SUCCESS BY SHOE LEATHER, INTUITION
13 Nov 2002
Source: Washinton Post, November 11, 2001.
Anthrax: New Jersey
Success by Shoe Leather, Intuition
No New Cases Recorded Since Oct. 31 Signals Apparent End to Outbreak in State
By Dale Russakoff, Washington Post Staff Writer
It was mid-October and investigators from the federal Centers for Disease Control and Prevention were already looking into anthrax cases in Manhattan and Boca Raton, Fla. No one knew where else the outbreak would hit, least of all Beth Bell, a senior CDC epidemiologist tapped to lead the next team, should there be a next team.
"What weather am I packing for?" she remembers asking in jest. After all, that's the one thing medical detectives usually start out knowing, whether they're going to Seattle to pursue an E. coli outbreak or to Philadelphia to find the source of Legionnaire's disease.
Early on the morning of Oct. 18, CDC lab tests revealed two new anthrax infections, both in postal workers in Trenton, N.J., where three letters containing anthrax spores had been postmarked. Bell had her destination.
In the life of the anthrax crisis, Trenton marks a high point of sorts in medical detective work, the place where the investigation has come closest to what epidemiologists call "the source" (and what law enforcement calls "the perpetrator").
But with all trails to the sender gone cold, health authorities have made little-noticed progress in the race against time and disease. Of the four cities where the CDC has sent teams to handle the anthrax outbreak, Trenton is the one that most vividly reveals the achievements -- and limits -- of the unsung, demanding work known as "shoe-leather epidemiology."
The signal achievement is that no one has died of the disease in a place where as many as 1,000 postal workers were exposed to anthrax spores from at least one of three letters sent to Senate Majority Leader Thomas A. Daschle (D-S.D.), NBC anchor Tom Brokaw and the New York Post. The letters were postmarked at a vast mail processing center near Trenton in Hamilton Township.
There have been seven cases of anthrax in New Jersey, including two women with pulmonary anthrax, the form of the disease that has claimed four lives elsewhere. But thanks to alert private physicians, a rigorous disease surveillance system staffed by state and federal teams, and lessons being learned daily, even hourly, in the fast-moving crisis, the women were diagnosed in time to be treated successfully.
An independent judgment by acting state Health Commissioner George DiFerdinando also may have been a factor. Although the CDC advised otherwise, DiFerdinando on Oct. 19 instructed all 1,000 postal workers at the Hamilton processing center to begin taking antibiotics as a precaution. There was no evidence at the time that postal workers could get pulmonary anthrax from a sealed, tainted envelope. And officials in Washington were following the CDC's advice not to treat postal workers.
"Epidemiologically, I had no data. This was a gut decision, and it's the decision I'm proudest of," said DiFerdinando, himself an epidemiologist. Within 72 hours, two District of Columbia postal workers would die of pulmonary anthrax and health officials would put thousands of District postal workers on antibiotics.
With no new cases since Oct. 31, the New Jersey outbreak is apparently over, at least for now. But it is not lost on medical detectives that they have accomplished only half a mission.
"What's unusual and very unsettling about this is that ultimately, none of us has control," said the CDC's Bell. "Usually we determine the source of the outbreak and we make recommendations to prevent additional outbreaks. But in this case, whoever this is could just send another letter."
Bell arrived here late on Oct. 18 with a three-person skeleton crew of shoe-leather epidemiologists, impeccably trained physicians who literally wear out their soles walking the streets to track the paths of disease. The approach is brilliantly effective when culprits hide in nature: tracing hepatitis to frozen strawberries or E. coli bacteria to Jack in the Box hamburgers (two cases Bell helped crack). But, experts emphasize, the technique was not designed to foil intentional acts.
As the CDC team arrived, the FBI was swarming in a suburban neighborhood in West Trenton whose letter carrier was one of the skin anthrax victims. This was seen as a big break because investigators assumed it meant the letter had been mailed on the carrier's route, a relatively circumscribed area. Like so many other assumptions, this one would prove to be unfounded.
Even amid the excitement, Bell and her team, which quickly grew to 17 CDC physicians and logistical staffers, focused on who was at risk of getting sick, not who was the culprit. Their time-tested approach involved dispatching multiple teams.
