South Korean health officials said it remains unclear what is behind the trend, with epidemiological investigations still under way.The prospect of people being re-infected with the virus is of international concern, as many countries are hoping that infected populations will develop sufficient immunity to prevent a resurgence of the pandemic.

The true number of lives lost is believed be much higher because of limited testing, cover-ups by some governments, and different counting practices. For example, in places like New York, Italy and Spain, many victims who died outside a hospital — say, in a home or a nursing home — have not been counted.

In an optimistic scenario, the WTO said global merchandise trade could fall 13% in 2020 and rebound 21% in 2021 — compared with a 0.1% contraction in 2019. In the optimistic scenario, gross domestic product could contract by 2.5% in 2020 and grow by 7.4% in 2021.

In a pessimistic case, the volume of global goods trade could drop by as much as 32% this year with the possibility of a 24% increase next year. In this situation, world GDP could shrink by as much as 8.8% in 2020 and expand by 5.9% in 2021.

Although the downturn is predicted to be short-lived, it’ll take time for economies to make up the lost ground. Even with unprecedented levels of monetary and fiscal stimulus, gross domestic product is unlikely to return to its pre-crisis trend until at least 2022.