So now, some countries - wary of an influx of cases - are imposing Covid testing, and possible quarantine, on visitors from China.
The Covid wave hitting China is not due to some radical new variant, but Omicron in its different forms.
BF.7 and BQ.1 are both sub-lineages of BA.5, which itself is part of the Omicron "family" - more contagious, more infectious than any previous Covid strain.
