Russia has recently offered medicines and vaccines to help the United States fight a spate of anthrax cases. Russia has more experience than most countries in dealing with anthrax -- it was the site of one of the world's worst outbreaks in 1979, when at least 66 people died of the disease following an accident in a germ-warfare plant in Sverdlovsk.

In April 1979, people in the Soviet city of Sverdlovsk started collapsing and dying from a mysterious illness.

City authorities hosed down buildings and streets, believing some sort of industrial spillage might have caused the spread of the invisible killer germs. But the death toll continued to rise -- at least 66 people died over the course of two months -- and suspicions mounted that something far more insidious was at work.

The city was sealed off. Mass vaccinations and antibiotic treatments were ordered. The authorities finally acknowledged the cause of the deaths was anthrax.

The official version of the time -- put forward by then-local Communist Party boss Boris Yeltsin -- named the source as anthrax-contaminated meat.

But others, including the U.S. administration, suspected the real source was a military facility in the city thought to be a biological weapons factory.

It wasn't until 1992 that Yeltsin, by now Russia's president, admitted the outbreak was caused by an incident at the plant. Around the same time, a team of Western and Russian scientists visited Sverdlovsk, now called Yekaterinburg.

They looked at autopsy samples and plotted where all the known victims were located on the day of the incident. What they found was that the victims -- who all died of inhalation anthrax -- were situated along a very narrow line downwind from the plant.

What's now believed to have happened is that technicians at the plant neglected to replace a filter, allowing some anthrax spores to escape.

Alison Dale is a specialist in biological and chemical warfare at London's Center for Defense Studies. She says it's hard even now to pin down exact details of the incident, as any research has to rely on records from the time. Some of these were confiscated and others may not be reliable.

But Dale says that in one aspect, the incident's legacy was clear -- demonstrating how potent a weapon anthrax could be: "At the time there was a particular direction of the wind that carried [the anthrax spores] in one direction, [and] actually limited the amount of deaths and infections it caused. It showed that under the right conditions and in the right environmental conditions, a particular strain of anthrax could be used and disseminated via inhalational anthrax."

The long period between the first death and the last -- six weeks -- baffled some people at the time who suspected inhalation anthrax was the cause. But some have concluded that the original hosing-down meant to clear the city of germs in fact appears to have set off a second wave of exposures.

Dale says that the specific wind and weather conditions present in the Sverdlovsk incident showed anthrax is difficult to target with any precision.

"We cannot use this particular case to say that every time anthrax is released via aerosol, or if another accident occurs like here in the Soviet Union, where it was released through an air filter -- there's no guarantee that every time that happened there would be a specific [number] of deaths. That couldn't be guaranteed because people couldn't completely guarantee specific meteorological conditions.[So] it did prove that anthrax is very useful as a weapon, that it could spread and is odorless and not visible. It could be spread easily enough through the air and it maintained its strength and virulence through an air filter. [But again], a lot of investigations that have been carried on throughout the years have shown that there are a lot of drawbacks to it as well."

As for the Sverdlovsk plant, it was dismantled in the 1980s and production moved to a facility in Stepnogorsk in Kazakhstan, which has denied any involvement in the anthrax cases discovered in the U.S.

The Sverdlovsk anthrax was hauled across Russia in sealed containers before being dumped on an island in the Aral Sea and doused with bleach.

It is believed that the anthrax could remain dangerous for several generations, possibly even longer. Studies done in the United States and England indicate that natural anthrax can exist in the soil for over 100 year. It isn't known how long weaponized anthrax can exist outside of the laboratory.

Anthrax Disaster - 1979
Anthrax Germs
Life Cycle of Anthrax
Actual Death Toll Not Known
Bio Hazard

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