The crisis has spawned a new lexicon. Where once there were “blackout babies,” we can now expect a wave of “coronababies” and a new generation of “quaranteens” in 2033. Couples whose marriages are fraying under the pressures of self-isolation could be heading for a “covidivorce.”

A meme has been circulating on social media in recent days citing essential dating questions for 2020. “Can I see myself being quarantined with him? Does he come with toilet paper?”

On Valentine’s Day in Hong Kong, couples sent each other bouquets of masks and alcohol wipes, while flower sales in the city dropped 90 percent. In India, the news media have reported a surge in sales of condoms and other contraceptives.

In Wuhan, the original epicenter of the epidemic in China, Tian Fangfang, a young nurse, was photographed in her hazmat suit holding a handwritten request: “After the epidemic is over, I hope the government will assign me a boyfriend.” Later, in a video, she specified her preference that he be tall. CCTV, the national broadcaster, responded by circulating a compilation of eligible soldiers and police officers on its social media outlets.

Getting away with affairs has also become tougher. When a man from a small town in Santiago del Estero Province in Argentina bragged to friends that he had a tryst with a former lover returning from Spain, they reported him to the authorities. The entire town was put on lockdown on March 14. The man later became the first confirmed coronavirus case in the province.

The pandemic is altering notions of community and urban spaces, with people across the world gathering every day on balconies to applaud medical workers, perform music and even run marathons.

Sean Safford, a professor of sociology at Sciences Po in Paris, who is locked down in the city with his husband and their 7-year-old son, said the coronavirus had upended the human instinct to come together physically during a crisis by requiring that people do the opposite.