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Avian flu five years on from FMD UK 2001:
have we learnt anything?
James Irvine
Teviot Scientific, Perthshire & Edinburgh
Filed 23 Feb 06
www.land-care.org.uk
Since 2003 the highly virulent H5N1 strain of
avian flu in south east Asia has passed from birds to over 100 humans.
Before reaching Lyon in the east of France - only some 400 miles
away from the UK -it has spread through Iraq, Nigeria, Azerbaijan,
Bulgaria, Greece, Italy, Slovenia, Iran. Austria, Germany, Egypt
and India (1). But our political
masters have kept reassuring us that the migratory patterns of birds
at this time of year would probably mean that the UK might be lucky
and get away with it. Or we might not.
Such was the situation also with Foot and Mouth
Disease (FMD) prior to 2001. Warnings that the UK was at high risk
from FMD were ignored. In spite of an earlier outbreak of FMD in
the UK in 1968 and the inquiry that followed, very few lessons had
been learnt when FMD struck again in 2001. The Northumberland Inquiry
Report had been left on the shelf and forgotten about. So when FMD
hit a dynamically changed livestock industry, basic mistakes in
the management of the outbreak were made with disastrous consequences.
FMD UK 2001 was followed by a spate of inquiries,
including those by the Royal Society of Edinburgh (2)
on which I was a member, and the Royal Society (3).
What is depressing is that some of the key recommendations
included in these inquiries relevant to any future outbreak of FMD
or other contagious viral disease of livestock, such as avian flu,
would appear not to have been implemented in spite of assurances
from the government authorities that they would be.
While there are important differences between
FMD and Avian flu, there are two key principles of management, common
to both diseases, that have not been adequately developed since
the lessons of 2001. These are:
1. the development of rapid on farm diagnostic
tests
2. the use of vaccination as a front line
tool.
Listening to recent reports on peak time TV one
hears again and again how
"samples have been sent to a laboratory
in England for confirmation.and
the results are awaited".
This is too reminiscent of FMD UK 2001 for comfort.
Both precision and speed of diagnosis are essential for the efficient
management of an outbreak, be it FMD, avian flu or any other. What
has conspicuously not happened is the development of known technology
for such important clinical use. Such a development was clearly
recommended in the FMD inquiry reports, and indeed was vociferously
called for during the FMD UK 2001 outbreak itself. The recent statement
by Dr Roger Breeze, previously director of the US Department of
Agriculture at Plum Island makes the point very clearly (4).
For the past five years the arguments have continued
over the question of "validation" of these tests. Why
this should be is difficult to understand. Perhaps interests other
than science are being allowed to influence progress to suit some
other agendas. It cannot be on account of a shortage of materials.
There has been plenty FMD and Avian flu around the globe to work
with.
Central to the FMD UK2001 outbreak were the protracted,
acrimonious arguments as to whether vaccination should or should
not be used, and under what circumstances. Misinformation about
the science of vaccination was rife, which reflected badly on certain
senior individuals within government, the scientific community and
those advising influential organisations (5).
Long after the event, it was Brussels through
its EU directive that insisted that vaccination must be considered
by member states as a front line procedure in any future outbreak
within the EU. Although included by mention in the UK's revised
contingency plans, to my knowledge no mock FMD exercise within the
UK has ever included vaccination. The weak excuse commonly offered
is that there are too many possible scenarios that it is best to
consider the situation when it arises. And so, when another outbreak
does occur, the acrimonious arguments, with "science"
being quoted to comply with various political, ideological or commercial
interests, will start all over again. Inevitable delays will result
at a time when well informed, precise and rapid decision making
is essential.
And so it is with Avian flu today. With years
of notice from epidemiologists, the UK is presently arguing in Brussels
as to whether vaccination against avian flu should be adopted or
not. France and Holland, among others, are in favour of vaccination
while the UK is arguing against it. The UK government Minister for
Animal Health, Ben Bradshaw has assured the nation on national TV
that Britain is well prepared for avian flu: "among the best
in Europe" he said. The latest developments are that the EU
has given permission with certain restrictions to both France and
Holland to use vaccination for H5N1 strain of Avian flu, while it
transpires that the UK may not even have stocks - or sufficient
stocks - of an appropriate type of vaccine for the purpose.
