- Hello, Jeff - I would not even post this
one. FYI, The theory is presented below that vaccine is a panacea. It
is NOT. And what, pray tell, is a 'pre-pandemic' vaccine?
- The current prepandemic vaccine (whatever
that is) will NOT protect against a newly-emerged pandemic strain or strains
of H5. It would probably take a minimum of ONE year before a vaccine using
a new strain could even be developed, and such a vaccine would probably
not have the efficacy desired. In short, forget vaccines. The best defense
is to NOT get infected.
- Pandemic Risk Remains
- By Adam Beaumont
- Human flu viruses prefer to infect cells
in areas like the nose and windpipe, thereby increasing the risk of transmission.
But the Federal Health Office warns that this behaviour could change if
the H5N1 virus mutates.
- Patrick Mathys, an epidemiologist at
the health office, told swissinfo that the findings offered a possible
explanation for the small number of human cases over the past couple of
- "This means that the virus load
when you sneeze or cough is obviously too small to infect people,"
- "This is not bad news at all but
you cannot say we are safe now. We still think H5N1 has the potential to
mutate into a pandemic strain."
- The H5N1 virus has killed more than 100
people and infected over 180 worldwide since it re-emerged in late 2003.
- People infected with the virus have virtually
all been in close contact with diseased birds but scientists fear it could
mutate into a highly infectious pandemic strain that could kill millions.
- So far avian flu has been found in 24
wild birds in Switzerland but there have been no human cases.
- New developments
- The discovery, published in the journal
Nature on Thursday, comes just days after another more worrying development
earlier in the week.
- On Monday researchers from the US Centers
for Disease Control and Prevention said the H5N1 virus had evolved into
two separate strains.
- The health office described the announcement
as "bad news" for the development of a vaccine.
- The Swiss government has placed an order
with France's Sanofi Pasteur for 100,000 doses of a pre-pandemic vaccine
against H5N1. The intention is to distribute these to frontline workers
dealing with infected birds.
- "As soon as you have two strains
you probably have to develop two strains of a vaccine as well, and this
could make it more difficult to have a vaccine ready against H5N1,"
- Infectious diseases
- Christian Ruef, associate head of infectious
diseases at Zurich University Hospital, told swissinfo that it was to be
expected that the virus would evolve.
- "That's what happens with normal
flu strains. They are quite unstable and we get mutations throughout the
year, and over the years we get small shifts. For example, the vaccine
we use for normal human flu does not completely or optimally cover strains
that are circulating now," he said.
- Ruef said that when a pandemic arrived
one strain of bird flu was likely to prove dominant and drugmakers would
direct a vaccine against this virus.
- Mathys added that the Sanofi vaccine
was still going through clinical trails and was unlikely to be ready until
later this year.
- But he said that if bird flu was to spread
among Swiss poultry flocks before the drug had been cleared, the government
might decide to use it anyway.
- "If the situation worsens and we
have mass outbreaks in poultry in Switzerland and we have to protect the
personnel culling poultry then we will probably buy the vaccine at a stage
when not all clinical trials have passed," he said.
- "If some clinical trials are missing
it's really difficult to say whether the vaccine is 100 per cent safe or
whether it works. You can probably say it's safe based on what we've seen
so far but whether it protects you very well against the circulating H5N1,
you can't say."
- Patricia A. Doyle, DVM, PhD
- Bus Admin, Tropical Agricultural Economics
- Univ of West Indies
- Please visit my "Emerging Diseases"
message board at:
- Also my new website:
- Zhan le Devlesa tai sastimasa
- Go with God and in Good Health