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Last Updated

16 Dec 2002

Source: Washington Post, June 16, 2002.

Soviets Had '71 Smallpox Outbreak

Report: 3 Die, 43,000 Vaccinated After Test of Biological Weapon

By David Brown, Washington Post Staff Writer

In the summer of 1971, the Soviet Union apparently conducted an open-air test of a biological weapon containing smallpox virus. The experiment caused a smallpox outbreak that killed three people and required a massive vaccination campaign to confine it to a port on the Aral Sea, in Kazakhstan.

Details of the outbreak were immediately suppressed by Yuri Andropov, then head of the KGB and later the Soviet premier. Yesterday was the first time they were presented in the West, at a gathering of smallpox experts and public health officials at the National Academy of Sciences, in Washington.

The account was presented by Alan P. Zelicoff, a physician and biological weapons expert at Sandia National Laboratory in New Mexico. He used the official Soviet report on the outbreak, which recently came into American hands, and his interviews with two of the smallpox survivors to reconstruct the events. He described the account as "preliminary," with certain events inferred from circumstances and not proved.

Nevertheless, if correct, the scenario is the first evidence the Soviets field-tested a smallpox weapon, and the first evidence the work caused civilian deaths. (Accidents in the Soviet biological warfare program caused deaths elsewhere from plague, anthrax and the Marburg virus.) It also extends to about 25 years the period in which the Soviets had a smallpox biological warfare program unknown to U.S. intelligence.

Zelicoff said calculations of the rate of disease transmission to vaccinated people in the outbreak also suggests -- but does not prove -- the strain of virus might have been more transmissible or resistant to the protective effects of vaccination than other smallpox strains.

Traditionally, pox virologists have believed that differences in transmission in outbreaks largely reflect "host" factors -- that is, the health and genetics of the exposed people -- rather than virus factors. "With these data, you have to consider that it may be due to the strain of the virus -- and that idea has been anathema," he said.

Experts greeted the report differently.

Raymond Zilinskas, a former United Nations weapons inspector in Iraq who is now at the Monterey Institute of International Studies, said that it suggests the Soviets perfected airborne delivery of smallpox virus -- and that the capability may still exist.

"We are always talking about contagion [person-to-person spread]. Now we cannot dismiss the possibility of aerosol dispersal of the virus," he said.

However, the Department of Health and Human Services' chief adviser on bioterror preparedness, D.A. Henderson, said he did not "quite come up with the alarmist concerns" others have mentioned.

"From this report I see nothing that's new or that we don't already know about," he said at an Advisory Committee on Immunization Practices meeting at the National Academy of Sciences.

Zelicoff's presentation was one of many given to the ACIP, which is composed of academic and government scientists who recommend immunization policy to the federal government.

Although highly effective, the vaccine causes an unusually large number of side effects compared with other vaccines. It has not been used routinely in the United States since the early 1970s. The committee is deliberating whether the government should again make it available -- either to everyone, or to people with certain jobs, such as police, paramedics, nurses and doctors -- as part of the nation's defense against biological terrorism.

The last case of naturally acquired smallpox occurred in Somalia in 1977, and the last case ever in England in 1978 after a laboratory accident. The 1971 outbreak occurred midway through the campaign to eradicate the disease begun by the World Health Organization in 1966. Ironically, that project was first proposed in 1958 by the Soviet deputy minister of health, and the Soviet Union ultimately provided hundreds of millions of doses of vaccine to it.

Today, the only known samples of smallpox virus are stored in several sites in Russia and at the Centers for Disease Control and Prevention in Atlanta.

Zelicoff's account of the outbreak was this:

In August 1971, a government vessel named Lev Berg with a crew of 12 was collecting samples of water, plankton and fish as part of research on the declining fishery in the Aral Sea. (Once the world's fourth-largest inland body of water, the sea was shrinking in 1971, and today is largely gone because of diversion over many decades of water from the two rivers feeding it.) On board was a 24-year-old ichthyologist, who because of her age and position spent more time on deck than anyone else collecting samples.

In mid-August, when the ship arrived at Aralsk, its home port on the north shore, the woman became ill with a fever and eventually a pox-like rash. In late August, so did her 9-year-old brother. After several incorrect diagnoses, the cause of the illnesses was proved to be smallpox in mid-September.

In all, 10 people became ill. Two infants less than a year old died, as did the grade-school teacher of the young boy, who visited him during his illness. None of the people who died had ever been vaccinated. The seven people who survived had all been vaccinated, in some cases many years previously.

After smallpox was identified, the government closed the town. Trains from Alma-Aty to Moscow were kept from stopping in Aralsk. A tent city was put up, where about 250 people who had had direct contact with the cases were quarantined. About 43,000 people were vaccinated.

In their 60-page report on the outbreak, the epidemiologists at the local government "anti-plague institute" said the virus must have come aboard when the ship docked at ports in Uzbekhistan and Kazakhstan, which share the Aral Sea. No other cases were found. (Smallpox had not been seen in the Soviet Union since about 1960, although it existed in Afghanistan in 1971.) Furthermore, Zelicoff said that when he interviewed the ichthyologist last month in a two-hour telephone conversation, she said women were not allowed to leave the ship on those stops, and she did not.

Since 1936, the Soviet military had used an island in the middle of the Aral Sea, Vozrozhdeniye ("Resurrection") Island, as a site for open-air testing of biological weapons. In November, Pyotr Burgasov, an 86-year-old former general in the Soviet biological warfare program, told the Moscow News that "a powerful form of smallpox" was tested on the island, that in 1971 400 grams of it were present on the island and that a "mysterious death" had occurred.

"It turned out that a research vessel in the Aral Sea approached the island at 15 kilometers distance. It was forbidden to be closer than 40 kilometers," he said in the interview. He gave no details of testing.

The Soviet report of the outbreak was acquired by Americans last year, although details of how that happened also were not provided yesterday.