 Attempting to flee his guilt David escapes to China and bums around trying to forget. After six weeks Homeland Security interrogates the team at NORBAC wanting to know why David is in China. David is arrested by the Red Army and taken to a remote location where they want him to investigate a mysterious, virulent pandemic that is killing 2 out of 3 people. David eventually agrees but is appalled by the antiquity of the equipment and the secrecy he must work under. He gets a partial message to NORBAC and after some analysis they reply that the mystery bacteria is an unknown hybrid of two bacteria, one of which causes food poisoning and is not usually fatal! One useful fact provided by NORBAC is that the hybrid contains over 100 copies of the same gene for some unknown reason. David is baffled by the hybrid and doesn t understand the 2-in-3 death rate. The team in NORBAC are frustrated by the lack of communication with David and eventually come to the conclusion that the mysterious bacteria is not a hybrid but the granddaddy of the two individual modern bacteria. While watching an old man draw water with an old-fashioned lift pump, David has a flash of inspiration realizing that the repeated gene is for a pump and that the bacteria must be very old and live in very hostile conditions. With this information the team conclude that survivors are those that have had food poisoning previously. Back at NORBAC, Caroline entertains a new investor. She and Carlos are to attend the Toronto AIDS conference. At the conference she is attacked by a protester and infected with a previously unknown strain of HIV.