- WASHINGTON (Reuters) - ``Bird flu'' that killed six people in Hong Kong
and prompted the slaughter of more than one million birds could happen
again any time, a U.S. expert warnedTuesday. But world health authorities
are well-prepared to fight flu and could move quickly to contain any outbreak,
said Nancy Cox, chief of the influenza branch at the Centers for Disease
Control and Prevention (CDC) in Atlanta.
- ``We have come to view this episode as
a dress rehearsal for the next pandemic of global influenza,'' Cox told
a news briefing sponsored by the National Foundation for Infectious Diseases.
- Authorities ordered the destruction of
1.4 million birds, mostly chickens, in Hong Kong after experts confirmed
a flu virus, known as H5N1, had jumped from poultry to people. Cox flew
to Hong Kong to study the outbreak and identified two separate strains
- She said that bird flu is a common infection
in poultry andspreads easily in modern intensive farms. Cox said flocks
around the world were infected with various types of bird flu and any of
them could cross to people. ``We know that influenza viruses of 15 different
sub-types exist in the avian reservoir worldwide and many of these viruses
haven't previously circulated in humans,'' she said.
- ``There is a potential for these viruses
to either jump directly to humans as with H5N1 or to move to another mammalian
species such as the pig and then move to humans.'' Experts believe that
is where most influenza strains originate -- first in birds, usually in
ducks, passing through pigs and then into humans.
- Cox said the cull was the right reaction
-- especially when it became clear that killing only sick chickens would
not be enough. ``The authorities in Hong Kong made a decision that may
have averted a worldwide epidemic,'' she said. But she noted it took six
months from the first case in Hong Kong last May until the second human
case in November. ``It should make us cautious about assuming that H5N1
is over,'' she said.
- The last confirmed case was Dec. 28,
just before the chicken cull started. The good news, Cox said, was that
world health authorities were prepared.
- ``The World Health Organization's global
influenza surveillance network did function successfully,'' she said. The
first human case of the virus was caught quickly and experts moved in immediately.
- They were able to make up tests for the
H5N1 strain and distribute them around the world to make sure that the
virus did not leave Hong Kong via an infected airline passenger. But there
was more that could be done. Cox said someone should develop a vaccine
against the H5 strain of flu in general and test it to see what doses might
be useful. Vaccinating all vulnerable people, especially the elderly, against
flu should also be a priority, she said. Flu epidemics have a tremendous
potential for killing people. The 1918 pandemic caused 25 million cases
in the United States alone and killed 500,000 people, many of them young,
healthy adults. ``Hospitals were overflowing,'' Cox said. A 1968 pandemic
of Hong Kong flu killed more than 46,000 people worldwide. Pandemics are
epidemics that spread over a large area. A bad flu season, such as the
one that just passed, could cause up to 200,000 cases and 40,000 deaths,