Issue Date: September 26, 2016
After Amerithrax: Biodefense in a post-9/11 America
The ringing woke him up. It was years ago, but Tom R. Slezak still remembers.
The Lawrence Livermore National Lab scientist didn’t normally get phone calls in the middle of the night telling him he was needed at work. And he didn’t normally jet off aboard a military transport after arriving at the lab. When he did fly, he normally knew where he was going, how long he’d be gone, and why he was leaving. But this was October 2001. Nothing was normal in America.
The weeks following the Sept. 11 attacks unleashed a new terror on the U. S. Hours before Slezak got his call, a photo editor in Florida died from anthrax caused by white powder containing Bacillus anthracis spores sent in the mail.
More anthrax cases would follow, caused by letters tainted with spores from a potent strain of the bacterium and addressed to prominent politicians and news organizations. One was intended for NBC news anchor Tom Brokaw.
The toxic envelopes had targets, but they killed indiscriminately. Five people died before Thanksgiving: the Florida photo editor, two employees at a D.C. postal facility, a hospital worker from the Bronx, and a 94-year-old woman in Connecticut who authorities believe handled cross-contaminated mail. The letters infected at least 17 more.
On that October night, Slezak’s plane was headed to Washington, D.C. He was part of a team tasked to install a system to identify biological threats, such as anthrax, in case of a larger attack.
Billions of dollars and 15 years later, the country has better tools to bolster the capabilities of the labs and crews called on to protect citizens against biological weapons. And the way officials think about biothreats has evolved since 2001. Still, despite these advances, gaps remain in America’s biodefense according to those serving on its front lines.
When the letter arrives
Systems like those Slezak helped set up are now installed nationwide in more than 30 American metro areas as part of the federal BioWatch program. These instruments constantly collect airborne particles that officials regularly analyze for biological threats invisible to the public.
Historically speaking, however, there are far more alarms raised by letters and packages with visible suspicious contents than by BioWatch’s aerosol collectors. The polymerase chain reaction (PCR) assays performed on samples from the BioWatch network have detected potentially dangerous organisms 149 times between 2003 and 2014, according to a 2015 report from the U.S. Government Accountability Office. Subsequent testing proved none of the hits were a public health risk, though, with most being triggered by nonpathogenic microbes that resembled lethal ones.
For comparison, the Federal Bureau of Investigation was called on more than 1,600 times to investigate incidents involving white powder letters between 2006 and 2012.
Most white powder incidents are hoaxes. In the years since, the U.S. hasn’t seen anything like the 2001 anthrax attacks, sometimes referred to collectively by their FBI case name, Amerithrax.
But responders must take every incident seriously. The exact execution of a response varies between different cities and states, but there is a general blueprint.
To learn about it, C&EN spoke with David Ladd, who has 35 years’ experience in emergency response, with 17 of those in the realm of hazardous materials, or hazmat. He’s now the director of hazmat emergency response for the Massachusetts Department of Fire Services.
When someone gets a suspicious piece of mail, their reaction generally is, and should be, to call 911, Ladd says. The call alerts local police, fire fighters, and emergency medical technicians, who are the true first responders, Ladd says.
They will typically then call in a hazmat team, whose members may have additional training and gear, including personal protective equipment. Although they are not first on the scene, they are still referred to by many as first responders.
FBI field specialists and public health labs that belong to the Laboratory Response Network, established by the Centers for Diseases Control & Prevention, are also typically involved in responding to a suspected biological attack.
These labs are prepared to identify suspicious substances and, if the threat turns out to be real, to guide treatments and a broader public health response. The FBI coordinates law enforcement efforts to find the source of the threat.
This response framework, however, does leave room for variability, especially when it comes to training, technology, and communication, which concerns Ladd. Ideally, all of the groups responding to suspicious package calls are talking to one another to handle a threat as safely and efficiently as possible. But building up the trust and relationships between agencies to do that takes time.
Ladd explains that his teams and the various groups that could become involved in a response started working together to prepare for biological threats in the late 1990s. At the time, there had been a spike in cases of women’s health clinics and Planned Parenthood offices around the country receiving anthrax letter hoaxes.
Then, following the 2001 anthrax attacks, that multiagency planning grew into what Massachusetts calls its Joint Biological Threat Response System: A consensus response plan forged with input from first responders, the FBI, public health labs, and others, including the National Guard.
That system now helps keep everyone on the same page, Ladd says. “We rely very heavily on ongoing communication between the stakeholders,” he says. But he adds that he’s been fortunate to work with a community that’s invested the time and money to build those relationships.
“To this day, I have conversations with people in various jurisdictions from both the responder side of the equation and the public health part of the equation that have no relationship with the other,” Ladd says. This can create situations where two groups are working toward the same goal of protecting the public without knowing or trusting what the other is doing.
