The current top-trending movie rentals and purchases were all released within the last few months with one notable exception: Contagion, the Gwyneth Paltrow-starring film from 2011 about a worldwide virus outbreak that starts in Hong Kong.

The thriller, in which — spoiler alert — Paltrow dies four days after contracting the virus but not before unleashing it around the world and causing millions of deaths, has been as high as No. 10 among films rented or bought on iTunes. Chatter on Twitter ("So many similarities between the movie plot and what's happening now," wrote one user) could be fueling the renewed interest. Google searches with the film's name have skyrocketed since early 2020, when news of the novel coronavirus broke.

The movie indeed has some similarities to the current coronavirus outbreak. Like the novel coronavirus, which causes the disease now called COVID-19, the movie virus jumped from animals to people. But there are also a lot of differences. The imaginary Contagion disease kills over 20% of those infected, a magnitude beyond the estimated 2% or so death rate in the current outbreak.

Scott Burns, the screenwriter ofContagion, wrote in an email to NPR that the filmmakers wanted to tell the story of a "plausible" outbreak — "not a Hollywood exaggeration."

"We were trying to tell a story that was credible within the boundaries of scientific understanding, but also illuminate how our world might respond — that is why the poster of the movie says 'nothing spreads like fear,' " he adds.

Even though the film is not a documentary, which the Centers for Disease Control and Prevention pointed out when the movie was released, it does have scientific content — sometimes accurate, sometimes not — about viral outbreaks. So we asked some specialists in global health and infectious diseases to fact-check the movie's science.

Birth of an outbreak

The movie saves the origin story of its virus for the last two minutes, when it shows a bulldozer razing trees where bats live to construct a pen for pigs. Once the pigs are in place, a bat flies over and drops a piece of banana that it's eating, which a pig then consumes. A virus carried by the bat mixes with a pig virus and mutates. A chef preps a presumably infected pig, puts his hand in its mouth and then without having washed up goes on to shake hands with Paltrow's character, transferring the virus to her.

Our experts think it's a realistic story — so realistic that Rebecca Katz, director of the Center for Global Health Science and Security at Georgetown University, says she often shows the film's ending to the students in her class on emerging infectious diseases.

"I show the last few minutes of Contagion to my class, to show the interconnectedness between animals, the environment and humans," Katz says.

"If you cut down trees, it changes the behavior of bats. The bats interact with swine, [which are] being raised for consumption, and humans then interact with infected swine as part of food preparations. This is just one example of how an emerging infectious disease can jump species into humans," she adds.

Glenn Wortmann, head of infectious diseases at MedStar Washington Hospital Center in Washington, D.C., agrees: "The film presents a plausible series of events" based on what we know about how viruses can possibly jump from animals to humans.

Finding infected people

When an outbreak is suspected in the movie, the CDC dispatches trained foot soldiers from the Epidemic Intelligence Service to outbreak areas to try to identify people with this new infectious disease, and it sets in motion disease control protocols to stem the outbreak. EIS is a real organization, and the movie's depiction of its staff earns praise for accuracy from the specialists we interviewed. The public health officials in the film identify potential cases and clusters of people with similar symptoms, track where those people had traveled, trace people in contact with those infected individuals and isolate the sick and exposed.

"This is very consistent with standard epidemiologic principles and practices," says Theresa Madaline, the health care epidemiologist at the Montefiore Health System in New York City, who notes that there is "always a sense of urgency" in identifying and properly responding to any emerging pathogen.

"What is accurate is the professionalism and devotion of staff in the EIS at CDC," says William Hanage, associate professor of epidemiology at the Harvard T.H. Chan School of Public Health. "These people are tireless, and I'm truly honored that several of my former students went on to serve in EIS. It's also not an especially glamorous job, for all its importance, and Kate Winslet's portrayal captures that." (Winslet's epidemiologist character, who works for EIS, becomes ill in the field early in the outbreak and is treated at a mass infirmary where the number of patients has overwhelmed resources.)

How does a new virus spread?

