative – Obtain garden-type incinerator to dispose of used paper towels.
Alternative - Obtain disinfectant-impregnated sprays / tissues. Rub hands until dry.
Assumption – Such items will remain available for delivery / replacement
So, by critically examining the assumptions involved in washing ones hands, your final consideration may be ‘where do I put the ashes from the incinerator?’.
Example B:
The infection can be spread by droplets of infected fluids, which will be spread by coughs, sneezes, etc, even during conversation.
Preventative Method – Use handkerchiefs:
Assumption – Handkerchiefs will be cleaned & replaced to assist prevention of infection.
Alternative – Use paper-tissues.
Assumption – Paper tissues will remain available for delivery / replacement
Assumption – Soiled paper tissues will be hygienically disposed of.
Alternative – Use of commercially available face masks.
Assumption – Face masks will remain available for delivery / replacement.
Assumption – Face masks will be effective.
Assumption – Soiled face masks will be hygienically disposed of.
Alternative – Obtain garden-type incinerator to dispose of used face masks.
This critical examination may seem extreme and, at the moment, unnecessary, but to employ this level of thought to your daily routines will assist in developing your resilience and business continuity.
It is accepted that the loss of utilities such as water and electricity are at the very extreme end of the scale, but if one considers:
Drought – (predicted by utilities in September 2005);
50% loss of utility workforce during an extreme influenza pandemic;
50% loss of chemical and fuel deliveries
then the possibility of periods of utility-loss should not be totally ruled out.
Remember – that it is unlikely that the infection rate will reach 50%, but an infection rate of 25% could, by consequential absence, raise the absence level up to 40 - 50%.
Business Continuity
In advance of any outbreak, business managers should be considering:
‘What can we afford NOT to do whilst retaining our core function?’
Basically, what ancillary activities have become, through time, custom or tradition, but don’t actually contribute to the core business?
How can your business survive during a period where contact with colleagues / customers is severely reduced?
What could you be doing now to advise your customers / workforce of the contingencies you may introduce?
What can you remove from your working day without causing a negative impact?
Consider:
Breakfast meetings / lunch meetings;
Duplication of meetings (i.e.: Meetings which consist of the same individuals, but who meet under different titles / different agenda – Strategy Groups; Policy Groups; Tasking groups, etc).
Meetings for non-urgent projects;
Meetings which include briefings / updates which could be provided electronically.
(Enhanced use of e-technology should be accompanied by enhanced stringency and discipline. Email / texts etc can be misconstrued, resulting in friction and confrontation. Inferences, hints and ambiguous humour etc. should be avoided. E-briefings should contain fact only).
What percentage of your personnel could work from home?
What IT is needed?
How secure is that IT?
What checks / balances do you need to ensure that this isn’t abused?
Can you video-conference?
Can you web-cam conference?
Can you do this by landline or cell phone?
“What CAN’T we afford NOT to do to retain core business?”
Office Sanitation
How long is it since your telephones were sanitised?
How many germs can be stored in a phone mouthpiece?
Can your workforce effectively clean their own phones?
Can this be arranged / trained for now, without causing union / contract disharmony?
How long is it since your keyboards were sanitised?
The infection can be transmitted by contact.
Can your workforce effectively clean their own keyboards?
Can this be arranged / trained for now, without causing union disharmony?
Can you set a policy that staff use only their own desk-phone?
Can you set a policy that staff use only their own computer?
Can you suggest to staff that they don’t allow others to use their mobile-phone?
Catering
Do you have catering facilities?
What impact would the temporary suspension of restaurant / canteen facilities have on your catering workforce / general workforce?
If catering is ancillary to your core function can you survive without it?
If catering is your core function, what actions can you take to maintain a swift, safe and dynamic service during a crisis, which will add to your reputation as normality returns? How can you display that you are taking the outbreak responsibly, and that the precautions you are taking exceed the requirements set by legislation.
Is the import of sealed, microwave meals a temporary option?
Shared kitchens.
Many large offices / organisations have shared kitchens separate from their usual catering facilities. These can contain shared catering facilities, and washing and drying equipment,
i.e.: fridges, pots, pans, cutlery, cups, plates, pan-scrubs, dish-cloths, tea towels.