The biodetection divide
First responders and public health labs not only have different types of tools and training, but those tools and training are subject to different levels of oversight and scrutiny.
On the public health side, CDC has worked with state and local labs to form a Lab Response Network with standardized sample analyses and other protocols, says Chris Mangal. Mangal is the director of Public Health Preparedness & Response at the Association of Public Health Laboratories, or APHL, a nonprofit group representing public health labs nationwide.
“Whether you’re a lab in Florida or whether you’re a lab in Washington State, you’re running that same procedure,” she says. “What’s different in the first responder community is we haven’t necessarily seen that same level of standardization. We’ve also not seen an evaluation of the instruments that are being used.”
The tools first responders carry can run preliminary tests on a suspicious powder to help them narrow the possibilities of its identity. And there are a lot of instruments for first responders to choose from. Since 2013, researchers at Pacific Northwest National Laboratory have been publishing a product guide of these biodetection products. The latest edition, from 2015, details more than 60 products, and its PNNL authors indicate that the list is not exhaustive.
Although some of these tools are certified to meet certain standards published by independent organizations, such as the International Organization for Standardization, these are voluntary standards. The tools do not currently need to clear mandatory, federal approvals in the way medical devices are regulated by the Food & Drug Administration, for instance.
Furthermore, there are no standardized approaches to training on the equipment. “In some states, we see first responders doing repeat testing to the point where they may have used up all of the sample,” Mangal says. This leaves little to none of an unknown substance for public health labs to analyze using their battery of validated techniques, including PCR and culturing.
The APHL has been pushing for federal policies to standardize field testing by first responders. For example, in a position statement that the organization first published in 2003, the group states it opposes first responders relying on field screening devices “without a federally approved quality assurance program.” It goes on to say, “while APHL recognizes the potential usefulness of such kits and devices, their use without proper field validation and appropriate training is problematic.”
Ladd agrees with the call for federal guidance in standardizing training and quality assurance programs for equipment. In fact, he’s one of the people leading that call.
Response teams, he says, need to understand what level of decisions can be made using the equipment they have. Field equipment can help make short-term tactical decisions to minimize and contain an immediate threat, but the tools have limitations that must be understood. Misunderstanding these limitations has damaged trust in the quality of first responders’ assessments.
“One of the things that happened in 2001 that we’re trying to recover from today was that field technologies were being used to make public health decisions,” Ladd explains. “There were some false positives and, unfortunately, false negatives. More specifically, at the Brentwood post office there were some false negatives and people got sick.”
Field tests performed on Oct. 18, 2001, missed anthrax at the Brentwood postal facility in D.C., according to a 2004 U.S. Government Accountability Office report. The facility remained open and no one monitored the health of the facility’s workers. Two employees later died from inhalation anthrax and two more were infected. Authorities closed the facility on Oct. 21, 2001. It reopened just before Christmas 2003.
The tools of the trade
Still, in the wake of the anthrax attacks, first responders had unprecedented opportunities to receive federal grants to purchase biodefense equipment, including detection devices. A 2013 report estimated that the investment since 2001 would reach nearly $80 billion by the end of 2014, although the funds allocated to programs that were solely for biodefense totaled closer to $14 billion (Health Security DOI: 10.1089/bsp.2013.0047).
Manufacturers, in turn, provided a variety of biodetection options, spanning a wide range of prices and capabilities.
Since 2013, the PNNL biodetection product guide, which is now available as a mobile app, has been downloaded 14,000 times, says Richard M. Ozanich of PNNL. Ozanich is an analytical chemist by training and one of the product guide’s authors. The tools listed in the guide span from simple protein test strips sold for less than $2.00 apiece to field PCR instruments that cost nearly $40,000 for the base instrument.
Of course, there are performance trade-offs with the price differences. Protein strips rely on nonspecific, color-changing chemistry to tell a first responder whether protein is present in a suspicious powder. However, the test cannot say what that protein is and whether it belongs to a dangerous pathogen.
If the strip changes color, “that could be anthrax, that could be ricin, or that could be beef jerky,” Ozanich says. Ricin is a toxic protein produced naturally in castor oil seeds that some criminals have sent via mail.
The two most popular field detection tools are immunoassays and PCR-based tests, Ozanich says. Immunoassays are more revealing than the protein tests and rely on specific antibodies to snare antigen molecules unique to a certain biothreat that may be present in a sample. Indicators, such as fluorescent dyes, chemically linked to antigen-antibody pairings alert testers that a threat has been detected.
Reagents for these assays cost dozens of dollars, although some of the tools do require special instrumentation demanding a more substantial one-time investment in the thousands of dollars range, according to the PNNL guidebook.
PCR-based assays look for sequence matches between snippets of DNA collected from a sample and those of known bioweapon pathogens. PCR amplifies, or replicates, the DNA segments and, as a result, the technique is orders of magnitude more sensitive than immunoassays. Although field PCR instruments can sell for tens of thousands of dollars, the cost of screening reagents is comparable to those used in immunoassays.
