56 people got the coronavirus at a Starbucks in South Korea. The only people who didn’t were employees wearing masks.

• At least 56 cases of the novel coronavirus have been linked to a Starbucks in Paju, South Korea.
• Health officials attributed the outbreak to customers not wearing face masks, and a lack of proper ventilation inside the store, possibly related to the air conditioning.
• None of the employees at the cafe were infected. All of them had worn masks and gloves for the entirety of their shifts, according to local news.

At least 56 cases of the novel coronavirus in South Korea have been traced back to a Starbucks location in the city of Paju. Many customers were not wearing masks, and the poorly ventilated space likely contributed to the spread of the virus, according to local news.

But employees at the business were not infected, and experts believe it's because they were wearing masks.

Health officials said the outbreak originated from a single person infected with the virus who sat in the cafe next to the air conditioning system, which dispersed contagious aerosol particles throughout the space, according to Arirang News. The virus could also have spread as people touched contaminated surfaces such as tables and door handles, they said.

"Many of the visitors didn't wear masks, and there seems to be no proper air ventilation at the store even though air conditioners were in operation due to humid weather," Korea Centers for Disease Control and Prevention (KCDC) chief Jeong Eun-kyeong said of the outbreak, according to local media. "Even if infections did not occur via aerosol transmission, droplet transmission is also possible in a confined space, and the virus could have spread via hand contact."

The four employees working during the shift were not infected. Health officials said it's because staff consistently wore masks for the duration of their work hours.

South Korea, which had more success than many countries in containing the virus due to meticulous tracking and testing measures, saw a resurgence of the virus this summer.

The recent spike in cases has led health and government officials to mandate mask-wearing and consider more intensive social-distancing measures to control the outbreaks, Reuters reported.

Read more:

Wearing a mask doesn't reduce your oxygen levels, and 6 other mask myths you should stop believing now

Fauci calls photos of packed hallway in a Georgia high school 'disturbing'

Oleandrin, the coronavirus 'treatment' reportedly touted by Trump, comes from a plant so deadly it's been used to poison people