The WHO Says It Could Take Them Years
To Lower The Pandemic Alert Level
It could take years for the World Health Organisation to downgrade
the H1N1 flu from a pandemic to seasonal-like virus, the U.N. agency
said on Friday.
The WHO moved its six-point pandemic alert level to the top rung
in June in response to the spread of the new virus widely known
as swine flu, which has killed at least 4,500 people, especially
in North America.
WHO spokesman Gregory Hartl said that health warning would stay
in place until people can better fend off infection from the H1N1
strain.
"At some point in the future, there would be a recognition
of the fact that if it's no longer circulating on a sustainable
basis in communities. Then you would lower the pandemic level,"
he said, while stressing: "There is absolutely no indication
yet of that happening."
In previous pandemics, Hartl said, it has taken time for worrisome
flu strains to become less contagious. The slowdown generally
comes from people having some prior exposure to the virus or gaining
protection from a vaccine.
"Eventually a pandemic virus becomes more like a seasonal
virus and that normally will take something like two to three
years," Hartl said. "Once enough people either have
been vaccinated or have contracted the virus, then it becomes
more difficult to spread. It starts acting like a seasonal flu."
National health authorities conduct regular monitoring of flu
viruses and research on the circulating strains is used by pharmaceutical
companies who sell seasonal flu shots, which normally contain
a mixture of a few viruses.
GlaxoSmithKline,
Novartis,
Baxter,
AstraZeneca
and CSL
are among the firms now scrambling to develop and sell H1N1 flu
shots, yielding them billions of dollars in government orders.
China began the world's first mass vaccination programme in late
September and Australia and the United States have also launched
campaigns targeting children and health workers first.
Hartl said there was no sign yet that the pandemic strain had
mutated into a more dangerous or more mild form than the one first
identified in Mexico and the United States.
"So far the virus has remained quite homogenous," he
said.
In its latest snapshot of the spreading virus, also released
on Friday, the WHO said there has been an unusually early start
of flu-like illness in the northern hemisphere this autumn.
Influenza viruses thrive in colder climates and normally pack
the biggest punch in winter.
In recent weeks some countries in Europe seen higher than normal
respiratory disease activity and Japan's flu pattern is above
its, especially in big cities. The United States, Mexico and Canada
have also had higher than normal illness rates for the time of
year, the WHO said in the statement.
Flu transmission has stayed steady in tropical parts of the Americas
and Asia, with "high intensity respiratory diseases activity"
reported in Colombia, Cuba and El Salvador.
But in the southern hemisphere, flu infections have waned with
the end of the winter season, the WHO said, describing subsided
transmission in Chile, Argentina and New Zealand and falling rates
of illness in South Africa and Australia.
* A
full list of h1n1 vaccine ingredients, alerts and warnings.
Reference Sources 89
October 12, 2009
...............................................................................................................
|