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Labs researcher sleuthes smallpox mystery

Sandia’s Al Zelicoff searches for clues to Soviet super smallpox strain

The evidence mounting against the Russians isn’t definitive. But it’s enough to make Labs senior scientist Al Zelicoff (5320) and other nonproliferation experts uneasy.

For almost a year, Al has been trying to track down what he believes is a virulent strain of weaponized smallpox tested by the Soviet Union in the early 1970s — a biological weapon Russian officials today won’t acknowledge even when confronted with evidence from their own archives.

The international arms control community wants the Russian government to disclose details about the strain, which Al believes is a particularly potent modification of the virus, so the rest of the world can defend itself from it.

Without the genetic code of the strain, he says, preferably gleaned from a live sample provided by the Russians, doctors and pharmaceutical companies are unable to develop vaccines to blunt the virus’ effects should it fall into the wrong hands.

Last week, Al appeared on ABC World News Tonight and NBC Nightly News and was interviewed by a US News & World Report reporter about the alleged super strain.

The missing strain became newsworthy early last week when the CIA announced it was following leads provided by an informant who claimed a late Russian bioweapons researcher might have given the smallpox strain to Saddam Hussein’s government during a visit she made to Iraq in 1990.

A report published in June by the Monterey Institute of International Studies’ Center for Nonproliferation Studies (CNS), titled "The 1971 Smallpox Epidemic in Aralsk, Kazakhstan, and the Soviet Biological Warfare Program," details efforts by Al and others to track down the alleged strain. The full report is available at

The report’s centerpiece is Al’s 10-page epidemiological analysis of a smallpox outbreak in fall 1971 in Aralsk, a port city on the northern shore of the Aral Sea in what was then the Kazakhstan Soviet Socialist Republic.

Al’s investigation of the outbreak was aided by new details from a previously secret Soviet medical report turned over late last year to US officials by Prof. Bakyt Atshabar, director of the Mosgut Aikinbaev Kazakh Scientific Center of Quarantine and Zoonotic Infections in Kazakhstan.

These official Soviet documents (circa 1971), also included in the CNS report, include autopsy reports, pathology reports, containment tactics, and an official Soviet analysis of the outbreak’s source.

The outbreak

From August to October 1971 in Aralsk, 10 cases of smallpox were recorded, and three people died. Russian officials quarantined the city for weeks.

Nearly 50,000 people were vaccinated in less than two weeks. Many were isolated in a makeshift hospital on the outskirts of town. Homes and belongings were decontaminated or burned.

The person believed to have introduced the virus to Aralsk was a young female ichthyologist who had just returned from a four-week research expedition on the Aral Sea aboard the Lev Berg, a small fishing boat.

According to official documents, she was bed-ridden with a fever, headache, and muscle aches aboard the ship beginning Aug. 6, five days before returning to Aralsk on Aug. 11.

Before public health officials diagnosed smallpox as the cause of her illness six weeks later, the young woman had exposed her nine-year-old brother, who had exposed others.

Soviet officials kept the outbreak secret, failing to report it to the World Health Organization as required.

Official accounts

How the young woman, known as "Patient 1" in Al’s report to obscure her identity, was exposed to the virus remains a matter of contention.

The Russians claimed, and still do, that Patient 1 most likely was exposed when she disembarked from the Lev Berg at one of three ports during the expedition.

Although today smallpox is eradicated from human populations, in 1971 it persisted endemically in Afghanistan and theoretically might have been brought to Aralsk or to any of the Aral Sea’s port cities by migrants.

The Soviet documents relate that Patient 1 left the Lev Berg at each port. They detail how she bought a dress, a towel, and some fabric in one city. She possibly contracted smallpox at one of the ports, which she visited eight, six, and two days prior to the appearance her symptoms on Aug. 6, the documents contend.

A different story

But Patient 1, age 54, now a citizen of Kazakhstan, says she never left the Lev Berg during the expedition. In fact, she claims, female crew members were forbidden from disembarking. She says she first experienced symptoms on her return to Aralsk on Aug. 11 or 12, not on board the ship on Aug. 6 as stated in the official Soviet account.

The details of her visits to the port cities were fabrications, she told Al, who located her and interviewed her by phone, with help from interpreter Elena Bloomstein (5327), in May 2002.

No one else aboard the Lev Berg became ill, so it is unlikely Patient 1 was exposed to smallpox by a crew member who had disembarked from the ship, says Al. And no outbreaks were reported in any of the Aral’s ports in 1971, so it seems unlikely the virus made its way to the Lev Berg without infecting a single local, he says.

Biowarfare island

In addition, says Al, the average latency period of smallpox is 13 days, with a range of 11 to 15 days.

According to Patient 1 and official accounts of the Lev Berg’s expedition, 13 days prior to the onset of Patient 1’s symptoms, about July 30, the ship was sailing somewhere south of Vozrozhdeniye Island.

