Should we destroy smallpox forever, asks WHO?

The World Health Organisation is meeting to decided the fate of the last two known remaining stocks of Variola, the virus that causes the deadly human disease smallpox.

Smallpox is one of only two viral diseases to have been eradicated in history (the other being Rinderpest - although this is yet to be officially confirmed). At its height, smallpox killed 30 per cent of those infected. However the success of a global vaccination campaign meant that it was finally declared eradicated in 1980.

Since then, the WHO has led a campaign to destroy existing stocks of the smallpox virus to minimise the risk of accidental release - an eventuality feared particularly by developing countries, who would be hardest hit by a resurgence in smallpox.

But the initial target date of complete destruction - 1993 - has been pushed back repeatedly under pressure from developed countries led by the United States. They want to keep the samples for research.

Today, only two laboratories retain stocks of Variola: the US Centres for Disease Control and Prevention in Atlanta, Georgia and the Russian State Research Centre of Virology and Biotechnology in Koltsovo, Novosibirsk.

The WHO's 193 member states are meeting in Switzerland to debate when smallpox should be destroyed. The aim is to build a consensus, since the WHO's resolutions are not legally binding. Here are the arguments for and against destroying Variola forever.

SMALLPOX SHOULD BE SAVED

We need to keep Variola for research. The existing smallpox vaccine, while effective, is unsuitable for people with compromised immune systems (such as those with HIV). Research into improved anti-viral drugs for treatment and safer preventative vaccines is still ongoing.

We need effective vaccines against smallpox because there could be stocks of smallpox whose existence is not yet known. There is also the possibility rogue states or terrorists could be hoarding secret stocks of the virus, with the intent of a biological attack.

As the US secretary of health Kathleen Sebelius argued in the New York Times, it is too early to get rid of the last two known stocks. To do so would jeopardise the research advancements being made. Only once the "safe and highly effective vaccines and antiviral treatments" for smallpox are developed should the last stocks be destroyed.

Destroying the smallpox virus would be pointless anyway, since it is now possible to recreate it from its genome, which was sequenced in 1994. That means destruction of the Variola stocks would be more symbolic than a practical protection against a new outbreak.

SMALLPOX MUST BE DESTROYED FOREVER

Developing countries have most to fear from a renewed outbreak of smallpox and they are right to be concerned. The risks far outweigh the possible benefits from research, which is no longer producing useful results anyway.

In 2007, the WHO said that scientific curiosity alone is not enough to retain the stocks; there must be clear evidence that research will have tangible public-health benefits.

Well, there is no such evidence: research has hit a dead end. Dr DA Henderson, the man in charge of the smallpox eradication program from 1966 until the last case in 1977, told the BBC: "We have done all of the productive research that we can do.

"It has been discussed fully and thoroughly by people around the world. Now is the time to destroy the virus as a further deterrent to anybody ever again producing it or using it."

People who want to save Variola say the virus can be recreated from its genome, anyway. But it that is true, then why do we need to keep it? If smallpox ever returns, we have the ability to produce as much virus for vaccines as we want from scratch. ·