But listening to the arguments against vaccination
on national UK TV forwarded by certain so-called scientists (and
indeed holding senior official positions in the veterinary world)
makes one cringe. Frankly, the interviewer seemed to have a better
grasp on reality than certain of the experts interviewed. Lack of
trust in veterinary officialdom is not helped by the fact that some
months ago the authorities managed to put together birds in quarantine
from widely different geographical areas, and then pool their test
samples. When a positive result was recorded the authorities did
not know from which bird, or indeed from which country the highly
virulent H5N1 virus had come.
When a more than credible expert, John Oxford,
professor of virology at St Barts Hospital, London took a different
view from the government's position regarding vaccination and biosecurity
measures (such as housing free-range poultry), his advice was dismissed
publicly by our Animal Health Minister as being "out of line
with the opinion of the majority of experts".
The problem for Minister Ben Bradshaw (and his
boss Margaret Beckett as head of DEFRA) is that another highly credible
virologist, Professor Oosterhius of Rotterdam, Holland just happened
to be expressing similar logic to that of Professor Oxford on the
same day on another TV programme. No doubt the internationally respected
Dutchman would not be included among Bradshaw's selected advisers.
Good science is an international activity with high ethical standards:
not run in the manner of a petty political party pressure group.
The main argument currently put forward by some
UK officials is that vaccination for Avian flu, unlike other types
of vaccination for other diseases, only masks the symptoms, preventing
the birds from dying but still enabling them to retain virus and
to spread it to other birds, albeit in reduced amounts. As a result,
as described on DEFRA's website, clinical symptoms important in
diagnosis may be lost. All this is reminiscent of similar arguments
put forward against vaccination in FMD UK2001. The fact that such
a vaccine considerably reduces the viral load and that infected
birds can be distinguished from vaccinated ones if marker vaccines
are used (6) does not get a mention.
Likewise no reference is made to the use of sentinel birds. No one
is suggesting that vaccination alone is the answer, but it is a
highly useful tool in conjunction with biosecurity and focused culling.
But when pressed by the interviewer with the evidence
that vaccination for Avian flu in Vietnam has been successful, in
conjunction with biosecurity measures and focussed culling, it transpires
that the UK expert is referring to "the use of avian flu vaccine
that is currently available in the UK". That again was a key
problem in FMD UK2001. Then, as now, those in authority - or advising
authority - appear to be talking about vaccines that are far from
modern and which may not use modern technology. Just why cannot
such persons be open about the matter? Or does their favoured position
with government (either directly or indirectly) prevent them from
doing so? (7).
Modern Avian flu vaccines can greatly reduce the
viral load and they can allow vaccinated birds to be distinguished
from those that carry infection. What is apparently lacking is an
openness by the UK authorities as to exactly what kind of vaccine
they have stocked for possible use in the UK. To add to the confusion
national TV on the 22nd February 2006 stated that they had just
been told by government that they did not hold any stocks of vaccine
to counter an attack of Avian flu in the UK. One of the clear recommendations
of all the inquires that followed FMD UK2001 was that there should
be clear and effective lines of communication between the authorities
and the public, and that stocks of vaccine should be sourced in
preparation to help cope with a potential threat.
The argument within the UK goes on to say that
"it will take 3 weeks for a vaccine to
work, and since the incubation period of the disease in chickens
is 2- 3 days the infected birds would all be dead by the time
the vaccine could be effective".
But that is why it is so important to anticipate
the size of the risk and use vaccination at the appropriate time,
and to use an appropriate vaccine that embraces modern vaccine technology.
To that end it would be useful to know where Britain's poultry are.
Until recently there hasn't been any register. The closing date
for registration - in the government's hasty effort to correct this
staring omission - is 28th February 2006.
Another problem that causes much confusion in
the minds of the public, and I daresay poultry farmers, is ex-cathedra
statements by key executive personnel in important organisations
who may themselves have little understanding of viral biology. One
such figure is widely quoted as saying that
"vaccination would not work because there
are too many types of avian flu virus".
We heard a similar argument with FMD, but the
fact is with Avian flu there is but one type that is highly lethal
to birds, and it is the same single type that, through a minor transformation,
has been involved in the transmission of the virus to man and the
consequent human fatalities.