International arms control experts know the Soviet Union conducted offensive biological weapons testing on the island, known as Voz Island, beginning in 1936. By 1971, it was the major proving ground for the Soviet Union’s bioweapons program, according to former Soviet officials who worked on the island.

Although historical documents do not detail an open-air test of smallpox on Voz in 1971, the Soviets are known to have been experimenting with the variola virus (the causative agent of smallpox) as an offensive weapon at the time, and several tests of other biological agents dispersed by aerosol sprayers and exploding bombs are recorded during that time.

Al believes the Lev Berg might have strayed too close to the island as smallpox viral particles, alighted on the wind by a Soviet weaponizing additive, floated across the ship’s decks, where Patient 1 netted fish day and night.

A November 2001 interview in the Moscow News of Gen. Pyotr Burgasov, a former chief sanitary physician for the Soviet Union, indicates the Soviet government knew of the mishap. (See "Interview supports Voz Island hypothesis" below left.)

A super strain?

To bolster his case, Al also compared the newly released epidemiological data from the Aralsk outbreak with data from a documented natural outbreak in Kosovo in 1972, and with other data compiled from more than 10,000 cases of smallpox in India published in 1964.

In Aralsk, a significantly greater proportion of infections were of the severe and often fatal hemorrhagic variety of smallpox, he says. In addition, although infants are very rarely stricken by hemorrhagic smallpox, in Aralsk two of the ten victims were infants, and both died from hemorrhagic infections.

The seemingly high percentage of hemorrhagic cases and the skewing of the distribution to very young children suggest that an unusual strain of the virus was responsible, Al’s report states.

Further, five of the six adults infected in Aralsk had been vaccinated against smallpox, even though the vaccine is usually 90 percent effective at protecting those exposed. And twice the expected number of "household contacts" of infected persons also became infected, says Al.

Circumstantial evidence

Although Al’s conclusions are limited by the small numbers of victims, the Aralsk data at least suggest that an unusually virulent strain might have caused the outbreak, possibly a vaccine-resistant strain, he says.

"For the first time, there is clear circumstantial evidence that the Soviets not only ‘weaponized’ smallpox, but succeeded in aerosolizing it and, it appears, ‘hardening’ the virus so that it maintained its infectivity as it traveled downwind over a distance of at least 15 kilometers," Al’s report concludes.

"Only a detailed analysis of the Aralsk strain with the most modern tools of molecular biology can guide public health officials and defense planners in formulating appropriate policies and prophylaxis, which may include a concerted effort to produce new vaccines," it states.

With Russia eager to be accepted by the West, it adds, "it is long past time for Moscow to reveal the detailed history of the Soviet BW program. Helping to resolve the numerous uncertainties about the 1971 smallpox outbreak in Aralsk would be an important step in that direction."

Appeal for openness

In July, Al co-signed a letter to Lev Sandakhchiev, Director of VEKTOR, the official Russian repository lab for smallpox. The signatories included Joshua Lederberg, winner of the 1958 Nobel Prize in Physiology and Medicine; Peter Jahrling, Principal Scientific Advisor, US Army Medical Research Institute of Infectious Diseases (USAMRIID); and Tom Monath, Chief Scientific Officer of vaccine maker Acambis Inc.

The letter urged Sandakhchiev to encourage the Russian government to report details of any open-air smallpox tests in 1971 on Voz and to cooperate with international authorities to turn over samples of any undisclosed variola strain.

"This unfortunate outbreak occurred over 30 years ago, under the Soviet regime, and prior to the coming in force of the Biological Weapons Convention," the letter states. "A new era is upon us, and we hope that information from these dangerous experiments can help us to work with you to prevent the use of smallpox as a biological weapon. We know that you share with us a passionate attachment to that goal. We have little interest in raking up the past, except where that is necessary to protect our future."

Al says he continues to press the issue with Russian and US officials. He’s briefed numerous government officials, including an individual at the deputy undersecretary level in the US Department of Defense. More important, says Al, Jahrling, the United States’ most respected smallpox expert, has taken the message even higher.

Al’s analysis "provides strong circumstantial corroboration of suspicions that Soviet bioweaponeers conducted open air testing of smallpox virus on Vozrozhdeniye Island" and "elevates the theoretical concerns about variola virus as an agent of mass destruction to a new level," wrote Jahrling in a commentary of the CNS report.

"The main significant finding in Aralsk was that smallpox could be successfully aerosolized over long distances," says Al of his study conclusions. "That the virus strain in Aralsk may have caused worse-than-usual disease is suggested, but not proved, by the statistical analysis.

"I believe that eventually our Russian friends might come around," he adds, perhaps as the result of political pressure, a desire to do the right thing, or both. "After all, this is one area where their help could truly be important and life-saving," he says.