Throughout the presidential campaign, the Democrats drew sharp contrasts with their Republican rivals over the matter of taking the virus seriously. President Biden’s staff members argued that by pursuing a lighter in-person campaign schedule, they were respecting scientific and medical recommendations and offering a glimpse of how Mr. Biden would lead the country through the pandemic — contrasting with President Donald J. Trump’s large in-person rallies.
None of the Democratic mayoral hopefuls are holding large rallies, though Eric Adams, the Brooklyn borough president, has faced criticism for fund-raising indoors. But they do face the challenge of breaking out of a crowded field while also signaling that they take seriously a pandemic that has devastated the city.
In an interview, Mr. Stringer wished Mr. Yang a quick recovery, but he also cast the development as a “wake-up call” to the mayoral field — a sign that some of the candidates are increasingly willing to draw mild contrasts with one another, and in particular with Mr. Yang.
“This is a dangerous business now, as long as this virus is raging, and we do have a special obligation to keep our people safe,” Mr. Stringer said.
“Nobody wants to see, you know, a colleague get sick,” he added. “But you don’t want to be the one to expose people. So, you know, whether it’s indoor fund-raising or up-close campaigning, we have to write new rules to keep people safe while we inoculate as many people as possible.”
A spokesman for Mr. Adams declined to comment on the reference to indoor fund-raising. In a statement, Mr. Yang’s co-campaign manager, Sasha Ahuja, said that the team’s strategy is informed by public health guidance.
“We hope every other campaign does the same and does as much or as little as they are comfortable with,” the statement said.
On Twitter, Mr. Yang used the moment to suggest a balm to speed his recovery.
“In all seriousness if you want me to feel better donate to my campaign!” he wrote. “Then I can relax.”