First Reston outbreak period (October–December 1989)

The First Reston outbreak period (October–December 1989) turns a lethal epidemic among imported monkeys into a crisis of uncertain human risk. At the Reston Primate Quarantine Unit, sick workers, infected animals, and gaps in what investigators knew forced decisions before the virus’s behavior in people was understood. The episode ended without human casualties, but four caretakers were later found to have been infected without becoming ill, and evidence from the monkey house led researchers to take airborne transmission seriously.

The outbreak becomes a human-risk emergency

By the crisis’s sharpest escalation, Dan Dalgard believed that two of the facility’s four workers were ill: one had a heart problem, while another had fever and vomiting and was being taken to hospital. Dalgard feared that these symptoms might indicate infection. The workers had also gone about ordinary life outside the facility, visiting public places and friends. The possibility that an infection might have reached their families and wider community made the uncertainty more urgent. Dalgard had previously hoped that the absence of human illness meant there was no substantial human danger; now, he felt the monkey house had to close.

He went to the Hazleton Washington offices, told the general manager what had happened, and broke down while recommending that the operation be shut and transferred to the Army. The general manager agreed. United States Centers for Disease Control and Prevention personnel, already at the offices to monitor exposed employees, also heard Dalgard’s recommendation that the building and its animals be turned over to the United States Army Medical Research Institute of Infectious Diseases. The question was no longer simply how to manage diseased monkeys: it was who could safely take responsibility for the facility and what to do about a possibly infected worker.

Transfer of the monkey house

The proposed handover exposed a conflict between speed and liability. The company’s senior managers approved the transfer but wanted the Army’s agreement to legal responsibility in writing. C. J. Peters rejected that condition, regarding the situation as one requiring a clear, rapid decision rather than extended negotiations. Dalgard agreed to send a simple letter transferring the monkey house. Peters and General Philip Russell reviewed and signed it without taking it to Army lawyers; the signed letter was faxed back, and the facility passed into Army control.

That decision committed Jerry Jaax to lead a larger biohazard team into a building containing hundreds of animals. Before the operation, Jaax assembled soldiers and civilian staff, explained that they would handle blood and sharp instruments, and directed them to use disposable biocontainment suits. He asked for volunteers and made clear that no one was required to go. No one withdrew. Because Ebola posed a particular danger to pregnant women, he excluded a pregnant sergeant from the team. On the morning of the entry, Jaax organized partners and assigned the order in which teams would enter. At the monkey house, Gene Johnson disclosed to the assembled workers that two caretakers were ill and that one had neither been bitten nor injured by a needle. If that man had Ebola, Johnson warned, infection through the air was a possibility. Jaax had not previously been told about the sick worker; the disclosure transformed the team’s understanding of the risk as it prepared to enter.

Killing the animals and securing the site

The response involved 450 monkeys. On December 7, the last one was killed and placed in a biohazard container. One monkey had escaped capture, and Jaax spent two or three hours trying to corner it before it became trapped behind a cage and was anesthetized. The operation’s final sweep uncovered another complication: a storage-room chest freezer held roughly ten or fifteen frozen monkeys from Room F, the original outbreak site, along with vials of sedative. The team removed these materials for decontamination rather than keeping additional samples. Across the operation, workers collected 3,500 clinical samples.

The cleanup continued beyond the animal-handling operation. On December 18, the decontamination team scrubbed the building with bleach until paint came off the concrete floors. For the final fumigation, workers sealed exterior doors, windows, and ventilation openings with duct tape and plastic. They placed patches containing harmless bacterial spores around the building to test the treatment, then used thirty-nine electric frying pans to heat disinfecting crystals and release formaldehyde gas. With the building sealed, the gas remained inside for three days, penetrating air ducts, offices, furniture, and equipment. The building that the Army had considered destroying was instead subjected to a comprehensive decontamination process.

Infection without illness

The apparent absence of human disease did not mean that no caretakers had been infected. Four men who had worked at the monkey house eventually tested positive for Ebola Reston virus. They included Jarvis Purdy, Milton Frantig, and John Coleus, as well as a fourth worker. Coleus had cut his thumb; the others had no known cuts, yet the virus had entered their bloodstreams. None recalled becoming ill, and the infection eventually cleared from their bodies. There were no human casualties, but the contrast between infection and symptomless recovery left a central question unanswered: why had the virus devastated monkeys without producing recognized illness in these men?

The distinction between the known injury and the other exposures shaped the scientific significance of the episode. Researchers concluded that the men without cuts had likely been infected through contact involving the lungs, and the pattern among the caretakers strengthened the case for airborne spread among the monkeys. The account presents this as a serious possibility, not a complete explanation of every infection. The outbreak therefore ended with both reassurance and alarm: the virus had not caused human deaths, yet the workers’ infections showed that it could enter people without an obvious wound.

A local crisis in a wider ecological frame

The book places Reston within a broader concern about emerging viruses and changing environments. It describes tropical forests as reservoirs of diverse life, including viruses, and connects the appearance of new infections with ecological damage and human settlement at forest edges. It also discusses the primate trade: wild animals were captured, handled, and crowded together in systems that could expose workers and animals to unusual viruses. These passages establish a wider context for thinking about animal-to-human emergence, but they do not prove that a particular ecological change or route caused the Reston outbreak.

That uncertainty is part of the period’s significance. The response had to proceed while the source and transmission of the virus remained unsettled, and the threat was judged from evidence gathered inside the facility: sick monkeys, ill workers, and infections in men who had not all suffered identifiable cuts. By December, the animals had been killed and the building fumigated. The episode’s ending was operationally decisive but scientifically incomplete: the immediate danger was contained, while the meaning of symptomless human infection and the possibility of respiratory spread remained matters of concern.