South Korea is now aiming to track down people infected with the coronavirus in less than an hour, using the latest technology.
The country has had one of the world’s most successful strategies for dealing with the virus, with fewer than 300 people recorded as having died from Covid-19.
Meanwhile Boris Johnson has hosted a global summit on vaccines, at at time when inoculation programmes around the world have been badly disrupted by the coronavirus pandemic.
Millions of babies in the developing world have not been given routine vaccines for diseases such as measles, cholera and yellow fever. It’s feared that large numbers of children will die or become seriously ill as a result.
Clive Myrie presents BBC News at Ten reports from Laura Bicker in South Korea and from Global Health Correspondent Tulip Mazumdar.