Normal life a distant dream, whatever happens to lockdown

Two-thirds of the way through SA's three-week Covid-19 lockdown, sobering news has arrived in a new study from China, where the pandemic began.

As President Cyril Ramaphosa grapples with whether to end the lockdown at midnight next Thursday, researchers in Hong Kong said any country wanting to do so would have to closely monitor new infections and adjust its controls until a Covid-19 vaccine was available.

The scientists, co-led by Prof Joseph Wu from the University of Hong Kong, said China’s crackdown on movement had controlled the first wave of Covid-19 but there was a strong risk of a new outbreak.

“Without herd immunity against Covid-19, cases could easily resurge as businesses, factory operations and schools gradually resume and increase social mixing,” Wu's team said in The Lancet.

China has reduced Covid-19's average “reproductive number” — the people one person will infect — to below one, meaning infections are shrinking. But Wu said they would rise again if normal life resumed too quickly.

“Though control policies such as physical distancing and behavioural change are likely to be maintained for some time, proactively striking a balance between resuming economic activities and keeping the reproductive number below one is likely to be the best strategy until effective vaccines become widely available,” he said.

Balancing the resumption of economic activity with controls tight enough to prevent a resurgence “was likely to be the optimal strategy until effective vaccines become widely available, despite the fact that control policies — including social distancing, behavioural change and public awareness — will probably be maintained for some time”.

The analysis by Wu's team used data on confirmed Covid-19 cases between mid-January and February 29 in four cities and 10 provinces — all outside the pandemic epicentre of Hubei — with the highest numbers of cases.