Coronavirus: Lifting restrictions in Wuhan will lead to second wave in August, says Lancet study

Researchers have suggested that lifting disease prevention measures in Wuhan this month could result in a second wave of coronavirus cases in late August.

In new modelling research published in The Lancet Public Health journal, the authors estimated that lifting control measures in April instead could delay a second peak until October, which would take pressure off health services in following months.

Mathematic modelling was used to simulate the effects of relaxing or pushing the current measures to a later date.

Schools and workplaces in Wuhan have been closed for months to contain the outbreak. But the research comes as Chinese authorities recently announced they would be easing the lockdown to allow people to travel again.

Lead researcher Dr Kiesha Prem, from the London School of Hygiene and Tropical Medicine (LSHTM), said: “The unprecedented measures the city of Wuhan has put in place to reduce social contacts in school and the workplace have helped to control the outbreak.

“However, the city now needs to be really careful to avoid prematurely lifting physical distancing measures, because that could lead to an earlier secondary peak in cases. But if they relax the restrictions gradually, this is likely to both delay and flatten the peak.”

A transmission model was developed using information about how people from different age groups and locations interact with one another to assess their effects on bringing the outbreak of coronavirus under control.

Researchers studied three potential scenarios: no interventions and no holidays, no social distancing but school winter break and lunar new year holidays to continue as normal, and intense infection control measures with schools closed and only essential workers allowed to work.

They also tested the model to see what the impact of lifting control measures would be in a staggered manner and at different stages of the outbreak.

The most effective scenario was the one in which physical distancing measures continued to be enforced, with staggered returns to work from the start of April.

Doing so could potentially reduce the median number of new infections by 24 per cent up until the end of 2020, delaying the second peak until October.

Co-author Dr Yang Liu, also from LSHTM, said results would differ from country to country, but one thing applied everywhere: “Physical distancing measures are very useful, and we need to carefully adjust their lifting to avoid subsequent waves of infections when workers and school children return to their normal routine.

“If those waves come too quickly, that could overwhelm health systems,” Dr Yang added.

The model does not take into account differences in susceptibility between children or that extreme distancing measures may have increased transmission of coronavirus within households in Wuhan.

It also did not assume differences in contact rates on an individual level.

But nevertheless, experts have called the study “crucial” for policy makers across the world who are trying to determine the effectiveness of physical distancing control measures.

Dr James Gill, honorary clinical lecturer at Warwick Medical School, said: “Even recognising that a series of assumptions within the study data have been made to account for unknowns … this model has produced some encouraging results.

“The proposals put forward here align with current practices and support the continuation of the quarantine efforts to reduce the case load burden on health infrastructures.

“Given the current levels of assumptions already in use for government public health assumptions already in use for government public health responses, it is gratifying to see a reasoned model which may be able to further guide policy makers,” he added.

“Hopefully this study will allow governments greater clarity in balancing population restrictions against their economic impact given the power demonstrated here.”