Sunday 3 May 2009

H1N1 Flu is resistant to Tamilflu

"According to the CDC, in the flu season of 2007-8 only 12% of
circulating H1 flu viruses were resistant to Tamiflu. This season 98%
of them are, for reasons not yet understood. "

At least 98% of them, but so far no resistance shown by the current
Swine Flu.

The seasonal flu is also called H1N1 but it originates from PIgs. It
killed millions every year but only to the most vulnerable. They
control it using vaccines but not by controlling the originator of
this virus, i.e. PIGS.

Malaysia must stock Relenza as well because H1N1 flu does not have
immunity against it yet.

From The Sunday Times
May 3, 2009
Mutant fears over 'mild flu'
Experts say swine flu appears less virulent than the typical seasonal
virus, but are still concerned about its future path
market - swine flu

Local residents wearing face masks shop at the Central de Abastos
market, one of the biggest in Mexico City
Steven Swinford and Tony Allen-Mills in Mexico City

The meeting was only short, but it was enough to give Barry Greatorex
a dose of swine flu. Ten days ago the 43-year-old project manager for
a freight company travelled to Castle Donington in Leicestershire to
see a colleague who had returned from a holiday in Mexico.

"I was just in her office and was probably only there for half an hour
or so having a conversation with her," Greatorex said yesterday from
his home in Chipping Sodbury, Gloucesterhire. "In that period of time
I seemed to have contracted it. She had a cough and that's seemingly
where I got it."

Last Monday the symptoms began. "The first two or three days were
pretty horrible," he said. "Each day was worse, starting with chest
pains and then the fever."

Eventually he was put on antiviral drugs and the pain eased. "I have a
runny nose now and a bit of a cough, but I'm feeling a lot better," he
said.
Related Links

* Swine flu – schoolgirl among new British cases

* Ryanair boss - only 'slumdwellers' at risk

* LIVE: latest news on swine flu

Greatorex's experience was being repeated across Britain as the virus
spread with alarming speed. Children at a primary school in Paignton,
Devon, were in tears after it was confirmed that a 12-year-old girl
had contracted swine flu.

Yesterday morning Graham Young, an oil-rig worker, was flown to
Aberdeen from the North Sea after concerns that he had been exposed to
the virus. Last weekend he was drinking with his friend, Graeme
Pacitti, 24, the first victim of human-to-human transmission of swine
flu within the UK. Pacitti is thought to have contracted the virus
from Iain Askham, the Falkirk man who, with his bride, Dawn, became
the first confirmed UK case after honeymooning in Mexico.

By the end of the week 15 cases of swine flu had been confirmed in
Britain, as far apart as Merseyside, Tyneside, London and Bristol.
This weekend more than 600 samples were being tested for the virus.

As the week progressed, experts issued a procession of dire warnings.
Some compared the virus with Spanish flu, which killed an estimated
50m people worldwide in 1918-19. Both viruses are of the same strain
and are mainly affecting people aged between 25 and 45.

Professor Neil Ferguson, an epidemiologist at Imperial College,
London, warned that up to 40% of the population could become ill in
this outbreak.

Robert Madelin, the European commission's most senior health official,
said: "The question now is not whether people will die, but whether it
will be thousands, tens of thousands or hundreds of thousands."

The warnings reached fever pitch on Wednesday when Margaret Chan,
director-general of the World Health Organisation (WHO), raised the
global alert from phase four to phase five, one below the maximum.
This meant that a pandemic, in which a disease spreads rapidly from
continent to continent, was imminent. "It really is all of humanity
that is under threat," she said.

This week the Department of Health will post leaflets to every
household urging people to find "flu friends" who can bring them
groceries and supplies if they fall ill. It will also dispatch bundles
of antiviral drugs to hospitals and clinics.

Yet despite the preparations and warnings, the number of deaths
remains small. To date, 17 countries have confirmed more than 700
cases of H1N1, although the figures are rising constantly, with just
17 deaths having been directly attributed to it. All bar one were in
Mexico, where the virus is believed to have originated. The exception
was a two-year-old Mexican boy who died on a visit to Texas.

In the UK, swine flu is producing mild symptoms, almost identical to
those associated with seasonal flu. The virus is also responding well
to treatment from the antiviral drug Tamiflu.