As with FMD UK2001, there were those who argued
against vaccination because it would take too long to do the vaccinations
in such high numbers, would be expensive and would disrupt trade
in terms of loosing FMD-free status (based on EU rules that had
not kept up with advances in technology). So it is today with regard
to vaccination for Avian flu. Today's poultry industry is big business
and vaccination against a range of viral diseases is routine, just
as in other aspects of the livestock industry. Avian flu vaccine
is no more expensive than other vaccines in routine use.
Again, on national TV a poultry farmer, who claimed
he was doing good business selling "organic" free range
eggs, was not prepared to consider vaccination because it was "against
the ethos of the "organic" movement where everything had
to be 'natural'". So he, and supposedly the branch of the organic
movement that he belonged to, were happy to put other poultry farms
at risk because of the unproven health benefits of their organic
farming marketing strategy. It should be said in fairness that not
all branches of the "organic" movement take such a view.
Given the proper information the British public are quite intelligent
enough to recognise that it might well be better for free-range
hens to be housed when they are threatened with a deadly virus from
birds in the wild.
Then, again on national TV at peak viewing time,
along came a chicken farmer who handled thousands of chickens with
a very short time between acquisition of chicks and their processing
for the food chain. He was an intensive breeder of chickens. He
reckoned that DEFRA had got it right in avoiding vaccination. But
what did it matter to him if he got wiped out for a week or two
with a slaughter policy: he would be up and running again with compensation
in no time. Again, a very narrow and selfish attitude, reminiscent
of the pedigree cattle breeders in FMD UK2001. They wanted FMD-free
status to be restored as soon as possible to enable them to export
cattle genetics: EU rules at the time were such that vaccination
would delay such an opportunity. So they opposed vaccination.
Hopefully the biosecurity measures drawn up by
DEFRA will play their part in controlling an outbreak when it occurs.
In contrast to FMD, Avian flu virus is transmitted between birds
by close contact and through their droppings but not by aerosol.
FMD can be transmitted by wool and Avian flu by feathers. The spread
of Avian flu to poultry across continents is primarily through wildlife
in the form of water fowl and waders. That means ducks and swans
among others. Poultry are particularly vulnerable. Bird migratory
patterns are therefore important, and these can be variable according
to the prevailing weather.
It should also be remembered that not only are
poultry very susceptible to catching the virus, but they themselves
are leaders in the migratory stakes through cross border trade (legal
or otherwise) both within and outside the EU. While trade from outwith
the EU has been officially stopped, the only restrictions within
the EU that are in place are movements from areas where an outbreak
of Avian flu has already occurred. The extensive and lucrative trade
in exotic birds such as parrots is also a worry.
As already mentioned, an important biosecurity
measure would clearly be to keep poultry housed when there is significant
risk of infected migratory birds being in the vicinity in the near
future. But here again the pronouncements of the Minister for Animal
Health, Ben Bradshaw are little short of breathtaking.
"We will not instruct poultry farmers to
house their birds until such time as infection arrives in the
UK. It has not happened yet and it may not happen. We need to
vigilant in the lookout for it. Look what happened in Holland.
They housed their poultry, Avian flu never arrived and they had
to let all the birds out again - what a waste".
Ben Bradshaw, UK Minister for Animal Health
But there are serious problems with our government's
strategy of waiting for infection to arrive in the UK before taking
any action. Quite apart from negating much of the value of vaccination,
it seems to assume that the infection may arrive in one, or at worst
only a few, localised areas and that extensive culling in the vicinity
should sort the problem. The authorities point to the last time
Avian flu hit the UK in 1992. It only affected one area and culling
did indeed sort it. But Avian flu in 2005/2006 presents a very different
scenario on account of its massive global aspects and rate of spread.
The virus may become endemic in certain areas (such as East Africa)
where there is continual close contact between poultry and people.
This increases the possibility of mutation - so characteristic of
viruses given the right conditions - enabling the virus to more
readily transmit to man, and then from man to man, and so to a catastrophic
human pandemic on account of its virulence. Again in contrast to
1992, the movement of people and the trade in birds around the globe
is vastly greater with very short time scales. Reducing the viral
load of this highly infective virus would be an important step in
reducing such serious risks.
Rather than mocking the Dutch they should be complemented
on sensibly applying the precautionary principle.
