he global death toll from Covid-19 passed 750,000 on Thursday, with some countries toughening controls as caseloads once again creep up.

The Latin America and the Caribbean region remained the global epicentre, accounting for almost one-third of all deaths and housing two of the worst-affected countries – Mexico and Brazil. Fear is growing in other regions, with countries including New Zealand and Italy tightening measures in a bid to secure hard-won gains in fighting the virus, which has now infected more than 20 million worldwide.

New Zealand, which earlier this week broke a streak of more than 100 days without a new infection, is scrambling to find the source of 17 new cases in its biggest city Auckland – which faces the prospect of a three-day lockdown being extended.

People living in London and those of Indian and Asian background are most likely to have been infected by the coronavirus, a key study by Imperial College London published on Thursday said, adding that 6% of England’s population has been infected so far. The 6% reflects about 3.4 million people. Over 100,000 volunteers took part in the study. Billed as the “world’s largest home antibody testing programme for coronavirus”, it tracked infections across England after the first peak.