Anthrax strain traced to ’93 plot
The Denver Post, Feb. 17, 2003
By Diedtra Henderson, Denver Post Science Writer
Monday, February 17, 2003 – The world’s most popular animal vaccine, produced by a Colorado company, was the unsuccessful “weapon” chosen by a doomsday cult in Japan that two years later killed 12 and sickened thousands by releasing nerve gas in a subway station.
An Arizona researcher told colleagues about the 1993 anthrax attack in Japan at Sunday’s session of the American Association for the Advancement of Science’s annual convention in Denver.
The talk showcased the same type of genetic fingerprinting being used to unravel the source of anthrax that killed five in the United States in 2001. It was the first bioterror attack in the U.S. involving anthrax but is unlikely to be the last using that or another infectious agent.
An army of investigators have fingered the Ames strain as the one responsible for America’s unsolved anthrax attacks, which infected 22 people, mostly mail handlers.
Tracing the source of anthrax, though, is difficult because recognizable differences in vials from various labs are etched into the DNA fingerprint by mutation. The problem is that the pathogen mutates so slowly it’s not clear whether anthrax can be tied to a specific lab by studying mutations alone.
“Especially if it’s sitting in spores in someone’s freezer … there’s little chance to get mutations,” said Paul Keim, an anthrax expert at Northern Arizona University in Flagstaff.
Other techniques, such as having a detailed database of pollen native to specific regions of the country, could define where the killer anthrax came from, if unique pollens cling to anthrax samples held in evidence.
FBI officials said Sunday that good databases are apt to be key to solving biological crimes – whether they are anthrax-related or caused by someone intentionally spreading AIDS – and announced plans to build a database of bacteria and viruses that can be used for comparison if such a crime occurred.
It was a database that simplified the task of tracking the source of the anthrax used by Japan’s Aum Shinri Kyo cult members in the summer of 1993. In that case, the anthrax matched a sample already in an anthrax database created to help track the former Soviet Union’s supplies.
Japanese public health authorities had been tipped off about an eight-story concrete building the cult owned in a crowded area of Tokyo. Neighbors lodged 160 complaints about a terrible stench coming from the building, Keim said.
Public health officials investigated. They snapped photos of a smoke plume rising from the building’s roof and scraped slime samples that had oozed down its walls. But they couldn’t get inside the doors. Their worry: the fearsome cult and its psychotic leader were boiling the bodies of assassination victims.
“It seems like you could get a search warrant for that,” Keim said.
As it turned out, the cult was growing anthrax in the basement in a vat and was pumping it from the building’s roof. Meanwhile, cloaked in the banality of a white utility van with special vents, the cult spewed more anthrax-tinged gas through neighborhood streets.
“If authorities at the time had recognized this as a bioterrorist attack, perhaps the sarin gas attack would have never occurred,” Keim said.
Instead, the anthrax plot wasn’t known until cult members released nerve gas in one of Tokyo’s most congested subway stations at rush hour in 1995. After their arrests for that incident, cult members mentioned the earlier anthrax attacks.
Four of five vials containing the slime had already been analyzed by Japanese scientists looking for proteins that would have confirmed rumors the cult processed human remains at the building. One dusty vial remained in a public health refrigerator.
Keim cultured the sample in a petri dish filled with sheep blood. The sample blossomed with the telltale shape of anthrax blooms. Of the 4,000 activated spores that crowded the petri dish, the lab ran DNA fingerprints for 48, matching them to the Sterne strain vaccine produced by Colorado Serum Co.
“The cult was using a vaccine strain, which wasn’t virulent,” Keim said.
While some would fault the cult for incompetence, Keim doesn’t think that was the problem. The group’s members included graduate level microbiologists.
Former cult leader Shoko Asahara had such a tight hold over his followers, he could raise money by selling cups of his bath water for $100 a gulp. And he swiftly killed, whether the dissenter was an enemy or cult member.
“They were afraid to tell him they didn’t have the material,” Keim surmises.
Keim, under a non-disclosure agreement with the FBI, would not talk about the anthrax case that was on the minds of most at the Sunday symposium – the 2001 letter cases.
Each envelope contained a letter decorated with ominous lines, like “09-11-01 … You can not stop us. We have this anthrax. You die now. Are you afraid?”
The anthrax samples Keim’s lab analyzed were sent blind. In addition, he said he does not want to make a defense attorney’s life easier.
“There are certain areas that are just off-limits,” he told reporters. “Pretty much anything that’s directly related to the case I won’t talk about. I don’t want to be on the stand and have a defense attorney reading me what I said to you.”