H5N1 influenza and the implications for Europe

Coulombier D & Ekdahl K tell us that, although it is hard to
assess precisely the risk of a pandemic, a pandemic will occur in the
future. They say that Europe is very vulnerable and, if a quarter or more
of the population are affected, then vital functions, such as food and
fuel, will be severely threatened [1].

They make a one-sentence reference to the SARS epidemic of 2003.

They tell us that Europe produces more influenza vaccine than any
other continent, but that there will be a shortage of vaccine in a
pandemic. We are told that anti-virals would play some part in prevention
because they are effective in the early treatment of influenza.

Coulombier & Ekdahl tell the ordinary person, all too briefly,
what they can do under "non-medical interventions", such as improved
personal hygiene, individuals isolating themselves early on and the
cancellation of mass events.

In the whole of their article, there is absolutely no mention of the
use of face masks, even under their vague "improved personal hygiene".

The UK's Chief Medical Officer writes to all doctors in England a
short article entitled "Preparing for Pandemic Influenza" Nowhere in the
nation's preparation are face masks mentioned![2]

This silence about face-masks is astonishing! It is astonishing in
the light of the published experience of the SARS epidemic.

The Lancet published the results of a survey of hospital staff
exposed to 11 SARS patients over a two week period [3]. None of the 69
staff who had used either a surgical mask or the N95 mask and who had
taken the other measures used by all staff, contracted the virus.

Of the 13 staff, who did become infected, none of them used anything
more than a paper mask, even though they had washed their hands and done
all the "improved personal hygiene" referred to by Coulombier &
Ekdahl.

The chief microbiologist in this study from Hong Kong, Professor WH
Seto, concluded that wearing a surgical or N95 mask can give a person,
dealing with SARS patients in hospital, up to 13 times more protection
than not wearing one [3].

Seto told New Scientist that "masks seem essential for protection"
[4].

Whilst members of the public would have difficulty in obtaining
surgical masks during a pandemic, they can purchase the N95 masks before
the pandemic starts. They cost about £2 each.

Why would anyone want to have an N95 mask in the house?

Firstly, they are effective in protecting against influenza viruses
as shown in the SARS epidemic, where those people working in a virus super
-charged atomosphere did not get infected if they were wearing an N95 or
equivalent surgical mask.

Seto says that masks, designed to block airborne particles, will
protect the face from droplets coughed out by infected people. His survey
findings fit well with droplet transmission, which is generated at face
level.

Someone may say that the N95 mask will only filter out particles
larger than 0.3 microns (300 nanometres) and that viruses are much smaller
than this. The SARS virus ranges in size between 80-160 nanometres.

However, the viruses will be clumped together in sputem and phlegm,
and covered in mucus and water.

Secondly, there will not be enough anti-virals for everyone.

Thirdly, there will be a dangerous delay before the vaccine becomes
available in bulk.

Fourthly, it is something which the helpless man, woman and child can
do to protect themselves effectively. And that does make you feel much
better!

So why do Coulombier & Ekdahl, of the prestigious Europe Centre
for Disease Prevention & Control, not even mention face-masks?

Why does the Chief Medical Officer in England fail to tell doctors
about the benefits of face-masks for their patients and, indeed, for
themselves?

Perhaps the reasoning goes that this is a medical problem and must be
left to the experts supplying anti-virals and vaccines, because there is
nothing that the simple public can do.

It is fascinating how published information, such as the protective
benefits of face-masks in the SARS epidemic, can be rendered pointless in
the hour of greatest need. So what is the point of publishing medical
information?

When a "John Snow pump handle" solution is there from reading an
article in the Lancet, what is the point of medical publishing if tens of
thousands are killed by the virus and tens of thousands are left damaged?

When the broadcast recommendation to use an N95 mask could have been
given, and thousands upon thousands of personal, national and business
economies saved, all from the reading of an article in the Lancet, what is
the point of medical publishing?

References:

1. H5N1 Influenza and the Implications for Europe, Coulombier D &
Ekdahl K, BMJ 2005; 331: 413-414 (20 August).

2. Preparing for Pandemic Influenza, CMO Update, Issue 42, p1-2, Summer
2005.

3. The Lancet Vol 361, p 1520, 203.

4. Face Masks are Best Protection Against SARS, New Scientist 15 March
2005 www.newscientist.com?article.ns?id=dn3692.

Competing interests:
None declared