31 January 2022. Since early 2020, Vietnam has witnessed four Covid-19 waves. The scale and spread of the ongoing fourth one has been far worse than the previous ones. As of January 24, Vietnam has discovered 163 cases infected with the Omicron variant.https://vietnamnet.vn/en/feature/four-covid-19-waves-in-vietnam-in-2021-2022-812175.html