Elon Musk says he has tested positive and negative for COVID-19 after taking four less-reliable tests.
Musk posted on Twitter saying there was something "extremely bogus" going on regarding his tests.
"Was tested for COVID four times today. Two tests came back negative, two came back positive. Same machine, same test, same nurse."
The high-profile tech executive said the tests were rapid antigen tests - a form of testing many experts have warned are not as effective as PCR testing which is widely seen as the gold standard.
One study suggested a rapid finger prick antigen test would return the wrong result for one person in every five.
In a reply to his tweet Musk hinted that perhaps false-positives were behind the massive rise in cases of the virus in the US.
"Could this be why we've been seeing such a major spike?" asked one person.
"If it's happening to me, it's happening to others," Musk replied.
"I'm getting PCR tests from separate labs. Results will take about 24 hours."
PCR stands for polymerase chain reaction. These tests detect the presence of the SARS-CoV-2 virus' genetic material, proving whether or not a patient is actively infected.
The rapid tests that Musk tweeted were inconclusive only look for antibodies, which suggest a patient is either infected or has been exposed to the virus. It can't tell if the patient is presently infected.
Musk has consistently downplayed the seriousness of the COVID-19 pandemic which has killed more than 243,000 people in the US alone.
In March, he made the now infamous, poorly-thought-out prediction that the US would see "probably close to zero" new cases of the virus by the end of April.
The US saw 163,000 new cases in the last 24 hours.
