WASHINGTON, DC, United States (AP) — An election year already defined by a cascade of national crises descended further into chaos Friday with President Donald Trump declaring that he’s tested positive for the novel coronavirus after consistently playing down the threat.

Democratic challenger Joe Biden, who spent 90 minutes on stage with Trump in their Tuesday debate, tested negative and moved forward with plans to attend a campaign event in Michigan yesterday afternoon.

No one knows exactly what comes next.

At the least, the development focuses the campaign right where Biden has put his emphasis for months: on Trump’s response to a pandemic that has killed more than 200,000 people in the US. And for the short term, it’s grounded Trump in a quarantine, denying him the large public rallies that fuel his campaign.

The stunning development injected even deeper uncertainty into an election already plagued by the pandemic, deep economic anxiety and sweeping civil unrest. Just a month before election day, the country entered truly uncharted territory that has the potential to rattle global markets and political debates around the world.

“It’s a reminder that the American presidency is bigger than any one person, given the reach and depth this news has,” said Karen Finney, a Democratic consultant and top adviser to Hillary Clinton’s 2016 campaign.

She said the immediate focus should be on the Trumps’ health. But she added the development proves that not even Trump, no matter his talents for dictating headlines and framing events, can control a pandemic.

Trump tweeted yesterday that he’d begin quarantining and recovery. White House chief of staff Mark Meadows said that the president was resting, with mild symptoms.

The president has cancelled at least part of his weekend itinerary in Wisconsin, which is one of the three Great Lakes states Trump won by less than one percentage point in 2016 on his way to the presidency.

With election day just 32 days away, Americans have already begun voting in several states and tens of millions will receive absentee mail-in ballots or be eligible for in-person early voting in the coming weeks.

Strategists in both parties acknowledged the timing is bad for the Republican president.

“Trump’s main advantages, including incumbency, have been removed. Rallies, his main vehicle for mobilising his base, will no longer be possible. Fly-bys with Air Force One as a backdrop are gone,” said Republican strategist Rick Tyler, a frequent Trump critic.

He said that Trump’s infection also “fundamentally undercuts his entire campaign strategy, which was to ignore the pandemic and make unsubstantiated claims that we’ve turned the corner and are making an economic comeback.”

The news also raiseed questions about Biden’s schedule, although the Democrat planned to travel from Delaware to Michigan for a campaign event yesterday afternoon. Biden’s running mate, Kamala Harris, was slated for a trip to Las Vegas. The campaign said Harris tested negative for the virus as well.

The Democratic nominee has been much more cautious in his travel itinerary than Trump, with fewer public events and all of them following social distancing guidelines. Only Thursday did Biden’s campaign announce that it would resume door-to-door canvassing in addition to its phone and digital outreach to voters.

Biden’s primary care doctor, Kevin O’Connor, announced in a campaign statement that Biden and his wife, Jill, had tested negative.

“I’m happy to report that Jill and I have tested negative for COVID,” Biden tweeted. “Thank you to everyone for your messages of concern. I hope this serves as a reminder: wear a mask, keep social distance, and wash your hands.”