“We’ll never fully solve this problem if we’re unwilling to look beyond our own borders and engage fully with the rest of the world,” Biden said. “We have to confront the coronavirus everywhere.”

Across the nearly 20-minute speech from Wilmington, Del., Biden emphasized the need for a coordinated national response and warned that fighting the outbreak will require dramatic changes to daily life. He encouraged Americans to heed the advice of public health officials and said his own campaign is taking precautions — including “reimagining” the format of events planned in Chicago and Miami.

But Biden, who has touted himself for months as the candidate who can beat Trump, also used the speech to challenge the president directly over his rhetoric and policies, and taking specific issue with Trump’s labeling of the coronavirus as a “foreign virus.”

“Downplaying it, being overly dismissive or spreading disinformation is only going to hurt us and further advantage the spread of the disease,” Biden said. “But neither should we panic or fall back on xenophobia.”

Trump’s vague description of his new European travel ban — which applies only to foreign nationals — sparked panic at airports, and White House officials spent the night and much of Thursday morning clarifying key elements of the administration’s response strategy.

Public health experts, meanwhile, panned the speech for falsely casting the outbreak as a “foreign virus” while the U.S. sits on the edge of a new, more urgent domestic emergency that’s forced a wave of school closures and event cancellations, and prompted fears that a crush of new cases could overwhelm hospitals. The U.S. has more than 1,000 confirmed cases, though a lag in the country’s testing capabilities has likely allowed the virus to spread undetected on a much broader scale.

Biden laid out a multipart plan for combating the disease that includes guaranteeing no-cost tests to anyone who needs it, and rushing resources to providers on the front lines of the response.

He slammed the Trump administration for its rocky rollout of testing kits and called for the creation of hundreds of mobile testing sites and wide-scale testing of people in nursing homes.