Extending school and work closures at the coronavirus ' ground zero in China may delay a second wave of infections, researchers said on Thursday, urging the rest of the world to take note.With containment measures largely successful and the epidemic's epicentre now in Europe, China has loosened a two-month lockdown in the city of Wuhan where the new coronavirus is thought to have jumped from wildlife to people late last year. But a study in the Lancet Public Health journal suggested continuing Wuhan's shutdowns until April would push a potential second wave of Covid-19 until later in the year. That would give health services more time to recover and expand, potentially saving lives. "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," said Kiesha Prem, a specialist at the London School of Hygiene & Tropical Medicine (LSHTM), who co-led the research.The study used mathematical modelling to simulate either extending or relaxing school and workplace closures in Wuhan, a city of 11 million people. By lifting control measures now, a second rush of infections may occur in late August, the analysis suggested. But keeping lockdown measures until April would likely delay a second peak until October - giving healthcare workers a chance to regroup.