Greta Thunberg believes she may have contracted coronavirus, though she was unable to be tested in her native Sweden because her symptoms were not severe.
The climate change activist, 17, wrote on Instagram Tuesday that she is “basically recovered” from her symptoms, but has spent the last two weeks isolating herself from her mother and sister following a trip to central Europe.
Thunberg said both she and her father Svante, 50, started feeling symptoms about 10 days ago upon returning from Brussels.
“I was feeling tired, had shivers, a sore throat and coughed,” she wrote. “My dad experienced the same symptoms, but much more intense and with a fever.”
Thunberg said that Swedes are unable to be tested for the virus unless they’re in need of emergency medical treatment, and because she wasn’t, she was simply told to stay at home and isolate herself.
“I have therefore not been tested for COVID-19, but it’s extremely likely that I’ve had it, given the combined symptoms and circumstances,” she wrote.
Thunberg went on to stress the fact that she “almost didn’t feel ill,” and she likely wouldn’t have suspected she had contracted the virus had it not been for “someone else having the virus simultaneously.”
“I would just have thought I was feeling unusually tired with a bit of a cough. And this i[s] what makes it so much more dangerous,” she wrote. “Many (especially young people) might not notice any symptoms at all, or very mild symptoms. Then they don’t know they have the virus and can pass it on to people in risk groups.”
RELATED VIDEO: Arizona Man Dies After Self-Treating Coronavirus with Chloroquine Phosphate, Says Hospital
Arizona Man Dies After Self-Treating Coronavirus with Chloroquine Phosphate, Says Hospital
The man consumed chloroquine phosphate, a drug used to treat malaria, lupus and rheumatoid arthritis, to treat COVID-19
She added that those not in an at-risk group have an “enormous responsibility” to stay at home to help slow the virus’ spread by flattening the curve.
“Our actions can be the difference between life and death in many others,” she wrote. “Please keep that in mind, follow the advice from experts and your local authorities and #StayAtHome to slow the spread of the virus. And remember to always take care of each other and help those in need.”
Europe, where Thunberg is based, has been hit particularly hard by the outbreak, with countries like Italy, Spain and Germany struggling in particular. Sweden, where Thunberg lives, has 2,059 confirmed cases of coronavirus and 33 deaths as of Tuesday afternoon, according to The New York Times.
As information about the coronavirus pandemic rapidly changes, PEOPLE is committed to providing the most recent data in our coverage. Some of the information in this story may have changed after publication. For the latest on COVID-19, readers are encouraged to use online resources from CDC, WHO, and local public health departments and visit our coronavirus hub.