Sverdlovsk anthrax leak

The Sverdlovsk anthrax leak was an incident in which spores of anthrax were accidentally released from the on the southern edge of the city of Sverdlovsk (formerly, and now again, Yekaterinburg) on April 2, 1979. This accident is sometimes called "biological Chernobyl". The ensuing outbreak of the disease resulted in approximately 100 deaths, although the exact number of victims remains unknown. The cause of the outbreak had for years been denied by the Soviet Union, which blamed the deaths on intestinal exposure due to the consumption of tainted meat from the area, and subcutaneous exposure due to butchers handling the tainted meat. All medical records of the victims had been removed in order to avoid revelations of serious violations of the Biological Weapons Convention.

The closed city of Sverdlovsk had been a major production center of the Soviet military-industrial complex since World War II. It produced tanks, nuclear rockets and other armaments. A major nuclear accident happened in this region in 1957, when a nuclear waste facility exploded (known as the Kyshtym disaster), resulting in the spread of radioactive dust over a thousand square kilometers. The biological weapons facility in Sverdlovsk was built after World War II, using documentation captured in Manchuria from the Japanese germ warfare program.

The strain of anthrax produced in Military Compound 19 near Sverdlovsk was the most powerful in the Soviet arsenal ("Anthrax 836"). It had been isolated as a result of another anthrax leak accident that happened in 1953 in the city of Kirov. A leak from a bacteriological facility contaminated the city sewer system. In 1956, biologist Vladimir Sizov found a more virulent strain in rodents captured in this area. This strain was planned to be used to arm warheads for the SS-18 ICBM, which would target American cities, among other targets.

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