At 2 a.m., the Beltway is an open pasture. I was driving home from my shift at the emergency room the other night, replaying a mental tape of the past 10 hours and listening to the radio. The news turned to yet another report on suspected terrorists at our borders. As I sped through the darkness, the dire warnings brought flashing back my own brush with a biological nightmare.

That was several years ago, when our ER treated the victims of a suspected anthrax attack. Over the course of many hours, we did our jobs--caring for these unique patients, as well as the usual load of ill and injured--in a nervous, reflexive dismissal of the possible danger to ourselves. As I headed home afterward, without the preoccupation of work to keep my fears below the threshold of consciousness, I suddenly broke out in a cold sweat: I could just as easily be back in the hospital, quarantined with patients and colleagues, waiting to find out if we were contaminated and going to die.

One night in March 1992, sometime around 10 o'clock, a newly dumped boyfriend with a grudge and a couple of brewskis on board decided to get back at the girl who had ex'ed him. He burst into her Tysons Corner living room carrying a small glass vial filled with an amber-colored liquid and announced that it was anthrax. She and the 10 other folks in the apartment at the time, he said, were goners. "If I break this, we all die in 48 hours," he said. Then he smashed the vial and splattered the fluid.

The cops who responded to the 911 call subdued the guy and told the victims to stay calm until EMS arrived. They brought in the Fire and Rescue people, who called in the Hazmat experts, who, in turn, put our emergency room on alert.

Luis Eljaiek, one of two attending physicians on duty with me that night, happened to pick up the incoming call and thus ended up as the hot doc. He would be in charge of decontaminating the 11 victims and coordinating their medical care. He signed his patients over to the other doctor, and crawled inside a biohazard uniform for the unforeseeable future.

The ambulance entrance and one trauma room were immediately sealed off by some hastily arranged tarps and duct tape. Luis and the staff inside awaited the arrival of the biologically hot victims. The rest of us--doctors, nurses, patients and paramedics--would be left to watch from the outside.

Eleven o'clock Sunday night is a bad time to shut down a busy ER because of a vengeful loser playing with possibly toxic toys. It meant that other rescue squads and ambulances in Fairfax County would have to be diverted to other hospitals until we were declared clean.

When the call came in, I'd been in a patient's room. I returned to find a sci-fi-ish plastic curtain taped over a section of the ER and Luis, a tall, solidly built Cuban, flailing around in an equally improbable plastic spacesuit. "What the hell's Luis doing?" I asked.

"Some guy sprayed his girlfriend with anthrax."

I remember laughing. "Get outta here."

"No, seriously." Word was, the guy worked in a biological supply laboratory of some sort and he very well could have had access to a lethal germ. At a time like this, no information is reliable; that's just what we heard.

The instant consensus in the ER was that an aggravatedly stupid joke like this couldn't be real. No doubt the officials from the FBI, DoD, CIA, FEMA, EPA and probably a couple more agencies who had by that time been made aware of the situation also felt that way, but they had the responsibility of proving the attack to be a hoax--or rumbling into action if it turned out to be real.

What evolved was a very controlled out-of-control situation. The victims started arriving, a few at a time, brought in by EMS units. After an hour, the original 11 cases were joined by nine of their neighbors, who had seen the police tape and wanted to be checked out and treated as well. Luis's first task, inside the ER's hot zone, was to hose them down as they arrived--after they had been stripped naked, their clothes sealed in a biohazard bag for eventual destruction--to clean them of any potentially deadly anthrax spores. Then they would all need initial medical assessment and antibiotics. Fortunately, we were aware that the most effective antibiotic to treat anthrax is a common one.

The ex-boyfriend with the vial was, of course, one of those being washed down. Agitated, drunk and uncooperative, he was a handful. As Luis and the nurse grappled with him, Luis bent over and suddenly felt the seat of his protective pants rip open. So, thanks to this guy he was trying to treat, Luis could be sentenced to die in a bio-safety isolation tank.

Or could he? There is a fair amount of information about anthrax that doctors are aware of--but we hadn't had to use it in the ER before. I don't know how much Luis had a chance to bone up on before he had to go into action. As for me, my clearest recollection about the disease was: It's kind of fatal.

Outside the hot zone, it was beginning to feel like the Twilight Zone. Facts were in short supply, rumors were not. In the first hour or so, all we knew for sure was that the guy said he had anthrax. He was a jilted boyfriend. He wasn't a boyfriend at all. He was drinking. He wasn't drinking. He was a scientist at a local biological supply lab. A maintenance worker. It was a break-in. There were two victims. A dozen. Two dozen. Fifty. Police, Hazmat guys, military types, identifiable by sweatshirts with official insignia, piled into the ER, with little to contribute beyond "I'm in charge, I've got jurisdiction." "No, I'm in charge! It's my jurisdiction!"

Our job was to keep everybody calm, maintaining the illusion that we were on top of things. But chaotic forces were building. Nurses, docs, paramedics and techs traded nervous jokes, which were misheard as facts and passed on. Thank God: no press.