At Newcastle University, where a new case was discovered on Thursday,
Ellis Hanson, a 20-year-old fine arts student, said she and her
friends were not concerned because they remembered previous scares
about bird flu and Sars. "We have exams coming up and people are
worrying more about them," she said.

Is her sang-froid justified? Just how severe will a potential flu
pandemic be? Why is it killing only people in or from Mexico? And why
are scientists and the WHO so concerned?

AT THE Azcapotzalco farmers' market in Mexico City, Esmeralda Salazar
was hunting for protection from swine flu. She brushed past the stalls
laden with fresh fruit and vegetables and stopped at a small stand
advertising "medicinal plants . . . spiritual waters . . . natural
lotions . . . amulets".

Behind a table piled high with strange-looking herbs, tangled weeds
and strips of bark, an elderly man who said his name was Christian
produced a small plastic bag stuffed with what seemed to be tea leaves
and twigs.

The concoction smelled vaguely of peppermint and, according to
Christian, would "build up your defences against the virus". The woman
handed over 10 pesos (about 45p).

Thousands of Mexicans took a conventional approach to the swine flu
threat, and queued for hours last week to see doctors at hospitals and
clinics. Yet Salazar's preference for alternative medicines reflected
a popular Mexican tradition that officials believe almost certainly
contributed to a dangerous delay in the initial diagnosis of swine
flu.

"When Mexicans fall ill, they first try to cure themselves," said
Edmundo Bermudez as he queued at a nearby chemist. "It's easy to get
drugs here without a prescription, so you just go to the chemist and
say, 'I'm not feeling well, give me some penicillin'.

"Everyone here thinks penicillin cures everything. But go to a doctor?
That's expensive, and then he sends you to hospital and you have to
wait all day. For many of us that means missing work and losing pay."

A lingering enthusiasm for traditional herbal medicines remains potent
even in sophisticated cities. In rural areas they are often the norm.

"People wait too long to go to doctors," agreed Marcelo Noguera,
undersecretary of health for the state of Oaxaca, where the first
fatality in the outbreak was recorded.

The high fatality rate among Mexican victims – compared with the much
less severe effects of the virus in other countries – was being blamed
largely on initial delays in seeking treatment and on possible
complications from misdiagnosis and inappropriate medicine.

Some of these factors appear to have been present in the death of
Adela Maria Gutierrez, who fell ill at the beginning of April. She
treated herself with aspirin and waited three days to see a doctor who
then gave her antibiotics for a sore throat.

She was reluctant to leave work to go to hospital – where, it later
turned out, there were Easter-related staff shortages and no available
respirator. By the time specialists realised she might have a rare
form of flu, it was too late to save her.

One senior Mexican epidemiologist last week blamed "the idiosyncrasies
of Mexicans" for a shared suspicion of hospitals or anything run by
the government; less easy to explain was why Gutierrez died while many
people who came into contact with her – including her husband Luis –
have displayed no symptoms of the virus.

Even in the country worst hit by the flu, opinion polls last week
indicated high levels of public scepticism about the government's
handling of the crisis – notably its confused and contradictory
announcements about the numbers of people infected.

On Friday health officials said that of 908 samples from apparent
victims tested in the latest batch sent to America for assessment,
only 397 came back positive, suggesting that the overall numbers may
be below the 2,500 suspected. Yesterday the Mexican government revised
the number of suspected swine flu deaths in the country from 176 to
101.

The capital's hospitals and clinics were also strangely quiet for the
supposed centre of a global flu pandemic. On Friday at the city's
biggest hospital, only a handful of relatives waited anxiously for
family members who were feeling unwell. "It's very quiet," said a
nurse at the gate. "We are seeing no more people than usual."

Left-wing critics of President Felipe Calderon's government were quick
to suggest that the authorities had deliberately inflated the threat
of a pandemic to take credit for resolving a much milder crisis. Part
of his prescription was an enforced five-day public holiday that
started on Friday.

"They have been sowing a climate of fear and psychosis," claimed a
trade union leader who addressed fewer than 100 communist faithful in
a brief May Day rally at the capital's main square, the Zocalo.

