Global Covid-19 cases have surpassed 500 million, according to a Reuters tally, as the highly contagious BA.2 subvariant of Omicron surges in many countries in Europe and Asia.
The rise of BA.2 has been blamed for recent surges in China as well as record infections in Europe. It has been called the "stealth variant" because it is slightly harder to track than others.
South Korea leads the world in the daily average number of new cases, reporting more than 182,000 new infections a day and accounting for one in every four infections globally, according to a Reuters analysis.
