Today is bird flu's birthday

As far as the world is concerned, if any day can be said to be bird flu's birthday, it's today. The disease of birds doctors call influenza A subtype H5N1 may have had a long gestation period, but we're not sure how long. A form of the virus deadly to poultry was isolated from a goose in southern China (Guangdong province) in 1996, marking the first time the highly pathogenic form of the H5 bird virus poked its head above water for us to see. How long it had "been around" before that we don't know. Then in May, 1997, a three year old tot in Hong Kong came down with a flu-like illness that got worse and worse. He died a hard and painful death 12 days after onset. Tests showed it was an influenza A virus, but not the kind that usually infected humans (H1, H2 or H3). It was an unidentified subtype for human infection. Specimens were sent to the Netherlands and the US and in August the Dutch team identified it as the H5N1 subtype. It was designated A/Hong Kong/156/97 (H5N1) and shown to be closely related to isolate A/Chicken/Hong Kong/258/97 (H5N1) (see here for more on the naming system for flu viruses). The latter virus had been isolated from a chicken in Hong Kong in March, just months before the child fell ill. A poultry flu virus had jumped to humans.

But it was only a single case. Everyone hoped it was an isolated one and over the summer there were no others. But with the onset of flu season in November, additional cases did start to appear and by the end of December there were 17 more, of which 6 died. Including the index case, there were 18 cases with a 33% case fatality ratio. By then an emergency team from the US CDC had been in Hong Kong for three weeks and there was grave worry this might be the start of a pandemic with an especially lethal flu virus. On Sunday, December 28, 1997 the world was alerted:

Alarmed by the continuing spread of a deadly flu virus transmitted from birds to humans, Hong Kong health officials prepared today to slaughter the territory's entire population of farm-raised chickens and other poultry in markets and farms.

The extreme move, which follows a ban on chicken imports from China, was announced Sunday by Hong Kong Director of Health Margaret Chan after doctors confirmed at least 12 cases of the H5N1 virus, four of which were fatal. Nine other people, ranging widely in age, are suspected of having the virus, a particularly virulent type previously believed to infect only birds.

Health and agriculture officials said that more than 1,000 workers wearing masks and protective clothing will fan across the territory beginning this morning to gather an estimated 1.3 million chickens from 1,000 markets and 160 farms. The birds will be captured in sealed containers, asphyxiated, placed in plastic bags and buried in landfills.

"From tomorrow morning, we will start destroying all the chickens in Hong Kong Island, Kowloon and the New Territories," Secretary for Economic Services Stephen Ip told a news conference Sunday. Ip said the workers will also gather and kill ducks, geese, pigeons and quail housed near the chickens, in an operation that he said will be completed in 24 hours. (Rone Tempest, Los Angeles Times, print edition, page A1, Dec. 29, 1997)

This is the first of the mass poultry culls that have now become a fixture of the battle against bird flu. Because the number of outbreaks in poultry dropped in 2008 and the number of human cases dropped with them, some are saying the fight against bird flu is being won. But between 1997 and mid 2003 there was little evidence of H5N1. Then it burst out of Asia into Europe and Africa, infecting birds and humans on three continents. So far it is primarily a disease of birds, with only sporadic human cases. In fact the post 2003 virus seems less transmissible than the 1997 version.

Both facts should tell us something: we don't really know what this virus is going to do.

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Fascinating article. Perhaps those drastic measures taken in Hong Kong in 1997 did indeed halt the birth of a global pandemic. I have no doubt that if that same outbreak had happened anywhere else (Asia, Europe, Africa or America) the local governement would not have taken those same drastic steps and the pandemic would have burst out and would now be part of history.

Unfotunately it is obvious by the continued outbreaks around the world no countries measures (including HK in 97) have succeeded in wiping out the strain for good.

We need to keep pandemic preparedness at the forefront of every business manager's mind. It won't go away so better start preparing.

For free references, resources and to join their free pandemic preparedness email eCourse program, go to Bird Flu Manual Online or, if you need more comprehensive tutorials, tools and templates, consider Bird Flu D-I-Y eManual for your influenza pandemic preparedness.

The author is quite right and thank you for the post,

Sadly H5N1 continues to spread around the world like a bad weed or "Bad wolf" no one can stop. Viet Nam and several parts of India are under infection.

In seeing all that we have done for global warming, know we can do far more to prepare for a pandemic. At least our generation can see it comming.

The 9th US dept of health webcast is Jan 28th at 2pm ET at You can email your question before hand so please mark your calendars. The first 8 webcasts with DoE, DoD, DoT, Dept of Education are archived at the same website.

For more information, questions and answers or to post your thoughts go to or another pandemic blog. Just get going and not now wait only to find out others have not waited but acted.


Thank you for posting this informative article that gives a strong rationale for pandemic preparedness.

Part of influenza pandemic preparedness is a call NOT only to train a cadre of public health professionals in H5N1 containment; but also, to enlist a cadre of professionals from diverse disciplines such as business, political science, communications, environmental studies, to name a few. Giving the billions of dollars spent, number of poultry culled and, livelihoods lost in containment, it is often the poor who pay the price in pandemic preparedness.

To remedy some of the draconian measures taken in the name of pandemic preparedness, there is a need for broader public health interventions that are multidisciplinary and based on pro-poor initiatives such as equity and parity compensation for farmers, low or no cost vaccines and, affordable bio-security resources.

By Leslie Beale (not verified) on 29 Dec 2008 #permalink

An excellent posting but the comment that "... between 1997 and mid 2003 there was little evidence of H5N1 ..." requires further consideration and comment.

It is important to remember in this case as in so many others that "the absence of evidence IS NOT evidence of absence".

Analyses of the genetic diversity and genetic divergence of H5N1 virus strains have shown that H5N1 was circulating unreported in mainland China throughout this period.

By elephantman (not verified) on 29 Dec 2008 #permalink

elephantman: I didn't mean to imply it had disappeared. In fact I think it was seen in Hong Kong again in that period. But it had receded from view before its explosive spread in mid 2003. For all we know it was quite prevalent prior to 1997 as well. But I'm glad you stated it clearly in your comment.

Elephantman, "It is important to remember in this case as in so many others that 'the absence of evidence IS NOT evidence of absence'..."

Indeed, I agree to the nth degree! Well, Niman at Recombinomics points out there (((IS))) evidence of selective vision (Revere certainly appears to have never heard of Indonesia's Dewi Sartika or that antiviral drugs are losing their efficacy due to H1N1 influenza protein mutation (H274Y) -- implications for H5N1 over the longterm!?!).

Which is why, Revere's historical overview article should be read in conjunction with...

Recombinomics Commentary "Fifth Anniversary of H5N1" (December 29, 2008)

By Jonathon Singleton (not verified) on 29 Dec 2008 #permalink