The situation described in this article reflects
badly on the approach by the UK government to important issues pertaining
to animal health. Although there are no risks from eating well cooked
chicken, there are implications for food security (when extensive
culling is the preferred option for disease control) and for the
health of its people (when there is a risk of viral mutation).
February 20th 2006 marked the fifth anniversary
of the official notification of the outbreak of FMD in the UK. The
FMD crisis of 2001 cost an estimated £8billion, wrecked havoc
on farming and the countryside with the unnecessary slaughter of
many millions of livestock and huge stress to the people involved.
Newcastle University's Centre for Rural Economy recently produced
a report to mark this anniversary, commenting on the legacy of the
FMD UK2001 crisis for farming and the British countryside (8).
It was not complimentary. Thus it states:
"The UK's approach to combating animal
disease has remained broadly the same since the FMD crisis. Stamping
out is the basic philosophy, through culling of infected animals
and those that have been at risk of being exposed to the disease.
Vaccination remains a theoretical option"
"After having planned to establish a Department
of Rural Affairs to improve the treatment of rural affairs policy
issues across government, the unanticipated outcome of the 2001
post-Election reshuffle was the creation of Defra with its environmental
protection and climate change responsibilities. The result has
been the reverse of what was intended, and the treatment of rural
affairs within central government has been marginalised as a result"
"DEFRA is a large aand sprawling ministry
in which rural affiars have, perversely, been been eclipsed"
"In the light of the difficulties in raising
the profile of rural development issues in Whitehall and the regions
and of indicators about the state of health of some local rural
economies, the fifth anniversary of the FMD crisis would be an
opportunity for the Government to review DEFRA's rural economy
remit".
Writing in The Times, Magnus Linklater summarises
much of the above with characteristic clarity (9).
There have been influenza
pandemics roughly three times a century since at least the 1600s.
It appears inevitable that there will be further pandemics in the
near future. Even though there is as yet no confirmed cases of human-to-human
transmission arising from a mutation within the H5N1 strain of the
Avian flu virus, the evidence suggests that the world is closer
now to a pandemic than at any time since the 1960s. It would be
wise, therefore, if the UK, along with its fellow EU member states
and beyond, would take a more proactive part in the control of threatening
viral diseases.
©www.land-care.org.uk
References
1. WHO (2006). Avian influenza
- spread of the virus to new countries. 21 Feb 2006.
http://www.who.int/csr/disease/avian_influenza/country/en
2. Royal Society of Edinburgh
(2002). Inquiry into Foot and Mouth Disease in Scotland 2001.
http://www.royalsoced.org.uk
3. Royal Society (2002).Infectious
diseases in livestock.
http://www.royalsoc.ac.uk
4 Breeze, Roger (2006).
PCR tests to enable diagnosis in a range of infectious animal diseases
- with particular reference to Foot and Mouth Disease.
Letter to Mary Critchley, editor of www.warmwell.com
Click
Here to View pdf
5. Irvine, James (2001). Vaccination
for Foot and Mouth: a personal view.
Scottish Farmer, 27th October, 2001
6. van Aarle, P. (2006). Making
avian influenza vaccines available, an industry point of view.
In: International Scientific Conference on Avian influenza.(Editors
Schudel, A. and Lombard, M.)
Dev. Bio. (Basel), Basel, Karger, 2006, vol 124, pp 151-155.
7. Irvine, James (2006). Peer
review of science is not always as independent as it is sometimes
claimed to be.
See SCIENCE Homepage, filed 14 Feb 06, www.land-care.org.uk
Click
Here to View
8. Donaldson, A, Lee, R., Ward,
N. and Wilkinson, K (2006). Foot and Mouth - five years on: the
legacy of the 2001 Foot and Mouth Disease crisis for farming and
the British countryside.`
Centre for Rural Economy Discussion Paper Series no 6.
http://www.ncl.ac.uk/cre/publish/discussionpapers/pdfs/dpb.pdf
9. Linklater, Magnus (2006). A
solution any birdbrain should see: as avian flu can spread unpredictably,
vaccination is the humane and intelligent option.
See ANIMAL HEALTH - GENERAL Homepage, filed 22 Feb 06,
www.land-care.org.uk Click
Here to View
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