WILL THE HONG KONG "CHICKEN FLU" TRIGGER ANOTHER GLOBAL PANDEMIC?
BY CHARLES W. MOORE
Charles W. Moore 1998
A major news topic over Christmas and New Year's was the Hong Kong "Chicken Flu" outbreak.
While less than two dozen cases are known, and only four people have died at this
writing in early January, there is cause for concern. This story really began last May, when a three year old boy died in Hong Kong from complications of a flu caused
by the H5N1 virus--common in chickens but never before seen in humans. There was
a bird flu epidemic a month earlier in the region where the little boy lived.
In 1996, a conference of the world's leading epidemiologists warned that "The earth
might be attacked by a new type of world-wide epidemic influenza." Such an epidemic
is a certainty in the near future maintains Dr. Robert G. Webster, chairman of the
department of virology and molecular biology at St. Jude Children's Research Hospital
in Memphis, Tennessee, writing in the Journal of Infectious Diseases last August.
Could the Hong Kong Chicken flu be the one? At this point, human to human transmission
is thought to be "relatively inefficient," but influenza viruses mutate rapidly,
and this flu could very quickly become more infectious. International health authorities are scrambling to develop a vaccine, but it won't be available before next summer
at the earliest.
Most flu viruses originate in southeast Asia, where much of the population lives in
close contact with domestic fowl and pigs. The usual course of development is bird
flu viruses passing into pigs, where they mutate genetically and are passed on to
humans. "There's an enormous amount of influenza carried by birds," says Dr. Webster. "Live
bird markets that house a wide variety of [fowl] species... and occasionally pigs
together for sale directly to the public provide outstanding conditions for genetic
mixing and spreading of flu viruses."
However, in the case of the H5N1 virus, the pig intermediary step seems to have been
skipped. "A unique feature of this new virus... is that it managed to cross the avian-human
species barrier without prior adaptation in another mammalian species," said Dr. Webster in a press release. That level of mutagenic capacity is alarming. According
to Health Canada epidemiologist John Spika, once the virus is shown to be easily
transmissible from person to person, there is danger of a pandemic developing.
The first identifiable influenza epidemic was the 16th Century "English Sweat," probably
transported from the Orient by sailors. The 1918-1919 "Spanish flu" pandemic killed
an estimated 20 million to 40 million worldwide, including more than 500,000 North Americans. At one point, more than 10% of the U.S. workforce was bedridden. Of the
57,000 U.S. soldiers who died in World War I, 43,000 (85%) were killed by Spanish
influenza--not battle wounds. Entire Inuit villages in remote parts of northern Canada
and Alaska were wiped out by the virus. Even on the isolated south Pacific island of
Western Samoa, 20% of the population died of the Spanish flu over a few months. The
only country in the world to escape relatively lightly was Australia, thanks to strict
quarantine regulations.
It's not a question of "can it happen again?"--but rather "when," according to authorities.
A large proportion of the world's population today wasn't yet born during major epidemics
of Asian influenza H2N2 type-A virus in 1957-'58, and Hong Kong flu in 1968. ''You've got a very large, virgin population out there--" said Dr. Webster at
a St. Jude's press conference last Oct. 8, "large enough to start a pandemic."
Certain social innovations of our era provide ideal breeding grounds for flu epidemics.
According to microbiologist Charles P. Gerba of the University of Arizona, one of
North America's leading authorities on the transmission of disease by microbes, fifty percent of the toys in day care centres will typically be contaminated with viruses.
Studies show that the average small child touches his nose or mouth with his fingers
every three minutes, thus ingesting copious amounts of dirt and germs. Viruses can
survive on dry surfaces for up to 48 hours. People literally pick up infections all
the time by touching surfaces and then bringing fingers to their nose or mouth, says
Gerba. This is one of the reasons why infections spread so rapidly among children.
Can anything be done to prevent a 1918 style global pandemic, if not from the Hong
Kong chicken flu virus, then from another that' s sure to develop? "Predictions we've
been making, is that there will be another pandemic--probably before the end of the
century," says Robert Webster. "We've been preparing pandemic manuals, what to do when
the pandemic comes." Since 1993, there has been an informal, 14-member U.S. government
roundtable in Washington charged with planning for the next great pandemic.
If a pandemic starts, it is hoped that a vaccine will be ready in time for persons
at high risk--especially those under 40, invalids, and the elderly--to be immunized.
And if comes, common sense indicates that hand-washing, staying away from crowds,
and keeping fit will help avoid infection. However, the Australian experience in 1918-'19
suggests that strict quarantine of infected individuals would be the wisest course.
Germ-caused disease is a rapidly-growing public health problem. says Dr. Gerba. Microbial
illnesses are now the third leading cause of death in the U.S. In 1980 they were
in fifth place. "Sometime in the next century they will be on top," he predicts
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