SHANGHAI, Jan 14 (Reuters) - China’s blue-chip index slumped on Thursday, moving further away from a 13-year closing high earlier this week, as the country reported its biggest jump in COVID-19 cases in more than 10 months. ** At the close, the blue-chip CSI300 index was down 1.93%, its biggest daily fall since Sept. 9. The Shanghai Composite index fell 0.91%. ** COVID-19 infections in China’s northeastern Heilongjiang province nearly tripled, underscoring the growing threat ahead of a major national holiday when hundreds of millions of people usually travel. ** More than 28 million people are already under lockdown in Heilongjiang province and Hebei province, surrounding Beijing. ** Consumer firms led losses, with the consumer staples sector down 2.42%. Distiller Wuliangye Yibin Co Ltd tumbled 5.22% after touching a record high last week and surging more than 119% in 2020. ** The financial sector sub-index lost 1.17% and the healthcare sub-index slumped 1.8%. ** But stronger import growth figures for December underscored China’s robust domestic recovery, while exports grew more than expected as global coronavirus disruptions fuelled demand for Chinese goods. ** The smaller Shenzhen index ended down 1.42% and the start-up board ChiNext Composite index was weaker by 1.314%. ** Around the region, MSCI’s Asia ex-Japan stock index was firmer by 0.68%, while Japan’s Nikkei index closed up 0.85%. ** At 0703 GMT, the yuan was quoted at 6.4693 per U.S. dollar, 0.02% weaker than the previous close of 6.4681. ** Even after the drop on Thursday, the CSI300 is up 5% so far this year and the Shanghai stock index is up 2.7%. China’s H-share index listed in Hong Kong is up 5.2%. ** Shortly after the market close, China’s A-shares were trading at a premium of 37.03% over Hong Kong-listed H-shares. (Reporting by Andrew Galbraith; Editing by Ramakrishnan M.)