BLOODSTREAM by Tess Gerritsen, MD, Pocket Books, New York, 1998, 464 pages, $7; Simon & Schuster Audio Books, read by Jan Maxwell, 3 hrs, 2 cassettes, $18.

GRAVITY by Tess Gerritsen, Pocket Books, New York, 1999, 346 pages; Simon & Schuster Audio Books, read by Campbell Scott, 4 ½ hours, 4 cassettes, $25.

Tess Gerritsen, MD, an internist who left a successful practice to rear her children and try her hand at writing, wrote her first book, Harvest, the chilling tale of the Russian organ harvesting Mafia in 1996 (Reviewed in Sacramento Medicine, Jan 1998). She wrote her second book, Life Support, the following year (Reviewed in Sacramento Medicine, June 1998) in which she addresses a number of medical issues—peer review, hospital discipline, doctors as owners of free-standing surgery centers, and just plain ruthless hospital medical/administrative politics revolving around an outbreak of Creutzfeldt-Jakob disease during the Mad Cow epidemic. She now treats us with two more quite different medical thrillers and may never examine another patient because her writing has undoubtedly relieved her patient care responsibilities.

In Bloodstream, Dr Claire Elliot moves with her high school aged son to the quiet resort town of Tranquility, Maine, to shelter him from both the big city and the lingering memory of his father's death. After taking over the practice of a physician who has left, she finds herself, and her son, in an uneasy situation. Her son has a skate board accident, his best friend, Taylor, lands one in his face, and his skateboard from his late father, lovingly taped together which is his sole memento of all he left behind, is confiscated. He wants to return to Baltimore. But Taylor’s violent behavior is not an isolated incidence. As Dr Elliot becomes involved in a strange pattern of periodic violence in this community, she decides to stay and try to find out what is going on. The dogs bring in a human femur, followed by a tibia and a child’s skull. She gets involved with what was thought to be a medical examiner’s case when the bones are shown to be too old for the ME and it becomes a anthropology examiner’s case. When she finally gives up and is ready to return to Baltimore, her son refuses. The author interweaves their lives with a tale of cyclic changes in the weather, rains, and floods to recurring epidemics and unusual microbes that affect the minds of the townspeople and cause disturbing aberrant and deadly behavior. This book reveals Gerritsen's command of medical intrigue within an array of circumstances. The reader of the audiotape, however, does not deliver the tension and immediacy of the story that Gerritsen's previous audiotape readers did, or this book did quite well.

In Gravity, Gerritsen changes pace from terrestrial to the extraterrestrial. Emma Watson, a brilliant research physician, has been training for years for the NASA mission-of-a-lifetime–studying living beings in space. Her estranged husband, Dr Jack McCallum, has been grounded and cannot share their dream. They have rekindled their love, and as the space shuttle passes over Houston, she waves to him and is convinced he is waving back.

As the astronauts on the international space station (ISS) share the status of the experiments at micro-gravity with the new team of astronauts, they find that microbes have infected their laboratory mice. The mice develop red sclerae, convulse, and die. The Japanese astronaut, Check Kinichi, is bitten by one of the mice as he works with them. He develops hemorrhagic sclerae, nausea, vomiting, seizures, and cardiac arrest. When the Discovery Shuttle relieves part of the crew, Kinichi’s body is taken aboard. As the Shuttle is leaving, its delta wing damages the ISS and pressure is being lost. The ISS crew tries to repair the damage through extra-vehicular activity (EVA) while, Discovery returns to earth with the sealed corpse.

While the new team works with the cultures and fresh mice, other astronauts sicken. The air is filled with desperation as they work to find the cause of the illness which is further complicated by green infected culture floating past them as they try to decontaminate. Dr Emma Watson receives an email that the senior investigator of the experiment, Dr Helen Koenig, telling Watson that the study is to be aborted, the cultures incinerated, and the ashes ejected them from the ISS. NASA thinks this is bio-terrestrial terrorism. Dr Koenig disappears.

Meanwhile the corpse on the shuttle swells up, the bag bursts and spews forth deadly organisms. The astronauts become ill and become too sick to lower the landing gears and Discovery lands on its belly. Immediately the Army takes over, a large tent is placed over the shuttle, fully hooded scientists begin decontamination, and NASA is no longer in charge of ground or space activities.

Dr Jack McCallum then follows the trails to Dr Koenig's laboratory, gets new leads, and is running against the clock to save his wife and the crew stranded in space. He learns that the problem–a single cell marine organism, an Archaeon, was originally found at 19,000 feet underwater on an asteroid. What happens to an organism that can live in deep multi-atmospheric gravity when it is brought to one atmosphere? And what can go wrong when that organism is taken to zero gravity?

Gerritsen weaves an unbelievable chain of events involving different work habits and tensions of astronauts from different countries confined in close quarters on a multi-national space station, a microbe that enlarges at zero gravity even after the host is dead, an epidemic and quarantine in a space station, burr holes in space trying to save an enlarging infected brain, the challenges of intubation and CPR at weightlessness, to how an organism can incorporate the host’ DNA to become a chimera with microbe, mouse, leopard frog, and human DNA, and therein lies the cure. And, finally, how is a husband to catch a ride into space to rescue his wife becoming ill with only 36-72 hours to live?