Global flu plan needed to avert a pandemic

Michael Richardson, Singapore

What will happen if the deadly avian influenza virus that has decimated poultry flocks in China and Southeast Asia mutates so that it can pass quickly from person to person, triggering alarm bells that a dangerous new flu epidemic is about to start spreading around the world? This will be one of the top agenda items for the annual meeting this week of ministers and leaders of APEC, the Asia Pacific Economic Cooperation forum in Busan, South Korea.

For some time, the World Health Organization has been working on a plan to extinguish local outbreaks of the H5N1 virus among clusters of humans before the flu, which is normally highly infectious, can ignite a pandemic.

The prospect of halting a pandemic at its source or delaying its international spread is attractive. But it has never been tried before.The WHO still needs more time to finalize the intervention plan but hopes to do so by the end of this year.

In August, it was promised 3 million doses (amounting to 30 million capsules) of Tamiflu - one of two antiviral drugs considered most effective in reducing the severity of illness in people caused by H5N1, which until now has been largely been confined to birds.

This stockpile is the basis of the WHO's plan. Tamiflu's maker, Swiss-based Roche Holdings AG, has promised that the first one million doses will be ready early next year, and the remaining two million before mid-2006.

The WHO has also held preliminary discussions with Roche and potential donor governments to establish a separate stockpile of antiviral drugs in Asia for possible emergency use. The aim is to get richer states to donate, in cash or kind, the equivalent of 5 percent of their own Tamiflu stockpiles. Thailand -- which along with Singapore is one of the few Southeast Asian nations to have ordered Tamiflu -- has offered to donate 5 percent of its 750,000 treatments to a Southeast Asian stockpile.

Since bird flu became endemic in East Asia in 2003, Australia has committed $AUD41 million to improve regional detection and response capabilities. It has provided Indonesia with bird flu assistance worth $AUD15.5 million, including 50,000 Tamiflu courses.

The WHO move to create a stockpile for East Asia comes amid increasing concern that almost all of the 50 countries that have placed orders for Tamiflu are in the developed and newly industrialized world. This leaves developing nations exposed, including China and many in Southeast Asia that are considered most likely to be the epicenters of any new human flu pandemic.

Epidemiologists say that the world is in a race against time to prepare for a pandemic, although no one knows when it will start. There have been three flu pandemics in the last century. The most recent was in 1968. The worst was in 1918 and is thought to have been caused by an avian-like virus. An estimated 40 - 50 million people died.

Vaccines offer the best protection against flu. But they must be tailor made to match any new strain of influenza when it emerges and infects humans. This can take up to six months.

A number of governments and pharmaceutical companies are now giving top priority to research and processes that will shorten the time needed to mass produce flu vaccines. The results of this work must be shared so that breakthroughs can be rapidly harnessed. If everyone on earth is to be protected, about 6.5 billion doses of vaccine would have to be produced and administered. This is a huge challenge.

Meanwhile, the absence of an effective vaccine to protect vulnerable populations creates a gaping hole in global pandemic defenses. Neither of the two available anti-viral drugs, Tamiflu and Relenza, prevent or cure infection by an H5N1-like pathogen, although they may help reduce the severity of illness if taken within 48 hours after symptoms begin.

The best hope of containing any pandemic virus outbreak among humans may therefore be to place stockpiles of anti-viral medicines in the hands of the WHO and the national governments of countries it considers are particularly vulnerable. The aim would be to rush the drugs to any area of the world where a cluster of human-to-human cases is detected in the hope that it can be isolated and quenched until a safe vaccine can be mass-produced, distributed and administered.

The WHO says that for intervention to be successful, at least five conditions will have to be met. The first viruses that can jump from human to human will not yet be highly contagious and will be limited to a small geographical area. The first clusters of human flu cases will be rapidly detected and reported. Antiviral drugs from the stockpile will be quickly administered to all of the affected population. And movement of people in and out of the areas will be effectively restricted.

Given the unpredictable nature of influenza viruses, it is impossible to know in advance if the first two conditions will apply. And the remaining conditions will depend heavily on the willingness and ability of both national and local authorities in the country concerned to cooperate with the WHO.

The writer is a visiting senior research fellow at the Institute of South-East Asian Studies in Singapore. He is the author of Bird Flu & Bio-Security: Is the World a Dead Duck, a new report posted on the ISEAS website: www.iseas.edu.sg click on Viewpoints.