Search Engines: Serendipity: Hardly a poxy matter

IF YOU ever find yourself in Bentley, Gloucestershire, then you might like to visit the Cowpox Temple, a small building erected to commemorate the achievement of Edward Jenner. At the age of 19, Jenner was chatting up one of the local milkmaids, who casually mentioned to him that she would never contract smallpox because she had already had cowpox, a well- known piece of Gloucestershire folklore. Although Jenner thought nothing of it at the time, he became a doctor and several years later realised the significance of the milkmaid's tale. The relatively harmless cowpox virus was enough to stimulate the immune system into defending the body against the more deadly, but related, smallpox virus.

In 1796, he extracted some pus from the blister of a milkmaid suffering from cowpox, and injected it into James Phipps, a healthy eight-year-old. The following day he injected some smallpox into the boy, who suffered no ill effects. Jenner had demonstrated the power of inoculation. The now-famous discovery earned him a reward of pounds 20,000, and his hero status was acknowledged by Napoleon, who released two English prisoners when the doctor interceded on their behalf.

While smallpox vaccinations saved many lives in the 19th century, the virus remained at large, killing two million people in 1968. Eventually, a coordinated worldwide effort eradicated the disease in the 1970s, and for the last two decades the only remaining viruses have been kept in one Russian and one American laboratory. The scientists have been conducting a series of experiments, such as identifying the virus's genetic make- up, but all along it has been assumed that the viruses have been on death row. Tomorrow, which happens to be Jenner's 250th birthday, the World Health Assembly meets, and it will be discussing a plan to destroy the remaining virus stocks by 30 June 1999.

Those in favour of extinction claim that as long as laboratories retain stocks there is a risk of smallpox escaping. Indeed, the last smallpox death was a photographer who was infected at Birmingham University Medical School in 1978. There is also the possibility of terrorists using stolen viruses as a biological weapon. Those against destroying the smallpox stocks argue that terrorists might already possess smallpox viruses, and therefore researchers should continue to develop better vaccines. Also, it is possible that a variation of smallpox, perhaps monkeypox, will one day cross over to humans. Hence some scientists want to continue studying the live virus in preparation for such an occasion.

Both America and Russia have recently declared their reluctance to destroy their smallpox viruses, and so even if the World Health Assembly votes in favour of destruction, it is not clear that it can enforce the decision. A compromise, which might avoid embarrassment, would be a stay of execution, deferring the issue for a year or two.