There is a brand new harem scarem wipe-us-all-out pandemic movie out in theaters right now. No surprise, it is already number one at the box office. The movie is "Contagion" and it draws on the fear we all have of a return (or worse) of the 1918 Spanish Flu, which killed 50 million people around the world.

The virus that is the focus of "Contagion" is even worse. It's based on the real life NIPAH virus which originates in fruit bats and is highly deadly, killing almost 50 percent of victims (which are typically bats and pigs).

So, you're asking, could this happen to me? Is the movie realistic? The answer is, well, yes and no.

What Is Scientifically Realistic In "Contagion":

• The Nipah virus (called MEV1 in the movie) is accurately described. Discovered in 1998 in Malaysia, it has led to isolated outbreaks in humans though no sustained spread from human-to-human.

• It is a respiratory virus which causes brain infection (encephalitis), and many of the movie's symptoms are accurate (fever, headache, vomiting, muscle aches, trouble breathing, coma, and death).

• There is no vaccine and currently no effective treatment.

• There is always the risk of mutations rendering the virus more capable of transmitting human-to-human. This is in fact what occurred in 1918 with another novel virus (Spanish Flu) which originated in wild animals (probably birds).

• The response of the various agencies as they struggle to contain it (CDC, WHO, etc.), struggle to produce a vaccine in time (they ultimately make a live weakened virus vaccine which they grow in bat cells) is very plausible.

Also realistic is the breakdown of social structure, panic, looting, and the way that fear helps spread virus as people take fewer precautions and things spiral out of control. Hospitals struggle with limited surge capacity.

• The movie also has a pretty realistic view of attempts to contain the spread by isolating sick people and quarantining regions and roping of stadiums and filling them with sick people.

• The movie also describes how a respiratory virus can spread easily by coughing and even touching (fomites). We are reminded how often we touch our faces during the day and how much we touch each other.

What Doesn’t Work Scientifically In "Contagion":

• Though the Nipah virus is on the WHO’s potential pandemic list, the chances of it becoming easily transmissable while retaining its ability to kill easily (lethality) is very, very low. So the scenario in the movie is ultimately implausible.

• The incubation period (how long it will take to catch the NIPAH virus) is shortened by several days for dramatic effect.

• Though an increasing number of human contagions originate in wild animals, at the same time, the vast majority of these viruses never transmit easily among humans.

• Even though the scenario in the film supposedly takes place over 4 or 5 months, the fact that it is jammed into a two hour film makes it seem as if it is happening overnight.

Though the world is much more densely populated than it was in 1918, at the same time we have knowledge of viruses and how they spread and treatment for secondary infections and accompanying medical conditions that we didn't have back then. This knowledge and these treatments make the "Contagion" scenario even more unlikely.

One of the stated goals of the film is to make us more aware of potential contagions that can kill us. As I wrote in "False Alarm; the Truth About the Epidemic of Fear," these commercial attempts at “teaching” supposed public health can easily backfire, spreading fear and hype rather than facts and caution.

If we wash our hands more and get our yearly flu vaccine after seeing this film, so much the better, but if we wear a mask in public or hide in a bunker, so much the worse.

Marc Siegel, M.D. is a professor of medicine and medical director of Doctor Radio at NYU Langone Medical Center. He is a Fox News Medical contributor and author. His latest book is "The Inner Pulse: Unlocking the Secret Code of Sickness and Health."