One of the most gripping novels in the "Hot Zone" style I have ever read is "Rabies" (Besnilo) by Borislav Pekic.
The genetically engineered Rabies virus with a double protein envelope becomes extremely easy to transmit (biting is not neccessary any more) and spreads from one victim to another extremely fast. The virus gets turned loose at the London's Heathrow Airport.
Soon, the airport is closed and quarantined and the (thick long) novel tracks a number of characters stranded at the airport, from scientists trying to figure out what is happening, and physicians trying to help the victims, through airport personel and passengers to a pet dog. Overthe course of a thousand pages, everybody dies. That is, except for the dog who manages to find his way out...
It is an amazingly chilling novel, exceptionally well-written, and predates the whole "Outbreak" genre by at least a decade.
Unfortunately, the book has never been tranlated into English. Now, the widow of the author has started a blog and is posting excerpts from some of his works, all translated into English. You can read the first four excerpts from "Rabies" on the blog:
Rabies (1st part), PROLOGUE – RHABDOVIRUS,
Rabies (2nd part), PHASE I – INCUBATION,
Rabies (3rd part), PHASE II – PRODROME and
Rabies (4th part), 1./II.
I hope more is coming. I also hope that the whole book will be translated and published in book form. It would make a killing as one of the earliest, best written, and scariest examples of the genre.