We heard the broken vial was being sent somewhere federal for identification, but no one could confirm that, either. I took a stab at calling the hospital's microbiology lab. "Can we send you some stuff and have you tell us if it's anthrax?" I asked, only half seriously. The guy in the lab asked me to hold a minute. Then he said he couldn't do it--he wasn't sure which requisition slip to use. Call tomorrow. I left it to the feds.

The second hour produced no better information than the first. It became harder to carry on routine patient care as the situation chewed up resources. The decision came down that all the victims had to be hospitalized. Finding even five available beds on a busy night, even in a big hospital like Fairfax, can be a chore. Finding 20 was a crisis all by itself. There easily could have been five or six other ER patients waiting to be admitted. And on the hospital floors there was an understandable reluctance to take this particular bunch--God only knows what kind of rumors were circulating up there.

Among the ER staff, the original "this is stupid, let's get back to business" attitude was long gone, not that it had ever affected our response in a meaningful way. And it became harder to keep questions at bay: Were they going to let us go home? Was anything going on behind the tarps that they weren't telling us? Was I in any danger? Were any of us?

About this time, Luis, the backside of his pants taped shut, heard some chilling news. The perp actually worked at Fort Detrick in Frederick, Md., home of the army's infectious disease and bio-warfare branch, and had not only knowledge of but access to an entire range of violently lethal germs. Now he knew the threat was credible--but he didn't know what it really was. This guy could just as easily have made off with something worse than anthrax: Ebola. Hantavirus. Smallpox. Hazards for which there were no antidotes.

Suddenly those rivulets of water running off the victims were a lot scarier--were they being drained effectively, or was anything leaking somewhere beneath the hospital? Luis's torn pants were no longer a bad joke--they were potentially a tragic detail in the newspaper story about a heroic doctor's untimely death.

I peeked through the window to the action side of the tarp and saw a chilling scene straight out of a movie: the jerky movements of the doc and the nurse in their spacesuits, spraying down a nude, fearful victim, soapy water sloshing everywhere. The fear and doubt in the victim's eyes were matched by that in Luis's.

Sometime around 2 in the morning, it was established that since all the victims had arrived in a somewhat controlled manner, no one on my side of the tarp was in any danger. We could come and go as we pleased without fear of spreading contamination. I tore out of there as soon as I could.

Meanwhile, the shattered vial had been transported back to Fort Detrick. Sixteen hours after the first call to 911, we found out what it had contained: Ginseng oil.

No anthrax, no Ebola. A hoax.

The next day, I relearned a lot about anthrax that I wish I had remembered earlier. It would have eased my fears somewhat. Outside living organisms, bacillus anthracis exists as an inert spore. Once the spore is inhaled, it enters the immune system, and can kill by causing devastating inflammation in the chest, known as mediastinitis. It does not cause pneumonia and, therefore, does not produce respiratory droplets. As a result, an infected victim will not spread it to others by breathing or coughing (unlike, say, plague and smallpox, which are contagious).

The only effective way to disseminate anthrax is to aerosolize the spores and produce a fine mist. Depending on your goals as a terrorist (or disgruntled ex-boyfriend), this may or may not suit your purposes. In our case, and had we been able to act on the assumption that anthrax and only anthrax was involved, this would have been good news: Chances were negligible that any of us could have been infected by the liquid touching our skin and they were down to zilch that Luis could have caught it from one of the victims.

Another key fact: There is a three-to-five-day incubation period while the spore wakes up. Antibiotics administered during that period stop the disease cold. So even if these folks really had been exposed, none of them was ever likely to get seriously ill. But neither Luis, nor I, nor anyone else in the ER that night, with the possible exception of the perp, knew that at the time.

I have since learned that our drama was one of the first documented episodes of an anthrax hoax carried out on American soil. Since then there have been more than a hundred others. Not everything is a hoax, though: Saddam Hussein started his collection with stock purchased from a biological warehouse in Rockville.

Anthrax is out there, and so are the wackos and hatemongers. An anthrax attack is a tricky, dangerous stunt to pull off but, as we learned that night, an awesome array of resources can be summoned almost instantly to manage the consequences. It felt and looked chaotic, but in fact a lot of trained professionals did exactly what they had to do. Thanks in part to this ghoulish joke, and others like it, the response to any future events should be even smoother. All the same, I can't help but hope that the very near future doesn't force us to prove it.

J.B. Orenstein is a pediatric emergency physician at Inova Fairfax Hospital.

The Numbers

The FBI calls them "WMD cases" (for weapons of mass destruction): the threatened use or procurement of chemical, biological or radiological materials with intent to harm others. According to testimony two months ago before a Senate subcommittee, such incidents have increased in recent years.

In 1996, the FBI counted 37 WMD cases in the United States; in 1997, 74; in 1998, 181, and in the first 10 months of this year, "more than 225." In roughly three-quarters of those cases, the perpetrator threatened to release a biological agent, usually anthrax--probably because anthrax is widely recognized and feared.

None of the threats was determined to be "credible," according to the FBI.

But no threat can be trusted to be a hoax. So training and cooperation between health and law enforcement agencies continues to increase. According to the Annals of Emergency Medicine, 53 percent of residency programs in emergency medicine include formal training in the response to bio-terrorism.