"Fomite" is not an often-heard vocabulary word, but it's spoken in the movie — and it's a critical term in the lingo of epidemiologists as they assess an outbreak's potential to spread.

The term refers to an object that, if touched by an infected person, can harbor the pathogens that the person is carrying and pass them on to a new individual. The movie does a good job explaining what a fomite is, says Wortmann.

"I think the movie highlighted various 'touch points' which can serve as fomites," he says — for example, a touch screen for orders in a restaurant, which was touched by Paltrow's server after handling Paltrow's credit card, and an elementary school door touched by Paltrow's son.

"All those surfaces harbored viruses, which can then be passed to whomever else touches that surface," says Wortmann, "which highlights the need to wash one's hands."

But the speed of transmission and some of the pathways shown were not fully accurate, notes epidemiologist Madaline. For example, the film hints that on the day Paltrow contracts the virus, she visits a casino, blows on dice and touches a bowl of nuts, which become "fomites" that spread the virus to others.

Our experts say Paltrow wouldn't necessarily be able to transmit the virus that quickly after becoming infected. "It would take some period of time — at least days — for her to shed the virus from her respiratory tract or saliva," says Madaline.

Before transmission can occur, says Amesh Adalja, senior scholar at the Johns Hopkins Center for Health Security and a volunteer spokesman for the Infectious Diseases Society of America, a virus that has entered cells in the body needs to make so many copies of itself that it reaches a threshold that activates the immune system to initiate coughing and sneezing.

For the novel coronavirus in China, he says, the period of time before transmission is possible is looking like five to six days.

Infection control for health workers

Taking precautions against contracting a virus is critical for health care providers and lab workers. Madaline notes that "in some scenes," the health care workers in the movie "wore personal protective equipment, which is what we normally do when caring for a patient who has a potentially transmissible disease."

But in other instances, that's not the case. A nun caring for patients at an airport infirmary wears only gloves and a mask as protective garb. That's also how Winslet's epidemiologist character protects herself early in the movie, when she rushes to find an infected person she has ordered to get off a bus.

Wortmann notes that "with a large outbreak, it would be difficult for all health care workers to [completely] maintain appropriate infection prevention measures, and I think the film recognizes those gaps."

Burial

The film shows some virus victims buried in mass graves. Madaline says such "graves could be used in outbreak settings when the ability to promptly bury the deceased exceeds morgue and funeral home capabilities or when burial itself is a high-risk activity for disease transmission." Indeed, during the 2014-2015 Ebola outbreak in West Africa and during the current outbreak in Congo, burial practices have changed because the body of someone who dies of Ebola is highly contagious.

Vaccine development

The way vaccine development was portrayed in the film was not terribly realistic, says Madaline. The scientist testing vaccine candidates in primates in the film inoculates herself to prove the vaccine works — and says that physician Barry Marshall inoculated himself with Helicobacter pylori to prove it was the cause of gastric ulcers and won a Nobel Prize for his work in 2005.

While this is true of Marshall, "the same action for vaccine development would not be effective or safe," says Madaline. "Efficacy and safety of vaccines must be established in multiple people, not just one person."

Infection rate

At a couple of points in Contagion, epidemiologists in the film discuss what the virus' "R₀" (pronounced R-naught), or reproductive rate, is. R₀ refers to the average number of people infected by one sick person, and the R₀ in Contagion climbs as the film progresses.

The very fact that the movie script mentions the R₀ factor is a plus, say the specialists. "The current outbreak has hopefully helped people understand the concept of R₀ a little better," says Hanage. "Folks should be able to understand that if people start trying to take precautions to avoid transmission," he says, "this number might decrease as it did for SARS, which is how it was defeated."

What worked? Hanage says hand hygiene, greater awareness of the risk of infection and making sure people took steps to avoid transmission to others if they did fall ill.

Fran Kritz is a health policy reporter based in Washington, D.C. Her work has appeared inThe Washington Postand Kaiser Health News. Find her on Twitter:@fkritz.

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