Omi的变种BA.2开始接替原始Omi。号称隐形Omi，可以测出阳性，但是PCR分辨不出是Omi。症状mild但似乎会重复感染。

https://www.cityam.com/new-covid-variant-is-spreading-like-wildfire-in-scandinavia-ba-2-stealth-mutation-now-half-of-all-coronavirus-cases-in-denmark-and-rapidly-pushing-omicron-aside/

Anders Fomsgaard, who is chief physician and virus researcher at the Statens Serum Institut (SSI), told Danish media that a few cases have been seen in Norway where people who have been infected with Omikron have subsequently been infected with BA.2.

Statens Serum Institut (SSI) 的首席医师兼病毒研究员 Anders Fomsgaard 告诉丹麦媒体，在挪威发现了几例感染 Omikron 的人随后感染了 BA.2。

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Covid vaccines should still be effective, however, one of the reasons for BA.2’s rapid spread may be that it is more resistant to people’s immunity, “which allows the variant to infect better,” Fomsgaard reportedly said.

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据报道，新冠病毒疫苗应该仍然有效，然而，BA.2 迅速传播的原因之一可能是它对人们的免疫力具有更强的抵抗力，“这使得该变体能够更好地感染，”据报道，Fomsgaard 说。