The Sweet Tooth Virus Explained

Contains spoilers for Netflix's "Sweet Tooth"

Since the moment the series debuted on Netflix, there's been something eerie about the way that the events of "Sweet Tooth" parallel the modern world. The story follows a young half-human, half-deer boy named Gus (Christian Convery), who loses his father (Will Forte) in the wake of a deadly pandemic. In addition to wiping out much of the world's population in "Sweet Tooth," the pandemic also leads to the creation of new hybrid species that many people consider a problem to be hunted down and killed. 

The virus, which is known in the show as H5G9 or "the Sick," has a history that stretches back to Jeff Lemire's limited comic book series, which Netflix's "Sweet Tooth" is based on. While the virus definitely plays a crucial role in the setup for the show, there are other details about it that "Sweet Tooth" also explores in its first season, including where the virus originated and what it does to the victims that it infects. H5G9 is definitely different than the real-life COVID-19 virus, but some fans are also wondering whether "the Sick" could eventually infest the real world.

"Sweet Tooth" definitely establishes H5G9 as a disease worth fearing, but that doesn't mean it's one that could ever actually exist. Many of the symptoms of H5G9 mirror actual diseases, and COVID-19 in particular. The main symptoms include having trouble breathing, coughing, and running a fever, but the overlap between H5G9 and COVID-19 stops there. The idea that a virus could create a world partially populated by hybrid humans is pure fiction, and it's a result of the specific circumstances that "Sweet Tooth" offers for how "the Sick" came to be. 

As the series explains, the H5G9 virus origin story starts in 1911, when a physician-in-training named James Thacker stumbles into a holy cave after befriending a local tribe. Thacker ultimately disturbs some holy remains, thereby unleashing the virus and the hybrid children simultaneously.

The native populations are wiped out almost immediately, but the events are eventually covered up and forgotten by history. More than 100 years later, a man named Fort Smith stumbles upon the same cave and disturbs the same remains, ultimately unleashing the virus on the modern world. 

In the comics that "Sweet Tooth" is based on, the virus is simply referred to as "the Sick." H5G9 is a creation of the Netflix show, and it's not exactly clear why the series' creators chose to add this more scientific name for the virus. It's possible that the decision was made in response to COVID-19, which made it clear that scientific names are very much a part of how diseases are described. It's also possible that the creators of "Sweet Tooth" simply decided that giving the virus another name made the world feel more fully fleshed out and grounded in a reality that viewers could understand and appreciate. 

Whatever the reasons may be, "the Sick" is clearly an intense disease, and utterly transforms the world of "Sweeth Tooth." Thankfully, people in the real world don't need to worry about catching H5G9, but that doesn't mean there aren't plenty of real diseases worth looking out for.