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Vietnam last on flu vaccine list (2004)
by Debora MacKenzie Monday, Sep. 19, 2005 at 4:08 PM mail:

Vietnam last on flu vaccine list

* 19:00 21 January 2004
* Exclusive from New Scientist Print Edition
* Debora MacKenzie


Drug company contracts and intellectual property rights are impeding efforts to ensure an outbreak of bird flu in Vietnam does not result in a deadly human pandemic.

All the victims so far got the disease from poultry, but the big fear is that the virus could turn into a form capable of spreading from person to person. A flu vaccine that might help prevent this will soon become available, but instead of going to Vietnam it will be sent to rich countries to fulfil existing contracts.

And researchers who have created vaccines that might save us if the bird flu does start spreading between people are unsure how to proceed without falling foul of patent rights.

Doctors have been warning for years that another flu pandemic as deadly as the 1918 one is inevitable, and many worry it could be about to happen. After an outbreak of the H5N1 strain of bird flu in poultry, Vietnam has reported 18 suspected human cases, 15 of whom have died. The World Health Organization has so far confirmed that five of the cases were caused by the H5N1 strain. Unlike previous H5N1 outbreaks, the victims are mostly children.

So far there is no sign of the bird virus spreading between people. But if someone is infected by H5N1 and a normal human flu virus at the same time, the viruses could recombine.

This might give rise to a new virus able to spread among people as easily as human flu but far more deadly, partly because it would bear the bird flu's H5 and N1 surface proteins, which human immune systems have not been primed to recognise.


Fujian strain

To prevent this, the WHO wants to give the normal flu vaccine to everyone who might come into contact with sick poultry, as has been done in past outbreaks of bird flu. The Belgian-based company Solvay, a major flu vaccine producer, is supplying the WHO with the vaccine used in the northern hemisphere this winter. But research published last week by the US Centers for Disease Control shows that this vaccine will not prevent most infections, because it is not effective against the Fujian strain now circulating.

The vaccine for the next southern hemisphere winter, which will be available in February, will protect against Fujian. But Solvay and GlaxoSmithKline have both told New Scientist that they must first supply the vaccine to contracted customers in countries like Australia, and are unlikely to have any left for Vietnam.

If the H5N1 does start spreading between humans, a specific vaccine against it will be needed. Two labs, the National Institute for Biological Standards and Control (NIBSC) in the UK and St Jude Children's Research Hospital in Memphis, Tennessee, have each made an H5N1 vaccine virus in cell cultures which could be used to mass produce a vaccine. Neither have been tested yet against the specific H5N1 strain found in Vietnam but both protect animals against similar strains.

Standard production methods do not work for H5N1 vaccines, partly because the virus kills the chick embryos normally used to grow flu vaccine. Instead, the labs used a technique called "reverse engineering", which involves using genetic sequences called plasmids.


Patent issues

The reverse engineering patent, however, is held by the biotech company Medimmune of Gaithersburg, Maryland, and the plasmids used are patented by various companies, all of whom will be entitled to payment if their property is used to make a commercial product.

Wood says he does not know how the experimental vaccine can possibly be put into production quickly when there are complicated patent issues involved. "You can't sort these things out when there's a pandemic sweeping the world."

"If people felt we were facing a pandemic situation, we would waive intellectual property rights," says Jamie Lacey of Medimmune, but it is not clear whether the other patent holders would do the same.

Of course, if a serious pandemic took hold, worries about patents would be swept aside. But delays in vaccine production caused by the initial uncertainty could cost many lives. Wood says there should be a clearly defined "trigger" point at which health authorities will be allowed to press ahead with plans for producing a vaccine without fear of violating patent laws.

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