According to the latest epidemic prevention and control policy in Ningxia, starting from 0: 00 on March 17, Ningxia will give the health code "yellow code" to those who return to Ningxia three days after entering Ningxia. A nucleic acid test was conducted within 24 hours and 48 hours after entering Ning (the interval between them was more than 24 hours), and those with negative nucleic acid test turned into "green code" on the fourth day after entering Ning.
Such prevention and control measures are based on the recent national epidemic situation. At present, the global epidemic situation is still in an epidemic situation, and the domestic epidemic prevention and control situation is very complicated and severe. Ningxia, as one of the few provinces without epidemic situation in China, has epidemic situation in neighboring provinces, and the pressure on foreign defense investment is huge. Especially in this round of epidemic, there are many asymptomatic infected people. Many asymptomatic infected people can't know whether they are infected or not. If they are not found, they are a wandering source of infection.