Ricardo Monreal, a leftist senator, said of the government's virus
data: "These are overly conservative numbers and they seem to be
hiding something." MODERN diagnostic techniques and the internet,
however, guaranteed that the secrets of the virus could not be hidden.
The first reports of a novel flu emanating from Mexico sparked a
worldwide race to unpick the virus.

Last weekend the Centers for Disease Control (CDC) in Atlanta
published the DNA sequences of several virus samples in an online
public library. Since then more than 30 swine flu samples have been
made available by scientists.

These virtual viruses are being pored over by hundreds of scientists
as they search for clues about swine flu's origins, its
infectiousness, virulence and susceptibility to antiviral drugs.
Despite the WHO's gloomy prognosis, initial analysis suggests the
virus may not be as lethal as first thought.

In the US scientists have found that the virus differs significantly
from the strain that brought such carnage in 1918, lacking an amino
acid that increases the number of virus particles in the lungs and
makes the disease more deadly.

"There are certain characteristics, molecular signatures, which this
virus lacks," said Peter Palese, a microbiologist and influenza expert
at Mount Sinai medical centre in New York.

In many cases, previous exposure to other viruses may also be giving
people a level of natural immunity.

Ralph Tripp, an influenza expert at the University of Georgia, has
compared the virus with the 1957 flu pandemic strain, which killed up
to 2m people worldwide. His early analysis of the protein-making
structure suggests they are similar. As a result, exposure to the
earlier pandemic may be giving the elderly a higher level of immunity,
as seems to be the case in Mexico where the disease has mostly killed
young adults.

According to Wendy Barclay, chairwoman of influenza virology at
Imperial College, London, the swine flu looks like a mild strain. It
is an H1N1 virus, the same type as seasonal flu which circulates
around the world every year and kills about 0.1% of those infected.

The virus tends to attach to receptors on cells in the upper
respiratory tract, the nose and the throat, causing mild illness but
spreading easily through coughs and sneezes. By contrast bird flu,
H5N1, attaches deep in the lungs and causes severe illness.

Professor Alan Hay, director of the WHO's World Influenza Centre in
Mill Hill, north London, is encouraged by the similarities. His team
is analysing a live sample of the virus and assessing whether people
may already have a level of natural immunity.

If so, swine flu may ultimately prove no more deadly than seasonal
flu, which nevertheless kills up to 12,000 people a year in the UK and
up to 1m worldwide.

Hay said: "The viruses are related. That means there is a chance that
we have natural immunity. The difficulty is that people have been
primed with the bird flu horror stories about pandemics, which was a
pretty horrendous scenario.

"This might not be any more virulent than normal seasonal flu
infections. We feel reassured that if this develops into a pandemic it
might not be a particularly severe one."

Some scientists are consequently becoming increasingly concerned by
the levels of hype and fear surrounding the virus.

Tripp warned that the WHO is failing to keep the risk in perspective,
especially after Chan's comment that "all humanity is under threat".

"They should just tell the facts and not extrapolate anything," he
said. "[The statement] is clearly her opinion – it's completely
comment, not impartial fact."

Frank Furedi, professor of sociology at the University of Kent, said:
"They [the WHO and other researchers] have adopted this language where
they continually assume the worst case scenario. It means we lose the
ability to make balanced assessments of risk.

"It is like the boy who cried wolf – if we react with this level of
hysteria now, what will we do when a really bad pandemic comes along?"
SO are the warnings and preparations by governments out of kilter?

Even though the virus is relatively mild, it is highly contagious,
meaning it has the potential to infect so many people that a large
number could die.

Nikki Shindo, a medical officer at the WHO, said: "Even though the
fatality rate is relatively low we will see a lot of people dying
because of the large number of people being infected. As more and more
cases are reported in the US, we are starting to see some
hospitalisations and more severe cases. We may see the same pattern in
the UK."

The lingering fear is that the virus will mutate into a more lethal
form. Barclay said: "We need to watch out for whether this virus will
change. Often viruses that have jumped species and found new hosts are
under considerable pressure to adapt."

The WHO is also concerned that the virus will develop a resistance to
Tamiflu, the world's drug of choice in the fight against a pandemic
flu outbreak. There are already ominous signs.

