If you're looking for a taut, tense story about the outbreak of an alien plague and the desperate efforts of a band of scientists to isolate and defeat it ... then I suggest reading the original The Andromeda Strain novel, by Michael Crichton. Or, if you're video-centric, check out the 1971 movie adaptation. In either case, skip this A&E two-night miniseries.
I'll start with the caveat that I am quite fond of both the book and the 1971 movie (one of the first movies I remember going to -- we were not a big movie-going family). I was looking forward to this miniseries to refresh and expand on Crichton's story, updating it for a new generation. Instead, the core novel has been turned into soap opera mush, and the added time available (180 minutes, minus commercials) is wasted on a parallel conspiracy theory story that not only adds nothing, but never really gets resolved.
This is a "hard" SF novel, focused on the science involved in diagnosing and dealing with Andromeda. Secondarily, it's about the pressure upon the four scientists (expanded to five in the miniseries, and all but the main one renamed), faced with multiple ticking clocks and a pathogenic horror that could, if unchecked, kill the world as efficiently as it's killed the town of Piedmont (Arizona in the book, New Mexico in the 1971 movie, Utah in 2008).
The miniseries turns the science into random and unfocused gobbledigook, including a talking computer that, evidently, does pretty much all the work for the research team. That leaves everyone time to chit-chat, mull over romances past and present, and hint at past events that are never explained (or that really aren't all that germane to the story). Meanwhile ...
The original novel and movie did include a bit of "conspiracy" about them. While Wildfire was originally set up by Congress at Dr Stone's recommendation, it was to decontaminate space probes and astronauts and deal with any infections they might bring back. The government looked upon it, and Project Scoop, as a way to gather and develop potential bioweapons; this comes out over the course of the original tale, but is really a sidelight to it, an addition to the caution that we Need To Be Careful Out There.
That's the part, though, that gets all the padding in the new miniseries. We get multiple government factions -- the DoD bioweapons head, his army gunsel, Homeland Security, a hapless president, a general whose motivations are mysterious -- and, of course, a doughty (and drug-addicted) journalist who's trying to track down this story and stay one step ahead of both the virus and the assassins sent to do him in.
It's layering cheap icing on the cake. It never really adds much -- except to distract from both the core story (which is bad) and the melodrama back at Wildfire (which, I guess, is good). You could excise the entire mess from the miniseries, and it wouldn't make a bit of difference to its resolution, but it would ratchet up the tension at Wildfire, rather than deflating it every time we cut to another scene.
There's so much more to criticize -- scientists too young (and pretty) for the long and distinguished careers they're supposed to have; the world's most incompetent governmental conspiracy; the laugh-out-loud climactic race against the Wildfire auto-destruct; the baby and old man who vanish after the first half; a telepathic, self-aware, highly-adaptive uber-virus that came from the future through a wormhole; egregious firing-squad breaches of security at a highly classified installation ... the list goes on.
When I saw ads in the movie theater for the miniseries, my thought was, "Wow, it looks like The Andromeda Strain, only with car crashes." I was at least partly correct: there were car crashes. But despite being able to be summed up with the same short paragraph in TV guide, I don't see much of the book, or original movie in here -- and that's a shame. In short, where this miniseries parallels the original, it does so in a muddled, mediocre fashion. Where it doesn't, it's even weaker. It adds nothing new to the original's vision, and the new stuff it does add feels more like it's one of those awful SciFi original movies than something from A&E.