United States Surgeon General Dr. Vivek Murthy says that misinformation — much of it on tech platforms — is a public health threat that has cost people’s lives and prolonged the Covid pandemic.

As Murthy said in a Thursday press conference, health advisories are usually about things people physically consume: food, drinks, cigarettes. But the first advisory of his tenure in the Biden administration (he was also the surgeon general under President Obama) is about what we consume with our eyes and ears: misinformation.

The advisory comes with a set of guidelines on how to “build a healthy information environment,” with recommendations for everyone from social media users up to the platforms themselves (also: health workers, researchers, and the media). Murthy also went on some of those very platforms to spread the message, including Twitter and Facebook.

“Today, we live in a world where misinformation poses an imminent and insidious threat to our nation’s health,” Murthy said in a press conference, adding that “modern technology companies” have allowed misinformation and disinformation to spread across their platforms “with little accountability.”

The advisory isn’t a set of orders that must be followed by these companies, but the increased scrutiny and attention does put pressure on them to more aggressively combat the falsehoods spreading on their platforms.

This health advisory comes as Covid vaccination rates in the United States are dropping, while cases are picking back up, and the fast-spreading delta variant takes hold. The vast majority of Covid-related hospitalizations and deaths have been for people who aren’t vaccinated, despite the widespread availability of vaccines in the US. And with some people choosing not to get vaccinated because they believe misinformation about the vaccines, the Biden administration has reportedly decided it’s time to fight back.