According to the CDC, in the flu season of 2007-8 only 12% of
circulating H1 flu viruses were resistant to Tamiflu. This season 98%
of them are, for reasons not yet understood.

The prospect of swine flu developing a spontaneous resistance to
Tamiflu, or swapping genes with an existing resistant H1N1 strain, is
alarming officials at the WHO. "It is a big concern," said Shindo.

There is another treatment option, however. The UK has stockpiled 12m
doses of Relenza, an antiviral that has also proved effective at
treating swine flu. H1 viruses have no resistance to it.

The government has stockpiled twice as much Tamiflu, however, and last
week it ordered 15m more doses, making the ratio of Tamiflu to Relenza
almost four to one.

Hugh Pennington, emeritus professor of bacteriology at Aberdeen
University, said stocks of Relenza in Britain should be increased.

"We have to get as much as possible because we don't know how
effective Tamiflu will be," he said. "There is an issue of Tamiflu
resistance. All things being equal, it would be nice to get as much
Relenza as we can get our hands on. No one really knows if Tamiflu
will significantly reduce transmission; the expectation is it will,
but we don't know for sure."

The only long-term solution to a pandemic would be to develop a
vaccine.

At present four laboratories worldwide, including the National
Institute for Biological Standards and Control in north London, are
working with the live virus to find one.

The scientists will take the genes that make swine flu's outer coating
and attach them to a harmless human virus called PR8. This
reconstructed virus is safe for humans, but triggers an immune
response that specifically protects against the swine flu strain.

The process, however, is slow. Scientists estimate that it will take
three weeks to make a seed vaccine, then a further four to six months
to grow enough for mass distribution.

It is also not without controversy. To accommodate the mass production
of a pandemic flu vaccine drug, manufacturers will have to scale back
production of the annual winter flu jab for the elderly and other
vulnerable groups.

Ministers admitted last week that there would be a significant "public
health difficulty" if the WHO ordered companies to switch production.

Eric Althoff, a spokesman for Novartis, the Swiss pharmaceutical
company that is one of the world's biggest vaccine manufacturers,
said: "The WHO will be trying to balance the benefits of producing a
pandemic flu vaccine against the risks of halting production of
seasonal flu vaccine. It is a difficult choice." THIS weekend the WHO
was preparing to declare a full-blown pandemic. According to its
experts the swine flu alert is likely to be raised from phase five to
six in a matter of days, despite its being a relatively mild strain.
The move will leave the government continuing to tread a fine line
between raising public awareness and avoiding scare tactics.

Sir Liam Donaldson, the chief medical officer, has to date been
notably restrained, refraining from discussing the number of people
who could be killed and from the alarmist language of the WHO.

Many in the forefront of treating the virus fear the line has already
been crossed, with the public mistrusting what they have heard from
official sources.

One doctor who treated a swine flu sufferer last week said: "The
patient was terrified when he got it. It's really been talked up. This
time last week we were all incredibly worried because the reports
coming out were that hospitals were full and people were dying all
over the place.

"We have this awareness of the 1918 epidemic which had a very, very
high mortality rate. But actually we are getting much more relieved
that it doesn't seem to be severe. In terms of severity the symptoms
are unpleasant – fevers, shivering, aches – but not severe. Our
patient made a full recovery.

"The way they [the WHO] are talking you would think our culture is
collapsing."

Additional reporting: Ronald Buchanan

Dealing with the dread factor

As a species, we are poor at assessing risk, writes Hugh Aldersey-
Williams. Evolution has equipped us well to deal with immediate danger
– our senses alert us when we prepare to cross the road or taste
unfamiliar food – but we have no way of measuring dangers further off:
that is to say, risks.

We find it easy to imagine risks but impossible to assess them. As I
write, I have no practical idea what's the greatest risk I face. A
virus might fly in through the window, a plane might crash on the
roof.

More likely, perhaps, a rat might chew through the wiring and start a
fire. But I can't make the assessment.

Statistics don't really help. They appear to us as cold, abstract
numbers. There's no way to relate them to the visceral horrors we
create in our mind's eye.

Even if I could get hold of a figure for the likelihood of a rat-
induced fire, I couldn't be sure it was valid for my circumstances and
I still wouldn't have a basis for comparing it against all the other
hazards I face.

