The FBI and people like Tom Brokaw sought USAMRIID’s help with the anthrax letters for a reason. As Willy Sutton might have said, “That’s where the money is.” USAMRIID’s decades of biodefense experience and its specialized labs for containing highly hazardous pathogens made it the go-to place for the DoD and the nation during infectious disease crises, especially those related to biological weapons.
Over sixty years ago, leaders of the U.S. biological warfare program realized that they couldn’t just make weapons; they needed countermeasures against them too. You can’t make a weapon if your laboratory workers get sick. The late Bill Patrick, chief of New Product Development for the U.S. germ warfare program, told me that he could tell a weapon’s effectiveness by how many people working on it got infected.
From 1943 to 1969, over four hundred laboratory workers at Fort Detrick became infected with the agents they worked on in the laboratory, with tularemia, brucellosis, and Q fever leading the pack. The infections drove the push for safety innovations.1 So the army created the U.S. Army Medical Unit (USAMU) in 1956 for germ-warfare defense. Over decades, unit personnel developed and tested an array of diagnostics, treatments, and vaccines against biological weapons threats. They also established a lasting legacy of working on highly hazardous agents safely, as worker infections plummeted with advancing laboratory equipment, air-handling systems, use of vaccines, and understanding of how the agents spread. When President Nixon shut down the U.S. offensive weapons program in 1969, the defensive program continued with the establishment of an innovative new research laboratory at Fort Detrick: USAMRIID.
During my tenure as chief of the Division of Medicine at USAMRIID, I felt personally responsible for the safety of our laboratory workers. I wanted them to have the confidence that we would take care of them, as with any patient, without passing judgment on how they got infected during a laboratory accident. Preventing laboratory infections relies on multiple layers of protection, but nothing is foolproof.2 We try to minimize laboratory hazards as much as feasible and train people to mitigate risks, but laboratory accidents will continue to occur, because just like with airline crashes, most laboratory exposures result from human error. Nonetheless, USAMRIID has an incredible safety record, with only a handful of worker infections over decades, despite the deadly pathogens that its staff work on daily.
Pathogens don’t like to be contained. Their natural drive for survival requires them to infect in order to reproduce. So the government developed four “biosafety levels” based on the pathogens’ ability to infect lab workers to thwart the pathogens from meeting their end game to reproduce. Like the multiple barriers we cross for airport entry from the parking lot to ultimately boarding the airplane, safety precautions and laboratory entry restrictions tighten with each successive safety level from Biosafety Level 1 (BSL-1) to BSL-4.
At BSL-1 there are no specific restrictions because the organisms used don’t infect healthy people. Move up one level to BSL-2, where most hospital microbiology laboratories operate to work safely on familiar names like Salmonella, Staphylococcus aureus, hepatitis B, and HIV. Some of these pathogens can kill, but they don’t deliberately fly off the petri dish to infect through the air. They require an energy source—a dropped vial, a puff of air, a cough or sneeze—to get them airborne or provide an entry opportunity through the skin, gastrointestinal tract, or genitourinary tract. As an extra precaution, though, we wear gloves and a lab coat, wash our hands, and work with the agents inside a laboratory biosafety cabinet (a “hood”), about the size of a refrigerator lying on its side. Protected by a glass face shield on the front of the hood, workers reach inside below the glass through an air curtain that provides an invisible barrier to rebuff any organisms trying to escape.
At BSL-3 we cross the barrier into “containment” because certain deadly pathogens, like tuberculosis, Q fever, plague, anthrax, and VEE, preferentially infect through the air—but we have a treatment or vaccine for most of them. The constant whoosh of moving air heard inside containment labs comes from massive air handlers that maintain a vacuum and frequent air exchanges to keep the pathogens from taking flight outside the lab. High efficiency particulate air (HEPA) filters “clean” the air of very tiny particles, even viruses, so nothing can escape. Waste must be autoclaved, treated with disinfectant, steam sterilized, or incinerated before leaving the lab.3 Vaccines may be required or recommended prior to lab entry or work with a specific agent.
The animal rooms are the “wild west”—the most hazardous places inside containment but with insidious risk. Pathogens hijack the animals as hosts for replication and to help them spread when the animals cough up or excrete deadly organisms in their body fluids. Nonhuman primates (monkeys) can be especially vicious and take every opportunity to bite or scratch anyone venturing within an arm’s length of their cages. I’ve had my own close calls. The animals launch their arms suddenly out through the smallest openings to grab the closest object, often unexpectedly.
The deadliest agents, like Ebola, Marburg, and Lassa viruses, are unforgiving, and we have no vaccines or treatments to block them, so we need BSL-4, “maximum containment.” In BSL-4 we separate the person completely from the agent by confining the organism inside a “container” called a class III biosafety cabinet, or “glove box.” As in the movie The Andromeda Strain, scientists place the organisms inside the box and then work through specialized gloves attached to the box, so they don’t need to wear any other specialized protective equipment. This works well for smaller experiments but has less flexibility for larger animals or high-volume operations.
The second option is to put the scientist in a container, or “space suit”—basically a giant body condom—that receives pressurized air through a HEPA filter fed by hoses, similar to tire pumps, in the lab ceiling. Once connected to the air hoses, an air curtain sprays down across the face to protect the eyes, nose, and mouth, and air moves through a network of arteries to protect critical body sites such as the hands. If someone breaks a glove or tears the suit, the internal air pressure will spray any infectious pathogens away.
Calling the containers “space suits” is not too much of a stretch. Once the electron magnet engages and the stainless-steel door closes behind you, you are a captive without an easy, immediate exit. Your lifeline comes through air hoses, and you enter a private world cut off from the rest of the institute. You must trust your partner with your life, as you would a fellow astronaut. A slipup with a sharp instrument or an infected animal bite gives the pathogen the chance to replicate inside you as in the film Alien, with disastrous consequences for you and your partner, including an all-expenses-paid “vacation” locked up in the Slammer. It’s no accident that it takes months of training for certification to enter BSL-4 independently.
Having such critical laboratory containment assets has put USAMRIID on speed dial for national crises, whether it’s the White House, the FBI, the CDC, or the military calling. USAMRIID has shipped lifesaving botulinum antitoxins, provided vaccines to quell an outbreak of Rift Valley fever in Egypt, and diagnosed West Nile virus during the 1999 New York City outbreak. One USAMRIID senior scientist likes to say that USAMRIID is a “national insurance policy” against catastrophic infectious disease threats. One former commander called it the “nation’s Bio-911,” the emergency hotline to call for biohazard or bioweapon emergencies.
As the medicine chief, I found myself in the thick of many Bio-911 events, including some that came calling from the highest levels of the government.