WARREN, Mich. (AP) — More than 130,000 autoworkers returned to factories across the U.S. for the first time in nearly two months Monday in one of the biggest steps yet to restart American industry, while an experimental vaccine against the coronavirus yielded encouraging results in a small and extremely early test.

At a Fiat Chrysler pickup truck assembly plant in Warren, outside Detroit, workers entered a giant white tent with a sign that read: “Let’s restart and keep each other safe.”

U.S. health authorities will be watching closely for a second wave of infections over the next few weeks and worry that Americans will disregard social distancing over the coming Memorial Day weekend, the unofficial start of summer.

Chinese President Xi Jinping defended China’s record, saying the country provided all relevant outbreak data to WHO and other countries, including the virus’s genetic sequence, “in a most timely fashion.”

But the Trump administration stepped up its attacks at the meeting, with U.S. Health and Human Services Secretary Alex Azar accusing WHO of failing to obtain the information the world needed as the outbreak emerged.