Detained former Myanmar leader Aung San Suu Kyi has skipped three days of her trial in a junta court after Covid-19 was detected among her staff and she was placed in quarantine, a source with knowledge of the case said Monday.

The 76-year-old's civilian government was ousted in a coup last year that triggered mass protests, and she faces a raft of charges that could see her jailed for more than 150 years.

"Some people in her company have been infected by Covid-19... and so she's kept in quarantine, although she's not infected," the source said.

"We are worried because we haven't been able to see her." Former president Win Myint -- charged alongside Suu Kyi -- appeared at the court on Monday via video conferencing, the source added.

Suu Kyi and her personal staff have been fully vaccinated against Covid-19 since being taken into military custody, her lawyer told AFP last July.

She missed a hearing in September due to illness, and in October, her lawyer said her health had suffered from her frequent appearances before the junta-run court.

Journalists are barred from the proceedings in the military-built capital Naypyidaw, and her lawyers have been banned from speaking to the press.