The movie Contagion opens with a montage that will provoke fear in anyone adhering to CDC social distancing guidelines: uncovered coughing, feverish-looking people crowded in subways and the sick sitting closely next to their loved ones.
The 2011 film — which dramatizes public health officials as they work to contain a highly lethal disease that ultimately consumes much of the world — has enjoyed a massive resurgence, with viewers drawn to a plot that has come to eerily resemble much of our daily lives.
Though some aspects of the movie are exaggerated or fictitious, according to Prof. Elizabeth Buckles, biomedical sciences, it has many lessons to offer when it comes to the importance of public health.
Like the zoonotic virus featured in Contagion, many pathogens most harmful to humans do not originate from them.
According to Buckles, although not all illnesses that infect animals can be transmitted to people, one of the factors that allows a virus to travel between species is the constant struggle between virus and host.
“The pathogen wants to be able to reproduce and the body that it’s infecting wants to be able to suppress it,” Buckles said. “The pathogen, even its host species, changes to try to get through our defense. Every once in a while, a virus or other pathogen changes enough so that it can infect another species.”
In one scene, as the government attempts to mount a response an agent asks Dr. Cheevers, the fictional head of the CDC, “Is there any way that someone could weaponize the bird flu?”. Dr. Cheevers responds, “Someone doesn’t have to weaponize the bird flu. The birds are already doing that.”
While Buckles agreed that pathogens can be weaponized, citing the mail-based anthrax attacks staged in the wake of 9/11, she took issue with the characterization that animals are “weaponizing” viruses against people.
“It’s not like birds are going out there saying, I am going to kill people with these weapons,” Buckles said.
While some parts of the movie Contagion are certainly dramatized, other parts are more accurate.
At one point in the movie, a doctor asks the husband of Beth Emhoff, who was one of the first to succumb to the disease, whether the main character’s work included contact with livestock, or if the couple kept any pets at home.
According to Buckles, these are reasonable questions to ask, in part because livestock and pets can infect one another.
“Whenever we are dealing with a disease outbreak on a farm, let’s say where multiple cows are dying, we always ask, what other animals are here?”
Detecting what animals carried a zoonotic illness can sometimes be detected at genomic level.
In Contagion, CDC scientists identify pig and bat DNA in the virus, hypothesizing that there may have been a “crossover” event.
A scientist says, “Somewhere in the world, the wrong pig met up with the wrong bat.”
This is a plausible scenario, Buckles explained.
“A bird, a pig, and a duck could all be living together. Their viruses could infect together and switch genomes, so you could have one gene sequence from the duck, one gene sequence from the pig, and one gene sequence from the chicken. Then, that could infect a human and make them very sick,” she said.
Though animals are often blamed for pandemics, the transfer of different species’ DNA into one virus can often be attributed to the effect that human disruption of natural environments has on animal disease dynamics.
“Bats always end up being the scapegoats for everything. Bats are very interesting because they can harbor a lot of viruses but are not symptomatic for them,” Buckles said. “How does the wrong bat end up near the wrong pig? That has to do with farming practices and wildlife destruction, because bats and pigs don’t usually hang out together.”
In the end sequence of Contagion, a bat infected a pig, which was then butchered by a chef who did not wash his hands afterward, transferring the infection to the human population.
Buckles considered this sequence plausible, emphasizing the importance of food safety even when there isn’t a zoonotic pandemic.
“Handwashing, proper cooking [are important]. Even if we are not talking about something as dramastic as an influenza or coronavirus, one of the main causes of human illness is foodborne illness,” Buckles explained. “Salmonella, E. coli, all of these things can usually be traced back to improper food handling.”
While not all scientific information in movies is appropriately contextualized, Buckles hopes that movies like Contagion help reinforce the human importance of public measures to lay viewers.
“Every dot on that [epidemiological modeling] curve is a human being, that was someone’s mother or father or favorite teacher,” Buckles said. “They had a story and voice that isn’t going to be there anymore. When we just focus on epidemiological models, we forget that. Art can bring back humanity.”