. >> reporter: and above all, morishima has this message, don't relax preventive measures too soon oroo suddenly. nhk world, tokyo. >>> and the coronavirus continues to take a toll on numerous industries. crude oil futures briefly plummeted to an 18-year low in tokyo on wednesday. global oil prices are falling as the pandemic squeezes demand. on the tokyo commodity exchange crude futures for september delivery briefly dropped more than 30% to below 16,000 yen per kill le ki . may delivery on monday fell below zero for the first time ever. on tuesday, wgi futures contracts for june sank to $6 per barrel at one point. market watchers say futures prices for june could fall into negative territory due to over supply and a lack of storage capacity. >>> data compiled by a u.s. university show the number of confirmed coronavirus infections has topped 2.5 million worldwide. johns hopkins university says the death toll has surpassed 177,000. the united states has the most fatalities at over 45,000. the u.s. state of missouri is suing the chinese government over its handling of the coronavirus.