Elon Musk
Elon MuskReuters

Tesla CEO Elon Musk Thursday questioned the accuracy of COVID-19 tests after results he received showed he tested positive twice, and then negative twice, all on the same day.

"Something extremely bogus is going on. Was tested for covid four times today. Two tests came back negative, two came back positive. Same machine, same test, same nurse. Rapid antigen test from BD," Musk said in a tweet, possibly referring to Becton Dickinson's rapid antigen test.

Musk, who took rapid antigen tests on Thursday, said he was also awaiting results from polymerase chain reaction (PCR) tests from different labs, reported Reuters.

When asked by a Twitter user if he showed any symptoms, Musk said he had symptoms of a "typical cold".

"Nothing unusual so far," Musk added.

Becton Dickinson, which is one of the major suppliers of COVID-19 antigen tests, said in September it was investigating reports from U.S. nursing homes that its rapid coronavirus testing equipment was producing false-positive results.

Tanzania suspended the head of its national health laboratory in charge of COVID-19 testing and ordered an investigation, a day after President John Magufuli questioned the tests’ accuracy.

Magufuli said the test kits were faulty as they had returned positive results on a goat and a pawpaw fruit, among several non-human samples submitted for testing, with technicians left deliberately unaware of their origins.