Among them is the shoe-leather team, which navigated central New Jersey's seemingly endless subdivisions, superstores and strip malls to track precisely how and where victims were being infected, and who might be next. Another team mobilized hospitals, doctors and public health workers across the state to watch for possible new cases and report them through a bioterrorism hot line already set up by the state. Most teams had state and local as well as CDC personnel, all reporting ultimately to Bell.
That Saturday, a physician in Mount Holly, N.J., called about a Hamilton postal worker he already had hospitalized with symptoms of inhalational anthrax, including fever and severe respiratory illness. The woman's condition was worsening and speed was essential. Bell called for blood and tissue samples to be airlifted to Atlanta for testing, only to find most shipping companies closed late on a Saturday.
Anticipating just such snafus, the CDC assigns logistics specialists to every outbreak investigation. One worked until 3:30 a.m. Sunday to get the samples en route.
The test results came back positive on Monday, with Norma Wallace, 56, already in serious condition, bloody fluids filling her lungs and choking her. As doctors at Virtua Memorial Hospital worked to save her, another New Jersey physician called to report an inhalational case, also a Hamilton postal worker, who was more quickly stabilized.
Meanwhile, the shoe-leather team was conducting exhaustive interviews to chart the risk pattern. Even if the FBI had already debriefed a subject, epidemiologists questioned the person themselves.
"You learn not to assume that all that needs to be known is known," Bell said. "Someone else might have jumped to conclusions. As we've seen, keeping an open mind is very important from the point of view of avoiding making mistakes."
An illustration came with New Jersey's third skin anthrax case, Hamilton postal worker Patrick O'Donnell, 35. The FBI interviewed him at length and reported that his job sorting magazines and flat packets kept him far from the path the tainted letters had traveled. This raised significant law enforcement and health questions: Was there a poisonous magazine or packet still to be found? Were all postal workers at equal risk, regardless of how far they were from the letters?
In an interview with a CDC epidemiologist, O'Donnell recalled that on Oct. 9, when the Daschle letter was postmarked, he worked overtime and was moved from the magazine sorter to the letter line. Now his illness confirmed, rather than defied, the risk theory the CDC was using to monitor those in the most danger: Everyone who had become sick was directly in the path of a tainted letter.
"The shoe leather is burning," one CDC epidemiologist exulted.
The seventh New Jersey case was the most puzzling: a skin anthrax victim at a Hamilton accounting firm, the state's only case that did not involve a postal worker. But unlike the New York case of Kathy T. Nguyen, a hospital worker who died without explanation of pulmonary anthrax, the mystery here was resolved when a mail bin used by the woman was found to have traces of anthrax.
With no clear explanation, authorities say she probably received a letter that crossed paths with the Daschle letter in the Hamilton plant and was contaminated.
They say the evidence suggests little risk to public health. "Clearly there must have been a lot of mail that had contact with [the tainted letters], yet we're seeing virtually no cases," said state epidemiologist Eddy Bresnitz. "So the risk to people had to be very low." Health authorities say it can be overcome if people wash their hands after opening letters.
An uneasy calm is settling in now. The Hamilton facility has been closed since Oct. 18, and doctors believe enough time has passed that no more cases will result from letters processed there. The state's seven anthrax victims all have been released from hospitals, fully recovered or on their way.
Now the medical detectives are shifting gears, from an outbreak investigation to a surveillance operation. Telephones, fax machines and computers now link every hospital in the state, and some in nearby areas of Pennsylvania and Delaware, with state and CDC epidemiologists. Every day, an inspection control officer at each hospital is assigned to report anything suspicious. As of this weekend, there were 125 cases on a watch list, but none considered likely to prove positive for anthrax.
"We're in pretty good shape if another letter comes through," Bresnitz said.
Meanwhile, Bell prepared to go home, to be replaced by another CDC team leader for this next stage. It was unsatisfying to leave without finding the source. But encouragement came from a bizarre place, a fortune cookie Bell opened while eating takeout Chinese food with her team on a recent night. Its message: Good news will be coming to you in the mail.