What first responders expect of their biodetection tools and what they can afford vary by jurisdiction, further complicating the challenge of standardizing training. At PNNL, Ozanich hopes his team’s continuing work to independently study the tools available to first responders can help untangle that challenge.
The PNNL researchers are currently working to establish an ASTM International standard for biodetection field equipment. The society already publishes a standard for collecting samples of a suspected biothreat.
Although both are still voluntary standards, they show that standards can be developed for biodetection products and protocols, Ozanich says. He admits it will be challenging to install a sustainable system of standards that all parties agree on, but he is optimistic it will happen within the next decade.
Biotechnology used by public health labs and first responders has evolved tremendously since 2001. PCR assays are faster. Immunoassay performance has improved thanks to nanotechnology. High-throughput genetic sequencing now exists.
But no single technology is perfect. The rates of false negatives and false positives can still be reduced. Analysis time can be driven down. Sensitivity can be ramped up. And so the biotechnology that can aid in biodefense continues to evolve.
“You don’t necessarily know what you need to worry about.”
—Tom R. Slezak, scientist, Lawrence Livermore National Lab
Livermore Lab’s Tom Slezak, who helped install what would become the first BioWatch collectors in 2001, is still helping evolve new tools for biodetection. He’s been working with a team developing a microarray system that uses nucleic acid probes to scout for more than 12,000 unique species of viruses, bacteria, fungi, archaea, and protozoans.
The system uses arrays of 1.4 million probes, strands of DNA and RNA. Each probe encodes genetic information from a known infectious agent.
An automated instrument adds nucleic acid from a sample to each array after labeling the molecules with fluorescent dyes. If the sample is from a known agent, the array glows in such a way that allows a technician to determine the agent’s identity.
With 1.4 million probes, researchers can determine the specific strain of an identified species. But the time it takes to get a result from a sample could be improved, Slezak adds. Currently, the tool is a research product, not a diagnostic tool or field device.
But the product recently became commercially available and has just been “soft launched” by Thermo Fischer Scientific’s Affymetrix under the name Axiom Microbiome Array. For about $100 per sample, researchers can have Affymetrix run an analysis using the microarray, Slezak says.
The microarray represents how researchers are continuing to develop new tools for biodetection and new ways of thinking about biodefense. “You don’t necessarily know what you need to worry about,” Slezak says about biological attacks.
To identify a threat, assays such as PCR and immunoassays must contain probes for that particular organism’s unique biochemistry. Conventionally, those probes have targeted a handful of biological agents likely to be used in an attack. When Slezak started working on the microbial detection array in 2003, he says he was motivated by the question: What if we focus on the predicted top 10 threats but get attacked by number 17?
That kind of thinking is motivating not only the evolution of the U.S.’s biodefense technology since the 2001 anthrax attacks, but also its changing philosophy toward biothreats, says Michael Kurilla, who directs the National Institute of Allergy & Infectious Diseases (NIAID) office that oversees biodefense research.
“We used to think agent-by-agent, but the list keeps getting longer and longer,” he says.
Before and immediately following the attacks, many officials believed protective vaccines were the best course of defense for each agent. But by 2005, it became apparent that vaccinating the nation for anthrax was not a logistically or economically sound solution. Nor would it be for tularemia or many other possible bioweapon agents.
So the thinking began shifting toward therapeutics and diagnostics that would work for the threat that came into play—either from attackers or from nature—and not just for the handful of agents officials chose to focus on.
Vaccines are still in NIAID’s research portfolio, but the agency’s preparations have become more comprehensive, Kurilla says. Projects now include developing therapeutics active against multiple types of infections and learning how to use the biochemistry of a patient’s immune response to characterize and potentially identify an infectious agent and course of treatment.
In the past, responses to infectious agents have also been hampered by an inability to identify the organism.
Kurilla doesn’t see that happening anymore thanks to next-generation sequencing. If an unknown infectious agent has nucleic acid, he says, “we’re not going to miss it. And we’re going to find it pretty quickly.”
It’s reassuring to hear that confidence. However, it also stands in contrast to the concerns and uncertainty expressed by first responders and public health representatives over the lack of national standards for equipment on the scene of a suspected biothreat.
David Ladd of the Massachusetts Department of Fire Services has been thinking about those concerns for 15 years. Over the last 18 months, he’s developed a plan to bring standards into training and equipment evaluation. That plan is currently being reviewed by the InterAgency Board, an organization of first responders and federal officials.
Establishing those standards will take time, money, and legislation. It will also take his plan getting into the right hands if and when it’s published. Is he optimistic that all these pieces will fall into place? “Well,” he says, “I’m sure as hell going to give it a try.”
CORRECTION: This story was originally published using the former name of ASTM International and has since been corrected.
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