She hasn’t been tested, but Greta Thunberg is sure she has the coronavirus, though she says she’s now “basically recovered.” In an Instagram post, the teen climate activist says she went into self-isolation with her father two weeks ago after the pair returned home to Sweden from a trip around Central Europe, and both developed symptoms within days, per the Guardian. “I was feeling tired, had shivers, a sore throat and coughed,” the 17-year-old writes. But “my last cold was much worse than this” and “had it not been for someone else having the virus simultaneously, I might not even have suspected anything … and this it what makes it so much more dangerous.”

She explains her father “experienced the same symptoms, but much more intense and with a fever.” Neither were tested for COVID-19 in Sweden, where test kits are reserved for those requiring emergency medical treatment. “But it’s extremely likely that I’ve had it, given the combined symptoms and circumstances,” Thunberg writes. She hopes others can now learn from her presumptive case. Some people “might not notice any symptoms at all, or very mild symptoms … and can pass it on to people in risk groups.” In other words, “our actions can be the difference between life and death for many others,” she writes, urging others to stay at home.