For the tens of millions of Chinese people quarantined at home by the coronavirus epidemic, food deliveries and the people who prepare and deliver them are essential routes to the outside world.

But many shut-ins want to be sure that while their food is hot, the people providing it are not. In addition to the usual price and other information, many restaurants are also including a “reassurance guarantee” slip with the temperatures of the cooks, food packagers and courier for every order.

“These couriers have become the heroes of China along with the medical professionals,” said Shaun Rein, managing director of China Market Research Group. “The online food retailers have calmed the country down more than anyone, even the government, because they are showing people they can buy food at reasonable prices.”