Some 19,000 doctors across Nigeria are on strike for the fourth time since the start of the pandemic, with some of them complaining they haven't been paid in months.
The stoppage has left government-run hospitals and COVID-19 treatment centers short of staff.
The latest strike comes as Nigeria confronts an avalanche of new COVID-19 cases blamed on the delta variant.
Already Nigerian media outlets are reporting that patients - some with COVID-19 symptoms - are being turned away at short-staffed hospitals.
Other patients have been discharged into the streets or left to languish in hospital beds without being diagnosed or receiving treatment.
The strike is the fourth by resident doctors since the pandemic began. The longest lasted 10 days.
While the current stoppage does not affect specialist doctors or nurses, resident medical staff make up the bulk of health care workers at government hospitals throughout Nigeria, and they also staff most of the government-run treatment facilities for COVID-19.
The striking doctors worry about their patients but place the blame on the federal government, saying it failed to honor an earlier agreement reached after the last strike in April.
Nigeria's health minister Osagie Ehanire has said that he is "committed' to getting the resident doctors back to work, though he has said that most of their demands are issues to be solved by state governments, not his ministry.