Vaccine will take 3-5 years to complete safety testing
January 16, 2008. Times Online
Call for more bird flu vaccine as fourth
swan dies at Abbotsbury reserve
A fourth swan from the Abbotsbury swannery in Dorset is believed to have been infected with
the deadly H5N1 avian flu virus. The result is to be confirmed today by the Department for Environment, Food and Rural Affairs
The mute swan was found dead on Friday and sent for testing to the Veterinary Laboratories Agency
Government vets are not surprised by the further case and believe it is likely that other swans
at the important reserve near Chesil Beach may be infected.
It is not known precisely how the virus arrived in the area, though the most plausible explanation
is that a duck or similar species arrived from across the Channel during the cold snap before Christmas. The birds at the
swannery are fairly static and do not migrate.
Among the brids that migrate to the UK when there are cold spells on the Continent are mallard,
teal, widgeon and pochard as well as gulls.
John Houston, general manager at Abbotsbury Tourism, said that the latest case delayed a return
to normal business. “It puts us back to square one in terms of waiting for a 21-day clearance before we are out of the
woods,” he said.
“It's disappointing but not totally unexpected this early in the outbreak. It would be
wonderful if it disappeared immediately but that's unrealistic. It's going to take a while for it to be contained and weeded
The all-clear will be given only after 21 days have passed without any new bird infected with
the virus at the swannery.
Abbotsbury is one of the most popular tourist attractions on the south coast and is due to reopen
to the public on March 15 after the winter.
It has been owned by the Ilchester Estate since the 1540s though the swannery was established
by Benedictine monks who built a monastery at the site in the 1040s.
There is some relief that there is no evidence of the virus being endemic in wild birds in the
area. Similarly, the virus has not been found in any chick on a commerical poultry farm or backyard flock in the area.
The existing control and monitoring zones are to remain in place. There are some 32 premises
within the zone, of which 19 are free-range operations, involving a total of 24,588 birds.
In the wider monitoring area there are 34 farms, of which 17 are free-range, with a total of
Fred Landeg, the acting Chief Veterinary Officer, is appealing to anyone in the area who might
own a small number of chickens to come forward so that their birds and premises can be checked.
All birds inside the control zone - which extends 15 miles southeast of Abbotsbury and includes
Weymouth, Chesil Beach and Portland Bill - must be kept indoors. Owners are also advised to keep poultry away from wild birds
in the larger monitoring area, which extends to some 20 miles and includes the town of Dorchester.
Under current government regulations only owners with more than 50 birds must enlist to the
official poultry register, but others are encouraged to do so voluntarily.
France has raised the level of alert for a lethal avian flu outbreak as a result of the British
outbreak and ordered all birds to be locked indoors in areas near lakes, ponds and the coast. Defra said there were no such
plans in Britain.
The new outbreak has renewed calls for the routine vaccination of all free-range, organic and
hobby birds against the deadly flu virus.
The Elm Farm Organic Research Centre has been campaigning for such a preventive strategy for
more than two years. Defra has a stock of 10 million does of vaccine but so far they have been offered only for use to save
rare birds and collections in zoos.
Richard Sanders, senior policy researcher at the centre, said the latest outbreak at Abbotsbury
was now “a trigger point” and gave a definite indication the virus was circulating in wild birds.
He urged Defra to release its stocks of H5N1 vaccine to start an orderly programme of preventive
treatment.The alternative to vaccination was to lock up all birds a move that was “unacceptable, impractical and with
some species such as geese, impossible”, he said.
“When the national mood, as voiced so loudly by Jamie Oliver and Hugh Fearnley-Whittingstall,
is for quality, high-welfare poultry production, then we must do everything in our power to protect and grow the sector.”
TIMESW ONLINE, JAN 4, 08, Nigel Hawkes, Health
New vaccinations give scientists
hope of conquering flu pandemic
vaccine that could help to control a flu pandemic has shown encouraging results in its first
The vaccine, made by Acambis, based in Cambridge, should
protect against all strains of influenza A, the type responsible for pandemics. Unlike existing vaccines it does not have
to be reformulated each year to match the prevalent strains of flu, so it could be stockpiled and used as soon as a pandemic
strain emerges. Nor does it need to be grown on fertilised chicken eggs, as the existing vaccines do, but can be produced
by cell culture.
The results, announced yesterday by Acambis, show that in human volunteers the Acam-Flu-A vaccine was safe and produced an immune response against its target, a small protein (peptide)
called M2e that
is found on the surface of all A-strains of the flu virus. The vaccine was also tested on ferrets, which are commonly used
in flu research because they are susceptible to human and bird flu.
The ferrets were divided into two groups and either vaccinated with the new vaccine or left
unvaccinated. They were then exposed to a large dose of the H5N1 bird flu that has killed millions of chickens and more than
200 people across Asia since 2003. All the unvaccinated ferrets died, but 70 per cent of the vaccinated ones survived.
A significant problem with conventional vaccines
is that they attack parts of the flu virus that can change rapidly. Each season the World Health Organisation identifies the three strains
that are circulating, normally two A-strains and one B, and the vaccine is made to order to provide protection against them.
It is always a race against time, because millions of eggs have to be produced to grow the vaccine and if it is not used it
is out of date by the following season.
Acambis’s approach was to identify some aspect of the virus that is unchanging. Pandemics
are invariably caused by A-strains of flu; B-strains, which are found only in humans, may cause epidemics but have never caused
The company identified a peptide, M2e, on the surface of all A-strains and developed a vaccine
that targeted it. When an individual is vaccinated the vaccine teaches the immune system to recognise and be alert to the
peptide so that as soon as flu arrives the body’s protective systems swing into action against it. To improve the vaccine’s
effectiveness, it was combined in the trial with adjuvants, chemicals that ginger up the immune system and improve its ability
to learn. The adjuvant called QS-21, made by Antigenics, proved to be the best. When this was added, 90 per cent of those
vaccinated had antibodies against the M2e peptide.
Michael Watson, the executive vice-president for research and development at Acambis, said:
“If there was an immediate threat of pandemic flu, it would be possible to complete
the trials and market the vaccine within three years. Without such a threat, it will likely take longer, perhaps five years.
“The beauty of the vaccine is its simplicity. It could be used in several different ways.
First, we could produce a pre-pandemic vaccine that we know would be effective against A-strains. If a bird flu strain such
as H5N1 turned into a pandemic strain we could get the vaccine out of storage and use it. Alternatively we could use it as
soon as we got the slightest inkling of a pandemic strain emerging. Or it could be used instead of the normal vaccine for
protecting against seasonal flu, with a vaccine against B-strains added. That would depend on how effective it was, which
we will only know after further trials.”
The fate of millions
— Flu viruses can drift and shift. Drift refers to the continual small changes that dictate
the annual reformulation of the flu vaccine to ensure that it works. Shift happens rarely and unpredictably, and produces
— There were three shifts in the 20th century, causing pandemics in 1918, 1957 and 1968.
Some virologists fear that another is overdue
— Pandemic strains strike human beings unprepared, and spread fast. The 1918 pandemic killed 20 million, some say 40 million
— Shifts occur when avian strains infect human beings, or avian and human strains share
genes, as may be happening in Asia
— Since the H5N1 avian strain first appeared in 2003, a few hundred cases have been transmitted to humans. About half of
those have died,
but this is not yet a pandemic strain, and may never become one