JOHANNESBURG (AP) — Africa’s confirmed coronavirus cases have surpassed 1 million, but global health experts tell The Associated Press the true toll is likely several times higher. That reflects the gaping lack of testing for the continent’s 1.3 billion people.

Large numbers of undetected cases are a danger for Africa with many of the world’s weakest health systems. Some countries have only a single testing machine. Some have conducted less than 500 tests per million people.

The virus has spread from cities into distant hinterlands, where few to no health resources exist. Experts predict a “slow burn” of the pandemic on the continent.