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Last Updated

10 Jan 2003

Source: Washington Post, February 11, 2002.

Agency With Most Need Didn't Get Anthrax Data

By David Brown, Washington Post Staff Writer

Canadian researchers last spring performed a series of experiments involving simulated "anthrax threat letters," one of which had recently arrived at a government office in Ottawa and proved to be a hoax.

The studies showed that if anthrax spores were finely powdered, a letter could release thousands of lethal doses of the bacteria within minutes of being opened. Furthermore, large amounts of material leaked out of sealed envelopes even before they were opened.

The research was the only rigorous, scientific effort to evaluate the risks posed by an event that actually happened less than a year later. On Oct. 15, an envelope loaded with anthrax spores was opened in the offices of Senate Majority Leader Thomas A. Daschle (D-S.D.).

By then, more than two dozen federal government employees knew of the Canadian studies, which showed, in brief, that a real anthrax threat letter was a far more dangerous weapon than anyone had believed. Within days, a dozen more people were informed of the now highly relevant experimental findings.

In all, bioterrorism and civil defense experts in a half-dozen agencies had the information. An agency that didn't have the information, however, was the one that could have used it the most -- the Centers for Disease Control and Prevention.

CDC epidemiologists, who had the lead roles in formulating a public health response to the unprecedented attack, didn't learn of the Canadian studies until early November. By then, the anthrax outbreak was almost over.

"It would have been good to have that information," Bradley A. Perkins, the CDC's lead anthrax investigator, said recently. "We were clearly dealing in a low-information environment."

David A. Ashford, another of CDC's anthrax specialists, said at a recent scientific meeting: "This experiment was shocking in that it showed how high the doses could be from envelope delivery."

How it happened that the agency with the most need for the information got it last is a story of bad luck, misinformation, incorrect assumptions and simple forgetfulness. Whether that made a difference is impossible to say.

Senate staffers in Daschle's office -- many of whom had anthrax spores detectable in their noses -- were given prophylactic antibiotics immediately after the letter was opened. Postal workers were offered the drugs six days later, when it was clear that two mail-sorting centers the letter had passed through were contaminated with spores. By then, though, several postal workers had developed the disease; two of them eventually died.

"Had we known early on about the Canadian experiments, would that have pushed us to prophylax people earlier? Maybe," said Larry Siegel, senior deputy director for medical affairs for the D.C. Department of Health. "Would it have mattered? We don't know."

As it was, more than 10,000 people took preventive antibiotics, and none became ill with anthrax. Siegel termed that "one of the biggest and most effective public health interventions that's ever been done‚... and one I think we can be proud of."

Asked whether the information would have led to a different strategy toward the postal workers, Sally Davidow, a spokeswoman for the American Postal Workers Union, said: "I don't think we can begin to know the answer to that. It was a tragedy that the two men died."

For his part, Perkins doubts the Canadian findings would have led to an earlier recommendation for antibiotics. The reason is this: When earlier that month two people in a newspaper office in Florida developed inhalational anthrax (one fatally), no postal workers became ill, even though the source of the bacteria in that outbreak was also thought to be a bioterror letter.

"I think the weight of the decision‚... would [still] have been based on the field observations in Florida," Perkins said. "Whether having this information would have tipped the scales of decision-making to a more conservative approach is in the realm of speculation at this point."

The Canadian research was done in two places – at a military lab in Alberta called Defence Research Establishment Suffield (DRES), and in Ontario by police-fire-health department workers calling themselves the Ottawa-Carleton First Responders Group.

The Alberta researchers used "weapons-grade" spores of Bacillus globigii, an anthrax bacterium simulant obtained from the U.S. Army. They put it in envelopes containing letters, and opened the envelopes in a special chamber equipped with air samplers. The researchers counted spores in units called LD-50s -- "lethal dose 50 percent" -- which is the dose that has a 50-50 chance of infecting and killing a person.

A person opening a letter and standing over it for 10 minutes would inhale 480 to 3,080 LD-50s, depending on how much powder was in the envelope and whether one used a high or low estimate for the LD-50s. Factoring in heavy breathing from stress, a person might inhale more than 9,000 LD-50s, the researchers found.

People can become infected by doses smaller than a single LD-50, and can survive doses that are many LD-50s. Doses in the hundreds or thousands, however, will kill virtually anyone unless preventive antibiotics are begun immediately.

"‚'Passive' dissemination of anthrax spores from an envelope presents a far more serious threat than had been previously assumed," the scientists wrote in their report.

The Ottawa researchers used fluorescent fingerprint powder as a stand-in for anthrax spores. Unlike their Alberta colleagues, they also recorded what happened when a letter was simply carried around the office.

"Contamination was present on the desk, papers, file folders and pen prior to opening the envelope (contamination was concentrated at the corners of the envelope where it was leaking out)...‚. Potentially contaminated persons are not limited to those in direct contact with the envelope and/or its contents," they wrote.

The results of the Alberta research were presented at four meetings of American, Canadian and British military biodefense experts. The first was on May 31, and the last on Oct. 17 (at the Canadian Embassy in Washington), two days after the Daschle letter was opened.

The findings from the Ottawa experiments were less widely disseminated. The one time they were presented to Americans was in mid-May in Canberra, Australia, at a meeting of civil defense experts.

Representatives from the Federal Emergency Management Agency and two branches of the military were at that meeting. The FEMA employee, upon returning, shared the Ottawa study (and about 30 other reports presented at the meeting) with contacts in the Public Health Service and Environmental Protection Agency. Immediately after the Daschle letter arrived, the State Department's counterterrorism office -- which had sponsored the American delegation to the Canberra meeting -- passed the information on to the FBI, Secret Service and U.S. Capitol Police.

Officials at some of the agencies say they have no record of those briefings. None of the people who recall them -- including about two-dozen Defense Department employees -- passed the information on to the CDC. They either assumed, or had been mistakenly told, that officials there already knew.

(The one exception is an officer at the U.S. Army Medical Research Institute of Infectious Diseases at Fort Detrick in Maryland, who said he called the CDC within days of the Daschle letter. But the three people he believes he may have talked to don't remember the call.)

One of the Canadian researchers tried to inform the CDC but was unsuccessful.

On Oct. 9, he sent an electronic copy of the 17-page Alberta study (which also contained a brief description of the Ottawa experiments) to Richard B. Kellogg, head of the CDC's laboratory response network. An attached note said, "In light of current events, we thought you might like a copy."

That occurred as the agency was frantically responding to the Florida outbreak. Kellogg said he was getting hundreds of e-mail messages a day and working 16-hour shifts, often away from his computer. He didn't notice or open the message until told of its existence two months later.

He is hesitant to criticize his Canadian colleagues. But he did advise: "In the middle of an emergency, do not do things in a perfunctory way. There was no red flag on this, and I was dealing in a red-flag world."

The CDC finally learned of the findings on Nov. 1, when a professor of epidemiology at the University of Minnesota sent Perkins a copy of the Alberta report. Perkins read it and immediately invited two of its authors to Atlanta to present the findings in detail. In the space of a month, they visited twice.