I have not read the book, but here is a link describing the plot.
When a young woman in New York City dies mysteriously after a trip to Europe, top epidemiologist Lowell Kaplan identifies the cause of death as the Marburg Virus—a fatal strain that has surfaced only once before in history.
Determined to trace the source of the disease, Kaplan follows a trail of intrigue from the labs of Germany to the jungles of Central Africa. But powerful forces are conspiring against him, determined to keep the secrets of the virus's origin kept deliberately under wraps. And with a global epidemic on the rise, Kaplan must go to unimaginable lengths to save mankind.
The Virus by Stanley Johnson | Goodreads