As a result, we underestimate the risk where the context seems benign,
such as that from x-rays, and overestimate it where there is a high
dread factor – in the cases of, say, nuclear power, terrorism or knife
crime.

Sigmund Freud gave three core reasons for human anxiety. The first two
are our failing bodies and nature's might, which cover our fear of
disease and disaster. The third agent of worry is social aggravation:
we can talk ourselves into a state of fear.

Our response to risk is negotiated over the dinner table and by the
water cooler. Worried about the economy, migrant workers taking your
job, or your children's school? Well, then, talk about it. It's how we
decide what to worry about.

That is why there has been little panic about the spread of swine flu.
The national conversation recalls the bird flu scare of 2005-6.
Alarming government figures were published suggesting that a quarter
of Britain's population would be infected and that 1 in 100 might die.
The outbreak never came.

A rational response then was to observe that while probably nobody
would die of bird flu in Britain, the usual 12,000 people a year were
pretty sure to die of ordinary flu, a disease too chronically boring
to write headlines about. This time the virus is a type of ordinary
flu. That is why planning, and not panicking, seems to be the order of
the day.

Hugh Aldersey-Williams is the co-author with Simon Briscoe of
Panicology (Penguin)

Is this the bird flu scare revisited?

Why all the fuss? Influenza is a virus that constantly changes, some
versions being mild, others lethal. The current outbreak of swine flu
is causing concern because many of the 101 people believed to have
been killed by it in Mexico have been young and middle-aged, rather
than the elderly and infirm, the usual victims of flu.

But hasn't only one person outside Mexico died? Yes, and that victim
was a child in the US who had come from Mexico. The disease may indeed
be a mild form of flu, but it's too early to tell for sure. What is
clear is that it has spread worldwide and that it can transfer not
just from pigs to humans, but from human to human.

Why is this called a "pandemic" when ordinary flu is not? Flu viruses
circulate all the time, usually causing epidemics in winter in
temperate countries. A pandemic occurs, according to the World Health
Organisation (WHO), when a new flu virus appears against which humans
have no immunity, resulting in outbreaks worldwide. The swine flu
virus, even though it has yet to kill large numbers – and may never do
– meets this criterion.

Why does everyone mention 1918? The "Spanish flu" of 1918-19 was the
worst pandemic in modern history. A new flu strain emerged that,
unusually, was most deadly for those aged between 20 and 40. Many are
thought to have suffered "cytokine storms" – massive overreactions of
the immune systems. An estimated 50m people worldwide died. Remember,
however, that mortality rates may have been high because living
conditions and medical treatments in 1918 were nowhere near as
advanced as they are in many countries today.

If we're not at that point, why is the WHO saying "all humanity" is at
risk? There hasn't been a significant pandemic for decades; younger
generations may have low immunity; modern travel spreads disease
faster than ever. All these factors mean a virulent new virus could
circle the globe very rapidly.

How does the virus spread? Mainly through tiny airborne droplets from
the coughs and sneezes of infected people. Carriers can become
infectious a day before they show symptoms of flu. The virus can also
survive for several hours on an inanimate surface, such as a door
handle. If you pick up the virus on your hands and then touch your
mouth, nose or eyes, it can still infect you.

So what can I do to protect myself? Avoid people who have the flu and
are coughing and sneezing, and wash your hands frequently.

What about a face mask? They are better than nothing if you cannot
avoid infected people – but they are not designed to stop flu
infection and you may still inhale the virus even if you are wearing
one.

What should I do if I get symptoms? Consult the NHS website, which has
a "symptom checker", for advice or ring the government's advice line
on 0800 1 513 513. If your symptoms are confirmed, ring your GP or NHS
Direct. Do not go to your doctor in person.

Can medicine save me? Swine flu H1N1 is at present treatable with a
drug called Tamiflu, which the government has stockpiled. However, as
flu viruses mutate they can develop resistance to drugs. Scientists
may also develop a vaccine against swine flu, though this will take
months. Remember: even in the 1918 pandemic only a tiny fraction of
those infected died. Most people recover naturally.

Is this a rerun of the bird flu and Sars panics that came to nothing?
Possibly, though it's too early to say. But with flu pandemics,
officials err on the side of caution.

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