If it is not possible to guarantee that these items are totally sterile, employees should be encouraged to be self-sufficient during an outbreak. Options include:
bringing in hot water / soup in a flask,
using their own crockery
using their own cutlery
using their own dish-cloths – tea-towels, etc.
Employers may wish to consider the closing of such kitchens during an outbreak to reduce the possibility of contamination. Any such move should include a risk assessment of the consequences; for example, would employees bring toasters and kettles into their office space, increasing the chances of accident and fire?
Fleet vehicles
Although fleet vehicles may be regularly cleaned, the concentration is usually on the exterior. During any outbreak there needs to be more emphasis on the interior of the vehicle, employing alcohol-based wipes and sprays to ensure that all the surfaces are regularly sterilised.
Consideration could be given to issuing each vehicle with a supply of wipes / sprays so that each driver can clean the steering wheel, dashboard, handles etc, at the start and end of each working day.
Shared Public areas
Similar practices to the above should be considered at Reception desks / elevators / vending machines, toilets, etc.
Personal Services
In businesses where bodily contact is unavoidable, (physiotherapy, hairdressing, opticians, etc), face masks and the use of gloves should be considered by both employees and clients whenever possible in order to limit any spread of infection.
Home & Family
The critical thought processes suggested above are equally relevant to the home as they are to business, and occurrences which are taken for granted may have to be reconsidered.
During an outbreak consideration should be given to reducing social contact, so family and friend gatherings may need to be cancelled. Remember that a person can be carrying the infection for a number of days before the symptoms are seen.
During an outbreak the family GP will be under intense pressure, as will local hospitals. As far as possible, a family should aim for self-sufficiency, which will assist in minimising contact with infected people, in addition to reducing the pressure on the local health service.
Pain-killers and commercial flu and viral medications from pharmacies will assist in reducing the discomfort that may accompany the virus.
Individuals who require daily medication, which is ordered via repeat-prescriptions should liaise with their GP as to how this can be maintained during a flu outbreak.
In extreme circumstances:
families should consider the possibility of the partial loss of utilities, such as fresh water and electricity.
A system of waste disposal as discussed above should be considered, and alternative forms of heating food should be considered, (e.g.: Camping stove, BBQ).
Heating systems which don’t rely on utilities should be considered (Propane heating; coal fires).
Food deliveries to supermarkets may not be as regular as usual, placing certain staple items in great demand;
Remember that de-hydrated food requires clean water for preparation, and frozen food depends on electricity. Tinned foods usually require little cooking and can be stored indefinitely.
Battery-powered radios will ensure that householders can still receive updates should there be any power disruption.
Other forms of lighting should be considered, and it may be necessary to have a stock of torches, bulbs and batteries as a contingency. Any use of candles should be accompanied by an assessment of the fire risks involved.
In regard to all of the foregoing, panic-buying is not recommended, but the gradual creation of a contingency store of water, medication and foodstuffs can be undertaken without excessive cost and without causing a strain on the market.
The above text is advice only; it is not a direction, order and carries no lawful mandate. The author accepts no liability whatsoever for any action/accident/other outcome resulting from the text within this document.
Epidemic Modelling
Appropriate intervention can have significant impact on the severity or even likelihood of an epidemic. For example, inoculations reduce the susceptibility of the population and isolation (quarantine) reduces the infection rate. Both inoculations and isolation are a crowd management problems.
The Epidemic Model
There are four parameters in the epidemic model Susceptible, Exposed, Infective and Recovered.
Susceptibles (S) - those individuals who are able to contract the virus, either die or recover.
Exposed (E) - those individuals who are infected but not able to transmit the virus
Infective (I) - those individuals who are infected and are capable of transmitting the virus
Recovered (R) - those individual who have recovered from the virus
The virus contact rate is defined by the average number of effective virus transmissions per unit time. The virus is transmitted in proportion to the number of possible encounters between Infectives and Susceptibles. We define this rate as bI the average rate at which an infective comes into contact with a susceptible.
bI is the total contact rate – this has to be multiplied by the likelihood that the person contacted is non-infective (this is S).
The complex nature of this problem means that an appropriate plan could contain epidemics.