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Last Updated

03 Dec 2002

Source: New York Times, June 15, 2002.

Report Provides New Details of Soviet Smallpox Accident


A Soviet field test of weaponized smallpox caused an outbreak in 1971 that killed two children and a young woman before health teams disinfected homes, quarantined hundreds of people and administered nearly 50,000 emergency vaccine shots, a new report asserts.

The outbreak struck Aralsk, a port on the Aral sea in what was then the Kazakh Republic. The report says a ship doing ecological research sailed too close to a military smallpox test that sent out a deadly plume of germs, infecting a crew member who carried the virus back to the city.

Moscow has never acknowledged the outbreak or that it ever tested smallpox in the open air. But late last year, a former top official in the Soviet germ weapons program spoke of the incident in an interview with a Moscow newspaper, and Kazakh officials have recently been investigating the outbreak's origins.

Now a team of experts at the Monterey Institute of International Studies, drawing on formerly secret Soviet documents and interviews with survivors, has written a report on the Aralsk outbreak.

The team says the strain of smallpox virus appears to have been unusually potent and even sickened seven people vaccinated against the disease. The episode, the researchers say, raises questions about whether new vaccines or drugs might be needed if this strain were used in an attack.

"We know that the vaccine works well in the vast majority of cases," Alan P. Zelicoff, a team member who is also a physician and smallpox expert at the Sandia National Laboratories, said in an interview. "What the new data strongly suggests is that we have much more work to do on new vaccines and the development of antiviral drugs, none of which are available today."

In envisioning a smallpox attack, terrorism experts consider person-to-person contact a main threat. Members of the Monterey team said the blowing of germs in the wind suggested that a contemporary smallpox threat could be harder to combat and contain.

Dr. Zelicoff is to present a summary of the report today in Washington to federal officials who are developing guidelines on whether smallpox vaccinations should be offered to anyone besides the few researchers who now work with the virus.

The three victims who died in Aralsk, Dr. Zelicoff said, were all unvaccinated and developed the disease's rare hemorrhagic form. Usually fatal, it is characterized by heavy bleeding and normally accounts for one to three percent of smallpox cases. The seven survivors, he added, had received routine vaccinations earlier but nonetheless contracted mild to serious cases of the disease. Vaccination usually bars the crippling illness.

"This outbreak did not have enough cases, thank God, to clarify" hints that the strain was unusually potent, Dr. Zelicoff said. "But it at least makes the questions legitimate."

Members of the Monterey team said federal officials grew wary this week when told of the impending report out of fear that it would undermine the national push for 300 million doses of smallpox vaccine, the production of which is due to be completed late this year.

In a conference call on Thursday, Dr. Zelicoff reassured health and military officials that he would recommend more research rather than changes in vaccine production.

His presentation is nonetheless expected to cause a stir at the meeting today, which is public.

D. A. Henderson, a top bioterrorism adviser to the secretary of heath and human services, said he was skeptical of the Monterey report's conclusions and expressed confidence in the American vaccine. As for the Soviet one, too little was known, he said, to assess its effectiveness among Aralsk citizens in the 1971 outbreak.

"We don't know when they were vaccinated or whether they were successfully vaccinated," Dr. Henderson said in an interview. He added that the Monterey scientists were "jumping to far-reaching conclusions with scant information."

No country has divulged outdoor tests of the smallpox virus, which causes high fevers and usually kills one in three unvaccinated people. The disease was declared eradicated from human populations in 1980.

The United States ended routine smallpox vaccinations in 1972 and the immunity of those vaccinated before then is believed to have waned over time. Today, the protection issue is back on the public agenda as fears of germ terrorism have grown.

Only the United States and Russia now keep publicly declared stocks of the virus. But terror experts say impoverished Russian scientists may have sold the virus to foreigners.

Raymond A. Zilinskas, one of the Monterey report's authors, said in an interview that American officials should try to obtain the strain from the Russians in order to test the American vaccine's effectiveness.

"They're going to have to open up," Mr. Zilinskas said of the Russians. "We have to know what we're defending against." He added that the Russians undoubtedly still possessed the strain.

The report was written with the aid of Kazakh officials, who blame Moscow for the Aralsk outbreak. The document, a draft of which The New York Times obtained, is to be made public late this month or early in July.

Though it draws on old Soviet studies about the Aralsk outbreak, the report does not directly tie the epidemic to weapon tests but infers a link through circumstantial evidence and the perceived weakness of alternative theories, such as a natural epidemic.

By 1971, it notes, the Soviet Union had reported no outbreaks of the disease for a decade.

In an interview, Dr. Henderson suggested that a natural outbreak might have carried the virus to Aralsk from Afghanistan, where smallpox in 1971 was still endemic.

As evidence of a weapons link, the Monterey report cites an interview with General Pyotr Burgasov, a former official in the Soviet germ weapons program. Moscow News, a Russian publication, quoted him in November as saying the outbreak was caused by field testing of 400 grams, or a little less than a pound, of germs.

General Burgasov said the crew member on the research ship picked up the virus when it passed within 15 kilometers, or about 9 miles, of an off-limits isle. The Aral Sea island of Vozrozhdeniye housed the main outdoor testing area of the Soviet program to make germ weapons.

The smallpox test is said to have occurred on July 30, 1971, with the ship sailing nearby between July 29 and July 31.

Aside from his comments, no details of the putative test are known publicly. But scientists at the military base on Vozrozhdeniye Island routinely exposed animals to deadly germs and measured agent dispersal in open air.

These tests were legal in 1971, as no international treaty then existed that banned the development of biological weapons.

In researching the incident, Dr. Zelicoff of the Sandia National Laboratories was able to track down and interview the outbreak's first case, who was then a young fisheries expert, as well as the second patient, her 9-year-old brother.

Contrary to the official Soviet report, he said, she told him that she never disembarked from the ship, the Lev Berg, before returning to the home port of Aralsk. That, Dr. Zelicoff said, strengthened the idea that she picked up the virus from the wind rather than from a port of call.

As the youngest crew member, she told him, she worked most frequently on deck. Her job was mainly to cast nets to catch fish, which she then took below to a small laboratory.

After the outbreak began in Aralsk, health officials scrambled to contain the disease, according to a formally secret Soviet report reprinted in the Monterey study.

Nearly 50,000 residents of Aralsk were vaccinated in less than two weeks, and hundreds were placed in isolation in a makeshift facility on the edge of town where they could receive no visitors.

Travel to and from Aralsk was stopped, and many homes were disinfected, along with 18 metric tons of household goods.

The Soviet vaccine of that era was generally considered as effective as the American one.

In his section of the draft report, Dr. Zelicoff says the fact that the Soviet Union never reported the Aralsk outbreak to world health authorities "suggests a sinister source."

Another author of the report is Jonathan B. Tucker, a Monterey official and author of "Scourge," a book on the smallpox threat.

The public forum where Dr. Zelicoff is presenting a summary of the Monterey study is one of a series that the Centers for Disease Control and Prevention is holding to solicit opinions before two advisory committees decide whether to change recommendations on smallpox vaccination.

A policy decision is expected as soon as next week.