In the second part of the book, the narrative shifts to a monkey house in Reston, Virginia in 1989. The monkey house, officially known as the Reston Primate Quarantine Unit, is owned by Hazelton Research Products, a company that coordinates the import and sale of laboratory animals. On October 4, the facility receives a shipment of 100 wild monkeys from the Philippines. Two of the monkeys are dead upon arrival at the facility, but the remaining animals are placed throughout 12 holding rooms in the building.
Less than four weeks after the shipment’s arrival, the colony manager, Bill Volt, notices that a large number of the new monkeys are dying. Already 29 animals from the original shipment have died, with the majority of the deaths occurring in Room F. Bill Volt also notices that the heating and air-handling system in the monkey house is malfunctioning. He contacts Dan Dalgard, the consulting veterinarian for the facility, to see if he will examine and treat the monkeys.
When Dalgard arrives at the facility a few days later, he identifies two sick monkeys in Room F that seem to be feverish with droopy eyelids. Both monkeys die that night. When Dalgard returns to the facility to dissect the animals, he notices that both monkeys have enlarged spleens and blood in their intestines, but he is unable to identify a specific cause of death. Dalgard suspects that the monkeys may have died from an infectious agent such as simian hemorrhagic fever (SHF). Over the course of the next several days, several monkeys from Room F die nearly every night.
After dissecting one of the dead monkeys, Dalgard decides to send samples of the animal’s spleen and throat mucus to USAMIRRD at Fort Detrick. He contacts Peter Jahrling, a virologist at the Institute who specializes in monkey viruses and agrees to examine the samples. Much to Jahrling’s chagrin, the samples arrive packaged in nothing more than tin foil. However, after an initial examination of the samples, Jahrling provides Dalgard with a tentative diagnosis of simian hemorrhagic fever.
Determined to contain the outbreak, Dalgard euthanizes the remaining monkeys in Room F. When he dissects the animals, he is dismayed to discover that several of them appear to be perfectly healthy. Unsure if he has made the correct decision in killing the animals, Dalgard stores their bodies in the facility freezer.
Meanwhile, at the Institute, an intern named Tom Geisbert asks to examine the samples from the Reston facility. Geisbert enjoys sharpening his skills by looking at viruses, such as Marburg, and is anxious to tackle a new specimen. When Geisbert examines the flask with cells from the Reston monkey, he notices that the cells seem to be unrecognizably sick. He takes the sample to Peter Jahrling for a second opinion, but Jahrling concludes that the flask must have been contaminated with bacteria. Both scientists sniff the contents of the flask, but neither can detect the odor associated with contamination. Still, Jahrling maintains his original diagnosis of SHF and calls Dalgard to confirm.
After a weekend hunting trip, Geisbert returns to the laboratory, determined to confirm Jahrling’s diagnosis with visual evidence from the electron microscope. Using his diamond knife, he cuts tiny slices from the monkey sample, with each slice containing thousands of cells. When Geisbert examines one of the slices through the microscope, he is shocked to discover that each cell is crawling with a rope-like virus. His first thought is Marburg. Geisbert realizes that both he and Peter Jahrling may have sniffed a flask containing a deadly hot agent.
From the beginning of this section, Preston draws clear parallels between the Reston monkey facility and the vaccine factory in Germany where the Marburg virus first appeared in 1967. In both cases, a shipment of laboratory monkeys is exported to a facility for use in scientific research. Both shipments undergo minimal inspection, with the Reston shipment even arriving on site with two dead animals. With this parallel immediately established in the reader’s mind, Preston is able to imply the arc of the next several chapters.
In Dan Dalgard, Preston introduces a character who suffers from the same moral conflict as Nancy Jaax. When Dalgard euthanizes the remaining monkeys in Room F, only to discover that they are completely healthy, he feels as if he has betrayed his code as a veterinarian. Dalgard’s decision to store the monkey carcasses in the facility freezer demonstrates the guilt he feels in killing healthy animals. Rather than removing or incinerating the bodies, he elects to keep them in the facility, perhaps as a reminder of the sacrifice that he made, seemingly without cause.
By contacting Peter Jahrling, Dalgard also acknowledges that he is out of his depth with the number of sick and dying monkeys at the Reston facility. Yet, considering his profession, Dalgard’s lack of knowledge about the proper way to transport infected samples is unexpected and serves to foreshadow some of the bureaucratic issues that will plague the Reston operation. Fortunately, the tin foil-wrapped samples prove to be harmless to humans, but this seems to be yet another case of salvation by chance.
Significantly, it is an intern at the Institute, and not the expert virologist, who ultimately identifies the filovirus in the sample from the Reston facility. While Jahrling is content to keep the initial diagnosis of SHF, Geisbert is determined to obtain hard evidence through his electron microscope. This speaks to the recurring theme of human error as a cause of viral outbreaks as Preston asks the reader to consider what might have happened if Geisbert had not decided to reexamine the sample. Not only would the virus have quickly burned through the monkey population at the Reston facility, but, unchecked, it might have mutated and infected the human population to the same extent as Marburg.
While setting the scene for Tom Geisbert’s identification of the filovirus, Preston draws a clear comparison between the virus as predator and Tom’s weekend hunting trip. While Geisbert is hunting in the woods of Maryland, Preston suggests that another predator could be simultaneously hunting him. Although Geisbert is unaware that the flask contains a filovirus when he leaves for the weekend, the reader is still presented with a literary cliffhanger, as Tom’s fate seems to hang in the balance for the two days of his trip. This comparison foreshadows the argument that Preston will make later in the book: that the human species can be considered to be equally parasitic and even predatory as a filovirus.